A method for joint localization of radiation sources and scattering points

Abstract

The present application belongs to the field of radio positioning technology, and particularly relates to a radiation source and scattering point joint positioning. The method of the present application is to detect the radiation source through a primary station and an auxiliary station, and meanwhile, there is a scattering point in the detection area, the scattering point scatters the signal of the radiation source, the primary station and the auxiliary station receive the direct wave signal of the radiation source and also receive the scattering signal of the scattering point, and the joint positioning of the radiation source and the scattering point is realized. The method of the present application utilizes a primary station passive detection device and an auxiliary station primary station passive detection device to measure the direction of arrival and the time difference of arrival, and only by using the double stations, the joint positioning of the radiation source and the scattering point can be realized, which can be applied to the application scene that there is a radiation source with a radiation signal in the detection area and multiple scattering points scattering the radiation signal of the radiation source.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of radio positioning, and particularly relates to a radiation source and scattering point joint positioning. BACKGROUND

[0002] The method of using a main station passive detection device and an auxiliary station main station passive detection device to measure the direction of arrival of a radiation source signal and to cross locate by double station direction finding is a commonly used passive positioning method, and has been widely applied to the fields of radio monitoring, spectrum management and interference source positioning.

[0003] In actual application, the signals received by the main station passive detection device and the auxiliary station main station passive detection device not only include direct wave signals radiated by the radiation source, but also include signals scattered by scattering points reflecting the radiation signals radiated by the radiation source. Therefore, the double station direction finding cross location can not only locate the radiation source, but also can locate the scattering points in the environment. However, when the main station passive detection device and the auxiliary station main station passive detection device measure the direction of arrival, the direction of arrival of the direct wave signals radiated by the radiation source and the signals scattered by multiple scattering points can be determined, so that the cross location points obtained by the double station direction finding cross location are much more than the number of radiation sources and the number of scattering points, and it is difficult to locate the positions of the radiation sources and the scattering points from the numerous cross location points.

[0004] In order to locate the positions of the radiation sources and the scattering points from the numerous cross location points, a commonly used method is a multi-station direction finding cross location method with two or more auxiliary stations. In the cross location points determined by the cross location of the main station and the first auxiliary station, the cross location point closest to the straight line corresponding to the direction of arrival measurement determined by the second auxiliary station is selected as the position of the radiation source and the scattering point. However, the multi-station direction finding cross location method needs to increase the number of auxiliary stations, which increases the complexity and cost of the passive positioning system.

[0005] In fact, when the main station passive detection device and the auxiliary station main station passive detection device measure the direction of arrival, not only the direction of arrival of the direct wave signals radiated by the radiation source and the signals scattered by multiple scattering points can be determined, but also the time difference of arrival of the signals scattered by multiple scattering points relative to the direct wave signals radiated by the radiation source can be determined. Therefore, it is necessary to develop a positioning method using one main station passive detection device and one auxiliary station main station passive detection device to measure the direction of arrival and the time difference of arrival, so as to realize the joint positioning of the radiation source and the scattering point in the double station case. SUMMARY

