CN103323835A - Antenna range direction weighting specific value height measurement method and device - Google Patents

Abstract

The invention discloses an antenna range direction weighting specific value height measurement method. The method includes the steps of acquiring two images in the same scene in a time-sharing mode by using a phased array single antenna, determining the pixel ratio of the two images as the ratio of range direction weighting functions of time-sharing antennae, determining a target viewing angle according to the ratio of the range direction weighting functions, and determining a target height according to the target viewing angle. The invention further discloses an antenna range direction weighting specific value height measurement device. With the antenna range direction weighting specific value height measurement method and device, the height of a target object can be measured with small calculated amount, height measurement accuracy is guaranteed, and conflict between height measurement accuracy and registration accuracy and conflict between phase ambiguity and height measurement accuracy are avoided.

Description

A kind of antenna distance is surveyed high method and device to weighting ratio

Technical field

The present invention relates to synthetic-aperture radar (SAR, Synthetic Aperture Radar) height-finding technique, relate in particular to a kind of antenna distance and survey high method and device to weighting ratio.

Background technology

The height-finding technique that generally adopts comprises single track interference synthetic aperture radar technology and rerail interference synthetic aperture radar technology at present.Wherein, utilize single track interference synthetic aperture radar technology to survey when high, time decorrelation influence is little, altimetry precision is high but SAR system cost costliness; Utilize rerail interference synthetic aperture radar technology to survey when high, altimetry precision is subjected to the influence of baseline decorrelation big.In addition, these two kinds traditional interference synthetic aperture radar technology exist total shortcoming: the one, survey that high algorithm steps is many, algorithm is complicated; The 2nd, mainly use phase place to finish the measurement of higher degree, the factor that influences altimetry precision is many, and wherein altimetry precision and registration accuracy, phase ambiguity and altimetry precision are two pairs of contradictions can't going beyond.

But, above-mentioned two pairs of contradictions all can be aggravated along with the raising of SAR resolution and measurement of higher degree requirement, and the existence of registration accuracy problem causes owing to interfering both sides' antenna flight path not overlap, and is that traditional interference technique itself requires and interfere both sides' antenna flight path not overlap; Phase ambiguity then is to utilize phase place to carry out the common problem of correlation parameter inverting.Therefore, seek new SAR height measurement method and be a kind of inevitable, study that a kind of simply, effectively to survey high method be to need the problem of solution at present badly.

Summary of the invention

In view of this, fundamental purpose of the present invention is to provide a kind of antenna distance to survey high method and device to weighting ratio, can realize measurement to the height of object with lower calculated amount, the problem of having avoided altimetry precision and registration accuracy, phase ambiguity to conflict with altimetry precision.

For achieving the above object, technical scheme of the present invention is achieved in that

A kind of antenna distance is surveyed high method to weighting ratio, comprising:

Utilize the timesharing of phased array single antenna to obtain two width of cloth images of Same Scene;

Determine the pixel ratio of described two width of cloth images, as the distance of the timesharing antenna ratio to weighting function;

Utilize described distance to determine the target visual angle to the ratio of weighting function, determine object height according to described target visual angle.

Preferably, described two width of cloth images that utilize the timesharing of phased array single antenna to obtain Same Scene comprise:

The designing antenna directional diagram obtains two slave antennas by the single antenna time-sharing format; Wherein, described two slave antennas make distance in the antenna parameter to the weighting function difference, and all the other parameters are all identical; Described all the other parameters comprise that at least emissive power, orientation are to gain, target backscattering cross coefficient, operating distance, imaging factor of influence.

Preferably, the described pixel ratio of determining described two width of cloth images comprises:

Determine the ratio of pixel value corresponding in two width of cloth images respectively by pixel, with the mathematical mean of the ratio of pixel value or the weighted mean value pixel ratio as described two width of cloth images.

