WO2014135921A1

WO2014135921A1 - Selection of radiomap data sets based on mobile terminal information

Info

Publication number: WO2014135921A1
Application number: PCT/IB2013/051775
Authority: WO
Inventors: Lauri Aarne Johannes Wirola; Tommi Antero Laine
Original assignee: Here Global B.V.
Priority date: 2013-03-06
Filing date: 2013-03-06
Publication date: 2014-09-12
Also published as: GB2511587B; GB2511587A; GB201314368D0; US20140256348A1; US9967853B2; EP2775744A1; EP2775744B1

Abstract

An apparatus that is one of a mobile terminal and a part thereof obtains a radiomap data set selected from a plurality of radiomap data sets. Each of the radiomap data sets at least partially pertains to the same geographical area. The radiomap data set is selected from the radiomap data sets at least based on mobile terminal information that is one of available at and provided by the mobile terminal. Also disclosed is an apparatus that stores the plurality of radiomap data sets and provides the selected radiomap data set to the mobile terminal.

Description

Selection of radiomap data sets based on mobile terminal information

FIELD OF THE DISCLOSURE

The invention relates to the field of radiomap-based positioning of mobile terminals, and more specifically to provision and selection of radiomap data sets to be used in such radiomap- based positioning.

BACKGROUND

Modern global cellular and non-cellular positioning technologies are based on generating large global databases containing information on cellular and non-cellular signals. The information may originate entirely or partially from users of these positioning technologies acting as data collectors.

The data provided by these data collectors is typically in the form of "fingerprints", which contain a location that is estimated based on, e.g., received satellite signals of a global navigation satellite system (GNSS) and measurements taken from one or more radio interfaces for signals of a cellular and/or non-cellular radio network. In the case of measurements on cellular signals, the results of the measurements may contain a global and/or local identification of the cellular network cells observed, their signal strengths and/or pathlosses and/or timing measurements like timing advance (TA) or round-trip time (RTT). For measurements on wireless local area network (WLAN) signals, as an example of signals of a non-cellular network, the results of the measurements may contain a basic service set identification (BSSID), like the medium access control (MAC) address of observed access points, and/or the service set identifier (SSID) of the access points, and/or the signal strength of received signals (received signal strength indication RSSI or physical Rx level in dBm with a reference value of 1 mW, etc.), and/or pathloss estimates and/or timing measurements (like e.g. RTT).

This data may then be transferred to a server or cloud, where the data (usually of a multitude of users) may be collected and where a radiomap for positioning purposes may be generated (or updated) based on the data. Such a radiomap can for instance comprise estimates for respective coverage areas of base stations (coverage area estimates) and/or radio channel models, wherein a base station serves as an example for a node of a communication network. In the end, this radiomap may be used for estimating the position of mobile terminals. This may function in two modes. The first mode is the terminal-assisted mode, in which the mobile terminal performs the measurements of the cellular and/or non-cellular air interface, provides the measurements to the remote server, which in turn, based on the radiomap, determines and provides the position estimate back to the mobile terminal. The second mode is the terminal- based mode, in which the mobile terminal has a local copy of the radiomap (or only a subset of the global radiomap). This subset copy is downloaded by the mobile terminal from a remote server for the area of interest (e.g. a small area around the current location, for a whole country, or so). This subset copy can of course be pre-installed to the mobile terminal in the factory, but even in that case the data needs to be refreshed at some point.

SUMMARY OF SOME EXAMPLE EMBODIMENTS OF THE INVENTION

The radiomap data files can be very large in size. To exemplify, in Paris urban/suburban area covering roughly 10 x 10 km there are more than 10 million WLAN access points (APs). Transferring the radiomap information for each of those APs to the mobile terminal is very burdensome and consumes a lot of server resources, network bandwidth and data over air, in turn resulting in high costs for the user of the mobile terminal. For instance, in the above example, just transferring the BSSIDs for the 10 million APs as radiomap data consumes 10.000.000 · 8 bytes = 80 Mbytes of radiomap data. Similarly, also, in the cellular radiomap case, the number of neighbor cells can grow so high that the radiomap files consume a lot of transmission bandwidth and mobile terminal storage. It is readily seen that transferring such large amounts of data over e.g. a cellular communication network is not feasible especially under roaming conditions, since data transmission costs may be significantly higher in a foreign (roaming) network as compared to data transmission costs in a home network.

As an example embodiment of the present invention, a first method is described, which is performed by an apparatus that is one of a mobile terminal and a part thereof. The first method comprises obtaining a radiomap data set selected from a plurality of radiomap data sets. Each of the radiomap data sets at least partially pertains to the same geographical area. The radio- map data set is selected from the radiomap data sets at least based on mobile terminal information available at and/or provided by the mobile terminal. The first method may for instance further comprise determining a position estimate for the mobile terminal at least based on the radiomap data set. It may additionally or alternatively comprise requesting a radiomap data set (e.g. in a request), for instance for the geographical area. The mobile terminal information (and optionally further information pertaining to the requested radiomap data set) may for instance be provided together with the request or separate therefrom.

As a further example embodiment of the present invention, a second method is described, which is performed by an apparatus. The method comprises storing a plurality of radiomap data sets. Each of the radiomap data sets at least partially pertains to the same geographical area. The method further comprises providing, to a mobile terminal, a radiomap data set selected from the plurality of radiomap data sets. The radiomap data set is selected from the radiomap data sets at least based on mobile terminal information available at and/or provided by the mobile terminal.

As further example embodiments of the present invention, moreover, a first apparatus is described, which is configured to realize or comprises respective means for realizing the actions of the first method (and any of its embodiments described herein), and a second apparatus is described, which is configured to realize or comprises respective means for realizing the actions of the second method (and any of its embodiments described herein). The means of these apparatuses can be implemented in hardware and/or software. They may comprise for instance a processor, e.g. for executing computer program code for realizing the required functions, a memory storing the program code, or both. Alternatively, they could comprise for instance circuitry that is designed to realize the required functions, for instance implemented in a chipset or a chip, like an integrated circuit.

As further example embodiments of the present invention, moreover a third apparatus is described, which comprises at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause an apparatus at least to perform the actions of the first method (and any of its embodiments described herein), and a fourth apparatus is described, which comprises at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause an apparatus at least to perform the actions of the second method (and any of its embodiments described herein).

Any of the described apparatuses may comprise only the indicated components or one or more additional components. Any of the described apparatuses may be a module or a component for a device, for example a chip. Alternatively, any of the described apparatuses may be a device, for instance a server or a mobile terminal. Any of the described apparatuses may for instance at least comprise a user interface, a communication interface and/or an antenna.

As further example embodiments of the present invention, moreover a first non-transitory (e.g. tangible) computer readable storage medium is described, in which computer program code is stored, which causes an apparatus to realize the actions of the first method (and any of its embodiments described herein) when executed by a processor, and a second non-transitory computer readable storage medium is described, in which computer program code is stored, which causes an apparatus to realize the actions of the second method (and any of its embodiments described herein) when executed by a processor. The computer readable storage medium could be for example a disk or a memory or the like. The computer program code could be stored in the computer readable storage medium in the form of instructions encoding the computer-readable storage medium. The computer readable storage medium may be intended for taking part in the operation of a device, like an internal or external hard disk of a computer, or be intended for distribution of the program code, like an optical disc.

It is to be understood that also the computer program code by itself has to be considered an embodiment of the invention.

In certain embodiments of the described methods, the radiomap data set is selected by the first apparatus (or the third apparatus), or by another apparatus that is either the second apparatus (or the fourth apparatus) or an apparatus that is associated with the second apparatus (or the fourth apparatus).

In certain embodiments of the described methods, a position estimate for the mobile terminal is determinable at least based on the (obtained) radiomap data set.

In certain embodiments of the described methods, the mobile terminal information comprises information pertaining to a technical capability of the mobile terminal, and at least one of the radiomap data sets has radiomap information contributing to a quality of a position estimate for the mobile terminal only if the mobile terminal has the technical capability indicated in the mobile terminal information. The technical capability may for instance be a capability of the mobile terminal to identify, in addition to a serving node of a cellular communication network, also at least respective resources of one or more neighboring nodes that are of the same or one or more other cellular communication networks and to exploit information associated with the identified resources for determining a position estimate for the mobile terminal, a capability of the mobile terminal to measure a received signal strength and/or to estimate a path loss, and/or a capability of the mobile terminal to receive and process signals on frequency channels of at least one frequency band of at least two frequency bands of one or more (e.g. non-cellular) communication networks, wherein the at least one frequency band of the at least two frequency bands on the channels of which the mobile terminal is able to receive and process signals is identified in the mobile terminal information.

In certain embodiments of the described methods, the mobile terminal information comprises at least one of an indication of a type and/or a transfer rate of a radio connection of the mobile terminal, via which the radiomap data set is to be obtained, an indication of a maximum file size of the radiomap data set that is to be obtained, and an indication of a quality for a position estimate for the mobile terminal that is considered to be satisfactory at the mobile terminal.

It is to be understood that the presentation of embodiments of the invention in this section is merely exemplary and non-limiting.

Other features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not drawn to scale and that they are merely intended to conceptually illustrate the structures and procedures described herein.

BRIEF DESCRIPTION OF THE FIGURES

Fig. 1 is a schematic illustration of a positioning system in which example embodiments of apparatuses according to the present invention are deployed;

Fig. 2 is a block diagram of one of the apparatuses of Fig. 1 according to an exemplary embodiment of the invention;

Fig. 3 is a flow chart illustrating a method according to an exemplary embodiment of the invention for instance performed by the apparatus of Fig. 2;

Fig. 4 is a block diagram of the other apparatus of Fig. 1 according to a further exemplary embodiment of the invention; Fig. 5 is a flow chart illustrating a method according to a further exemplary embodiment of the invention for instance performed by the apparatus of Fig. 4;

Fig. 6 is a flow chart illustrating a method according to a further exemplary embodiment of the invention for instance performed by the apparatuses of Fig. 2 and 4;

Fig. 7 is a flow chart illustrating a method for selecting a radiomap data set according to a further exemplary embodiment of the invention; and

Fig. 8 a schematic illustration of examples of tangible storage media according to the present invention.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS OF THE INVENTION

Fig. 1 shows a positioning system 1 , in which example embodiments of apparatuses according to the present invention can be deployed. In Fig. 1 , mobile terminal 2 is capable of identifying nodes 3-1, 3-2 and 3-3 of one or more communication networks. Each of nodes 3-1, 3-2 and 3-3 provides radio coverage in a respective coverage area 6-1, 6-2 and 6-3. Based on models of the coverage areas and/or radio channel models of the identified nodes 3-1, 3-2 and 3-3, mobile terminal 2 is capable of determining its position, for instance as an intersection of coverage areas 6-1, 6-2 and 6-3, or by triangulation, to name but a few non- limiting examples. Non-limiting examples of nodes of communication networks (also denoted as communication network nodes herein) are base stations (or sectors thereof) of a cellular communication network, such as for instance a second generation (2G, for instance the Global System for Mobile Communication (GSM), the General Packet Radio System (GPRS), the Enhanced Data Rates for GSM Evolution (EDGE) or the High Speed Circuit- Switched Data (HSCSD)), third generation (3G, for instance the Universal Mobile Telecommunication System, UMTS, or CDMA-2000) or fourth generation (4G, for instance the Long Term Evolution, LTE, system, the LTE Advanced (LTE-A) system or the IEEE 802.16m WiMAX system) communication network, or an AP or beacon of a non-cellular radio communication network, such as for instance a WLAN network, a Bluetooth system, a radio-frequency identification (RFID) system a broadcasting system such as for instance Digital Video Broadcasting (DVB), Digital Audio Broadcasting (DAB) or Frequency-Modulated (FM) / Amplitude-Modulated (AM) radio, a Near Field Communication (NFC) system, etc.). A cellular communication network may for instance be characterized by a basically seamless pavement of a geographical area (usually in the order of at least hundreds or thousands of square kilometers) with cells in which coverage is provided by respective communication network nodes that are operated by the same operator, which network may for instance support communication handover between cells. Conse- quently, a non-cellular communication network may be characterized as a communication network that does not have all of these properties.