[0006] In response to the above problems, the present invention proposes a method for jointly locating radiation sources and scattering points. For the case where there is a radiation source with a radiation signal and multiple scattering points that scatter the radiation signal of the radiation source in the detection area, first, the two-dimensional rectangular coordinates of the main station and the auxiliary station are set, the main station determines the direction of arrival of the direct wave signal radiated by the earliest arriving radiation source, the direction of arrival of the scattered signal of the scattering point that scatters the radiation signal of the radiation source, and the arrival time difference relative to the direct wave signal radiated by the radiation source, the auxiliary station determines the direction of arrival of the direct wave signal radiated by the earliest arriving radiation source, the direction of arrival of the scattered signal of the scattering point that scatters the radiation signal of the radiation source, and the arrival time difference relative to the direct wave signal radiated by the earliest arriving radiation source; secondly, the direction of arrival of the direct wave signal radiated by the earliest arriving radiation source determined by the main station and the direction of arrival of the direct wave signal radiated by the earliest arriving radiation source determined by the auxiliary station are used to determine the direction of arrival of the radiation source. The distance vector of the two stations of the radiation source is obtained; then, the pairing vector of the wave directions of the scattering signal of the scattering point determined by the main station and the wave direction of the scattering signal of the scattering point determined by the auxiliary station is determined, thereby determining the pairing matrix of the wave directions of the main station and the auxiliary station; then, the arrival time difference of the scattering signal of the scattering point determined by the main station relative to the direct wave signal radiated by the earliest arriving radiation source and the arrival time difference of the scattering signal of the scattering point determined by the auxiliary station relative to the direct wave signal radiated by the earliest arriving radiation source are used to determine the pairing matrix of the arrival time difference of the main station and the auxiliary station; then, the difference matrix of the pairing matrix of the wave direction and the pairing matrix of the arrival time difference and the element number with the smallest absolute value among all elements of each row vector thereof are determined, thereby determining the distance vector of the two stations of the scattering point; finally, the two-dimensional rectangular coordinate vector of the radiation source and the two-dimensional rectangular coordinate vector of the scattering point are determined, thereby determining the joint positioning result of the radiation source and the scattering point.

[0007] The technical solution of the present invention is:

[0008] A method for jointly locating a radiation source and a scattering point is disclosed. The method comprises detecting the radiation source through a primary station and a secondary station. N scattering points are provided in a detection area. The scattering points scatter signals from the radiation source. The primary station and the secondary station receive scattered signals from the scattering points while receiving direct wave signals from the radiation source, thereby achieving joint positioning of the radiation source and the scattering points. The method specifically comprises the following steps:

[0009] S1. Set the two-dimensional rectangular coordinate vectors of the two passive detection devices, the master station and the auxiliary station, to be p1 and p2 respectively. There is a radiation source and N scattering points that scatter the radiation signal of the radiation source in the detection area. The direction of the direct wave signal emitted by the radiation source that arrives earliest, determined by the master station, is θ. 1,0 The direction of the scattered signal from the scattering point determined by the master station to scatter the radiation signal of the radiation source is θ 1,n , the arrival time difference of the direct wave signal relative to the earliest arriving radiation source is τ1,n , n is the sequence number of the scattered signal direction and arrival time difference determined by the master station, which is an integer greater than or equal to 1 and less than or equal to N; the direct wave signal direction of the earliest arriving radiation source determined by the slave station is θ 2,0 The direction of the scattered signal from the scattering point determined by the auxiliary station to scatter the radiation signal of the radiation source is θ 2,k , the arrival time difference of the direct wave signal relative to the earliest arriving radiation source is τ 2,k , k is the serial number of the direction and arrival time difference of the scattered signal determined by the auxiliary station, which is an integer greater than or equal to 1 and less than or equal to N;

[0010] S2, the direction of the direct wave signal from the earliest arriving radiation source determined by the master station θ 1,0 The direction of the direct wave signal emitted by the earliest radiation source determined by the auxiliary station is θ 2,0 , determine the distance vector between the two stations of the radiation source as

[0011]

[0012] in,[] -1 represents the inverse matrix;

[0013] S3, using the scattered signal of the scattering point determined by the master station, the wave direction is θ 1,n The direction of the scattered signal from the scattering point determined by the auxiliary station is θ 2,k , determine the pairing vector of the incoming wave direction of the primary station and the secondary station as

[0014]

[0015] Thus, the pairing matrix Q1 of the incoming wave direction of the primary station and the secondary station is determined, and its n-th row and k-th column element Q1(n,k) is

[0016] Q1(n,k)=1 T (r n,k -r0);

[0017] Among them, 1 T represents a two-dimensional row vector whose elements are all equal to 1, n is the sequence number of the scattered signal arrival direction and arrival time difference determined by the primary station, which is an integer greater than or equal to 1 and less than or equal to N, and k is the sequence number of the scattered signal arrival direction and arrival time difference determined by the secondary station, which is an integer greater than or equal to 1 and less than or equal to N;