Preferably, the described pixel ratio of determining described two width of cloth images as the distance of the timesharing antenna ratio to weighting function, comprising:

The corresponding pixel of described two width of cloth images is respectively P _S1, P _S2The time,

$P_{s1}=K\frac{P_t{G}_a{G}_1\left(\mathrm{\θ}\right){\mathrm{\λ}}^2}{{\left(4\mathrm{\π}\right)}^3{R}^4}\mathrm{\σ}+N_1$

${\mathrm{<figure-callout\; id="2"\; label="P\; s"\; filenames="HDA00002905713500032.png"\; state="\{\{state\}\}">P</figure-callout>}}_s=K\frac{P_t{G}_a{G}_2\left(\mathrm{\&theta;}\right){\mathrm{\&lambda;}}^2}{{\left(4\mathrm{\&pi;}\right)}^3{R}^4}\mathrm{\&sigma;}+{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="HDA00002905713500032.png"\; state="\{\{state\}\}">N</figure-callout>}}_2$

Wherein, P _tBe the emissive power of phased array single antenna, G _aFor the orientation to gain, G ₁(θ), G ₂(θ) distance that is respectively antenna is to gain function, and λ is signal wavelength, and σ is target backscattering cross coefficient, and R is operating distance, N ₁, N ₂Be respectively noise after the imaging, K is the imaging factor of influence;

And N ₁, N ₂Enough little, then

$\frac{P_{s1}}{{\mathrm{<figure-callout\; id="2"\; label="P\; s"\; filenames="HDA00002905713500032.png"\; state="\{\{state\}\}">P</figure-callout>}}_s}=\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}.$

Preferably, utilize antenna distance to determine the target visual angle to the ratio of weighting function, comprising:

Antenna distance to the ratio of the weighting function function of negating, is determined the target visual angle;

Describedly utilize described distance to determine the target visual angle to the ratio of weighting function, determine object height according to described target visual angle, comprising:

Order To G (θ) function of negating, obtain the target view angle theta and be:

$\mathrm{\&theta;}\&ap;G^{-1}\left(\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}\right)$

Wherein, G ^-1(θ) be the inverse function of G (θ), the span of θ is 0≤θ＜pi/2;

Determine object height h by following formula:

$h=r\&times;\cos \left(G^{-1}\left(\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}\right)\right)$

Wherein, r is oblique distance.

Preferably, this method also comprises:

Make the measurement merged of described two slave antennas.

A kind of antenna distance is to weighting ratio height measuring device, and this device comprises: image collection module, the distance to weighting function than determination module and object height determination module; Wherein,

Described image collection module is used for utilizing the timesharing of phased array single antenna to obtain two width of cloth images of Same Scene;

Described distance than determination module, be used for to be determined the pixel ratio of described two width of cloth images to weighting function, as the distance of the timesharing antenna ratio to weighting function;

Described object height determination module is used for utilizing the distance of antenna to determine the target visual angle to the ratio of weighting function, determines object height according to described target visual angle.

Preferably, described image collection module also is used for the designing antenna directional diagram, obtains two slave antennas by the single antenna time-sharing format; Wherein, described two slave antennas make distance in the antenna parameter to the weighting function difference, and all the other parameters are all identical; Described all the other parameters comprise that emissive power, orientation are to gain, target backscattering cross coefficient, operating distance, imaging factor of influence.

Preferably, described distance than determination module, also is used for determining respectively by pixel the ratio of the pixel value that two width of cloth images are corresponding to weighting function, with the mathematical mean of the ratio of pixel value or the weighted mean value pixel ratio as described two width of cloth images.

Preferably, described distance is determined the pixel ratio of described two width of cloth images to weighting function than determination module, as the distance of the timesharing antenna ratio to weighting function, comprising:

The corresponding pixel of described two width of cloth images is respectively P _S1, P _S2The time,

$P_{s1}=K\frac{P_t{G}_a{G}_1\left(\mathrm{\&theta;}\right){\mathrm{\&lambda;}}^2}{{\left(4\mathrm{\&pi;}\right)}^3{R}^4}\mathrm{\&sigma;}+N_1$

${\mathrm{<figure-callout\; id="2"\; label="P\; s"\; filenames="HDA00002905713500032.png"\; state="\{\{state\}\}">P</figure-callout>}}_s=K\frac{P_t{G}_a{G}_2\left(\mathrm{\&theta;}\right){\mathrm{\&lambda;}}^2}{{\left(4\mathrm{\&pi;}\right)}^3{R}^4}\mathrm{\&sigma;}+{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="HDA00002905713500032.png"\; state="\{\{state\}\}">N</figure-callout>}}_2$

Wherein, P _tBe the emissive power of phased array single antenna, G _aFor the orientation to gain, G ₁(θ), G ₂(θ) distance that is respectively antenna is to gain function, and λ is signal wavelength, and σ is target backscattering cross coefficient, and R is operating distance, N ₁, N ₂Be respectively noise after the imaging, K is the imaging factor of influence;

And N ₁, N ₂Enough little, then

$\frac{P_{s1}}{{\mathrm{<figure-callout\; id="2"\; label="P\; s"\; filenames="HDA00002905713500032.png"\; state="\{\{state\}\}">P</figure-callout>}}_s}=\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}.$

