CA2474140A1 - Method and apparatus for auxiliary pilot signal for mobile phone location - Google Patents

Method and apparatus for auxiliary pilot signal for mobile phone location Download PDF

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Publication number
CA2474140A1
CA2474140A1 CA002474140A CA2474140A CA2474140A1 CA 2474140 A1 CA2474140 A1 CA 2474140A1 CA 002474140 A CA002474140 A CA 002474140A CA 2474140 A CA2474140 A CA 2474140A CA 2474140 A1 CA2474140 A1 CA 2474140A1
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Prior art keywords
mobile unit
arrival
time
base
pilot signal
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CA002474140A
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French (fr)
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John Sabat Jr.
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Opencell Corp
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Individual
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Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W64/00Locating users or terminals or network equipment for network management purposes, e.g. mobility management
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B7/00Radio transmission systems, i.e. using radiation field
    • H04B7/24Radio transmission systems, i.e. using radiation field for communication between two or more posts
    • H04B7/26Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
    • H04B7/2603Arrangements for wireless physical layer control
    • H04B7/2606Arrangements for base station coverage control, e.g. by using relays in tunnels
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W16/00Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
    • H04W16/24Cell structures
    • H04W16/26Cell enhancers or enhancement, e.g. for tunnels, building shadow

Abstract

At repeaters or at each individual unit of a distributed antenna system, an auxiliary pilot signal is transmitted in addition to a common base station pilot signal to mobile units. The auxiliary pilot signal is unique to each repeater and each individual unit of the distributed antenna system within a local propagation area. A mobile unit measures the auxiliary pilot signals received from the repeater or distributed antenna units in the same manner it measures those of any base station pilot signal. The location of the mobile unit can be determined using well-known triangulation techniques based on the auxiliary pilot signal measurements.

Description

FOR MOBILE PHONE LOCATION
BACKGROUND
fit wireless cornmwication systems, base stations communicate with mobile phone units using standardized radio frequency protocols. To establish and control commwlication between the mobile phone unit and the base station, the base station uses a forward linl~ pilot signal, also refeiTed to as a control channel. In a code division multiple access (CDMA) system the pilot signal typically uses a pseudo-noise (PN) offset. In time division multiple access (TDMA) systems, a particular frequency and color code are used to characterize the pilot signal. Color code refers to an identification code that distinguishes one base station from another and is usually embedded with the pilot signal. The pilot signals are specified per base station according to a re-use plan common to the particular wireless protocol.
With increased demands for personal safety and security in today's society, wireless service providers are begirming to deploy mobile phone location capabilities. The ability to pinpoint the location of a mobile phone can be provided using well-Imown triangulation techniques based on relative timing of signals received from tluee sources having l~no~m locations. Particular techniques developed for the wireless industry include enhanced obsel-ved time difference (E-OTD), advanced forward lint trilateration (AFLT) and observed time difference of arrival (OTDOA).
One of the teclmiques for locating mobile units is based upon timing measurement of the base stations forward linlc pilot signal, used in CDMA and wide-band CDMA systems, or digital control channel (DCCH), used in TDMA/GSM
systems. The mobile unit measures the timing of these signals from multiple base
-2-station sites to compute multiple time difference of arrival (TDOA) hyperbolas, the intersection of which identifies the mobile unit location.
The pilot/DCCH signals are unique for each sector of each base station that is received by the mobile unit. The uniqueness of these signals (i.e., PN
offset for S CDMA, frequency and color code for TDMA) allows the mobile unit to separately measure each sector's timing.
SUMMARY
Repeaters and distributed antenna systems present a unique challenge to location measurement. Such systems replicate the source base station's signal and re-translnit that signal, either from the repeater's secondary location in a repeater-based system, or from multiple locations in the case of a distributed antenna system.
Thus, there can be conditions where a mobile unit receives multiple replicas of a single base station sector from multiple radiating source locations. The mobile unit 1 S may be able to measure the signal from the dominant source (either the host tower or the repeater) depending upon the mobile unit's relative location and local radio frequency (RF) propagation conditions. However, neither the mobile unit, nor a location server (if used) is able to compute a non-ambiguous solution.
The above and other problems are solved by the present approach which is directed to an auxiliary pilot capability.
At repeaters or at each individual unit of a distributed antenna system, an auxiliary pilot signal is transmitted in addition to the common base station pilot signal to mobile units. The auxiliary pilot signal is unique to each repeater and each individual emit of the distributed antenna system within a local propagation area.
2S Selection and assignment of the unique auxiliary pilot parameters (e.g., PN
offset for CDMA, frequency and color code fox TDMA/GSM) preferably follows the usual PN
offset/frequency re-use plan of the particular wireless networlc, though other assigmnent plans can be used.
A method of determining location of a mobile tulit in a wireless communication system includes transmitting a common base pilot signal from a base station to plural radio access nodes; transmitting auxiliary pilot signals and the
-3-common base pilot signal from the radio access nodes, each auxiliary pilot signal having differing signaling parameters; at a mobile unit, receiving the pilot signals and measuring time of arrival of the received pilot signals to provide time of arrival measurements; and determining a location of the mobile unit from the time of arrival measurements.
