Positioning device and positioning method

Abstract

Provided is a positioning device comprising: a plurality of signal reception units (301) that are provided to a respective plurality of satellites (1) and that acquire complex signal vectors of signals received by said satellites (1); a correlation processing unit (302) that calculates information pertaining to TDOA and FDOA by correlation processing between said complex signal vectors; a ground control point calculation unit (303) that calculates ground control points corresponding to said TDOA and FDOA; a coordinate transformation unit (306) that transforms said ground control points into information pertaining to latitude and longitude; a frequency distribution calculation unit (307) that calculates a frequency distribution of ground control points; a ground control point extraction unit (308) that extracts, from said frequency distribution, a ground control point included in a region having the greatest frequency; and a position estimation unit that estimates the position of a target radio source (10). Also provided is a positioning method.

Description

[Technical Field]

[0001] The present disclosure relates to a positioning device and a positioning method for locating an unknown target radio wave source. [Background technology]

[0002] Positioning of unknown target radio wave sources using satellites has traditionally been performed using correlation processing between signals received by the satellites, followed by information on the time difference of arrival (TDOA) and frequency difference (FDOA) of the signals (see, for example, Non-Patent Document 1).

[0003] On the other hand, if an unknown target radio wave source emits radar waves, such as pulse waves, multiple candidate TDOA and FDOA information will be generated, which will result in ambiguity in the positioning results, making it difficult to estimate the true location of the target radio wave source. As a countermeasure, a method has been proposed in which an array antenna for azimuth estimation is mounted on a satellite, and ambiguity is eliminated using azimuth information to estimate the position of the target radio wave source (see, for example, Non-Patent Document 2). [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] dp Haworth, “Interference localization for eutelsat satellites-the first european transmitter location system” International journal of satellite communications, vol. 15, 155-183 (1997). [Non-patent document 2] Amishima, Fukushima, Takahashi, "Radar Pulse Ambiguity Rejection Using DOA in TDOA / FDOA Positioning Using Two Satellites," IEICE Technical Report SANE2022 Summary of the Invention [Problem to be solved by the invention]

[0005] In this way, the method using azimuth information can extract a control point originating from a target radio wave source from among multiple ambiguities. However, this method requires information on the direction of the target radio wave source, which poses a problem of increased hardware scale and cost due to the need to install an array antenna to acquire this information.

[0006] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a positioning device that can locate an unknown target radio wave source without using directional information, regardless of the type of the target radio wave source. [Means for solving the problem]

[0007] A positioning device according to the present disclosure includes: a plurality of signal receiving units provided for each of a plurality of satellites, each of which acquires complex signal vectors of signals received by the satellites; a correlation processing unit that calculates TDOA and FDOA information by correlation processing between the complex signal vectors based on the complex signal vectors acquired by the signal receiving units; a control point calculation unit that calculates control points corresponding to the TDOA and FDOA based on the TDOA and FDOA information calculated by the correlation processing unit; a coordinate conversion unit that converts the control points into latitude and longitude information based on the control points for a plurality of times calculated by the control point calculation unit; a frequency distribution calculation unit that calculates a frequency distribution of the control points based on the latitude and longitude information obtained by the coordinate conversion unit; a control point extraction unit that extracts control points included in an area with the maximum frequency from the frequency distribution based on the frequency distribution calculated by the frequency distribution calculation unit; and a position estimation unit that estimates a position of a target radio wave source based on the control points extracted by the control point extraction unit. The position estimation unit has an error ellipse calculation unit that calculates, for each pair of satellites, an error ellipse that is an area where the orientation point may exist, based on the orientation points extracted by the orientation point extraction unit; a common part calculation unit that extracts orientation points that exist in common parts of the error ellipses based on the error ellipses calculated by the error ellipse calculation unit; and a centroid calculation unit that sets the centroid of the orientation point as the position of the target radio wave source, based on the orientation points extracted by the common part calculation unit. . [Effects of the Invention]