Preferably, described object height determination module also is used for antenna distance determining the target visual angle to the ratio of the weighting function function of negating;

Described object height determination module utilizes described distance to determine the target visual angle to the ratio of weighting function, determines object height according to described target visual angle, comprising:

Order

To G (θ) function of negating, obtain the target view angle theta and be:

$\mathrm{\&theta;}\&ap;G^{-1}\left(\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}\right)$

Wherein, G ^-1(θ) be the inverse function of G (θ), the span of θ is 0≤θ＜pi/2;

Determine object height h by following formula:

$h=r\&times;\cos \left(G^{-1}\left(\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}\right)\right)$

Wherein, r is oblique distance.

Antenna distance provided by the invention is surveyed high method and device to weighting ratio, utilizes the timesharing of phased array single antenna to obtain two width of cloth images of Same Scene; Determine the pixel ratio of described two width of cloth images, as the distance of the timesharing antenna ratio to weighting function; Utilize described distance to determine the target visual angle to the ratio of weighting function, determine object height according to described target visual angle.So, the present invention can realize the measurement of the height of object has been guaranteed altimetry precision with lower calculated amount; The problem of having avoided altimetry precision and registration accuracy, phase ambiguity to conflict with altimetry precision.And method provided by the invention is simple, can also carry out accurate inverting to landform.

Description of drawings

Fig. 1 surveys the realization flow synoptic diagram of high method to weighted ratio for antenna distance of the present invention;

Fig. 2 is the directional diagram of two slave antennas;

Fig. 3 is the composition structural representation of antenna distance of the present invention to the weighted ratio height measuring device;

Fig. 4 is the optical imagery of embodiment of the invention measured data;

Fig. 5 is the radar image of embodiment of the invention measured data;

Fig. 6 is the landform inversion chart of embodiment of the invention measured data.

Embodiment

The technical solution of the present invention is further elaborated below in conjunction with the drawings and specific embodiments.

Fig. 1 surveys the realization flow synoptic diagram of high method for antenna distance of the present invention to weighted ratio, and as shown in Figure 1, described method comprises:

Step 101: utilize the timesharing of phased array single antenna to obtain two width of cloth images of Same Scene;

Concrete, described two width of cloth images that utilize the timesharing of phased array single antenna to obtain Same Scene comprise:

The designing antenna directional diagram obtains two slave antennas by the single antenna time-sharing format;

Wherein, described two slave antennas make distance in the antenna parameter to the weighting function difference, and all the other parameters are all identical; Described all the other parameters comprise that at least emissive power, orientation are to gain, target backscattering cross coefficient, operating distance, imaging factor of influence.

Here, this step utilizes existing phased array single antenna time sharing to obtain two width of cloth radar images of Same Scene, so that the follow-up antenna distance that obtains is to weighted ratio, and then definite target view angle theta.

Concrete, utilize phased array single antenna time sharing designing antenna directional diagram, obtain two slave antennas by the single antenna time-sharing format, so that two width of cloth image pixels are than being the monotonic quantity at target visual angle.

Here, the method for designing antenna directional diagram is same as the prior art, does not repeat them here; Such as, antenna radiation pattern can be designed to the directional diagram of two slave antennas as shown in Figure 2.

Step 102: determine the pixel ratio of described two width of cloth images, as the distance of the timesharing antenna ratio to weighting function;

Concrete, described distance weighted function is than unique with the corresponding relation at target visual angle;

Concrete, the pixel ratio of described two width of cloth images also is the strength ratio of two width of cloth images.

Concrete, the described pixel ratio of determining described two width of cloth images comprises:

Determine the ratio of pixel value corresponding in two width of cloth images respectively by pixel, with the mathematical mean of the ratio of pixel value or the weighted mean value pixel ratio as described two width of cloth images.

Here, the described pixel ratio of determining described two width of cloth images as the distance of the timesharing antenna ratio to weighting function, comprising:

The corresponding pixel of described two width of cloth images is respectively P _S1, P _S2The time,

$P_{s1}=K\frac{P_t{G}_a{G}_1\left(\mathrm{\&theta;}\right){\mathrm{\&lambda;}}^2}{{\left(4\mathrm{\&pi;}\right)}^3{R}^4}\mathrm{\&sigma;}+N_1---\left(1\right)$

$P_{s2}=K\frac{P_t{G}_a{G}_2\left(\mathrm{\&theta;}\right){\mathrm{\&lambda;}}^2}{{\left(4\mathrm{\&pi;}\right)}^3{R}^4}\mathrm{\&sigma;}+N_2---\left(2\right)$

Wherein, the emissive power of phased array single antenna is P _t, the orientation is G to gain _a, the distance of antenna is respectively G to gain function ₁(θ), G ₂(θ), signal wavelength is λ, and target backscattering cross coefficient is σ, and operating distance is R, and noise is respectively N after the imaging ₁, N ₂, the imaging factor of influence is K.