In an embodiment, the auxiliary pilot signals are generated at a centralized hub location, added to other data streams that include the common base station pilot signal and transmitted to the repeater or units of a distributed antenna system. In another embodiment, the auxiliary pilot sig~lal is generated locally at the repeater or at each unit of the distributed antenna system.
In operation with the present approach, a mobile unit that has been generally adapted to provide mobile location capabilities can simply measure the unique auxiliary pilot signals received from the repeater or distributed antenna outs in the same manner it measures those of any base station pilot signal. Accordingly, each pilot signal measurement is associated with a unique geographical location corresponding to a repeater or distributed antenna unit. From the pilot measurements, multiple TDOA hyperbolas are able to be computed, with the location of the mobile unit determined from the intersection of the TDOA
hyperbolas. These measurements can also be combined with those for conventional base stations (i.e., without repeaters or distributed anteima units).
The auxiliary pilot signal is not intended for use in call processing (other than location measurements) or as a destination for call hand-off. Since the cormnon base station pilot signal is still replicated and used for call processing, it needs to be omitted from any mobile unit location computation solutions to eliminate location ambiguities. To simplify implementation of the mobile unit, the usual raw pilot measurements associated with the common base station pilot signals are performed by the mobile unit along with those performed for the auxiliary pilot signals.
However, a location server can be programmed to consider only those measurements associated with the auxiliary pilot signals and to ignore the measurements for the common base station pilot signals. In other embodiments, mobile units can be
-4-further adapted to either only perform measurements for the auxiliary pilot signals or to ignore the measurements for the common base station pilot signals.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings in which lilce reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
FIG. 1 illustrates a traditional wireless network approach to mobile phone location.
FIG. 2 illustrates a wireless network configuration for which mobile phone location is not possible due to transmission of common pilot signals from a base station/repeater pair.
FIG. 3 shows a wireless network configuration for which mobile phone location is not possible due to simulcasting of the same pilot signal from distributed antenna nodes.
FIG. 4 illustrates a configuration for a repeater that provides a mobile phone location capability according to the present approach.
FIG. 5 shows a configuration for a distributed antenna system that provides a mobile phone location capability in accordance with the principles of the present approach.
FIG. 6 illustrates a wireless network configured in accordance with the present approach.
FIG. 7 is a block diagram of hub equipment adapted according to the principles of the present approach.
FIG. 8 is a block diagram of radio access node equipment adapted according to the principles of the present approach.
DETAILED DESCRIPTION
-5-FIG. 1 shows the traditional triangulation approach for determining the location of a mobile unit in a wireless communication system. In operation, a mobile unit 12 receives different pilot signals (pilot 1, pilot 2, pilot 3) from base stations 10-1; 10-2, 10-3, respectively. The mobile unit measures the timing of these signals received from the base stations to compute TDOA hyperbolas 22, 24.
Hyperbola 22 is based on measurements of pilot signals 2 and 3. Likewise, hyperbola 24 is based on measurements of pilot signals 1 and 2. The intersection of hyperbolas 22, 24 at point 23 identifies the location of the mobile unit. The location computations can be performed by the mobile unit itself, or the measurements can be relayed over network 152 to location server 154 to perform the computations.
FIG. 2 shows an example of a configuration in which location is not able to be determined because of ambiguity introduced by a tower/repeater pair. In the configuration, mobile unit 12 receives pilot signals from base stations 10-l, 10-2, 10-3. As shown, signals from base station 10-1 are re-transmitted from repeater 40.
Thus, the mobile unit also receives a replicated and delayed pilot signal 1 from repeater 40. A TDOA hyperbola 26 can be determined based on measurements of pilot signals 2 and 3. However, measurement of the two versions of pilot signal 1 from base station 10-1 and from repeater 40 yields two possible hyperbolic curves 28, 30. In addition, a meaungful TDOA hyperbola 32 is not possible between base station 10-1 and repeater 40. The result is that there are two ambiguous mobile locations 25, 27 as possible solutions. The ambiguity may be further compounded by the presence of multiple repeaters, distributed antennas, and multiple base station sectors.
There can also be conditions where a mobile unit only receives multiple replicas of a single base station sector. This readily occurs with a distributed antenna or a base station source hosting multiple repeaters. Under these conditions, no TDOA solution is possible. Under other circumstances, even a timing measurement may not be possible if no one signal source (tower or repeater) is able to dominate the mobile unit's receiver. FIG. 3 illustrates an example distributed antenna system for which TDOA measurement is not possible. In this configuration, base station 50 hosts distributed radio access nodes R.AN1, RAN2, RAN3, RAN4
-6-indicated at 54-l, 54-2, 54-3, 54-4, respectively over transport fiber 52. The base station 50 simulcasts the same signals to each radio access node. Since each radio access node transmits replicated pilot sig~~al l, determination of TDOA
hyperbolas 56, S8, 60 is not possible.