A coverage area generally depends on a plurality of parameters of both the communication network node that provides the coverage area (inter alia antenna beamwidth and positioning, transmission power) and the propagation environment (inter alia pathloss and shadowing caused by obstructing elements). A model of a coverage area (also denoted as coverage area model in the following) may for instance be or at least be desired to be representative of a coverage area. However, at least temporary deviations may occur between the model and the actual coverage area, for instance in case of changes or movement of the coverage area. A model for a coverage area may for instance be a model representing hard boundaries of a coverage area, or a model that represents a coverage area in a statistical sense, for instance by means of a probability (density) function. An example of such a statistical representation of a coverage model is a multi-normal distribution. A coverage area model may only be a coarse model of a coverage area, e.g. an elliptical or polygonal model. The coverage area model may equally well be constituted by a set of grids of a grid of regions, e.g. a rectangular grid of regions. In a simple exemplary case, a coverage area model may be represented by a position of the coverage providing node and information on the reach of this coverage providing node.

Identifying a node of a communication network by a mobile terminal may for instance require that the mobile terminal is able to receive one or more signals (e.g. a broadcast channel), which are sent by the node with a pre-defined minimum quality (for instance defined in terms of a signal-to-noise ratio or a signal-to-noise and interference ratio), and/or is able to at least partially receive and correctly decode one or more signals sent by the node, and/or is able to receive and correctly decode an identifier of the communication network node that provides the coverage area (for instance a Medium Access Control (MAC) address or another identifier). Some or all of these conditions for identifying a communication network node may for instance be met when the mobile terminal is within the coverage area of the communication network node. Therein, a node of a communication network may for instance have an identifier that is unique (e.g. globally unique) at least in the communication network (and for instance also in all other communication networks). Equally well, a node of a communication network may for instance have an identifier that is not unique (e.g. only locally unique) in the communication network, but that is at least unique in a subregion of the region covered by the communication network. Receiving signals or information from the node may for instance require that the mobile terminal is technically capable to receive such signals or information. Thus a mobile terminal may have to support the transmission technology (e.g. the communication standard) used by the node. Receiving signals or information from the node may also require that the mobile terminal is entitled to communicate with or at least receive signals or information from the node.

As an alternative or addition to coverage area models, also radio channel models (aka radio propagation models) for communication network nodes may serve as a basis for determining a position of a mobile terminal, if a mobile terminal is able to measure a received signal strength and/or a path loss. A radio channel model may for instance describe how the power of a signal emitted by a communication network node decays with increasing distance from the communication network, for instance under consideration of further parameters as for instance the radio transmission frequency. To this end, the radio channel model may for instance take into account effects of free space propagation, slow fading and fast fading, to name but a few examples. The radio channel model may for instance be parameterized by and/or characterized by one or more parameters, such as for instance a path loss exponent, as it is known to a person skilled in the art. A non-limiting example for a radio channel model is the Okumura/Hata model, which predicts the path loss L_P in dB as follows:

wherein / denotes the radio transmission frequency, z_r is the transmit antenna height, h_R is the receive antenna height, a(h ) is a correction factor for the height of the receiving antenna (which is for instance approximately zero for h_R = 1.5 m) and d is the distance between transmit and receive antenna.

Now, if radio channel model information (for instance comprising an identifier of the radio channel model to be used, for instance in case that more than one radio channel model is in use, and/or one or more of the parameters characterizing the radio channel model, so that the radio channel model for instance indicates the pathloss as a function of the distance between the transmitting node and the mobile terminal) is available for an identified communication network node, and if a strength of a signal from this communication network node as received at the mobile terminal (or the path loss experienced by this signal) has been measured at the mobile terminal, an estimate of the distance towards the communication network node can be determined and exploited (e.g. among further information) to determine a position estimate for the mobile terminal. This may additionally require knowledge of the transmission power level of the signal as used by the communication network node, which may for instance be predefined, included into the radio channel model or signaled to the mobile terminal, to name but a few examples. For instance, consider the exemplary case where the mobile terminal identifies three communication network nodes with associated coverage area models and radio channel models. Based on the coverage area models only, which are exemplarily considered to be elliptical, the position estimate for the mobile terminal would be obtained as the intersection of three ellipses (as schematically shown in Fig. 1). By further considering the radio channel models associated with the identified communication network nodes and measured received signal strengths at the mobile terminal with respect to each of these communication network nodes, the position estimate for the mobile terminal can be further narrowed down by considering the distances from the mobile terminal to the three communication network nodes, ideally yielding an intersection of three arcs (the radius of each given by the respective distance from the mobile terminal to the respective communication network node, the position of which is for instance contained in the elliptical coverage area models) somewhere within the intersection of the three ellipses.

The communication network nodes may for instance be identified based on identifiers. Non- limiting examples of such identifiers are cellular cell identifiers (e.g. a Mobile Country Code (MCC), a Mobile Network Code (MNC), a Local Area Code (LAC) and/or a Cell Identity (CID) in case of coverage areas of a 2G mobile communications system, a UTRAN Cell ID (UC-ID) in case of a 3G mobile communications system, or an LTE Cell Identity in case of a 4G communications system), and identifiers of WLAN access points (e,g. a Medium Access Control (MAC) identifier of a WLAN access point).

Returning to Fig. 1, information on the coverage areas 6-1, 6-2 and 6-3 of the respective communication network nodes 3- 1, 3-2 and 3-3 is contained in radiomap data sets (RMDSs) that mobile terminal 2 requests from RMDS server 4. RMDS server 4 stores a plurality of RMDSs, which are for instance generated by RMDS generation/updating unit 5, which may either be the same unit as RMDS server 4, or may be separate (and even remote) therefrom. The RMDSs, in particular the coverage area model information and/or the radio channel model information contained therein, may for instance be generated/updated based on so-called "fingerprints" (measurements comprising a position of a mobile terminal and a list of one or more nodes of one or more communication networks that the mobile terminal was able to identify at that current position, optionally also with an indication of the received signal strength and/or of the estimated path loss, for instance to allow derivation of radio channel model information) provided by mobile terminals acting as data collectors.

According to embodiments of the present invention, the plurality of RMDSs stored at RMDS server 4 for instance at least partially pertain to the same geographical region, but have different sizes and thus for instance allow for different qualities (e.g. in terms of accuracy and/or availability) of position estimates determined based on these different RMDSs, respectively. That the RMDSs at least partially pertain to the same geographical region may for instance be understood in a way that at least a respective part of the information comprised in a respective RMDS pertains to this same geographical region. For instance, the respective coverage areas on which the RMDSs contain information may at least partially overlap (for instance in this same geographical region). It may for instance be the case that the RMDSs entirely pertain to the same geographical region. Equally well, one RMDS of the plurality of RMDSs may pertain to a first region, and another RMDS of the plurality of RMDSs may pertain to a second region that comprises the first region but also one or more further regions. The "same geographical region" may for instance be a region in which the mobile terminal to be positioned is located. The "same geographical region" may for instance be the region for which the RMDS selected from the plurality of RMDSs is requested by the mobile terminal.

This inter alia allows reducing server resources, transmission bandwidth (transmission costs), transmission duration and/or mobile terminal storage space by only providing the mobile terminal with those RMDS information it can actually technically exploit (as will be further explained below), and/or to trade off position estimate quality against transmission bandwidth (transmission costs) and/or transmission duration.

As illustrated in Fig. 1, mobile terminal 2 requests an RMDS from RMDS server 4, and obtains, in response to the request, an RMDS from RMDS server 4. Based on this obtained RMDS, and on information on the nodes 3-1, 3-2 and 3-3 that mobile terminal 2 is currently able to identify, mobile terminal 2 is then capable of determining an estimate of its position. The RMDS may for instance be requested by mobile terminal 2 each time when mobile terminal 2 enters into or is activated in a geographical area, for which no RMDS is yet available at mobile terminal 2. The request for the RMDS may comprise an identification of an RMDS that has been selected at the mobile terminal based on mobile terminal information (e.g tech- nical capabilities of the mobile terminal, as will be further discussed below), or may comprise mobile terminal information based on which an RMDS is selected at RMDS server 4.

Fig. 2 is a schematic block diagram of an example embodiment of an apparatus 2 according to the invention, e.g. of the first or third apparatus according to the invention. Apparatus 2 for instance is or forms a part (e.g. as a module) of a mobile terminal, e.g. mobile terminal 2 of Fig. 1. Non- limiting examples of a mobile terminal are a cellular phone, a personal digital assistant, a laptop computer, a tablet computer or a multimedia player.

Apparatus 2 comprises a processor 20. Processor 20 may represent a single processor or two or more processors, which are for instance at least partially coupled, for instance via a bus. Processor 20 executes a program code stored in program memory 21 (for instance program code causing apparatus 2 to perform one or more of the embodiments of a method according to the invention (as for instance further described below with reference to Figs. 3, 6 and 7), when executed on processor 20), and interfaces with a main memory 22. Some or all of memories 21 and 22 may also be included into processor 20. One of or both of memories 21 and 22 may be fixedly connected to processor 20 or at least partially removable from processor 20, for instance in the form of a memory card or stick. Program memory 21 may for instance be a non-volatile memory. It may for instance be a FLASH memory (or a part thereof), any of a ROM, PROM, EPROM and EEPROM memory (or a part thereof) or a hard disc (or a part thereof), to name but a few examples. Program memory 21 may also comprise an operating system for processor 20. Program memory 20 may for instance comprise a first memory portion that is fixedly installed in apparatus 2, and a second memory portion that is removable from apparatus 2, for instance in the form of a removable SD memory card. One or more RMDSs that are useable by apparatus 2 to determine positions may for instance be stored in program memory 21. Main memory 22 may for instance be a volatile memory. It may for instance be a RAM or DRAM memory, to give but a few non-limiting examples. It may for instance be used as a working memory for processor 20 when executing an operating system and/or programs.

Processor 20 further controls a communication interface 23 configured to receive and/or output information. For instance, communication interface 23 may be configured to exchange information with and/or to identify nodes 6- 1, 6-2 and 6-3 of system 1 of Fig. 1, and/or to exchange information with RMDS server 4 of system 1 (see Fig. 1). This may for instance comprise sending requests for an RMDS and/or mobile terminal information to RMDS server 4 and/or receiving one or more RMDSs from RMDS server 4. This communication may for instance be based on a wireless connection. Communication interface 23 may thus for instance comprise circuitry such as modulators, filters, mixers, switches and/or one or more antennas to allow transmission and/or reception of signals. In embodiments of the invention, communication interface 23 is configured to allow communication according to a 2G/3G/4G cellular communication network and/or a non-cellular communication network, such as for instance a WLAN network. Nevertheless, the communication route between mobile terminal 2 and RMDS server 4 may equally well at least partially comprise wire-bound portions. For instance, RMDS server 4 may be connected to a back-bone of a wireless communication network (associated with mobile terminal 2) via a wire -bound network such as for instance the internet.

Processor 20 further controls a user interface 24 configured to present information to a user of apparatus 20 and/or to receive information from such a user. Such information may for instance comprise information on a position estimate determined by positioning based on an RMDS, and/or information pertaining to a selection of an RMDS from a plurality of RMDSs. User interface 24 may for instance be the standard user interface via which a user of apparatus 2 with apparatus 2 to control other functionality thereof, such as making phone calls, browsing the Internet, etc.

Processor 20 may further control an optional GNSS interface 25 configured to receive positioning information of an GNSS such as Global Positioning System (GPS), Galileo, Global Navigation Satellite System (i.e. "Globalnaja Nawigazionnaja Sputnikowaja Sistema", GLONASS) and Quasi-Zenith Satellite System (QZSS). It should be noted that, even in case apparatus 2 has a GNSS interface 25, the user of apparatus 2 or for instance the mobile terminal comprising apparatus 2 can still benefit from using RMDS-based positioning technologies, since these technologies may allow for significantly reduced time-to-first- fix and/or lower power consumption as compared to GNSS-based positioning. Also, not all applications on a mobile terminal may require highly accurate GNSS-based position estimates. For instance, for a local weather application, it may be sufficient to use RMDS-based position estimates. Also, and perhaps even more important, RMDS-based positioning technologies work indoors, which is generally a challenging environment for GNSS-based technologies.