[0018] S4, using the arrival time difference τ of the scattered signal of the nth scattering point determined by the master station relative to the direct wave signal radiated by the earliest arriving radiation source 1,n , and the arrival time difference τ of the scattered signal of the kth scattering point determined by the auxiliary station relative to the direct wave signal radiated by the earliest arriving radiation source 2,k, determine the pairing matrix Q2 of the arrival time difference between the primary station and the secondary station, whose nth row and kth column element Q2(n,k) is

[0019] Q2(n,k)=c(τ 1,n -τ 2,k );

[0020] Where c is the speed of light, n is the sequence number of the scattered signal arrival direction and arrival time difference determined by the primary station, which is an integer greater than or equal to 1 and less than or equal to N, and k is the sequence number of the scattered signal arrival direction and arrival time difference determined by the secondary station, which is an integer greater than or equal to 1 and less than or equal to N.

[0021] S5. First determine the difference matrix Q3 = Q2-Q1 between the pairing matrix of the incoming wave direction and the pairing matrix of the arrival time difference, and then determine whether the element with the smallest absolute value among all elements of the v-th row vector of the matrix Q3 is the u-th row vector. v elements, v and u v are all integers greater than or equal to 1 and less than or equal to N, so the bi-station distance vector of the vth scattering point is determined as

[0022]

[0023] S6. Finally, determine the two-dimensional rectangular coordinate vector of the radiation source as

[0024]

[0025] Where r0(1) is the first element of the distance vector r0 between the two stations of the radiation source; the two-dimensional rectangular coordinate vector of the vth scattering point is determined as

[0026]

[0027] Among them, r v (1) is the bistatic distance vector r of the vth scattering point v The first element of , thereby determining the joint positioning result of the radiation source and the scattering point.

[0028] The beneficial effects of the present invention are as follows: in the case of aliasing of multiple incoming wave signals in the time domain and frequency domain, the dual-station direction-finding cross-positioning method has positioning ambiguity. Although the multi-station direction-finding cross-positioning method can resolve the positioning ambiguity, it is necessary to increase the number of auxiliary stations, which increases the complexity and cost of the passive positioning system; the method of the present invention utilizes a main station passive detection device and an auxiliary station master station passive detection device to measure the direction of incoming waves and the time difference of arrival, and only uses two stations to realize the joint positioning of the radiation source and the scattering point, which can be used for application scenarios where there is a radiation source with a radiation signal and multiple scattering points that scatter the radiation signal of the radiation source in the detection area. DETAILED DESCRIPTION

[0029] The practicability of the present invention will be described below with reference to the embodiments.

[0030] Example

[0031] The two-dimensional rectangular coordinate vectors of the two passive detection devices of the master station and the auxiliary station are set to be p1 = [-7699.1; 749.8] and p2 = [7635.1; 835.2] respectively; there is a radiation source of a radiation signal and three scattering points that scatter the radiation signal of the radiation source in the detection area. The direct wave signal of the radiation source that arrives earliest as determined by the master station is in the direction of 34.1 degrees. The scattered wave signals of the three scattering points that scatter the radiation signal of the radiation source as determined by the master station are in the directions of 80.4 degrees, 69.1 degrees and 55.2 degrees respectively. The arrival time differences of the direct wave signals radiated by the source are 163377.5 nanoseconds, 210890.7 nanoseconds and 319870.0 nanoseconds respectively; the direction of the direct wave signal radiated by the earliest arriving radiation source determined by the auxiliary station is 161.9 degrees, and the directions of the scattered signals of the three scattering points that scatter the radiation signal of the radiation source determined by the auxiliary station are 111.2 degrees, 92.3 degrees and 70.4 degrees respectively, and the arrival time differences relative to the direct wave signal radiated by the earliest arriving radiation source are 152660.6 nanoseconds, 188239.6 nanoseconds and 281767.5 nanoseconds respectively.