FIG. 4 illustrates a configuration for a repeater that provides a mobile phone location capability according to the present approach. The configuration shows a mobile unit 12 in communication with base stations 10-1, 10-2, 10-3 and a repeater 40 that repeats signals received from base station 10-1. Each base station has its own pilot signal. In this approach, an auxiliary pilot signal R is generated and added to the base station pilot signal 1 at repeater 40. Pilot signal 1 is received at the mobile unit from both base station 1 and the repeater but is not used to provide a solution to the location determination. Rather, the auxiliary pilot signal R
is used in conjunction with base station pilot signals 2 and 3 as a basis for TDOA
measurements. In particular, TDOA hyperbola 27 can be determined based on 1 S measurements of pilot signal 3 and auxiliary pilot signal R. Lilcewise, TDOA
hyperbola 29 can be determined from pilot signal 2 and auxiliary pilot signal R. The intersection of hyperbolas 27, 29 at point 31 identifies the location of the mobile unit. As with the traditional approach (FIG. 1) described above, the location computations can be performed by the mobile unit itself, or the measurements can be relayed over network 152 to location server 154 to perform the computations.
FIG. 5 shows a configuration for a distributed antenna system that provides a mobile phone location capability in accordance with the principles of the present appr, oach. The configuration shows a mobile unit 12 in communication with distributed antenna units or radio access nodes RANT, RAN2, RAN3, RAN4 indicated at 54-1, 54-2, 54-3, 54-4, respectively. W this approach, unique auxiliary pilot signals Rl, R2, R3, R4 are generated and added to the base station pilot signal 1 at each radio access node. The mobile unit uses the auxiliary pilot signals R1, R2, R3, R4 as a basis for TDOA measurements and can ignore the base station pilot signal 1. In particular, TDOA hyperbola 59 can be determined from measurements of auxiliary pilot signals R1 and R2. Likewise, TDOA hyperbolas 61 and 63 can be determined based on auxiliary pilot signal pairs R2, R3 and R3, R4, respectively.
7 PCT/US03/02665 Note that pilot 1 is not used for determining any TDOA contours. The intersection of hyperbolas 59, 61, 63 at point 33 identifies the location of the mobile unit. The location computations can be performed at the mobile unit or at location server 154.
In a particular embodiment, the present approach can be implemented using OpenCell equipment provided by Transcept OpenCell, W c., of Manchester, New Hampshire, assignee of the present application, and as described in co-pending U.S.
Patent Application No. 09/818,986, filed on March 27, 2001, entitled "Multi-Protocol Distributed Wireless System Architecture", which is incorporated herein by reference in its entirety. FIG. 6 illustrates a wireless network configured in accordance with the present approach. The configuration includes base stations BTS-1 to BTS-M 120, the OpenCell hub conversion equipment referenced above and indicated at 35A, SONET distribution 130, and RAN network 150. The hub conversion equipment is adapted to include auxiliary pilot signal generators 103 and is described further herein.
FIG. 7 is a block diagram of the hub equipment of FIG. 6 adapted for the present approach. Such a system includes a base station interface 35 located at a central hub location that converts radio frequency signals associated with multiple base stations 120, of the same or even different wireless service providers, to and from a transport signaling format. A shared transport medium, such as a SONET
data network or the like, is then used for transporting the converted signals from the hub location to a number of remote access node locations.
In such a configuration, signal down converter modules 100 convert the radio frequency signals associated with each base station to an Internediate Frequency (IF) signal. Associated analog to digital (A/D) modules 102 convert the Intermediate Frequency signals to digital signals suitable for handling by a transport formatter 108 that formats the converted digital signals to the proper framing format for the SONET digital transport as described in Application No. 09/818,986.
In the particular adaptation of the hub equipment 35 for the present approach, auxiliary pilot signals, one per RAN, are generated digitally within the centralized hub using auxiliary pilot signal generators 103. At summing nodes 105 the auxiliary pilot signals are digitally added into the data streams which are sent to each RAN

_g_ from simulcast modules 104 through reconfigurable interconnect 106. Note that in the configuration shown there are three sets of N pilot generators, one per R.AN in simulcast, one set per sector. For purposes of clarity, only the forward signal path is shown.
Even though the RANs are simulcast (that is, the same BTS signals simulcast to multiple RANs), the system is organized as multiple point to point digital links from the hub to each RAN. Generating the auxiliary pilot signals within the hub in this embodiment eliminates the hardware impact of generating the pilots within the RAN itself.
In another embodiment, the auxiliary pilot signals are digitally generated locally at each RAN and added digitally to the digital data streams received at the RAN. FIG. 8 shows a block diagram of radio access node equipment adapted for such an approach. The RANs are each associated with a particular coverage area.
The RANs include equipment that converts the radio signals required for a particular service provider to and from the transport signaling format received at SONET
modules 108. In particular, auxiliary pilot signals from signal generators 123 are summed with the received digital data streams at summing nodes 109. Associated digital to analog (D/A) modules 110 convert the digital signals to Intermediate Frequency signals suitable for upconversion to RF signals in converters 112.
The RF signals are amplified and distributed through RF feed network 117 in the manner described in Application No. 09/818,986. Return signals from the antennas are processed also in the manner described in Application No. 09/818,986. Note that in this particular embodiment which serves up to eight (8) tenants from the RAN, up to eight (8) pilot signal generators 123 are used (one per tenant).
In other embodiments, the auxiliary pilot signal can be generated within each RAN, converted it to IF/RF and summed with the existing IF/RF signals at the RAN.