The components 21 -25 of apparatus 2 may for instance be connected with processor 20 by means of one or more serial and/or parallel busses. Fig. 3 is a flowchart 300 of an exemplary embodiment of a method according to the invention, e.g. of the first method according to the invention, in particular if step 302 is considered to be optional. Therefore, step 302 is given in dashed lines in Fig. 1. The steps of flowchart 300 can for instance be performed by apparatus 2 of Fig. 2, for instance when apparatus 2 is deployed as mobile terminal 2 or as a part thereof in the system 1 of Fig. 1. A step performed by apparatus 2 may preferably be understood such that corresponding program code is stored in memory 21 and that the program code and the memory are configured to, with processor 20, cause apparatus 2 to perform the step. Equally well, a step performed by apparatus 2 may preferably be understood such that apparatus 2 comprises according means for performing this step. For instance, communication interface 23 and/or processor 20 may be considered as means for obtaining the selected RMDS. Processor 20 may also be considered as means for determining a position estimate for the mobile terminal based on the obtained RMDS.

In a first step 301, an RMDS is obtained, which has been selected from a plurality of RMDSs based on mobile terminal information. More details on this mobile terminal information will be provided below. The RMDS obtained in step 301 may be obtained in response to a request for an RMDS launched by mobile terminal beforehand (as shown in Fig. 6). Launching this request may also form part of flowchart 300. Furthermore, selecting the RMDS that is obtained in step 301 may also form a step of flowchart 300 (prior to step 301), if the selecting is performed by apparatus 2. Otherwise, the selecting may be performed by another entity. Then, for instance also the provision of the mobile terminal information on which the selection is based to the entity that performs the selection may form part of flowchart 300.

In (optional) step 302, then a position estimate for a mobile terminal that is or contains apparatus 2 is determined based on the RMDS obtained in step 302 (and for instance based on further information, namely a list of one or more identified nodes of communication networks for which coverage areas and/or radio channel models are contained in the RMDS). It should be noted that step 302 may be performed several times based on the same RMDS. For instance, the RMDS obtained in step 301 may be used for determining position estimates as long as the mobile terminal comprising apparatus 2 only moves within an area that is covered by the coverage area model information and/or radio channel model information comprised in the RMDS obtained in step 301. Fig. 4 is a schematic block diagram of an example embodiment of an apparatus 4 according to the invention, e.g. of the second or fourth apparatus according to the invention. Apparatus 4 for instance is or forms a part (e.g. as a module) of a server, e.g. RMDS server 4 of Fig. 1.

Apparatus 4 comprises a processor 40. Processor 40 may represent a single processor or two or more processors, which are for instance at least partially coupled, for instance via a bus. Processor 40 executes a program code stored in program memory 41 (for instance program code causing apparatus 4 to perform one or more of the example embodiments of a method according to the invention (as for instance described below with reference to Figs. 5, 6 and 7), when executed on processor 40). Processor 40 further interfaces with a main memory 42 (for instance acting as a working memory) and a mass storage 44, which may for instance store a plurality of different RMDSs as already described above. An example of different RMDSs will be described below with respect to Table 1.

Memories 41 and/or 42 may also be included into processor 40. Memories 41 and/or 42 may be fixedly connected to processor 40 or may at least partially be removable from processor 40, for instance in the form of a memory card or stick. Program memory 41 may for instance be a non-volatile memory. It may for instance be a FLASH memory (or a part thereof), any of a ROM, PROM, EPROM and EEPROM memory (or a part thereof) or a hard disc (or a part thereof), to name but a few examples. Program memory 41 may also comprise an operating system for processor 40. Program memory 40 may for instance be implemented as a hard disk. Main memory 42 may for instance be a volatile memory. It may for instance be a RAM or DRAM memory, to give but a few non-limiting examples. It may for instance be used as a working memory for processor 40 when executing an operating system and/or programs. Mass storage 44 may for instance be embodied as mass storage device, for instance with capacities of several Gigabytes or several Terabytes. It may either be fixedly connected to processor 40, or may be releasably connectable thereto. Non-limiting examples of mass storage 44 are a direct-attached storage (DAS), a storage area network (SAN) or a Network-attached storage (NAS).

Processor 40 further controls a communication interface 43 configured to receive and/or output information. For instance, communication interface 43 may be configured to exchange information with mobile terminal 2 of system 1 (see Fig. 1). This may for instance comprise receiving requests from mobile terminal 2 and providing one or more RMDSs to mobile terminal 2. This communication may for instance be based on a wireless connection. Communi- cation interface 43 may thus for instance comprise circuitry such as modulators, filters, mixers, switches and/or one or more antennas to allow transmission and/or reception of signals. In embodiments of the invention, communication interface 43 is configured to allow communication according to a 2G/3G/4G cellular communication network and/or non-cellular communication network. Equally well, communication interface 43 may be a wire -bound network interface. It may for instance allow apparatus 2 to communicate with a network such as the internet. The communication route from the RMDS server 4 to mobile terminal may then for instance comprise both wire-bound and wireless portions. The wire-bound portion may for instance connect communication interface 43 with a backbone of a wireless communication network, and the wireless portion may connect the wireless communication network with mobile terminal 2.

The components 41 -44 of apparatus 4 may for instance be connected with processor 40 by means of one or more serial and/or parallel busses.

It is to be noted that the circuitry formed by the components of apparatuses 2 and 4 may be implemented in hardware alone, partially in hardware and in software, or in software only, as further described at the end of this specification.

Program memories 21 of Fig. 2 and 41 of Fig. 4 may be considered as tangible storage media, which may in particular be non-transitory storage media. They may comprise respective programs, which in turn comprise respective program code (for instance a set of instructions). Examples of such tangible storage media will be presented with respect to Fig. 8 below.

Fig. 5 is a flowchart 500 of an exemplary embodiment of a method according to the invention, e.g. of the second method according to the invention. The steps of flowchart 500 can for instance be performed by apparatus 4 of Fig. 4, for instance when apparatus 4 is deployed as RMDS server 4 or as a part thereof in the system 1 of Fig. 1. A step performed by apparatus 4 may preferably be understood such that corresponding program code is stored in memory 41 and that the program code and the memory are configured to, with processor 40, cause apparatus 4 to perform the step. Equally well, a step performed by apparatus 4 may preferably be understood such that apparatus 4 comprises according means for performing this step. For instance, mass storage 44 may be considered as means for storing a plurality of RMDSs, and communication interface 43 and/or processor 40 may be considered as means for providing the selected RMDS to the mobile terminal. In a first step 501, a plurality of RMDSs is stored. In a second step 502, an RMDS selected from the plurality of stored RMDSs is provided, for instance to mobile terminal 2 of the system 1 of Fig. 1. The RMDS is selected based on mobile terminal information. This selecting may for instance be performed at apparatus 4, for instance based on mobile terminal information provided to apparatus 4. This selecting may then for instance form a step of flowchart 500 (prior to step 502). Alternatively, the selection may be performed by another entity, e.g. by mobile terminal 2 of the system 1 of Fig. 1, and information on this selection may then for instance be provided to apparatus 4 to enable apparatus 4 to provide the selected RMDS.

Fig. 6 is a flowchart 600 of an exemplary interaction of mobile terminal 2 and RMDS server 4 of the system of Fig. 1. Therein, the actions taken by mobile terminal 2 are presented on the left side of Fig. 6, whereas the actions taken by RMDS server 4 are presented on the right side of Fig. 6. The actions taken by mobile terminal 2 can of course be performed by apparatus 2 of Fig. 2, and the actions taken by RMDS server 4 can of course be taken by apparatus 4 of Fig. 4.

In a first step 601, the mobile terminal 2 checks whether a new RMDS is required. This may for instance be the case if no RMDS is available at mobile terminal 2 for the region in which mobile terminal 2 is currently located, for instance because mobile terminal 2 is activated for the first time in this region or because mobile terminal has just been moved into this region, to give but a few examples. Another scenario in which a need for a new RMDS may arise is a scenario where an RMDS for the current geographical area is already present, but where a position estimate quality associated with the present RMDS is no longer considered sufficient at mobile terminal 2, for instance because an application has been started on mobile terminal 2 that has higher position estimate quality requirements than one or more other applications that were active when the present RMDS was requested. The more severe position estimate quality requirements may then for instance be signaled to the RMDS server in a request for an RMDS (see step 602 described below), so that is can be considered in the selection of a suited RMDS from the plurality of RMDSs. A further scenario where a need for a new RMDS may arise is a situation where an RMDS available at the mobile terminal for the desired geographical region is considered to be too old, for instance older than two months. The age of a RMDS may for instance be determined based on the time when the RMDS was obtained at the mobile terminal, or by a time when the RMDS was originally generated, which time may for instance be included in the RMDS. If the finding in step 601 is true, a request for an RMDS is launched by mobile terminal 2 to RMDS server 4 in step 602. This request may for instance comprise information identifying or allowing identifying a geographical region for which a RMDS is desired or required by the mobile terminal 2. This information may for instance comprise a cell ID identifying a current cell (and thus the associated (serving) node) of a cellular communication network. This cell ID may for instance be part of a hierarchy of area identifiers used in the cellular communication network, for instance as follows for 2G/3G/4G cellular communication networks, respectively:

2G Cell Info: Mobile Country code (MCC) - Mobile Network Code (MNC) - Local Area Code (LAC) - Cell Identity (CID)

3G Cell Info: Mobile Country code (MCC) - Mobile Network Code (MNC) - UTRAN Cell ID (UC-ID); (Note: The UC-ID may in some implementations have a fine structure with RNC-ID (Radio Network Controller) and Cell ID within the UC-ID.)

4G Cell Info: Mobile Country code (MCC) - Mobile Network Code (MNC) - LTE Cell Identity

Based on the cell ID, then a geographical region for which the RMDS is desired or required by the mobile terminal may be determined as the region (cell) identified by the cell ID itself, or as the region (plurality of cells) identified by a superordinated identifier, such as for instance the region identified by the LAC in a 2G cellular communication network. As an example, in a 2G cellular communication network, a cell ID may be of the form (1,2,3,4), the corresponding LAC may then be obtained as (1,2,3), the MNC may be obtained as (1,2), and the MCC may be obtained as (1).

For instance, the extent of the geographical region for which an RMDS is provided may be pre-defined in a way that the RMDS shall always comprise all cells having the same specific superordinated identifier (e.g. the same LAC, MNC or MCC in case of a 2G cellular communication system) as the cell with the cell ID provided in the request. The RMDS may then for instance comprise coverage area models and/or radio channel models for all theses cells (respectively associated with nodes) of the cellular communication network. It may then also be advantageous to have, in the RMDS, also the coverage area models and/or radio channel mod- els of cells of other cellular networks of the same operator, for instance of those cells thereof that cover a similar geographical region. Thus for instance, not only coverage area models and/or radio channel models of 2G cells, but also of 3G and/or 4G cells would be comprised in the RMDS. This advantageously takes into account that mobile terminals nowadays can quickly change between these different cellular communication networks of the same operator.

Additionally or alternatively, the cell ID provided by mobile terminal 2 in a request for an RMDS may for instance be used to identify an RMDS having coverage area models and/or radio channel models of APs (nodes) of a non-cellular communication network (e.g. a WLAN) for a desired/required region. This may for instance be performed by identifying an RMDS having coverage area models and/or radio channel models for those non-cellular APs (e.g. WLAN APs) with coverage areas substantially (e.g. by at least 50, 70 or 90 percent) covering the same region as the region covered by the plurality of cells of a cellular communication network that are identified based on the cell ID (or its superordinated parts) as described above.