[0008] According to the present disclosure, with the above-described configuration, it is possible to locate the position of an unknown target radio wave source without using azimuth information, regardless of the type of the target radio wave source. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a block diagram showing a schematic configuration example of a positioning system including a positioning device according to a first embodiment. [Figure 2] 1 is a block diagram showing a schematic configuration example of a positioning device according to a first embodiment. [Figure 3] 4 is a flowchart schematically illustrating an example of an operation procedure of the positioning device according to the first embodiment. [Figure 4] FIG. 3 is a diagram showing an example of a frequency distribution created by a frequency distribution calculation unit in the first embodiment. [Figure 5] FIG. 2 is a diagram for explaining an example of an outline of the operation of a orientation point extraction unit in the first embodiment. [Figure 6] FIG. 2 is a diagram for explaining the reason why the orientation point extraction unit in the first embodiment extracts orientation points included in areas with the highest frequency. [Figure 7] FIG. 10 is a diagram showing an example of values ​​of γ2 used in the error ellipse calculation unit according to the first embodiment and the probability that the orientation point corresponding to each value exists within the error ellipse. [Figure 8] FIG. 4 is a diagram illustrating an example of the operation of an error ellipse calculation unit according to the first embodiment. [Figure 9] FIG. 10 is a diagram illustrating an example of the operation of a common part calculation unit according to the first embodiment. [Figure 10] FIG. 10 is a block diagram showing a schematic configuration example of a positioning system including a positioning device according to a second embodiment. [Figure 11] FIG. 10 is a block diagram showing a schematic configuration example of a positioning device according to a second embodiment. [Figure 12] 10 is a flowchart schematically illustrating an example of an operation procedure of the positioning device according to the second embodiment. [Figure 13] FIG. 11 is a block diagram showing a schematic configuration example of a positioning system including a positioning device according to a third embodiment. [Figure 14] FIG. 10 is a block diagram showing a schematic configuration example of a positioning device according to a third embodiment. [Figure 15] 11 is a flowchart schematically illustrating an example of an operation procedure of a positioning device according to a third embodiment. [Figure 16] 1 is a block diagram schematically illustrating an example of a hardware configuration for realizing a positioning device according to first to third embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments will be described in detail with reference to the drawings. Note that components with the same reference numerals throughout the drawings have the same configurations and functions. Embodiment 1 FIG. 1 is a block diagram showing an example of a schematic configuration of a positioning system including a positioning device 3 according to the first embodiment. As shown in Fig. 1, the positioning system includes multiple satellites 1, multiple ground station antennas 2, and a positioning device 3. In addition to the positioning system, Fig. 1 also shows a target radio wave source 10, which is the object of positioning. This target radio wave source 10 is a radio wave source whose position is unknown.

[0011] The number of ground station antennas 2 provided corresponds to the number of satellites 1. Figure 2 shows a case where three satellites 1-#1 to 1-#3 are provided as the satellites 1, and three ground station antennas 2-#1 to 2-#3 are provided as the ground station antennas 2.

[0012] The satellite 1 receives a signal from a target radio source 10 . The signals received by this satellite 1 are transmitted to a ground station antenna 2 .

[0013] In Fig. 1, a satellite 1-#1 receives a signal from a target radio wave source 10. The signal received by the satellite 1-#1 is transmitted to a ground station antenna 2-#1. The satellite 1-#2 also receives a signal from the target radio wave source 10. The signal received by the satellite 1-#2 is transmitted to the ground station antenna 2-#2. The satellite 1-#3 also receives a signal from the target radio wave source 10. The signal received by the satellite 1-#3 is transmitted to the ground station antenna 2-#3.

[0014] A ground station antenna 2 receives the signals received by the satellite 1 . The signal received by this ground station antenna 2 is transmitted to a positioning device 3 .

[0015] 1, a ground station antenna 2-#1 receives a signal received by a satellite 1-#1. The signal received by the ground station antenna 2-#1 is transmitted to a positioning device 3. Furthermore, the ground station antenna 2-#2 receives the signal received by the satellite 1-#2. The signal received by the ground station antenna 2-#2 is transmitted to the positioning device 3. The ground station antenna 2-#3 receives the signal received by the satellite 1-#3. The signal received by the ground station antenna 2-#3 is transmitted to the positioning device 3.

[0016] The positioning device 3 locates the position of the target radio wave source 10 using TDOA and FDOA information calculated by correlation processing of signals received by each satellite 1. This positioning device 3 can be applied to various fields such as radar systems and satellite communication systems. As shown in FIG. 2, this positioning device 3 includes a plurality of signal receiving units 301, a correlation processing unit 302, a control point calculation unit 303, a control point accumulation unit 304, an accumulation time determination unit 305, a coordinate conversion unit 306, a frequency distribution calculation unit 307, a control point extraction unit 308, an error ellipse calculation unit 309, a common part calculation unit 310, and a centroid calculation unit 311.