For CDMA, an alternative mechanism for generating N pilots is the explicit generation of a single reference pilot replicated N times, each with a delay equal to that needed to generate the desired PN offset from the reference pilot.

It is possible for CDMA to measure time delay differences between the base station and its repeaters) provided relative path delays are greater than chip duration. In actuality, the delayed pilot must have a time offset greater than the longest multipath in the enviromnent to male it distinguishable from multipath.
Mobile unit software then can be modified to male this measurement. Note that this approach is coupled to the need for larger search windows for call processing.
It should be understood that any of the approaches for generating the auxiliary pilot signals described herein can also be implemented in repeater based systems.
With any of the approaches described above for generating auxiliary pilot signals, a mobile unit generally adapted for location capabilities (e.g., E-OTD, AFLT, OTDOA) can be used. The present approach can also be combined to augment assisted GPS mobile phone location when the mobile is unable to "see"
enough satellites for a GPS-only location solution. Timing measurements in accordance with the present approach can be combined with satellite timing measurements to generate a location solution.
The additional transmit power associated with the addition of an auxiliary pilot signal can be accommodated by performing any of the following: 1) increasing the power amplifier capabilities in the repeaters and distributed antenna units; 2) reducing the power for each traffic channel in order to free up power for the auxiliary pilot signal, thus reducing coverage; 3) reducing the number of simultaneous traffic channels (i.e., capacity). The power levels for the auxiliary pilots can be different from that of the base station pilots to either a) minimize power amplifier burden by using low level settings or b) increase auxiliary pilot overlap by using high Ievel settings.
For coverage and/or capacity reductions, the auxiliary pilot signal can be made active all the time or only activated when a mobile unit needs to be located in the region of the repeater or distributed antenna unit. The latter limits power reduction and signal interference to short term events, which if they occur during non-peak traffic will not affect call capacity on the sectors) involved.
Similarly, for coverage, the sector will not be affected if no mobile ants are operating at the limit of the liuc budget during the mobile location operation.
While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those spilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.

Claims (52)

What is claimed is:
1. A wireless communication system for determining location of a mobile unit, the system comprising:
plural wireless base stations each transmitting a base pilot signal having signaling parameters that are different for each base station;
a repeater receiving a corresponding base pilot signal from one of the plural base stations and transmitting a repeated base pilot signal and an auxiliary pilot signal having signaling parameters that differ from those of the base pilot signals;
a mobile unit receiving the base pilot signals from the plural base stations and receiving the repeated base pilot signal and the auxiliary pilot signal from the repeater, the mobile unit measuring time of arrival of received pilot signals to provide time of arrival measurements; and means for determining location of the mobile unit from the time of arrival measurements and from information defining locations of the base stations and the repeater.
2. The system of claim 1 wherein the means for determining location of the mobile unit considers time of arrival measurements corresponding to the non-repeated base pilot signals and the auxiliary pilot signal and ignores the time of arrival measurement corresponding to the repeated base pilot signal.
3. The system of claim 1 wherein the mobile unit is adapted to provide time of arrival measurements only for the non-repeated base pilot signals and the auxiliary pilot signal.
4. The system of claim 1 wherein the mobile unit is adapted to ignore time of arrival measurements for the repeated base pilot signal.
5. The system of claim 1 wherein the means for determining location of the mobile unit is included in the mobile unit.
6. The system of claim 1 wherein the means for determining location of the mobile unit comprises a location server connected to at least one of the plural base stations that receives the time of arrival measurements from the mobile unit.
7. The system of claim 1 wherein the mobile unit is adapted to measure time of arrival based on any of enhanced observed time difference (E-OTD), advanced forward link trilateration (AFLT), and observed time difference of arrival (OTDOA) techniques.
8. The system of claim 1 wherein time of arrival measurements associated with the auxiliary pilot signal are combined with assisted global positioning system measurements.
9. The system of claim 1 further including an auxiliary pilot signal generator for generating the auxiliary pilot signal.
10. The system of claim 1 further including an auxiliary pilot signal generator located with the repeater for generating the auxiliary pilot signal.
11. A wireless communication system for determining location of a mobile wut, the system comprising:
a wireless base station transmitting a base pilot signal;
plural radio access nodes coupled to the base station in a distributed configuration, each of the radio access nodes transmitting a replicated base pilot signal and an auxiliary pilot signal having signaling parameters that are different for each radio access node;
a mobile unit receiving the replicated base pilot signals and the auxiliary pilot signals from the radio access nodes, the mobile unit measuring time of arrival of received pilot signals to provide time of arrival measurements; and means for determining a location of the mobile unit from the time of arrival measurements and from information defining locations of the radio access nodes.
12. The system of claim 11 wherein the means for determining location of the mobile unit considers time of arrival measurements corresponding to the auxiliary pilot signals and ignores the time of arrival measurements corresponding to the replicated base pilot signals.
13. The system of claim 11 wherein the mobile unit is adapted to provide time of arrival measurements only for the auxiliary pilot signals.
14. The system of claim 11 wherein the mobile unit is adapted to ignore time of arrival measurements for the replicated base pilot signals.