Additionally or alternatively, if an RMDS pertaining to nodes of a non-cellular communication network is desired, an already available position estimate may be included into the request for the RMDS, and the region for which the RMDS is required/desired may then be identified based on this position information. For instance, RMDSs may pertain to one or more grid elements of a grid of regions (e.g. a grid with rectangular regions covering the Earth surface). Based on the position estimate, then for instance a grid element comprising the position estimate may be identified, and this grid element (or this grid element and one or more neighboring grid elements for instance chosen to arrive at a pre-defined size of a region, e.g. 2x2, 4x4 or 6x6 km, to name but a few examples) may be considered as the region for which the RMDS is required/desired. The RMDS may then for instance comprise the coverage area models and/or the radio channel models for those APs that have coverage areas at least partially overlapping this region.

As described above, the request launched by mobile terminal 2 in step 601 may contain information identifying or allowing identifying a geographical region for which an RMDS is desired or required. Alternatively, no such information may be provided, and then the request for an RMDS is for instance considered to relate to a predefined region, e.g. to all regions for which information is available. According to the embodiments of the present invention, an RMDS (e.g. the requested RMDS of the flowchart of Fig. 6) is selectable from a plurality of RMDSs that at least partially pertain to the same geographical area. Thus there exist several RMDSs that at least partially (or for instance even completely) pertain to the same region for which an RMDS is required/desired by the mobile terminal.

In embodiments of the present invention, these RMDSs have different contents, for instance taking into account different technical capabilities of the mobile terminal (for instance if the mobile terminal is capable of receiving and processing a signal on a first, a second or both frequency bands of two frequency bands of a WLAN communication network and thus to exploit respective radiomap information for these one or more frequency bands).

In embodiments of the present invention, the RMDSs for instance have different respective sizes and thus allow for a different respective quality of a respective position estimate for a mobile terminal if determined at least based on the respective RMDS. The size may for instance denote the size of a file that stores the RMDS, and may for instance be measured in Bytes. The quality of a position estimate may for instance pertain to an accuracy of the position estimate, and/or an availability of the position estimate. A position estimate may for instance be considered accurate if it is close to an actual position of the terminal, and may be considered inaccurate if it is far apart from the actual position of the terminal. The availability of the position estimate may for instance relate to a probability that a position estimate can be determined at all, because a coverage area mode and/or radio channel model for at least one node of a communication network identifiable by the mobile terminal (i.e. at least one node close to the mobile terminal) is contained in the RMDS. For instance, if an RMDS only contains coverage area models and/or radio channel models for communication network nodes with a low spatial density, the availability of the position estimate may be significantly lower as compared to an RMDS containing coverage area models and/or radio channel models for communication network nodes with a high spatial density. The different sizes of the RMDSs may for instance be caused by the fact that the RMDSs contain different amounts of information for the same number of communication network nodes, or contain information for different numbers of communication network nodes (for instance since a spatial density of these communication network nodes is different and/or because the RMDSs pertain to geographical regions of different size). Having a plurality of RMDSs with respective different sizes and different associated position estimate qualities may for instance allow trading transmission durations/costs for the transmission of the RMDS to the mobile terminal and/or mobile terminal storage space against a quality of the position estimate.

In the exemplary embodiment of Fig. 6, the selection of the RMDS from the plurality of RMDSs is performed by the RMDS server 4, based on mobile terminal information provided to the RMDS server 4, for instance together with the request in step 601, but equally well in a separate communication (for instance as a response to an according inquiry from RMDS server 4). This mobile terminal information may for instance pertain to technical capabilities of the mobile terminal indicative of whether the mobile terminal is actually capable of exploiting specific radiomap information contained in some of the RMDSs or not. Additionally or alternatively, the mobile terminal information may for instance be indicative of download and/or storage capabilities of the mobile terminal, which may be used to decide if certain RMDSs of large size cannot be downloaded to the mobile terminal within an acceptable time and/or cannot be stored on the mobile terminal. Additionally or alternatively, the mobile terminal information may for instance indicate that a certain quality of the position estimate is considered at the mobile terminal, so that it would not make sense to provide the mobile terminal with an RMDS leading to a higher quality.

In step 603, the request and the mobile terminal information is received at RMDS server 4. The RMDS server 4 may then for instance use information on the geographical region for which an RMDS is required/desired by the mobile terminal to identify a plurality of RMDSs that at least partially pertain to this geographical region. Based on the mobile terminal information, then an RMDS is selected by RMDS server 4 from this plurality of RMDSs in step 604.

In step 605, the selected RMDS is then provided from RMDS server 4 to mobile terminal 2. The flow of actions of RMDS server 4 then jumps back to step 603, i.e. RMDS server 4 await further requests for an RMDS from mobile terminal 2 (or from other mobile terminals).

At mobile terminal 2, the RMDS selected in step 605 is received in step 606.

In step 607, which is also entered if the finding in step 601 above is false, it is checked if a new position estimate is required at the mobile terminal. This may for instance be the case if an application of the mobile terminal requires a position estimate. Equally well, a position estimate could be required at the mobile terminal in regular time intervals. If step 607 is true, mobile terminal 2 then determines a position estimate for itself in step 608 based on the RMDS obtained in step 606, for instance by identifying one or more nodes of one or more communication networks that are currently in the proximity of the mobile terminal (and thus identifiable by the mobile terminal) and processing respective coverage area models and/or radio channel models for these identified nodes comprised in the obtained RMDS as already described above.

If step 607 is false, the flow of actions at mobile terminal 2 then jumps back to step 601.

In the following, further features and example embodiments of the invention will be described, that equally pertain to the first method, first and third apparatus and first non- transitory computer readable storage medium according to the present invention (as exempla- rily embodied in Fig. 1 (mobile terminal 2), 2, 3 and 6, and also to the second method, second and fourth apparatus and second non-transitory computer readable storage medium according to the present invention (as exemplarily embodied in Fig. 1 (RMDS server 4), 4, 5 and 6). Unless not technically contradictory, all of these embodiments shall be considered to be disclosed in any possible combinations with each other. Furthermore, none of the features of these embodiments, unless stated otherwise, shall be considered essential or inevitable for the present invention.

In some example embodiments of the present invention, the RMDS is selected by an apparatus that obtains the RMDS (e.g. mobile terminal 2 or a part thereof) or by another apparatus that is either an apparatus that provides the RMDS (e.g. RMDS server 4) or an apparatus that is associated with the apparatus that provides the RMDS.

In some example embodiments of the present invention, a position estimate for the mobile terminal is determinable at least based on the (obtained) RMDS. This may for instance be performed at the mobile terminal, for instance by the apparatus that obtained the RMDS.

In some example embodiments of the present invention, the RMDS comprises at least one of respective coverage area model information (e.g. information representative or characteristic of a coverage area model (and thus also of the coverage area) for a communication network node) and radio channel model information (e.g. information representative or characteristic of a radio channel model for a communication network node, for instance describing the path- loss or attenuation of a signal emitted by the communication network node at least as a function of the distance towards the communication network node) of one or more nodes of one or more communication networks. A position estimate for the mobile terminal may then for instance be determined at least based on respective coverage area model information and/or radio channel model information of one or more identified nodes of the one or more communication networks in a proximity of the mobile terminal (e.g. those nodes that can be observed or identified by the mobile terminal, as discussed with respect to Fig. 1 above).

In some example embodiments of the present invention the obtaining or the providing of the RMDS is triggered by one of an entry of the mobile terminal into or an activation of the mobile terminal in a geographical area for which no RMDS is available at the mobile terminal, a change of at least a part of the mobile terminal information (as for instance discussed with respect to step 601 of Fig. 6 above), and a decision that an available radiomap is outdated. To this end, the mobile terminal may for instance have a pre-defined maximum age threshold for RMDSs. For instance, as soon as an RMDS available at the RMDS is determined to have exceeded this maximum age threshold, the obtaining or the providing of the RMDS may be triggered. The age information may for instance be included in or associated with the available RMDS. The available RMDS may for instance have been obtained before or may be pre- installed (e.g. during provisioning of the mobile terminal, before the mobile terminal is sold to a customer) in the mobile terminal.

In some example embodiments of the present invention, the mobile terminal information comprises at least one of:

an indication of a type and/or a transfer rate of a radio connection of the mobile terminal, via which the RMDS is to be obtained,

an indication of a maximum file size of the RMDS that is to be obtained,

an indication of a quality for a position estimate for the mobile terminal that is considered to be satisfactory at the mobile terminal, wherein a position estimate for the mobile terminal is determinable at least based on the radiomap data set, and

an indication of at least one technical capability of the mobile terminal comprising at least one of

- a capability of the mobile terminal to identify, in addition to a serving node of a cellular communication network, also at least respective resources of one or more neighboring nodes that are of the same or one or more other cellular communication networks and to exploit information associated with the identified resources for determining a position estimate for the mobile terminal,

- a capability of the mobile terminal to measure a received signal strength and/or to estimate a path loss, and

- a capability of the mobile terminal to receive and process signals on frequency channels of at least one frequency band of at least two frequency bands of one or more communication networks, wherein the at least one frequency band of the at least two frequency bands on the channels of which the mobile terminal is able to receive and process signals is identified in the mobile terminal information.

The indication of a type (e.g. a non-cellular type or a cellular type, wherein in the latter case, a further differentiation may be made whether the mobile terminal is currently roaming or not) and/or a transfer rate (e.g. in bit/s) of a radio connection of the mobile terminal, via which the RMDS is to be obtained, may for instance be exploited in the selection of the RMDS to decide if an RMDS would take too long to transfer to the mobile terminal and/or would be too costly (for instance in case of a cellular connection). The indicated type of the connection may for instance not be the same as a type of the nodes to which the RMDS that is requested and/or selected pertains. For instance, although a non-cellular-based connection is indicated to be used for obtaining the (selected) RMDS, the RMDS may pertain to nodes of a cellular communication network, since an also available RMDS pertaining to nodes of a non-cellular communication network may for instance be too large for download or storage on the mobile terminal, or because the RMDS pertaining to nodes of the cellular communication network is too large to be downloaded via a cellular-based connection.

The indication of the maximum file size of the RMDS that is to be obtained may for instance be derived from a remaining storage space left on the mobile terminal. Considering this maximum file size in the selection of the RMDS is advantageous since it can then be avoided that an RMDS is selected that cannot be stored on the mobile terminal anyway.

The indication of a quality for the position estimate for the mobile terminal that is considered to be satisfactory at the mobile terminal may for instance depend on the quality requirements of one or more applications that are installed on the mobile terminal. These applications may have different requirements with respect to the quality (in terms of accuracy and/or availability) of a position estimate. For instance, an application for presenting current or predicted weather information to the user of the mobile terminal may generally only require a position estimate with a coarse accuracy, e.g. several hundred meters or even kilometers, whereas an application for navigating a user within a town or building has much more advanced accuracy requirements, e.g. in the range of one or more meters only. At the mobile terminal, thus for instance the maximum quality requirements among all applications installed on the mobile terminal, or among all currently active applications of the mobile terminal, may be determined as the quality for the position estimate for the mobile terminal that is considered to be satisfactory at the mobile terminal. When selecting the RMDS, it may then not be required to select an RMDS leading to a quality that is above the indicated (satisfactory) quality.

An example of a plurality of RMDSs substantially pertaining to the same geographical region is given with respect to Table 1 given below.

Table 1 contains a header row denoting the meaning of the columns of the table as well as ten actual rows of table content, each of which representing an RMDS (here exemplarily in the form of a file) that may for instance be provided by a server (like for instance RMDS server 4 of Fig. 1) to a mobile terminal (such as for instance mobile terminal 2 of Fig. 1). The first four RMDSs are of cellular type, as indicated by the first column of Table 1, and will be referred to as "cellular RMDSs" in the following. They pertain to cellular communication network nodes only. The last six RMDSs are of WLAN type (as an example for a non-cellular type), and will be referred to as "WLAN RMDSs" in the following. They pertain to WLAN APs only. The information comprised in an RMDS is specified in the second column of Table 1, either coverage area models (abbreviated as "CAMs") and/or radio channel models (abbreviated as "RCMs") can be present here, in case of cellular RMDSs for serving nodes and/or neighboring nodes, in case of WLAN RMDSs for APs. In case of WLAN RMDSs, there may either be a CAM for a single frequency band (2.4 GHz or 5.0 GHz, representing the two frequency bands 2.4-2.4835 GHz, and 5.15-5.725 GHz, respectively), or two respective CAMs for two frequencies bands (2.4 GHz and 5.0 GHz, again representing the two frequency bands 2.4- 2.4835 GHz, and 5.15-5.725 GHz, respectively).