[0017] The number of signal receiving units 301 provided corresponds to the number of satellites 1. Fig. 2 shows a case where three signal receiving units 301, 301-#1 to 301-#3, are provided as signal receiving units 301. 2, the correlation processing unit 302 has correlation processing units 302-#1 to 302-#3 corresponding to the set of satellites 1. Also, in FIG. 2, the orientation point calculation unit 303 has orientation point calculation units 303-#1 to 303-#3 corresponding to the set of satellites 1.

[0018] The signal receiving unit 301 obtains the complex signal vector of the signal received by the corresponding satellite 1 based on the signal received by the corresponding ground station antenna 2 . Specifically, first, the signal receiving unit 301 generates an analog signal by performing various signal processing such as amplification, band-pass filtering, and frequency conversion on the RF (radio frequency) output of the terrestrial station antenna 2. This analog signal is a complex signal having an in-phase component and a quadrature component. Then, the signal receiving unit 301 converts this analog signal into a received signal, which is a digital complex signal, to obtain a complex signal vector. The signal indicating the complex signal vector acquired by the signal receiving unit 301 is output to the correlation processing unit 302 .

[0019] 2, the signal receiving unit 301-#1 acquires the complex signal vector x1(t) of the signal received by the satellite 1-#1 based on the signal received by the terrestrial station antenna 2-#1. The signal representing the complex signal vector x1(t) acquired by the signal receiving unit 301-#1 is output to the correlation processing unit 302-#1 and the correlation processing unit 302-#3. Furthermore, the signal receiving unit 301-#2 acquires the complex signal vector x2(t) of the signal received by the satellite 1-#2 based on the signal received by the terrestrial station antenna 2-#2. The signal indicating the complex signal vector x2(t) acquired by the signal receiving unit 301-#2 is output to the correlation processing unit 302-#1 and the correlation processing unit 302-#2. Furthermore, the signal receiving unit 301-#3 acquires the complex signal vector x3(t) of the signal received by the satellite 1-#3 based on the signal received by the terrestrial station antenna 2-#3. The signal indicating the complex signal vector x3(t) acquired by the signal receiving unit 301-#3 is output to the correlation processing unit 302-#2 and the correlation processing unit 302-#3.

[0020] The correlation processing unit 302 calculates TDOA and FDOA information based on the complex signal vectors acquired by each signal receiving unit 301 by performing correlation processing between the complex signal vectors. Specifically, the correlation processor 302 calculates TDOA and FDOA information by extracting peak values ​​of a CAF (Cross Ambiguity Function) as a correlation process between the complex signal vectors in accordance with the method described in Non-Patent Document 1. Note that if the target radio wave source 10 is a radar wave source, there will be multiple peak values ​​of the CAF, and as a result, multiple pieces of TDOA and FDOA information will be calculated. A signal indicating the TDOA and FDOA information calculated by the correlation processing unit 302 is output to the orientation point calculation unit 303.

[0021] In FIG. 2, the correlation processor 302-#1 calculates the TDOAτ by performing correlation processing between the complex signal vectors x1(t) and x2(t) based on the complex signal vector x1(t) acquired by the signal receiver 301-#1 and the complex signal vector x2(t) acquired by the signal receiver 301-#2. 12(i) and FDOAf 12(i) The correlation processor 302-#1 calculates the information of TDOAτ 12(i) and FDOAf 12(i) A signal indicating this information is output to the orientation point calculation unit 303-#1. Furthermore, the correlation processing unit 302-#2 calculates the TDOAτ by performing correlation processing between the complex signal vectors x2(t) and x3(t) based on the complex signal vector x2(t) acquired by the signal receiving unit 301-#2 and the complex signal vector x3(t) acquired by the signal receiving unit 301-#3. 23(j) and FDOAf 23(j)The correlation processor 302-#2 calculates the information of TDOAτ 23(j) and FDOAf 23(j) A signal indicating this information is output to the orientation point calculation unit 303-#2. Furthermore, the correlation processing unit 302-#3 calculates the TDOAτ by performing correlation processing between the complex signal vectors x1(t) and x3(t) based on the complex signal vector x1(t) acquired by the signal receiving unit 301-#1 and the complex signal vector x3(t) acquired by the signal receiving unit 301-#3. 13(k) and FDOAf 13(k) The correlation processor 302-#3 calculates the information of TDOAτ 13(k) and FDOAf 13(k) A signal indicating this information is output to the orientation point calculation unit 303-#3.