15. The system of claim 11 wherein the means for determining location of the mobile unit is included in the mobile unit.
16. The system of claim 11 wherein the means for determining location of the mobile unit comprises a location server connected to the base station that receives the time of arrival measurements from the mobile unit.
17. The system of claim 11 wherein the mobile unit is adapted to measure time of arrival based on any of enhanced observed time difference (E-OTD), advanced forward link trilateration (AFLT), and observed time difference of arrival (OTDOA) techniques.
18. The system of claim 11 wherein time of arrival measurements of the auxiliary pilot signals are combined with assisted global positioning system measurements.
19. The system of claim 11 further including an auxiliary pilot signal generator that generates the respective auxiliary pilot signals by replicating a reference pilot, each replicated reference pilot having a respective delay to provide a desired PN offset.
20. The system of claim 11 further including at least one auxiliary pilot signal generator for generating the respective auxiliary pilot signals.
21. A wireless communication system for determining location of a mobile unit, the system comprising:
a wireless base station located at a hub location, the base station transmitting radio frequency signals including a base pilot signal;
a base station interface located at the hub, the base station interface converting the radio frequency signals associated with the base station to a transport signaling format;
a shared transport medium transporting the converted radio frequency signals from the hub location to plural remote access node locations;
plural radio access nodes located at the remote access node locations and coupled to receive signals from the shared transport medium, the radio access nodes each associated with a particular portion of a total system coverage area, the radio access nodes each comprising equipment converting from the transport signaling format to radio frequency signals and transmitting the radio frequency signals including the base pilot signal and an auxiliary pilot signal having signaling parameters that are different for each radio access node;
a mobile unit receiving the base pilot signals and the auxiliary pilot signals from the radio access nodes, the mobile unit measuring time of arrival of received pilot signals to provide time of arrival measurements; and means for determining a location of the mobile unit from the time of arrival measurements and from information defining locations of the radio access nodes.
22. The system of claim 21 wherein the shared transport medium is an optical fiber.
23. The system of claim 21 wherein the shared transport medium uses SONET
formatting.
24. The system of claim 21 wherein the means for determining location of the mobile unit considers time of arrival measurements corresponding to the auxiliary pilot signals and ignores the time of arrival measurement corresponding to the base pilot signals.
25. The system of claim 21 wherein the mobile unit is adapted to provide time of arrival measurements only for the auxiliary pilot signals.
26. The system of claim 21 wherein the mobile unit is adapted to ignore time of arrival measurements for the base pilot signals.
27. The system of claim 21 wherein the means for determining location of the mobile unit is included in the mobile unit.
28. The system of claim 21 wherein the means for determining location of the mobile unit comprises a location server connected to the base station that receives the time of arrival measurements from the mobile unit.
29. The system of claim 21 wherein the mobile unit is adapted to measure time of arrival based on any of enhanced observed time difference (E-OTD), advanced forward link trilateration (AFLT), and observed time difference of arrival (OTDOA) techniques.
30. The system of claim 21 wherein time of arrival measurements of the auxiliary pilot signals are combined with assisted global positioning system measurements.
31. The system of claim 21 further including an auxiliary pilot signal generator located at each remote access node location for generating the respective auxiliary pilot signals.
32. The system of claim 21 further including at least one auxiliary pilot signal generator located at the hub location for generating the respective auxiliary pilot signals.
33. A method of determining location of a mobile unit in a wireless communication system, the method comprising:
transmitting radio frequency signals including a base pilot signal from a wireless base station located at a hub location;
converting the radio frequency signals associated with the base station to a transport signaling format;
transporting the converted radio frequency signals from the hub location to plural remote access node locations over a shared transport medium;
receiving signals from the shared transport medium at plural radio access nodes located at the remote access node locations, the radio access nodes each associated with a particular portion of a total system coverage area;
at each radio access node, converting from the transport signaling format to radio frequency signals and transmitting the radio frequency signals including the base pilot signal and an auxiliary pilot signal having signaling parameters that are different for each radio access node;
at a mobile unit, receiving the base pilot signals and the auxiliary pilot signals, and measuring time of arrival of received pilot signals to provide time of arrival measurements; and determining a location of the mobile unit from the time of arrival measurements and from information defining locations of the radio access nodes.
34. The method of claim 33 wherein determining location of the mobile unit includes considering time of arrival measurements corresponding to the auxiliary pilot signals and ignoring the time of arrival measurement corresponding to the base pilot signals.
35. The method of claim 33 wherein measuring time of arrival includes measuring time of arrival only for the auxiliary pilot signals.
36. The method of claim 33 wherein measuring time of arrival includes ignoring time of arrival measurements for the base pilot signals.
37. The method of claim 33 wherein measuring time of arrival is based on any of enhanced observed time difference (E-OTD), advanced forward link trilateration (AFLT), and observed time difference of arrival (OTDOA) techniques.
38. The method of claim 33 further including generating the respective auxiliary pilot signals at each remote access node location or at the hub location.
39. The method of claim 33 further including generating the respective auxiliary pilot signals by replicating a reference pilot, each replicated reference pilot having a respective delay to provide a desired PN offset.