Be N when making the enough height of signal to noise ratio (S/N ratio) ₁, N ₂Enough hour, then have:

$\frac{P_{s1}}{P_{s2}}=\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}---\left(3\right)$

Here, can obtain the distance of antenna to the ratio of weighting function by step 102.

Step 103: utilize the distance of antenna to determine the target visual angle to the ratio of weighting function, determine object height according to described target visual angle.

Concrete, described utilizations distance to the ratio of weighting function determine the target visual angle be to antenna distance to the ratio of the weighting function function of negating, determine the target visual angle;

Concrete, describedly utilize described distance to determine the target visual angle to the ratio of weighting function, determine object height according to described target visual angle, comprising:

Make target weighting function ratio

To G (θ) function of negating, obtain the target view angle theta and be:

$\mathrm{\&theta;}\&ap;G^{-1}\left(\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}\right)---\left(4\right)$

Wherein, G ^-1(θ) be the inverse function of G (θ), the span of θ is 0≤θ＜pi/2;

Determine object height h by following formula:

$h=r\&times;\cos \left(G^{-1}\left(\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}\right)\right)---\left(5\right)$

Wherein, r is oblique distance.

Here, after step 103 is finished, namely finished target and surveyed high.

The present invention utilizes phased array single antenna time sharing designing antenna directional diagram, obtains two slave antennas by the single antenna time-sharing format; Wherein, described two slave antennas make distance in the antenna parameter to the weighting function difference, and all the other parameters are all measured merged during identical and flight, described utilize two width of cloth images that the timesharing of phased array single antenna obtains Same Scene after, the corresponding pixel of its two width of cloth image is similar to two antenna distances of target visual angle correspondence to the ratio of weighting function than in fact; As long as distance is unique with the corresponding relation at target visual angle to the ratio of weighting function, the target visual angle just can be recently definite by the pixel of two width of cloth images, and then can determine object height.

Because the antenna flight path overlaps fully, therefore there is not the image registration problem to weighting ratio altimetry in antenna distance of the present invention; And directly by image pixel ratio reckoning target visual angle, do not have phase fuzzy problem yet; Can prove determine antenna distance to weighting ratio altimetry precision mainly be target signal to noise ratio, in theory as long as signal to noise ratio (S/N ratio) is enough high, any precision all can reach and not have a problem that conditions each other; Surveying another high problem is the measurement range problem, different with traditional altimetry, antenna distance of the present invention only is subjected to the restriction of operating distance and target angular field of view to the high scope of the survey of weighted ratio altimetry, such as: to the operating distance of 10km, if the target angular field of view is 30～80 (degree), then its elevation scope can reach 7Km.

Fig. 3 for antenna distance of the present invention to the composition structural representation of weighted ratio height measuring device, as shown in Figure 3, this device comprises: image collection module 31, distance to weighting function than determination module 32 and object height determination module 33; Wherein,

Described image collection module 31 is used for utilizing the timesharing of phased array single antenna to obtain two width of cloth images of Same Scene;

Described distance than determination module 32, be used for to be determined the pixel ratio of described two width of cloth images to weighting function, as the distance of the timesharing antenna ratio to weighting function;

Described object height determination module 33 is used for utilizing the distance of antenna to determine the target visual angle to the ratio of weighting function, determines object height according to described target visual angle.

Concrete, described image collection module 31 also is used for the designing antenna directional diagram, obtains two slave antennas by the single antenna time-sharing format; Wherein, described two slave antennas make distance in the antenna parameter to the weighting function difference, and all the other parameters are all identical; Described all the other parameters comprise that at least emissive power, orientation are to gain, target backscattering cross coefficient, operating distance, imaging factor of influence.

Concrete, described distance than determination module 32, also is used for determining respectively by pixel the ratio of the pixel value that two width of cloth images are corresponding to weighting function, with the mathematical mean of the ratio of pixel value or the weighted mean value pixel ratio as described two width of cloth images.