[0032] Using the combined positioning method of radiation source and scattering point proposed in the present invention, the two-dimensional rectangular coordinate vector of the radiation source is determined to be [-2599.8; 4201.4]. Compared with the actual two-dimensional rectangular coordinate vector of the radiation source [-2620.8; 4204.7], the positioning error is 21.3 meters. The relative positioning error is 0.4% relative to the distance from the radiation source to the main station. The two-dimensional rectangular coordinate vectors of the three scattering points are determined to be [-3012.5; 28482.4], [6253.7; 37269.2] and [ 23851.9; 46197.7], compared with the actual two-dimensional rectangular coordinate vectors of the three scattering points [-2560.3; 29760.7], [5807.3; 35671.8] and [23625.6; 44856.2], the positioning errors are 1355.9, 1658.6 and 1360.5 meters respectively. Relative to the distance from the scattering point to the main station, the relative positioning errors are 4.6%, 4.4% and 2.5% respectively. It can be seen that the method of the present invention can realize the joint positioning of the radiation source and the scattering point.

Claims

1. A method for jointly locating a radiation source and a scattering point, characterized in that: The positioning method is to detect the radiation source through the main station and the auxiliary station, and at the same time, there are N scattering points in the detection area, and the scattering points scatter the signal of the radiation source. The main station and the auxiliary station receive the scattered signals of the scattering points while receiving the direct wave signal of the radiation source, so as to realize the joint positioning of the radiation source and the scattering points. Specifically, it includes: S1. Assume that the two-dimensional rectangular coordinate vectors of the two passive detection devices of the master station and the auxiliary station are p1 and p2 respectively. After the detection starts, define the direction of the direct wave signal of the earliest arriving radiation source determined by the master station as θ 1,0 The direction of the scattered signal from the nth scattering point determined by the master station is θ 1,n The arrival time difference of the scattered signal relative to the earliest direct wave signal is τ 1,n , n is the sequence number of the scattered signal direction and arrival time difference determined by the master station, which is an integer greater than or equal to 1 and less than or equal to N; the direction of the direct wave signal of the earliest arriving radiation source determined by the slave station is θ 2,0 The direction of the scattered signal from the kth scattering point determined by the auxiliary station is θ 2,k The arrival time difference of the scattered signal relative to the earliest direct wave signal is τ 2,k , k is the serial number of the direction and arrival time difference of the scattered signal determined by the auxiliary station, which is an integer greater than or equal to 1 and less than or equal to N; S2, using θ 1,0 and θ 2,0 , determine the distance vector between the two stations of the radiation source as in,[] -1 represents the inverse matrix; S3. Using θ 1,n and θ 2,k , determine the pairing vector of the incoming wave direction of the primary station and the secondary station as Thus, the pairing matrix Q1 of the incoming wave direction of the primary station and the secondary station is determined, and its n-th row and k-th column element Q1(n,k) is Q1(n,k)=1 T (r n,k -r0); Among them, 1 T represents a two-dimensional row vector whose elements are all equal to 1; S4. Using τ 1,n and τ 2,k , determine the pairing matrix Q2 of the arrival time difference between the primary station and the secondary station, whose nth row and kth column element Q2(n,k) is Q2(n,k)=c(τ 1,n -t 2,k ); Where, is the speed of light; S5, first determine the difference matrix Q3 = Q2-Q1 between the pairing matrix of the incoming wave direction and the pairing matrix of the arrival time difference, and then determine the u-th row vector with the smallest absolute value among all elements of the v-th row vector of the matrix Q3. v elements, v and u v are all integers greater than or equal to 1 and less than or equal to N, so the bi-station distance vector of the vth scattering point is determined as S6. Finally, determine the two-dimensional rectangular coordinate vector of the radiation source as Where r0(1) is the first element of the distance vector r0 between the two stations of the radiation source; the two-dimensional rectangular coordinate vector of the vth scattering point is determined as Among them, r v (1) is the bistatic distance vector r of the vth scattering point v The first element of , thereby determining the joint positioning result of the radiation source and the scattering point.

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