40. The method of claim 33 further including generating a particular auxiliary pilot signal only when the mobile unit needs to be located in the portion of the coverage area corresponding to the radio access node.
41. The method of claim 33 further including generating the auxiliary pilot signals to have increased power levels with respect to base pilot power levels to thereby increase auxiliary pilot coverage overlap.
42. The method of claim 33 further including generating the auxiliary pilot signals to have decreased power levels with respect to base pilot power levels to thereby reduce power amplifier requirements and signal interference.
43. A method of determining location of a mobile unit in a wireless communication system, the method comprising:
transmitting pilot signals from plural wireless nodes, the pilot signals each having differing signaling parameters and including at least one base pilot signal and at least one auxiliary pilot signal, transmitting further including transmitting one of the at least one base pilot signals from one of the plural nodes to at least one other of the plural nodes, and for the at least one other node, transmitting one of the at least one auxiliary pilot signals and the corresponding one of the at least one base pilot signals;
at a mobile unit, receiving the pilot signals and measuring time of arrival of the received pilot signals to provide time of arrival measurements;
and determining a location of the mobile unit from the time of arrival measurements.
44. The method of claim 43 wherein the plural wireless nodes comprise plural base stations and a repeater and wherein transmitting one of the at least one base pilot signals from one of the plural nodes to at least one other of the plural nodes comprises transmitting a base pilot signal from one of the plural base stations to the repeater.
45. The method of claim 44 wherein determining location of the mobile unit includes ignoring the time of arrival measurement corresponding to the base pilot signal from the one of the plural base stations and considering time of arrival measurements corresponding to the auxiliary pilot signal from the repeater and the base pilot signals from the other of the plural base stations.
46. The method of claim 43 wherein the plural wireless nodes comprise a base station and plural radio access nodes and wherein transmitting one of the at least one base pilot signals from one of the plural nodes to at least one other of the plural nodes comprises transmitting a base pilot signal from the base station to the plural radio access nodes.
47. The method of claim 46 wherein determining location of the mobile unit includes considering time of arrival measurements corresponding to the auxiliary pilot signals from the plural radio access nodes and ignoring the time of arrival measurements corresponding to the base pilot signals.
48. The method of claim 43 wherein measuring time of arrival is based on any of enhanced observed time difference (E-OTD), advanced forward link trilateration (AFLT), and observed time difference of arrival (OTDOA) techniques.
49. The method of claim 43 wherein determining includes determining location from information defining locations of the nodes.
50. A method of determining location of a mobile unit in a wireless communication system, the method comprising:
transmitting a common base pilot signal from a base station to plural radio access nodes;
transmitting auxiliary pilot signals and the common base pilot signal from the radio access nodes, each auxiliary pilot signal having differing signaling parameters;
at a mobile unit, receiving the pilot signals and measuring time of arrival of the received pilot signals to provide time of arrival measurements;
and determining a location of the mobile unit from the time of arrival measurements.
51. The method of claim 50 wherein determining location of the mobile unit includes considering time of arrival measurements corresponding to the auxiliary pilot signals and ignoring the time of arrival measurement corresponding to the common base pilot signal.
52. The method of claim 50 wherein measuring time of arrival is based on any of enhanced observed time difference (E-OTD), advanced forward link trilateration (AFLT), and observed time difference of arrival (OTDOA) techniques.
CA002474140A 2002-01-29 2003-01-28 Method and apparatus for auxiliary pilot signal for mobile phone location Abandoned CA2474140A1 (en)

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US35261702P 2002-01-29 2002-01-29
US60/352,617 2002-01-29
PCT/US2003/002665 WO2003065757A1 (en) 2002-01-29 2003-01-28 Method and apparatus for auxiliary pilot signal for mobile phone location

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Families Citing this family (63)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU2001247819A1 (en) 2000-03-27 2001-10-08 Transcept Opencell, Inc. Multi-protocol distributed wireless system architecture
US7313626B2 (en) * 2000-03-29 2007-12-25 Adc Wireless Solutions Llc Operations and maintenace architecture for multiprotocol distributed system
US6704545B1 (en) 2000-07-19 2004-03-09 Adc Telecommunications, Inc. Point-to-multipoint digital radio frequency transport
US7039418B2 (en) * 2000-11-16 2006-05-02 Qualcomm Incorporated Position determination in a wireless communication system with detection and compensation for repeaters