[0022] Note that i, j, and k each represent a positive integer. The number of peak values ​​of CAF calculated from the received signals between satellites 1-#1 and 1-#3 is N 12 ,N 23 ,N 13 Then, i, j, k are 1≦i≦N 12 ,1≦j≦N 23 ,1≦k≦N 13 Satisfies the range.

[0023] The orientation point calculation unit 303 performs position location processing using the information on the TDOA and FDOA calculated by the correlation processing unit 302, thereby obtaining orientation points corresponding to the TDOA and FDOA. A signal indicating the orientation point calculated by the orientation point calculation unit 303 is output to the orientation point accumulation unit 304.

[0024] In FIG. 2, the orientation point calculation unit 303#1 calculates the TDOAτ 12(i) and FDOAf 12(i) By performing position location processing using the information of 12(i) and FDOAf 12(i) The control point p corresponding to 12(i) The orientation point p calculated by the orientation point calculation unit 303-#1 is calculated.12(i) The signal indicating this is output to the orientation point storage unit 304. The control point calculation unit 303-#2 calculates the TDOAτ 23(j) and FDOAf 23(j) By performing position location processing using the information of 23(j) and FDOAf 23(j) The control point p corresponding to 23(j) The orientation point p calculated by the orientation point calculation unit 303-#2 is calculated. 23(j) The signal indicating this is output to the orientation point storage unit 304. The control point calculation unit 303-#3 calculates the TDOAτ 13(k) and FDOAf 13(k) By performing position location processing using the information of 13(k) and FDOAf 13(k) The control point p corresponding to 13(k) The orientation point p calculated by the orientation point calculation unit 303-#3 is calculated. 13(k) The signal indicating this is output to the orientation point storage unit 304.

[0025] The orientation point calculation unit 303 calculates an orientation point corresponding to a set of TDOA and FDOA. 12 The orientation point calculation unit 303-#2 calculates N orientation points. 23 The orientation point calculation unit 303-#3 calculates N orientation points. 13 Calculate the orientation points.

[0026] The orientation point storage unit 304 stores information indicating the orientation points calculated by each orientation point calculation unit 303. The orientation point storage unit 304 continues storage when the storage time determination unit 305 determines that the elapsed time of storage has not reached the storage time. On the other hand, when the storage time determination unit 305 determines that the elapsed time of storage has reached the storage time, the orientation point storage unit 304 outputs a signal indicating the stored orientation points to the coordinate conversion unit 306.

[0027] In FIG. 2, the orientation point accumulation unit 304 collects the orientation points calculated by the orientation point calculation unit 303-#1, the orientation points calculated by the orientation point calculation unit 303-#2, and the orientation points calculated by the orientation point calculation unit 303-#3 into one, and stores the set of orientation points p all =[p 12(i) ,p 23 (j) ,p 13(k) ] and store it. Then, when the accumulation time determination unit 305 determines that the elapsed time of accumulation has not reached the accumulation time, the orientation point accumulation unit 304 performs p all Continue accumulating p all-T On the other hand, when the accumulation time determination unit 305 determines that the elapsed time of accumulation has reached the accumulation time, the orientation point accumulation unit 304 updates the accumulated p all-T to the coordinate conversion unit 306.

[0028] The accumulation time determination unit 305 determines whether the elapsed time of accumulation by the orientation point accumulation unit 304 has reached a preset accumulation time. Specifically, the accumulation time determination unit 305 sets the time when acquisition of the orientation points starts at 0, measures the elapsed time t from that time, and determines whether a preset accumulation time T has been reached.

[0029] 2 shows a case where the control point accumulation unit 304 and accumulation time determination unit 305 are provided inside the positioning device 3. However, the present invention is not limited to this, and the control point accumulation unit 304 and accumulation time determination unit 305 may be provided outside the positioning device 3.

[0030] The coordinate conversion unit 306 converts the control points indicated by the information accumulated for multiple hours by the control point accumulation unit 304 into information of latitude and longitude. A signal indicating the latitude and longitude information obtained by the coordinate conversion unit 306 is output to the frequency distribution calculation unit 307 .