The third column of Table 1 ("Connectivity type") contains exemplary mobile terminal information, namely the connectivity type, i.e. an indication on the type of connection via which the RMDS is to be provided from the RMDS server to the mobile terminal (wherein the bandwidth of the cellular connectivity type is here exemplarily assumed to be smaller than the bandwidth of the WLAN connectivity type). Therein, a connectivity type of "cellular (local)" denotes a connectivity type where the mobile terminal is not roaming (roaming is assumed to significantly increase the costs for data transmission in the cellular connectivity type).

Table 1 : Examples of RMDSs

The fourth column of Table 1 ("Required measurement support") also contains information related to mobile terminal information, namely information on a technical capability that a mobile terminal must have to fully exploit the information contained in the respective RMDS.

Therein, "Cell ID of serving nodes" denotes the capability of a mobile terminal to identify the Cell ID of the node with which it is currently associated when communicating in a cellular communication network, and/or with which it would be associated when starting to communicate in the cellular network. The serving node may for instance be the node (e.g. of one or more cellular communication networks in which the mobile terminal is capable and/or entitled to communicate) from which the mobile terminal receives signals with the highest signal strength as compared to the signals received from other nodes of the one or more cellular communication networks.

A more advanced mobile terminal can also be capable of identifying, in addition to the Cell ID of the serving node, at least respective resources, of one or more neighboring nodes, i.e. nodes of cells that are in the neighborhood of the serving cell (the cell in which coverage is provided by the serving node). Accordingly, in the third cellular RMDS in Table 1, the RMDS contains coverage area models for both the serving node and the neighboring node(s). Examples of respective resources of one or more neighboring nodes (and thus of their respectively associated cells) are pilot signals, frequency channels, timeslots, spreading codes, scrambling codes, spatial channels (e.g. antenna beams or spatial eigenmodes) etc.. Such resources may for instance allow at least locally identifying the one or more neighboring nodes and thus using radiomap information (e.g. coverage area model information and/or radio channel model information) for the one or more neighboring nodes comprised in the RMDS. This radiomap information for the one or more neighboring nodes may for instance be comprised in the RMDS respectively subordinated (e.g. as "child" data sets) to the serving nodes (e.g. to the "parent" data sets). Thus when a mobile terminal has (globally) identified the serving node, it can access the RMDS and also retrieve the radiomap information of the (locally identified) neighboring nodes.

For instance, in case of a 3G system, the Cell ID of the serving nodes may comprise the Mobile Country code (MCC), the Mobile Network Code (MNC) and the UTRAN Cell ID (UC- ID) and may thus serve as a globally unique identifier of a node (and its associated cell). An example of resources of neighboring nodes/cells useable to at least locally identify these neighboring nodes/cells are the PCPICH (Primary Common Pilot Channel) and/or the UTRA Absolute Radio Frequency Channel Number for the Downlink (UARFCN-DL), which may for instance at least be partially reused across the communication network and may only serve as a locally unique identification of neighboring nodes.

The resources (e.g. PCPICH/UARFCN) of the neighboring nodes/cells may for instance be identified by the mobile terminal to be able to perform a handover to another node/cell (these resource may of course be identified by the mobile terminal for the serving cell as well, e.g. in addition to the Cell ID of the serving cell). It may thus be particularly advantageous to exploit this information, which has to be produced by a mobile terminal anyway, also for positioning purposes. However, this may require making this information available from a unit of the mobile terminal that produces this information (e.g. a modem) to a unit (e.g. apparatus 2 of Fig. 2) of the mobile terminal that can exploit this information for positioning.

Equally well, an even more advanced mobile terminal may for instance be capable of identifying, in addition to the Cell ID of the serving node, also the Cell ID (e.g. the MCC, MNC and UC-ID in case of a 3G communication network) of one or more neighboring nodes, e.g. each in a globally unique sense. In that case, it may not be necessary to provide the radiomap information for the neighboring nodes as "child" data sets of the "parent" data sets of serving nodes in the RMDSs, because these Cell IDs are globally unique. Nevertheless, identifying the Cell IDs of neighboring nodes may require receiving System Information Blocks also from the neighbor nodes in addition to the serving nodes, which may be quite costly in terms of implementation, processing power and/or energy (e.g. high battery consumption). Since the Cell IDs of the neighboring nodes are basically useless for the normal operation of the mobile terminal, the majority of the modems used in mobile terminals do not report the Cell IDs of neighboring nodes. Consequently, exploiting the globally unique identification of both serving nodes and neighboring nodes may require substantially changing the functionality of these modems, as compared to the above-described case where only locally unique identification of neighboring nodes is required.

A further technical capability of the mobile terminal is to measure received signal strengths (or to estimate path losses), which capability is represented by "Rx level" in Table 1. Accordingly, in the second cellular RMDS of Table 1, in addition to coverage area models of the serving nodes, also radio channel models for the serving nodes are contained, which can be exploited in position estimation if received signal strengths (or path losses) can be determined by the mobile terminal. In the fourth cellular RMDS of Table 1, it is assumed that the mobile terminal is capable of identifying Cell IDs of serving nodes and also resources of neighboring nodes and to exploit information associated with the identified resources for determining a position estimate for the mobile terminal, and also to determine received signal strengths or pathlosses (for both the serving nodes and the neighboring nodes). Accordingly, the RMDS contains coverage area models and radio channel models for the serving and neighboring nodes. Furthermore, also for the fifth and sixth WLAN RMDSs, it is assumed that the mobile terminal is capable of measuring received signal strengths (or of estimating path losses), and therefore these RMDSs also comprise radio channel models for the WLAN APs.

For instance with respect to the WLAN (non-cellular) RMDSs, a further technical capability of the mobile terminal indicated by the fourth column of Table 1 is the capability to receive and process signals on frequency channels of one or two frequency bands of one or more WLAN systems. If the mobile terminal has this capability, the mobile terminals "sees" APs operating on two frequency bands, and accordingly, two coverage area models (one for each frequency band) can be included in a WLAN RMDS and accordingly exploited by the mobile terminal for positioning purposes. Therein, receiving and processing signals may for instance at least comprise receiving and processing (e.g. decoding) a broadcast signal containing an identification of a WLAN AP, so that the identification (e.g. a BSSID) becomes available for the mobile terminal, e.g. for positioning purposes.

The fifth ("Accuracy") and sixth ("Availability") columns of Table 1 respectively describe the respective accuracy and the availability of position estimates that are determined based on the different RMDSs listed in the rows of Table 1. The seventh column ("File size") finally gives a qualitative measure for the file size of the respective RMDSs.

It can thus for instance be seen from Table 1 that all four cellular RMDSs, which are exempla- rily assumed to pertain to the same geographical region here, for instance the region of a country as defined by an MCC, basically have the same availability (which is mainly determined by the number of serving nodes for which information is contained in the RMDS), but yield different position estimate accuracies, depending on the respective RMDS contents. Both accuracy and file size significantly increase from the first cellular RMDS to the last (fourth) cellular RMDS. It depends on the technical capabilities of the mobile terminal if these RMDS contents can actually be fully exploited for positioning purposes. It can also be seen that only the first two cellular RMDSs can be transferred via a cellular connection (while for the second cellular RMDS, it is advisable to have a "local" cellular connection in which the mobile terminal is not roaming), whereas the third and fourth RMDSs already require a WLAN connection to be transferred within an acceptable time and/or with acceptable costs.

The WLAN RMDSs, which are also assumed to pertain to the same geographical area, differ in both the spatial density of APs contained therein, the fact whether coverage area models for one or two frequency bands are included and the fact whether there are coverage area models only or both coverage area models and radio channel models for the WLAN APs. Again, accuracy and file size increase from the first WLAN RMDS to the last (sixth) WLAN RMDS. As can further be seen, the availability of the position estimate that can be determined based on the WLAN RMDSs depends on the spatial density of the APs. For the first two WLAN RMDSs, which have a "medium" spatial density, the availability is "good", while for the last four WLAN RMDSs, which have a "high" spatial density, the availability is "best". The spatial density is a measure for the number of APs per area element. An RMDS with a high spatial density of APs may for instance be turned in an RMDS with a medium spatial density by thinning out APs (i.e. the respective coverage area models and/or radio channel models) therefrom.

The cellular RMDSs and/or WLAN RMDSs may for instance be provided as files for download by mobile terminals (like mobile terminal 2 of Fig. 1) at a server, for instance RMDS server 4 of Fig. 1. Therein, each RMDS may for instance be represented by a single file, or by a compilation of several files.

In example embodiments of the present invention, the actual selection of the RMDSs that a mobile terminal can download from the plurality of available RMDSs may then for instance primarily be based on the columns "Connectivity type" (with exemplary values cellular (local or roaming), and WLAN) and "Required measurement support", denoting if the mobile terminal can measure neighbour cells, cellular Rx levels or if there is 2.4GHz and/or 5.0GHz WLAN AP support.

Therein, as an example, in case of WLAN connectivity, the file size of the RMDS to be obtained may not be a problem and may thus not particularly further affect the selection. In contrast, in case of cellular connectivity (local), the RMDSs with average file sizes may be obtainable but not excessively. Even further, in case of cellular connectivity with roaming, the file size of the RMDS to be obtained may be very limited in view of the associated costs. With respect to the generation of the cellular and/or WLAN RMDSs, the following is to be noted. In case of cellular RMDSs, the creation of the different RMDSs is rather straightforward, e.g. information on neighbor nodes (as "child" data sets to "parent" data sets if serving nodes) is either dropped or not, and similarly information on radio channel models is added to coverage area model information or not. In case of WLAN RMDSs, likewise whether to include coverage area model information for one or two coverage areas (one for 2.4GHz, the other for 5.0GHz) or one or two radio channel models (in addition to respective coverage area model information) is easy to implement. The spatial density of the WLAN APs can be varied by altering the number of APs per area element for which coverage area model information and/or radio channel information is included in the RMDS.

The selection of an RMDS to be downloaded may also be affected by the use case. For instance, in some cases the mobile terminal might have both cellular and WLAN radio support. Now, assume that the terminal needs to download an RMDS over a cellular network as the mobile terminal enters a new area. In this case, the mobile terminal could in principle download both cellular and WLAN RMDSs, but the device might decide to download only the cellular RMDS, because there's currently no need for a WLAN RMDS (e.g. because the only application currently using positioning is a weather application requiring 1 -km accurate position only).

In exemplary embodiments of the invention, the implementation may behave in such a way that in case where a small RMDS is downloaded for a given area over a cellular connection, then later on when the mobile terminal connects to the Internet over WLAN, the bigger RMDS (providing better availability and accuracy of the position estimate) for the area is downloaded automatically.

One criterion for selecting the RMDS to be downloaded to the mobile terminal can of course be the amount of storage space in the mobile terminal. If limited on space, then the mobile terminal can e.g. download only the cellular RMDS and not the WLAN RMDS at all.

Embodiments of the present invention thus achieve less burden for server resources, network resources and/or lower data costs to the consumer, when RMDSs are downloaded to the mobile terminal. In some example embodiments of the present invention, the RMDSs from the plurality of RMDSs from which the RMDS is selected all pertain to one or more cellular communication networks (as for instance the cellular RMDSs of Table 1 above), or all pertain to one or more non-cellular communication networks (as for instance the WLAN RMDSs of Table 1 above). There may thus for instance exist several RMDSs at least partially (or for instance entirely) pertaining to the same geographical region and pertaining to cellular communication networks only. Cellular communication networks may for instance be 2G, 3G or 4G cellular communication networks, such as for instance according to the Global System for Mobile Communication (GSM) or the Universal Mobile Telecommunication Standard (UMTS) or the Long Term Evolution (LTE) standard, to name but a few non-limiting examples. A non-limiting example of a non-cellular communication network is a WLAN communication network, for instance according to one or more of the IEEE 802.1 1 family of standards. If all RMDSs pertain to one or more cellular communication networks only, the mobile terminal information may for instance be different from or exceed a mere information that the mobile terminal is generally capable to receive and process signals from (e.g. communicate with, or at least to detect an identification of) one or more cellular communication networks and/or an information indicating the operator of these one or more cellular communication networks (e.g. the operator with which a user of the mobile terminal has a contract entitling the user to use the one or more cellular communication networks of the operator).