US7027485B2 (en) * 2001-02-21 2006-04-11 Koninklijke Philips Electronics N.V. Signal discriminator for a spread spectrum system
US20040198451A1 (en) * 2002-06-11 2004-10-07 Andrew Corporation Tower top antenna structure with fiber optic communications link
CN1266976C (en) * 2002-10-15 2006-07-26 华为技术有限公司 Mobile station positioning method and its direct broadcasting station
US8958789B2 (en) 2002-12-03 2015-02-17 Adc Telecommunications, Inc. Distributed digital antenna system
US6909761B2 (en) * 2002-12-19 2005-06-21 Motorola, Inc. Digital communication system having improved pilot encoding
US7443805B1 (en) * 2003-02-05 2008-10-28 Sprint Spectrum L.P. Method and system for adjusting the configuration of devices in a wireless communication system
US8971913B2 (en) 2003-06-27 2015-03-03 Qualcomm Incorporated Method and apparatus for wireless network hybrid positioning
US8483717B2 (en) * 2003-06-27 2013-07-09 Qualcomm Incorporated Local area network assisted positioning
WO2005029897A1 (en) * 2003-09-19 2005-03-31 Bell Mobility Inc. Mobile user position locating system
US7570615B2 (en) 2003-10-20 2009-08-04 Telefonaktiebolaget Lm Ericsson (Publ) Resource-sharing cells
SE527308C2 (en) * 2003-10-20 2006-02-07 Ericsson Telefon Ab L M Apparatus and method for distributing resources between cells in a mobile communication network
US7319878B2 (en) 2004-06-18 2008-01-15 Qualcomm Incorporated Method and apparatus for determining location of a base station using a plurality of mobile stations in a wireless mobile network
US7257413B2 (en) * 2005-08-24 2007-08-14 Qualcomm Incorporated Dynamic location almanac for wireless base stations
US7751778B1 (en) * 2005-08-30 2010-07-06 Sprint Spectrum L.P. Method and system for increasing data transmission rates
RU2390791C2 (en) * 2005-11-07 2010-05-27 Квэлкомм Инкорпорейтед Positioning for wlan and other wireless networks
US7634250B1 (en) * 2006-03-17 2009-12-15 Sprint Spectrum L.P. Signal conditioner and method for communicating over a shared transport medium a combined digital signal for wireless service
US8670802B2 (en) * 2006-04-05 2014-03-11 Danko Antolovic Wireless network radiolocation apparatuses, systems and methods
KR100738920B1 (en) 2006-04-19 2007-07-12 에스케이 텔레콤주식회사 Method and system for detecting position of mobile communication terminal by using pilot strength measurement message
US20080085727A1 (en) * 2006-06-14 2008-04-10 Kratz Tyler M System and method for determining mobile device position information
GB2449278B (en) * 2007-05-16 2009-10-07 Multitone Electronics Plc Telecommunications system and method
CA2657573C (en) * 2006-07-14 2015-01-27 Multitone Electronics Plc Telecommunications system and method
US9226257B2 (en) * 2006-11-04 2015-12-29 Qualcomm Incorporated Positioning for WLANs and other wireless networks
US20100054746A1 (en) 2007-07-24 2010-03-04 Eric Raymond Logan Multi-port accumulator for radio-over-fiber (RoF) wireless picocellular systems
US8050291B1 (en) 2007-08-14 2011-11-01 Sprint Spectrum L.P. System and method for indoor wireless service distribution via ultra-wideband signals, and aggregation of combined digital signals for wireless service
US7848731B1 (en) 2007-08-14 2010-12-07 Sprint Spectrum L.P. System and method for communicating a combined digital signal for wireless service via integrated hybrid fiber coax and power line communication devices for a distributed antenna system over shared broadband media
US8175459B2 (en) 2007-10-12 2012-05-08 Corning Cable Systems Llc Hybrid wireless/wired RoF transponder and hybrid RoF communication system using same
EP2055962B1 (en) 2007-11-05 2017-12-06 Sulzer Management AG Centrifugal pump, a shaft sleeve and a stationary seal member
WO2009081376A2 (en) 2007-12-20 2009-07-02 Mobileaccess Networks Ltd. Extending outdoor location based services and applications into enclosed areas
CN101940044B (en) * 2008-01-29 2014-10-15 诺基亚公司 System and method for burst separation and extended interleaving length
KR100968927B1 (en) 2008-10-10 2010-07-14 알트론 주식회사 Method and apparatus for tracking location of mobile station
USRE47466E1 (en) 2009-01-13 2019-06-25 Commscope Technologies Llc Systems and methods for IP communication over a distributed antenna system transport
US8213401B2 (en) 2009-01-13 2012-07-03 Adc Telecommunications, Inc. Systems and methods for IP communication over a distributed antenna system transport
US8346278B2 (en) * 2009-01-13 2013-01-01 Adc Telecommunications, Inc. Systems and methods for mobile phone location with digital distributed antenna systems
US9793982B2 (en) 2009-04-21 2017-10-17 Commscope Technologies Llc System for automatic configuration of a mobile communication system
US8849190B2 (en) 2009-04-21 2014-09-30 Andrew Llc Radio communication systems with integrated location-based measurements for diagnostics and performance optimization
CN101873690A (en) * 2009-04-22 2010-10-27 北京三星通信技术研究有限公司 Method, system and device for locating mobile terminal
US9590733B2 (en) 2009-07-24 2017-03-07 Corning Optical Communications LLC Location tracking using fiber optic array cables and related systems and methods
US20110177827A1 (en) * 2010-01-19 2011-07-21 Cellular Specialties, Inc. Pilot Beacon System