[0031] In FIG. 2, the coordinate conversion unit 306 converts p stored for multiple time periods by the control point storage unit 304. all-T The three-dimensional vector information of each control point stored in is converted into latitude φ and longitude θ information p all-T-latlon The information p of latitude φ and longitude θ obtained by the coordinate conversion unit 306 is all-T-latlon The signal indicating this is output to the frequency distribution calculation unit 307.

[0032] The frequency distribution calculation unit 307 calculates the frequency distribution of the control points based on the latitude and longitude information obtained by the coordinate conversion unit 306. The frequency distribution of the control points is a distribution for evaluating the density of the control points. A signal indicating the frequency distribution calculated by the frequency distribution calculation unit 307 is output to the orientation point extraction unit 308.

[0033] The control point extraction unit 308 extracts control points included in the area with the maximum frequency from the frequency distribution based on the frequency distribution calculated by the frequency distribution calculation unit 307. The control points extracted by the control point extraction unit 308 are candidates for control points originating from the target radio wave source 10. A signal indicating the orientation points extracted by the orientation point extraction unit 308 is output to an error ellipse calculation unit 309 .

[0034] In FIG. 2, based on the frequency distribution calculated by the frequency distribution calculation unit 307, the control point extraction unit 308 extracts the control point p corresponding to the set of satellites 1-#1 to 1-#3 as the control point included in the region with the maximum frequency from the frequency distribution. ext-12 ,p ext-23 ,p ext-13 Extract.

[0035] The error ellipse calculation unit 309 calculates an error ellipse, which is an area where the orientation point may exist, for each pair of satellites 1 based on the orientation points extracted by the orientation point extraction unit 308. A signal indicating the error ellipse calculated by the error ellipse calculation unit 309 is output to the common part calculation unit 310 .

[0036] In FIG. 2, the error ellipse calculation unit 309 calculates the error ellipse of the orientation point p extracted by the orientation point extraction unit 308. e xt-12 ,pext-23 ,p ext-13 Based on this, for each set of satellites 1-#1 to 1-#3, the control point p ext-12 ,p ext-23 ,p ext-13 The error ellipse calculation unit 309 calculates an error ellipse, which is an area where the error ellipse may exist. A signal indicating the error ellipse calculated by the error ellipse calculation unit 309 is output to the common part calculation unit 310.

[0037] Based on the error ellipses calculated by the error ellipse calculation section 309, the common part calculation section 310 extracts orientation points that exist in the overlapping area, which is the common part of the error ellipses. A signal indicating the orientation point extracted by the common part calculation unit 310 is output to the center of gravity calculation unit 311.

[0038] Based on the orientation points extracted by the common part calculation section 310, the centroid calculation section 311 determines the centroid of the orientation points as the position of the target radio wave source 10. A signal indicating the position of the target radio wave source 10 estimated by this center of gravity calculation unit 311 is output to the outside.

[0039] The error ellipse calculation unit 309, the common part calculation unit 310, and the center of gravity calculation unit 311 constitute a "position estimation unit that estimates the position of the target radio wave source 10 based on the control point extracted by the control point extraction unit 308." 2 shows a case where the position estimation unit includes an error ellipse calculation unit 309, a common part calculation unit 310, and a centroid calculation unit 311. However, the present invention is not limited to this, and the position estimation unit may have any configuration as long as it is capable of estimating the position of the target radio wave source 10 based on the control points extracted by the control point extraction unit 308.

[0040] Next, an example of the operation of the positioning device 3 according to the first embodiment shown in FIG. 2 will be described with reference to FIG. In an example of operation of the positioning device 3 according to embodiment 1 shown in FIG. 2, as shown in FIG. 3, first, the signal receiving unit 301 acquires a complex signal vector of the signal received by the corresponding satellite 1 based on the signal received by the corresponding terrestrial station antenna 2 (step ST101). Specifically, first, the signal receiving unit 301 generates an analog signal by performing various signal processing such as amplification, band-pass filtering, and frequency conversion on the RF (radio frequency) output of the terrestrial station antenna 2. This analog signal is a complex signal having an in-phase component and a quadrature component. Then, the signal receiving unit 301 converts this analog signal into a received signal, which is a digital complex signal, to obtain a complex signal vector. The signal indicating the complex signal vector acquired by the signal receiving unit 301 is output to the correlation processing unit 302 .