Alternatively, in some example embodiments of the present invention, at least one RMDS from the plurality of RMDSs pertains to one or more cellular communication networks, and at least one (for instance the same or another) RMDS from the plurality of RMDSs pertains to one or more non-cellular communication networks. In this case, the mobile terminal information may comprise an indication of one or more technical capabilities of the mobile terminal that is different from or exceeds a mere indication of the mobile terminal's capability to use an RMDS set pertaining to cellular-type communication networks, an RMDS pertaining to non- cellular-type communication networks e.g. WLAN-type communication networks) or an RMDS pertaining to both cellular-type and non-cellular-type communication networks. Thus in these embodiments, where the plurality of RMDSs pertains to both one or more cellular communication networks and one or more non-cellular communication networks, the mobile terminal information on which the selection of the RMDS to be obtained by/provided to the mobile terminal is based provides more information than the mere information on the mobile terminal's (general) capability to use an RMDS pertaining to cellular-type, non-cellular-type or both cellular-type and non-cellular-type communication networks. The mobile terminal information may thus for instance not be limited to a simple communication capability classifier like for instance "cellular" or "WLAN" (similar as in the first column of Table 1 above), but provide information in excess of that that can be exploited to select the RMDS from the plurality of RMDSs. For instance, the mobile terminal information may comprise information on whether the mobile terminal is capable of measuring a received signal strength and/or a pathloss, and/or is capable of measuring both a serving cell and neighboring cells of a cellular communication network, and/or is capable of receiving and processing signals on frequency channels of two different frequency bands of one or more (e.g. non-cellular-type) communication networks (e.g. on both a 2.4 and 5.0 GHz band of one or more IEEE 802.1 1 communication networks). Therein, an RMDS pertaining to a cellular-type communication network is for instance considered as an RMDS pertaining to at least one cellular communication network, and an RMDS pertaining to a non-cellular-type communication network is for instance considered as an RMDS pertaining to at least one non-cellular communication network.

In some example embodiments of the present invention, the plurality of RMDSs from which the RMDS obtained at the mobile terminal is selected based on the mobile terminal information may for instance be pre-selected based on information on a geographical region for which the RMDS is required/desired and/or based on information pertaining to a capability of the mobile terminal to use one or more RMDSs pertaining to one or more cellular communication networks only, to non-cellular communication networks only or to both cellular and non- cellular communication networks (see for instance the first column of Table 1 above) and/or based on information indicating an operator of the one or more cellular communication networks in which the mobile terminal is capable and entitled to receive and process signals (e.g. to communicate). This information may for instance also be available at and/or provided by the mobile terminal (for instance in step 602 of Fig. 6), for instance together with the mobile terminal information. The further selection of the RMDS from the plurality of RMDSs resulting from this pre-selection then is based on the mobile terminal information, which for instance characterizes further technical capabilities of the mobile terminal as already described above.

In the following, further features and example embodiments of the invention will be described, that equally pertain to the first method, first and third apparatus and first non- transitory computer readable storage medium according to the present invention and also to the second method, second and fourth apparatus and second non-transitory computer readable storage medium according to the present invention. For the sake of simplicity of presentation, some of these embodiments will be numbered, wherein this numbering shall however not imply a specific importance or shall not exclude any other embodiments in any way.

According to a first example embodiment of the present invention, at least one of the RMDSs comprises radiomap information useable for determining a position estimate for the mobile terminal and/or contributing to a quality of the position estimate for the mobile terminal only if the mobile terminal has at least one technical capability. Therein, non-limiting examples of the technical capability of the mobile terminal comprise at least one of a capability of the mobile terminal to identify, while communicating with a serving node of a cellular communication network, also at least respective resources of one or more neighboring nodes that are of the same or one or more other cellular communication networks and to exploit information associated with the identified resources for determining a position estimate for the mobile terminal, a capability of the mobile terminal to measure a received signal strength and/or to estimate a path loss, and a capability of the mobile terminal to receive and process signals (e.g. to communicate) on frequency channels of at least one frequency band (e.g. a specific or identified one) of at least two frequency bands of one or more communication networks (e.g. non-cellular communication networks), wherein the at least one frequency band of the at least two frequency bands on the channels of which the mobile terminal is able to receive and process signals is identified in the mobile terminal information.

According to a second example embodiment of the present invention, the first example embodiment has the further feature that at least one other of the RMDSs does not comprise the radiomap information.

It may then nevertheless for instance be the case that the at least one RMDS and the at least one other RMDS have some radiomap information in common that is useable for determining a position estimate for the mobile terminal and/or contributes to a quality of the position estimate for the mobile terminal even if the mobile terminal does not have the at least one technical capability.

An example of the at least one RMDS and the at least one other RMDS are the first two cellular RMDSs of Table 1 above, which at least share the coverage area model information, but do not share the radio channel model information, which is only present in the second RMDS and only contributes to a quality of the position estimate for the mobile terminal if the mobile terminal is capable of measuring received signal strengths and/or pathlosses. According to the first example embodiment of the present invention, the at least one RMDS may for instance only be considered for selection from the plurality of RMDSs if the mobile terminal information indicates that the mobile terminal has the at least one technical capability. Otherwise, the at least one RMDS may for instance be excluded from the plurality of RMDSs. The at least one RMDS being considered for selection may for instance be understood in a way that, from the plurality of RMDSs, the at least one RMDS is taken as a candidate for selection. Nevertheless, still another candidate may be selected based on further selection criteria, in particular based on further selection criteria contained in the mobile terminal information (such as for instance a maximum file size, and/or a type of a connection via which the selected RMDS is to be obtained, and/or a quality that is considered to be sufficient at the mobile terminal).

Therein, at least one other of the RMDSs may for instance not comprise the radiomap information, and the at least one other radiomap data may then for instance be considered for selection if the mobile terminal information does not indicate that the mobile terminal has the at least one technical capability or (e.g. actively) indicates that the mobile terminal does not have the at least one technical capability.

The at least one other RMDS may for instance be smaller in size than the at least one RMDS. It is advantageous in this case to select the (smaller) other RMDS, since the (larger) RMDS cannot be fully exploited by the mobile terminal anyway.

According to the first example embodiment of the present invention, the at least one RMDS may only be considered for selection from the plurality of RMDSs in one of the following two cases:

a) the mobile terminal information indicates that the mobile terminal has the at least one technical capability,

b) the mobile terminal information does not indicate that the mobile terminal has the at least one technical capability or indicates that the mobile terminal does not have the at least one technical capability, but the at least one RMDS comprises further radiomap information useable for determining a position estimate for the mobile terminal and/or contributing to a quality of the position estimate for the mobile terminal even if the mobile terminal does not have the at least one technical capability, and no other RMDSs of the plural- ity of RMDSs can be selected due to one or more restrictions indicated by the mobile terminal information.

The restrictions may for instance be a maximum file size, and/or a type of a connection via which the selected RMDS is to be obtained, and/or a quality that is considered to be sufficient at the mobile terminal

The at least one RMDS is thus for instance considered for selection (or even selected) even when the mobile terminal does not have the required technical capability, since the at least one RMDS comprises further radiomap information that can be used by the mobile terminal for positioning and since the at least one RMDS is the only candidate RMDS that fulfills further restrictions (e.g. selection requirements). Thus a potentially too large (i.e. partially non- exploitable) RMDS is nevertheless obtained by the mobile terminal to avoid that no RMDS is obtained by the mobile terminal at all.

According to the first example embodiment of the present invention, in the at least one RMDS, only the radiomap information, but no other information pertains to the at least one technical capability of the terminal.

According to the first example embodiment of the present invention, the at least one technical capability may for instance be a capability of the mobile terminal to receive and process signals (e.g. to communicate) on frequency channels of at least one (e.g. a specific and/or identified) frequency band of at least two frequency bands of one or more communication networks (e.g. non-cellular communication networks), wherein the at least one frequency band of the at least two frequency bands on the channels of which the mobile terminal is able to receive and process signals (e.g. to communicate) is identified in the mobile terminal information, and wherein the at least one RMDS pertains to the at least one frequency band and not to other frequency bands of the at least two frequency bands of the one or more communication networks. The at least two frequency bands of the one or more communication networks may for instance be a 2.4-2.4835 GHz frequency band and a 5.15-5.725 GHz frequency band of an IEEE 802.11 WLAN (non-cellular) communication network. Instead of indicating a general capability to receive and process (e.g. communicate via) WLAN signals, the mobile terminal may thus explicitly indicate if it is capable of receiving and processing WLAN signals on the first frequency band, the second frequency band or both (see the measurement requirements in the third column of Table 1 above for the six WLAN RMDSs, where it is differentiated be- tween 2.4 and/or 5.0 GHz WLAN support of the mobile terminal). The RMDS may then be selected accordingly.

Therein, the at least one radiomap data may for instance pertain to one frequency band of the at least two frequency bands only, and the plurality of RMDSs may for instance comprise at least one other RMDS that pertains to at least one other frequency band of the at least two frequency bands only or to both the first frequency band and the at least one other frequency band of the at least two frequency bands. There thus may for instance exist an RMDS for the first frequency band only, and a further RMDS for the second frequency band (or both the first and second frequency band). Equally well, there may exist respective RMDSs for the first frequency band, the second frequency band and both the first and the second frequency band, which are selected depending on the mobile terminals technical capabilities.

According to the first example embodiment of the present invention, the at least one technical capability is a capability of the mobile terminal to identify, in addition to a serving node of a cellular communication network, also at least respective resources of one or more neighboring nodes that are of the same or one or more other cellular communication networks and to exploit information associated with the identified resources (for instance together with further information) for determining a position estimate for the mobile terminal, and wherein the radiomap information comprises coverage area model information and/or radio channel model information for respective neighboring nodes of serving nodes of one or more cellular communication networks. An example of the at least one RMDS is the third cellular RMDS of Table 1 above. At least respective resources (e.g. radio or physical resources such as pilot signals, frequency channels, timeslots, spreading or scrambling codes, spatial channels, etc.) of neighboring nodes (with associated neighboring cells) are thus identified by the mobile terminal and used for positioning in addition to a serving cell (associated with a serving node). There may for instance be one or more resources per neighboring node. These resources may for instance be at least locally unique within the one or more communication networks and may thus, for instance together with the (e.g. globally unique) identifier of the serving cell, allow retrieving radiomap information (e.g. coverage area model information and/or radio channel model information) for the neighboring nodes from the at least one RMDS, which can be exploited for more accurately determining the position estimate for the mobile terminal.

For instance, the at least one RMDS may comprise coverage area model information and/or radio channel model information for the serving nodes. The information for the neighboring nodes may then for instance be subordinated (as "childs" to the information for the serving cells (the "parents"), respectively.

Equally well, as an alternative or and addition to identifying at least respective resources of one or more neighboring nodes of the one or more communication networks, the capability of the mobile terminal may be a capability to identify, in addition to the serving node of a cellular communication network, the one or more neighboring nodes, for instance in a globally unique sense, and to exploit information associated with the identified neighboring nodes for determining a position estimate for the mobile terminal.

According to the first example embodiment of the present invention, the at least one technical capability may for instance be a capability of the mobile terminal to measure a received signal strength and/or to estimate a path loss, and the radiomap information may for instance comprise radio channel model information for one or more nodes of one or more communication networks. An example of the at least one RMDS is the second cellular RMDS of Table 1 above. Measuring a received signal strength and/or estimating a pathloss may be a necessary technical capability of the mobile terminal to be able to exploit the radio channel model information comprised in the at least one RMDS for positioning.