CN102845001B (en) 2010-03-31 2016-07-06 康宁光缆系统有限责任公司 Based on positioning service in the distributed communication assembly of optical fiber and system and associated method
US8472579B2 (en) 2010-07-28 2013-06-25 Adc Telecommunications, Inc. Distributed digital reference clock
US8570914B2 (en) 2010-08-09 2013-10-29 Corning Cable Systems Llc Apparatuses, systems, and methods for determining location of a mobile device(s) in a distributed antenna system(s)
US8532242B2 (en) * 2010-10-27 2013-09-10 Adc Telecommunications, Inc. Distributed antenna system with combination of both all digital transport and hybrid digital/analog transport
US8731461B2 (en) 2010-11-22 2014-05-20 Cellular Specialties, Inc. Repeater for MIMO signals in a network
JP2014511646A (en) * 2011-03-07 2014-05-15 インテル コーポレイション Grouped inter-machine communication
EP2702710A4 (en) 2011-04-29 2014-10-29 Corning Cable Sys Llc Determining propagation delay of communications in distributed antenna systems, and related components, systems and methods
US8687540B2 (en) 2011-06-07 2014-04-01 Qualcomm Incorporated Echo cancellation repeater using an inserted pilot with gain-based power level control scheme
CA2790465A1 (en) 2011-10-03 2013-04-03 Cellular Specialties, Inc. Pilot beacon system for indoor positioning
US9781553B2 (en) 2012-04-24 2017-10-03 Corning Optical Communications LLC Location based services in a distributed communication system, and related components and methods
WO2013181247A1 (en) 2012-05-29 2013-12-05 Corning Cable Systems Llc Ultrasound-based localization of client devices with inertial navigation supplement in distributed communication systems and related devices and methods
US9158864B2 (en) 2012-12-21 2015-10-13 Corning Optical Communications Wireless Ltd Systems, methods, and devices for documenting a location of installed equipment
US9077321B2 (en) 2013-10-23 2015-07-07 Corning Optical Communications Wireless Ltd. Variable amplitude signal generators for generating a sinusoidal signal having limited direct current (DC) offset variation, and related devices, systems, and methods
EP3010271A1 (en) * 2014-10-13 2016-04-20 Vodafone IP Licensing limited Telecommunication system
WO2015197102A1 (en) * 2014-06-23 2015-12-30 Telecom Italia S.P.A. Fronthaul load dynamic reduction in centralized radio access networks
EP2978258B1 (en) * 2014-07-22 2017-03-08 Alcatel Lucent Seamless replacement of a first drone base station with a second drone base station
EP3010276A1 (en) * 2014-10-13 2016-04-20 Vodafone IP Licensing limited Configuration of communication devices
WO2016059064A1 (en) 2014-10-13 2016-04-21 Vodafone Ip Licensing Limited Telecommunication system for relaying cellular coverage
US10499269B2 (en) 2015-11-12 2019-12-03 Commscope Technologies Llc Systems and methods for assigning controlled nodes to channel interfaces of a controller
US9648580B1 (en) 2016-03-23 2017-05-09 Corning Optical Communications Wireless Ltd Identifying remote units in a wireless distribution system (WDS) based on assigned unique temporal delay patterns
US10897686B2 (en) * 2016-03-24 2021-01-19 Qualcomm Incorporated Determining a time calibration value for a user equipment

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5263177A (en) * 1991-01-22 1993-11-16 Motorola, Inc. Modified simulcast communication system
AU7173694A (en) * 1993-06-25 1995-01-17 Omniplex, Inc. Determination of location using time-synchronized cell site transmissions
US5508708A (en) * 1995-05-08 1996-04-16 Motorola, Inc. Method and apparatus for location finding in a CDMA system
US5987326A (en) * 1997-02-11 1999-11-16 Qualcomm Incorporated Transmit power reduction for a high speed CDMA link in soft handoff
US5970414A (en) * 1997-05-30 1999-10-19 Lucent Technologies, Inc. Method for estimating a mobile-telephone's location
US6195342B1 (en) * 1997-11-25 2001-02-27 Motorola, Inc. Method for determining hand-off candidates in a neighbor set in a CDMA communication system
KR100326330B1 (en) * 1998-05-08 2002-06-26 윤종용 Hand-off apparatus for mobile communication system and method therefor
US5969679A (en) * 1998-06-30 1999-10-19 Lucent Technologies Inc. Method and apparatus for determining whether a wireless station is operating within a prescribed geographic region
AU2001247819A1 (en) * 2000-03-27 2001-10-08 Transcept Opencell, Inc. Multi-protocol distributed wireless system architecture
FI109839B (en) * 2000-08-22 2002-10-15 Nokia Corp A method for locating a mobile station
EP1202475B1 (en) * 2000-10-25 2007-04-11 NTT DoCoMo, Inc. Communication system having radio units connected to optical fibers
US7039418B2 (en) * 2000-11-16 2006-05-02 Qualcomm Incorporated Position determination in a wireless communication system with detection and compensation for repeaters
US20030008663A1 (en) * 2001-04-24 2003-01-09 Stein Jeremy M. Method and apparatus for estimating the postion of a terminal based on identification codes for transmission sources
CN101600250B (en) * 2001-04-24 2011-07-27 高通股份有限公司 Method and apparatus for estimating the position of a terminal based on identification codes for transmission sources
US6889056B2 (en) * 2001-04-30 2005-05-03 Ntt Docomo, Inc. Transmission control scheme
US20030050041A1 (en) * 2001-09-07 2003-03-13 Robert Wu Network system for providing prepaid wireless remote access service

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