[0041] 2, the signal receiving unit 301-#1 acquires the complex signal vector x1(t) of the signal received by the satellite 1-#1 based on the signal received by the terrestrial station antenna 2-#1. The signal representing the complex signal vector x1(t) acquired by the signal receiving unit 301-#1 is output to the correlation processing unit 302-#1 and the correlation processing unit 302-#3. Furthermore, the signal receiving unit 301-#2 acquires the complex signal vector x2(t) of the signal received by the satellite 1-#2 based on the signal received by the terrestrial station antenna 2-#2. The signal indicating the complex signal vector x2(t) acquired by the signal receiving unit 301-#2 is output to the correlation processing unit 302-#1 and the correlation processing unit 302-#2. Furthermore, the signal receiving unit 301-#3 acquires the complex signal vector x3(t) of the signal received by the satellite 1-#3 based on the signal received by the terrestrial station antenna 2-#3. The signal indicating the complex signal vector x3(t) acquired by the signal receiving unit 301-#3 is output to the correlation processing unit 302-#2 and the correlation processing unit 302-#3.

[0042] Next, based on the complex signal vectors acquired by each signal receiving unit 301, the correlation processing unit 302 calculates information on TDOA and FDOA by correlation processing between the complex signal vectors (step ST102). Specifically, the correlation processor 302 calculates TDOA and FDOA information by extracting peak values ​​of CAF as correlation processing between the complex signal vectors according to the method described in Non-Patent Document 1. Note that if the target radio wave source 10 is a radar wave source, there will be multiple peak values ​​of CAF, and as a result, multiple pieces of TDOA and FDOA information will be calculated. A signal indicating the TDOA and FDOA information calculated by the correlation processing unit 302 is output to the orientation point calculation unit 303.

[0043] In FIG. 2, the correlation processor 302-#1 calculates the TDOAτ by performing correlation processing between the complex signal vectors x1(t) and x2(t) based on the complex signal vector x1(t) acquired by the signal receiver 301-#1 and the complex signal vector x2(t) acquired by the signal receiver 301-#2. 12(i) and FDOAf 12(i) The correlation processor 302-#1 calculates the information of TDOAτ 12(i) and FDOAf 12(i) A signal indicating this information is output to the orientation point calculation unit 303-#1. Furthermore, the correlation processing unit 302-#2 calculates the TDOAτ by performing correlation processing between the complex signal vectors x2(t) and x3(t) based on the complex signal vector x2(t) acquired by the signal receiving unit 301-#2 and the complex signal vector x3(t) acquired by the signal receiving unit 301-#3. 23(j) and FDOAf 23(j) The correlation processor 302-#2 calculates the information of TDOAτ 23(j) and FDOAf 23(j) A signal indicating this information is output to the orientation point calculation unit 303-#2. Furthermore, the correlation processing unit 302-#3 calculates the TDOAτ by performing correlation processing between the complex signal vectors x1(t) and x3(t) based on the complex signal vector x1(t) acquired by the signal receiving unit 301-#1 and the complex signal vector x3(t) acquired by the signal receiving unit 301-#3. 13(k) and FDOAf 13(k) The correlation processor 302-#3 calculates the information of TDOAτ 13(k)and FDOAf 13(k) A signal indicating this information is output to the orientation point calculation unit 303-#3.

[0044] Next, the orientation point calculation unit 303 performs position location processing using the information on the TDOA and FDOA calculated by the correlation processing unit 302, thereby obtaining an orientation point corresponding to the TDOA and FDOA (step ST103). A signal indicating the orientation point calculated by the orientation point calculation unit 303 is output to the orientation point accumulation unit 304.