According to the first example embodiment of the present invention, the at least one technical capability may for instance be a first capability of the mobile terminal to identify, in addition to a serving node of a cellular communication network, also at least respective resources of one or more neighboring nodes that are of the same or one or more other cellular communication networks and to exploit information associated with the identified resources for determining a position estimate for the mobile terminal, and a second capability of the mobile terminal to measure a received signal strength and/or to estimate a path loss, and the radiomap information may for instance comprise radio channel model information for serving nodes of one or more cellular communication networks and radio channel model information for respective neighboring nodes of the serving node. An example of the at least one RMDS is the fourth cellular RMDS of Table 1 above.

According to the second example embodiment of the invention, the at least one RMDS may for instance be larger in size than the at least one other RMDS of the RMDSs. The at least one RDMDs is thus for instance only selected from the plurality of RMDSs if the (additional) information contained therein can actually be exploited by the mobile terminal. This saves resources at the server where the RMDS is provided, in the network, via which the selected RMDS is provided to the mobile terminal and at the mobile terminal and also download costs for the user of the mobile terminal.

Therein, at least one of the RMDSs may for instance have a larger size than at least one other RMDS of the RMDSs because it comprises, in addition to a first radiomap data subset that is also contained in the other RMDS, one or more further radiomap data subsets that are not comprised in the other RMDS, each of the further radiomap data subsets contributing to a quality of the position estimate for the mobile terminal only if the mobile terminal has one or more respective technical capabilities related to the further radiomap data subset.

In a third example embodiment of the present invention, at least two of the RMDSs have different respective sizes at least due to different respective spatial densities of nodes of one or more non-cellular communication networks for which respective coverage area model information and/or radio channel information is contained in the at least two RMDSs. An example of such two RMDSs are the first and the third WLAN RMDSs of Table 1 above.

In a fourth example embodiment of the present invention, at least two of the RMDSs have different respective sizes at least because at least one of them pertains to nodes of one or more cellular communication networks only and at least one other of them pertains to nodes of one or more non-cellular communication networks only. Examples of such two RMDSs are the first cellular and the first WLAN RMDSs of Table 1 above.

According to the third and fourth example embodiments of the invention, the RMDSs with the respective different sizes may for instance allow for a different respective quality (for instance in terms of accuracy and/or availability) of a respective position estimate for a mobile terminal if determined at least based on the respective RMDSs. This is indicated in the last three columns of Table 1 above, where it can be seen how quality can be traded against different file sizes of the RMDSs.

In example embodiments of the present invention, at least two (or for instance even all) of the RMDSs have different respective sizes and thus allow for a different respective quality of a respective position estimate for a mobile terminal if determined at least based on the respective RMDSs. This is again indicated in the last three columns of Table 1 above. In a fifth example embodiment of the present invention, from the RMDSs, at least one RMDS is not selected, because information of the mobile terminal information indicates that obtaining the at least one RMDS at the mobile terminal is at least currently not possible, advisable or necessary.

The at least one RMDS may for instance be a RMDS that is considered for selection (for instance because the mobile terminal information indicates that the mobile terminal has a technical capability that is necessary to fully exploit the radiomap information contained in the at least one RMDS), but then is not selected due to the information of the mobile terminal information.

The at least one RMDS that is not selected may for instance have a larger size than the RMDS that is selected from the plurality of radio map data sets.

The information of the mobile terminal information may for instance comprise at least one of: an indication of a type and/or a transfer rate of a radio connection of the mobile terminal, via which the RMDS is to be obtained,

an indication of a maximum file size of the RMDS that is to be obtained,

an indication of a quality for the position estimate for the mobile terminal that is considered to be satisfactory at the mobile terminal.

According to the fifth example embodiment of the present invention, the mobile terminal information may for instance comprise an indication of a type and/or a transfer rate of a radio connection of the mobile terminal, via which the (selected) RMDS is to be obtained, and it may for instance be considered that obtaining the at least one RMDS is currently not advisable if it is considered that a transfer time of a transfer of the at least one RMDS to the mobile terminal via the radio connection would be too long and/or if it is considered that transfer costs of a transfer of the at least one RMDS to the mobile terminal via the radio connection would be too high.. It may for instance be considered that the transfer time is too long if the transfer time exceeds a pre-defined maximum transfer time. The transfer time may for instance be obtained by dividing the size of the at least one RMDS by the transfer rate of the radio connection. The pre-defined maximum transfer time may for instance be 1 , 2, 5 or 10 minutes, to give but a few examples. The pre-defined maximum transfer time may for instance be comprised in the mobile terminal information or may be otherwise known or provided to the entity that performs the selection of the at least one RMDS. Transfer costs may for instance be ob- tained by multiplying an indicator that represents the transfer costs per amount of data (e.g. 0.5 EUR per MByte) with the size of the at least one RMDS. It may for instance be considered that transfer costs are too high if the transfer costs exceed pre-defined maximum transfer costs. The pre-defined maximum transfer costs may for instance be 0.5, 1, 2 or 5 Euros, to give but a few examples. The transfer costs per amount of data may for instance also be comprised in the mobile terminal information or may be otherwise known or provided to the entity that performs the selection of the at least one RMDS. The pre-defined maximum transfer costs may also be comprised in the mobile terminal information or may be otherwise known or provided to the entity that performs the selection of the at least one RMDS.

According to the fifth example embodiment of the present invention, the mobile terminal information may comprise an indication of a maximum file size of the RMDS that is to be obtained, and it may be considered that obtaining the at least one RMDS is currently not possible if it is determined that a file size of the at least one RMDS would exceed the indicated maximum file size. The maximum file size may for instance relate to a remaining storage capacity of the mobile terminal and/or a storage capacity at the mobile terminal available for storing the obtained RMDS.

According to the fifth example embodiment of the present invention, the mobile terminal information may comprise an indication of a quality for the position estimate for the mobile terminal that is considered to be satisfactory at the mobile terminal, and it may be considered that obtaining the at least one RMDS is currently not necessary if it is determined that the at least one RMDS, if used to determine a position estimate for the mobile terminal, would lead to a position estimate for the mobile terminal with a quality exceeding the indicated quality.

In some example embodiments of the present invention, the selection of the RMDS from the plurality of RMDSs comprises the following steps, which are also illustrated in the flowchart of Fig. 7:

identifying the plurality of RMDSs (step 701 ),

if the mobile terminal information indicates a maximum file size of the RMDS that is to be obtained, excluding any RMDS from the plurality of RMDSs that has a size that exceeds the indicated maximum file size (step 702),

if the mobile terminal information indicates a type and/or a transfer rate of a radio connection of the mobile terminal, via which the RMDS is to be obtained, excluding any RMDS from the plurality of RMDSs causing a transfer time considered to be too long and/or causing transfer costs considered to be too high (step 703),

if one or more of the RMDSs comprise radiomap information contributing to a quality of a position estimate for the mobile terminal only if the mobile terminal has one or more respective technical capabilities and do not comprise further radiomap information useable for determining a position estimate for the mobile terminal and/or contributing to a quality of the position estimate for the mobile terminal even if the mobile terminal does not have the at least one technical capability, and if the mobile terminal information does not indicate that the mobile terminal has the at least one technical capability or indicates that the mobile terminal does not have the at least one technical capability, excluding the one or more RMDSs from the plurality of RMDSs (step 704), if one or more of the RMDSs comprise radiomap information contributing to a quality of a position estimate for the mobile terminal only if the mobile terminal has one or more respective technical capabilities and comprise further radiomap information useable for determining a position estimate for the mobile terminal and/or contributing to a quality of the position estimate for the mobile terminal even if the mobile terminal does not have the at least one technical capability, and if the mobile terminal information does not indicate that the mobile terminal has the at least one technical capability or indicates that the mobile terminal does not have the at least one technical capability, excluding the one or more RMDSs from the plurality of RMDSs, as long as not the last radio data set remaining is excluded (step 705),

if the mobile terminal information indicates a quality for the position estimate for the mobile terminal that is considered to be satisfactory at the mobile terminal, excluding any RMDS from the plurality of RMDSs considered to lead, if used to determine a position estimate for the mobile terminal, to a position estimate for the mobile terminal with a quality exceeding the indicated quality, as long as not the last radio data set remaining is excluded (706),

selecting, as the RMDS, a RMDS remaining from the plurality of RMDSs that is considered to lead, among the remaining RMDSs, to the position estimate with the highest quality (step 707).

Therein, the above if-clauses (corresponding to steps 702 to 705 of Fig. 7) shall be understood in a way that they are basically optional and only form part of the embodiment if according information is present in the mobile terminal information. Thus the above list of if-clauses may for instance only comprise two if-clauses, if only information pertaining to these two if- clauses is present in the mobile terminal information, but may for instance comprise all five if- clauses, if information pertaining to these five if-clauses is present in the mobile terminal information. The if-clauses shall thus not imply that in any case, some sort of checking for information related to the respective if-clause would be performed.

The sequence of the steps 702-706 of Fig. 7 is not mandatory, also other sequences are possible. As an example, the sequence of steps 705 and 706 may be interchanged.

Fig. 8 illustrates examples of tangible storage media that may for instance be used to implement program memory 21 of Fig. 2 and/or program memory 41 of Fig. 4. To this end, Fig. 8 displays a flash memory 80, which may for instance be soldered or bonded to a printed circuit board, a solid-state drive 81 comprising a plurality of memory chips (e.g. Flash memory chips), a magnetic hard drive 82, a Secure Digital (SD) card 83, a Universal Serial Bus (USB) memory stick 84, an optical storage medium 85 (such as for instance a CD-ROM or DVD) and a magnetic storage medium 86.

Any presented connection in the described embodiments is to be understood in a way that the involved components are operationally coupled. Thus, the connections can be direct or indirect with any number or combination of intervening elements, and there may be merely a functional relationship between the components.

Further, as used in this text, the term 'circuitry' refers to any of the following:

(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry)

(b) combinations of circuits and software (and/or firmware), such as: (i) to a combination of processor(s) or (ii) to portions of processor(s)/ software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone, to perform various functions) and

(c) to circuits, such as a microprocessor(s) or a portion of a microprocessor(s), that require software or firmware for operation, even if the software or firmware is not physically present.

This definition of 'circuitry' applies to all uses of this term in this text, including in any claims. As a further example, as used in this text, the term 'circuitry' also covers an implementation of merely a processor (or multiple processors) or portion of a processor and its (or their) accompanying software and/or firmware. The term 'circuitry' also covers, for example, a baseband integrated circuit or applications processor integrated circuit for a mobile phone.

Any of the processors mentioned in this text, in particular but not limited to processors 20 and 40 of Figs. 2 and 4, could be a processor of any suitable type. Any processor may comprise but is not limited to one or more microprocessors, one or more processor(s) with accompanying digital signal processor(s), one or more processor(s) without accompanying digital signal processor(s), one or more special-purpose computer chips, one or more field-programmable gate arrays (FPGAS), one or more controllers, one or more application-specific integrated circuits (ASICS), or one or more computer(s). The relevant structure/hardware has been programmed in such a way to carry out the described function.

Moreover, any of the actions described or illustrated herein may be implemented using executable instructions in a general-purpose or special-purpose processor and stored on a computer- readable storage medium (e.g., disk, memory, or the like) to be executed by such a processor. References to 'computer-readable storage medium' should be understood to encompass specialized circuits such as FPGAs, ASICs, signal processing devices, and other devices.

It will be understood that all presented embodiments are only exemplary, and that any feature presented for a particular exemplary embodiment may be used with any aspect of the invention on its own or in combination with any feature presented for the same or another particular exemplary embodiment and/or in combination with any other feature not mentioned. It will further be understood that any feature presented for an exemple embodiment in a particular category may also be used in a corresponding manner in an exemple embodiment of any other category.

Claims

1. A method performed by an apparatus that is one of a mobile terminal and a part thereof, the method comprising:

obtaining a radiomap data set selected from a plurality of radiomap data sets, each of said radiomap data sets at least partially pertaining to the same geographical area, said radiomap data set selected from said radiomap data sets at least based on mobile terminal information available at and/or provided by said mobile terminal.