Concrete, described object height determination module 33 also is used for, and antenna distance to the ratio of the weighting function function of negating, is determined the target visual angle.

Concrete, the measurement merged of two slave antennas that described image collection module is obtained.

Concrete, the function of described image collection module 31 can realize by the processing mode of step 101 record; Described distance can realize by the processing mode of abovementioned steps 102 records to the function of weighting function than determination module 32, does not repeat them here.Described object height determination module 33 can calculate the target visual angle by the mode of formula (4) record, and then calculates object height according to formula (5).

The realization function that it will be appreciated by those skilled in the art that each processing module of the antenna distance shown in Fig. 3 in the weighted ratio height measuring device can be surveyed the associated description of high method and understands to weighted ratio with reference to aforementioned antenna distance.It will be appreciated by those skilled in the art that the antenna distance shown in Figure 3 function of each processing unit in the weighted ratio height measuring device can realize by the program that runs on the processor, also can realize by concrete logical circuit.

In order to illustrate that better the present invention surveys the realization effect of high method, the high method of survey of the present invention can be applied to that miniature (mini miniature) in the SAR system, experimentizes.For example: the experiment place is at the wild goose West Lake, Huairou District, Beijing City reservoir dam periphery, as shown in Figure 4, the optical imagery of Fig. 4 for obtaining by Google Maps (google earth), what the rectangular area among Fig. 4 marked is the imaging place, dam is high about 20 meters in the image, and all the other areas are for can be considered acclive uneven surface.The radar parameter of described miniSAR system is listed in table 1.

Table 1

Parameter name	Parameter value
		Wavelength (m)	0.03125
View angle (°)	55
		Resolution (m)	0.3
The orientation is to beam angle (rad)	0.15

Two width of cloth radar images that the miniSAR system obtains are respectively shown in Fig. 5 (a) and 5 (b); Utilize Terrain Elevation that the present invention surveys high method inverting as shown in Figure 6.As seen from Figure 6, the Terrain Elevation of inverting conforms to the actual conditions that optical image shows substantially, and the dam height probably is 20 meters, and the hillside fields transition is 0 meter.

Experimental result shows that the high method of survey that the present invention proposes is particularly suitable for the measurement of Terrain Elevation.

The above is preferred embodiment of the present invention only, is not for limiting protection scope of the present invention.

Claims (11)

1. an antenna distance is surveyed high method to weighting ratio, it is characterized in that, this method comprises:

Utilize the timesharing of phased array single antenna to obtain two width of cloth images of Same Scene;

Determine the pixel ratio of described two width of cloth images, as the distance of the timesharing antenna ratio to weighting function;

Utilize described distance to determine the target visual angle to the ratio of weighting function, determine object height according to described target visual angle.

2. method according to claim 1 is characterized in that, described two width of cloth images that utilize the timesharing of phased array single antenna to obtain Same Scene comprise:

The designing antenna directional diagram obtains two slave antennas by the single antenna time-sharing format; Wherein, described two slave antennas make distance in the antenna parameter to the weighting function difference, and all the other parameters are all identical; Described all the other parameters comprise that at least emissive power, orientation are to gain, target backscattering cross coefficient, operating distance, imaging factor of influence.

3. method according to claim 1 is characterized in that, the described pixel ratio of determining described two width of cloth images comprises:

Determine the ratio of pixel value corresponding in two width of cloth images respectively by pixel, with the mathematical mean of the ratio of pixel value or the weighted mean value pixel ratio as described two width of cloth images.

4. method according to claim 1 is characterized in that, the described pixel ratio of determining described two width of cloth images as the distance of the timesharing antenna ratio to weighting function, comprising:

The corresponding pixel of described two width of cloth images is respectively P _S1, P _S2The time,

$P_{s1}=K\frac{P_t{G}_a{G}_1\left(\mathrm{\&theta;}\right){\mathrm{\&lambda;}}^2}{{\left(4\mathrm{\&pi;}\right)}^3{R}^4}\mathrm{\&sigma;}+N_1$

$P_{s2}=K\frac{P_t{G}_a{G}_2\left(\mathrm{\&theta;}\right){\mathrm{\&lambda;}}^2}{{\left(4\mathrm{\&pi;}\right)}^3{R}^4}\mathrm{\&sigma;}+N_2$

Wherein, P _tBe the emissive power of phased array single antenna, G _aFor the orientation to gain, G ₁(θ), G ₂(θ) distance that is respectively antenna is to gain function, and λ is signal wavelength, and σ is target backscattering cross coefficient, and R is operating distance, N ₁, N ₂Be respectively noise after the imaging, K is the imaging factor of influence;