2. A method performed by an apparatus, the method comprising:

storing a plurality of radiomap data sets, each of said radiomap data sets at least partially pertaining to the same geographical area, and

providing, to a mobile terminal, a radiomap data set selected from said plurality of radiomap data sets, said radiomap data set selected from said radiomap data sets at least based on mobile terminal information available at and/or provided by said mobile terminal.

3. The method according to any of the claims 1-2, wherein said mobile terminal information comprises at least one of:

an indication of a type and/or a transfer rate of a radio connection of said mobile terminal, via which said radiomap data set is to be obtained,

an indication of a maximum file size of said radiomap data set that is to be obtained, an indication of a quality for a position estimate for said mobile terminal that is considered to be satisfactory at said mobile terminal, wherein a position estimate for said mobile terminal is determinable at least based on said radiomap data set, and

an indication of at least one technical capability of said mobile terminal comprising at least one of

a capability of said mobile terminal to identify, in addition to a serving node of a cellular communication network, also at least respective resources of one or more neighboring nodes that are of the same or one or more other cellular communication networks and to exploit information associated with said identified resources for determining a position estimate for said mobile terminal,

a capability of said mobile terminal to measure a received signal strength and/or to estimate a path loss, and a capability of said mobile terminal to receive and process signals on frequency channels of at least one frequency band of at least two frequency bands of one or more communication networks, wherein said at least one frequency band of said at least two frequency bands on the channels of which said mobile terminal is able to receive and process signals is identified in said mobile terminal information.

4. The method according to any of the claims 1-3, wherein at least one of said radiomap data sets comprises radiomap information useable for determining a position estimate for said mobile terminal and/or contributing to a quality of said position estimate for said mobile terminal only if said mobile terminal has at least one technical capability.

5. The method according to claim 4, wherein at least one other of said radiomap data sets does not comprise said radiomap information.

6. The method according to claim 5, wherein said at least one radiomap data set and said at least one other radiomap data set have some radiomap information in common that is useable for determining a position estimate for said mobile terminal and/or contributes to a quality of said position estimate for said mobile terminal even if said mobile terminal does not have said at least one technical capability.

7. The method according to any of the claims 4-6, wherein said at least one radiomap data set is only considered for selection from said plurality of radiomap data sets if said mobile terminal information indicates that said mobile terminal has said at least one technical capability.

8. The method according to claim 7, wherein at least one other of said radiomap data sets does not comprise said radiomap information, and wherein said at least one other radiomap data set is considered for selection if said mobile terminal information does not indicate that said mobile terminal has said at least one technical capability or indicates that said mobile terminal does not have said at least one technical capability.

9. The method according to any of the claims 4-6, wherein said at least one radiomap data set is only considered for selection from said plurality of radiomap data sets in one of the following two cases: said mobile terminal information indicates that said mobile terminal has said at least one technical capability,

said mobile terminal information does not indicate that said mobile terminal has said at least one technical capability or indicates that said mobile terminal does not have said at least one technical capability, but said at least one radiomap data set comprises further radiomap information useable for determining a position estimate for said mobile terminal and/or contributing to a quality of said position estimate for said mobile terminal even if said mobile terminal does not have said at least one technical capability, and no other radiomap data sets of said plurality of radiomap data sets can be selected due to one or more restrictions indicated by said mobile terminal information.

10. The method according to any of the claims 4-9, wherein in said at least one radiomap data set, only said radiomap information, but no other information pertains to said at least one technical capability of said terminal.

11. The method according to any of the claims 4- 10, wherein said at least one technical capability is a capability of said mobile terminal to receive and process signals on frequency channels of at least one frequency band of at least two frequency bands of one or more communication networks, wherein said at least one frequency band of said at least two frequency bands on the channels of which said mobile terminal is able to receive and process signals is identified in said mobile terminal information, and wherein said at least one radiomap data set pertains to said at least one frequency band and not to other frequency bands of said at least two frequency bands of said one or more communication networks.

12. The method according to claim 1 1, wherein said at least one radiomap data set pertains to one frequency band of said at least two frequency bands only, and wherein said plurality of radiomap data sets comprises at least one other radiomap data set that pertains to at least one other frequency band of said at least two frequency bands only or to both said first frequency band and said at least one other frequency band of said at least two frequency bands.

13. The method according to any of the claims 4- 10, wherein said at least one technical capability is a capability of said mobile terminal to identify, in addition to a serving node of a cellular communication network, also at least respective resources of one or more neighboring nodes that are of the same or one or more other cellular communication networks and to exploit information associated with said identified resources for determining a position estimate for said mobile terminal, and wherein said radiomap information comprises coverage area model information and/or radio channel model information for respective neighboring nodes of serving nodes of one or more cellular communication networks.

14. The method according to claim 13, wherein said at least one radiomap data set also comprises coverage area model information and/or radio channel model information for said serving nodes.

15. The method according to any of the claims 4-10, wherein said at least one technical capability is a capability of said mobile terminal to measure a received signal strength and/or to estimate a path loss, and wherein said radiomap information comprises radio channel model information for one or more nodes of one or more communication networks.

16. The method according to any of the claims 4- 10, wherein said at least one technical capability is a first capability of said mobile terminal to identify, in addition to a serving node of a cellular communication network, also at least respective resources of one or more neighboring nodes that are of the same or one or more other cellular communication networks and to exploit information associated with said identified resources for determining a position estimate for said mobile terminal, and a second capability of said mobile terminal to measure a received signal strength and/or to estimate a path loss, and wherein said radiomap information comprises radio channel model information for serving nodes of one or more cellular communication networks and radio channel model information for respective neighboring nodes of said serving node.

17. The method according to any of claims 5, 6 and 8, wherein said at least one radiomap data set is larger in size than said at least one other radiomap data set of said radiomap data sets.

18. The method according to any of the claims 1-17, wherein at least two of said radiomap data sets have different respective sizes at least due to different respective spatial densi- ties of nodes of one or more non-cellular communication networks for which respective coverage area model information and/or radio channel information is contained in said at least two radiomap data sets.

19. The method according to any of the claims 1-18, wherein at least two of said radiomap data sets have different respective sizes at least because at least one of them pertains to nodes of one or more cellular communication networks only and at least one other of them pertains to nodes of one or more non-cellular communication networks only.

20. The method according to any of the claims 18-19, wherein said radiomap data sets with said respective different sizes allow for a different respective quality of a respective position estimate for a mobile terminal if determined at least based on said respective radiomap data sets.

21. The method according to any of the claims 1-20, wherein at least two of said radiomap data sets have different respective sizes and thus allow for a different respective quality of a respective position estimate for a mobile terminal if determined at least based on said respective radiomap data sets.

22. The method according to any of the claims 1-21, wherein, from said radiomap data sets, at least one radiomap data set is not selected, because information of said mobile terminal information indicates that obtaining said at least one radiomap data set at said mobile terminal is at least currently not possible, advisable or necessary.

23. The method according to claim 22, wherein said mobile terminal information comprises an indication of a type and/or a transfer rate of a radio connection of said mobile terminal, via which said radiomap data set is to be obtained, and wherein it is considered that obtaining said at least one radiomap data set is currently not advisable if it is considered that a transfer time of a transfer of said at least one radiomap data set to said mobile terminal via said radio connection would be too long and/or if it is considered that transfer costs of a transfer of said at least one radiomap data set to said mobile terminal via said radio connection would be too high.

24. The method according to claim 22, wherein said mobile terminal information comprises an indication of a maximum file size of said radiomap data set that is to be obtained, and wherein it is considered that obtaining said at least one radiomap data set is currently not possible if it is determined that a file size of said at least one radiomap data set would exceed said indicated maximum file size.

25. The method according to claim 22, wherein said mobile terminal information comprises an indication of a quality for said position estimate for said mobile terminal that is considered to be satisfactory at said mobile terminal, and wherein it is considered that obtaining said at least one radiomap data set is currently not necessary if it is determined that said at least one radiomap data set, if used to determine a position estimate for said mobile terminal, would lead to a position estimate for said mobile terminal with a quality exceeding said indicated quality.

26. The method according to any of claims 1-25, wherein selection of said radiomap data set from said plurality of radiomap data sets comprises:

identifying said plurality of radiomap data sets,

if said mobile terminal information indicates a maximum file size of said radiomap data set that is to be obtained, excluding any radiomap data set from said plurality of radio- map data sets that has a size that exceeds said indicated maximum file size, if said mobile terminal information indicates a type and/or a transfer rate of a radio connection of said mobile terminal, via which said radiomap data set is to be obtained, excluding any radiomap data set from said plurality of radiomap data sets causing a transfer time considered to be too long and/or causing transfer costs considered to be too high,

if one or more of said radiomap data sets comprise radiomap information contributing to a quality of a position estimate for said mobile terminal only if said mobile terminal has one or more respective technical capabilities and do not comprise further radiomap information useable for determining a position estimate for said mobile terminal and/or contributing to a quality of said position estimate for said mobile terminal even if said mobile terminal does not have said at least one technical capability, and if said mobile terminal information does not indicate that said mobile terminal has said at least one technical capability or indicates that said mobile terminal does not have said at least one technical capability, excluding said one or more radiomap data sets from said plurality of radiomap data sets,

if one or more of said radiomap data sets comprise radiomap information contributing to a quality of a position estimate for said mobile terminal only if said mobile terminal has one or more respective technical capabilities and comprise further radiomap information useable for determining a position estimate for said mobile terminal and/or contributing to a quality of said position estimate for said mobile terminal even if said mobile terminal does not have said at least one technical capability, and if said mobile terminal information does not indicate that said mobile terminal has said at least one technical capability or indicates that said mobile terminal does not have said at least one technical capability, excluding said one or more radiomap data sets from said plurality of radiomap data sets, as long as not the last radio data set remaining is excluded, if said mobile terminal information indicates a quality for a position estimate for said mobile terminal that is considered to be satisfactory at said mobile terminal, excluding any radiomap data set from said plurality of radiomap data sets considered to lead, if used to determine a position estimate for said mobile terminal, to a position estimate for said mobile terminal with a quality exceeding said indicated quality, as long as not the last radio data set remaining is excluded, and

selecting, as said radiomap data set, a radiomap data set remaining from the plurality of radiomap data sets that is considered to lead, among the remaining radiomap data sets, to the position estimate with the highest quality.

27. The method according to any of claims 1-26, wherein said radiomap data set is selected by an apparatus that obtains said radiomap data set or by another apparatus that is either an apparatus that provides said radiomap data set or an apparatus that is associated with said apparatus that provides said radiomap data set.

28. The method according to any of claims 1-27, wherein a position estimate for said mobile terminal is determinable [e.g. at said mobile terminal, e.g. by said apparatus] based on said radiomap data set. Method may comprise determining a position estimate for said mobile terminal at least based on said radiomap data set.

29. The method according to any of claims 1-28, wherein said radiomap data set is requested by said mobile terminal. Method may comprise requesting radiomap data set. Request may contain mobile terminal information and/or information on geographical area.

30. The method according to any of claims 1-29, wherein said radiomap data set comprises at least one of respective coverage area model information and radio channel model information of one or more nodes of one or more communication networks.

31. The method according to claim 30, wherein a position estimate for said mobile terminal is determined at least based on respective coverage area model information and/or radio channel model information of one or more identified nodes of said one or more communication networks in a proximity of said mobile terminal.

32. The method according to any of the claims 1-31, wherein said obtaining or said providing of said radiomap data set is triggered by one of

an entry of said mobile terminal into or an activation of said mobile terminal in a geographical area for which no radiomap data set is available at said mobile terminal, a change of at least a part of said mobile terminal information,

a decision that an available radiomap is outdated.

33. A computer program code, the computer program code when executed by a processor causing an apparatus to perform the actions of the method of any of claims 1-32.

34. A computer readable storage medium in which computer program code according to claim 33 is stored.

35. An apparatus configured to realize or comprising respective means for realizing the method of any of the claims 1-32.

36. An apparatus comprising at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause an apparatus at least to perform the method of any of the claims 1-32.