And N ₁, N ₂Enough little, then

$\frac{P_{s1}}{P_{s2}}=\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}.$

5. method according to claim 1 is characterized in that, utilizes antenna distance to determine the target visual angle to the ratio of weighting function, comprising:

Antenna distance to the ratio of the weighting function function of negating, is determined the target visual angle;

Describedly utilize described distance to determine the target visual angle to the ratio of weighting function, determine object height according to described target visual angle, comprising:

Order

To G (θ) function of negating, obtain the target view angle theta and be:

$\mathrm{\&theta;}\&ap;G^{-1}\left(\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}\right)$

Wherein, G ^-1(θ) be the inverse function of G (θ), the span of θ is 0≤θ＜pi/2;

Determine object height h by following formula:

$h=r\&times;\cos \left(G^{-1}\left(\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}\right)\right)$

Wherein, r is oblique distance.

6. method according to claim 2 is characterized in that, this method also comprises:

Make the measurement merged of described two slave antennas.

7. an antenna distance is characterized in that to weighting ratio height measuring device this device comprises: image collection module, the distance to weighting function than determination module and object height determination module; Wherein,

Described image collection module is used for utilizing the timesharing of phased array single antenna to obtain two width of cloth images of Same Scene;

Described distance than determination module, be used for to be determined the pixel ratio of described two width of cloth images to weighting function, as the distance of the timesharing antenna ratio to weighting function;

Described object height determination module is used for utilizing the distance of antenna to determine the target visual angle to the ratio of weighting function, determines object height according to described target visual angle.

8. device according to claim 7 is characterized in that, described image collection module also is used for the designing antenna directional diagram, obtains two slave antennas by the single antenna time-sharing format; Wherein, described two slave antennas make distance in the antenna parameter to the weighting function difference, and all the other parameters are all identical; Described all the other parameters comprise that at least emissive power, orientation are to gain, target backscattering cross coefficient, operating distance, imaging factor of influence.

9. device according to claim 7 is characterized in that,

Described distance than determination module, also is used for determining respectively by pixel the ratio of the pixel value that two width of cloth images are corresponding to weighting function, with the mathematical mean of the ratio of pixel value or the weighted mean value pixel ratio as described two width of cloth images.

10. device according to claim 7 is characterized in that, described distance is determined the pixel ratio of described two width of cloth images to weighting function than determination module, as the distance of the timesharing antenna ratio to weighting function, comprising:

The corresponding pixel of described two width of cloth images is respectively P _S1, P _sDuring x,

$P_{s1}=K\frac{P_t{G}_a{G}_1\left(\mathrm{\&theta;}\right){\mathrm{\&lambda;}}^2}{{\left(4\mathrm{\&pi;}\right)}^3{R}^4}\mathrm{\&sigma;}+N_1$

$P_{s2}=K\frac{P_t{G}_a{G}_2\left(\mathrm{\&theta;}\right){\mathrm{\&lambda;}}^2}{{\left(4\mathrm{\&pi;}\right)}^3{R}^4}\mathrm{\&sigma;}+N_2$

Wherein, P _tBe the emissive power of phased array single antenna, G _aFor the orientation to gain, G ₁(θ), G ₂(θ) distance that is respectively antenna is to gain function, and λ is signal wavelength, and σ is target backscattering cross coefficient, and R is operating distance, N ₁, N ₂Be respectively noise after the imaging, K is the imaging factor of influence;

And N ₁, N ₂Enough little, then

$\frac{P_{s1}}{P_{s2}}=\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}.$

11. device according to claim 7 is characterized in that,

Described object height determination module also is used for antenna distance determining the target visual angle to the ratio of the weighting function function of negating;

Described object height determination module utilizes described distance to determine the target visual angle to the ratio of weighting function, determines object height according to described target visual angle, comprising:

Order

To G (θ) function of negating, obtain the target view angle theta and be:

$\mathrm{\&theta;}\&ap;G^{-1}\left(\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}\right)$

Wherein, G ^-1(θ) be the inverse function of G (θ), the span of θ is 0≤θ＜pi/2;

Determine object height h by following formula:

$h=r\&times;\cos \left(G^{-1}\left(\frac{G_1\left(\mathrm{\&theta;}\right)}{G_2\left(\mathrm{\&theta;}\right)}\right)\right)$

Wherein, r is oblique distance.

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