[0045] In FIG. 2, the orientation point calculation unit 303#1 calculates the TDOAτ 12(i) and FDOAf 12(i) By performing position location processing using the information of 12(i) and FDOAf 12(i) The control point p corresponding to 12(i) Specifically, the orientation point calculation unit 303-#1 calculates the orientation point p by solving simultaneous equations using the following expressions (1), (2), and (7). 12(i) The orientation point p calculated by the orientation point calculation unit 303-#1 is calculated. 12(i) The signal indicating this is output to the orientation point storage unit 304. The control point calculation unit 303-#2 calculates the TDOAτ 23(j) and FDOAf 23(j) By performing position location processing using the information of 23(j) and FDOAf 23(j) The control point p corresponding to 23(j) Specifically, the orientation point calculation unit 303-#1 calculates the orientation point p by solving simultaneous equations using the following expressions (3), (4), and (7). 23(j) The orientation point p calculated by the orientation point calculation unit 303-#2 is calculated. 23(j) The signal indicating this is output to the orientation point storage unit 304. The control point calculation unit 303-#3 calculates the TDOAτ 13(k) and FDOAf 13(k) By performing position location processing using the information of13(k) and FDOAf 13(k) The control point p corresponding to 13(k) Specifically, the orientation point calculation unit 303-#1 calculates the orientation point p by solving the simultaneous equations (5), (6), and (7) below. 13(k) The orientation point p calculated by the orientation point calculation unit 303-#3 is calculated. 13(k) The signal indicating this is output to the orientation point storage unit 304.

[0046] In equations (1) to (7), c represents the speed of light, and p s1 indicates the position vector of satellite 1-♯1, and p s2 indicates the position vector of satellite 1-♯2, and p s3 indicates the position vector of satellite 1-♯3, and v s1 indicates the velocity vector of satellite 1-♯1, and v s2 indicates the velocity vector of satellite 1-♯2, and v s3 indicates the velocity vector of satellite 1-♯3, and R E indicates the radius of the Earth when it is considered a sphere, and f0 indicates the center frequency of the received signal. TIFF0007734880000001.tif145166

[0047] Note that there are methods for solving the above simultaneous equations, such as a method of finding a solution through iterative calculations, such as Newton's method or steepest descent method, and a method of finding the solution as the root of a polynomial, as described in Non-Patent Document 3, for example. The orientation point calculation unit 303 may use either method. [Non-patent document 3] K C. Ho and YT Chan, “Geolocation of a known altitude known object from TDOA and FDOA measurements” in IEEE Transactions on Aerospace and Electronic Systems, vol. 33, no. 3, pp. 770-783, July 1997

[0048] Next, the reference point accumulation unit 304 accumulates information indicating the reference points calculated by each reference point calculation unit 303 for a certain period of time (step ST104). That is, when the accumulation time determination unit 305 determines that the elapsed time of accumulation has not reached the accumulation time, the reference point accumulation unit 304 continues the accumulation. On the other hand, when the accumulation time determination unit 305 determines that the elapsed time of accumulation has reached the accumulation time, the reference point accumulation unit 304 outputs a signal indicating the accumulated reference points to the coordinate conversion unit 306.

[0049] In FIG. 2, the reference point accumulation unit 304 combines the reference points calculated by the reference point calculation unit 303-♯1, the reference points calculated by the reference point calculation unit 303-♯2, and the reference points calculated by the reference point calculation unit 303-♯3 into a single set of reference points p all =[p 12(i) ,p 23 (j) ,p 13(k) and accumulates this. Then, when the accumulation time determination unit determines that the elapsed time of accumulation has not reached the accumulation time (when t < T), the reference point accumulation unit 304 continues the accumulation of p all and updates it as p all-T . On the other hand, when the accumulation time determination unit 305 determines that the elapsed time t of accumulation has reached the accumulation time T (when t ≥ T), the reference point accumulation unit 304 outputs a signal indicating the accumulated p all-T to the coordinate conversion unit 306.

[0050] Next, the coordinate conversion unit 306 converts the reference points indicated by the information accumulated by the reference point accumulation unit 304 for a plurality of time periods into latitude and longitude information (step ST105). The signal indicating the latitude and longitude information obtained by the coordinate conversion unit 306 is output to the frequency distribution calculation unit 307.

[0051] In FIG. 2, the coordinate conversion unit 306 converts the three-dimensional vector information of each reference point stored in p a ll-T accumulated by the reference point accumulation unit 304 for a plurality of time periods into information on latitude φ and longitude θ pall-T-latlon The information p of latitude φ and longitude θ obtained by the coordinate conversion unit 306 is all-T-latlon The signal indicating this is output to the frequency distribution calculation unit 307.

[0052] Next, the frequency distribution calculation unit 307 calculates the frequency distribution of the control points based on the information of latitude and longitude obtained by the coordinate conversion unit 306 (step ST106). A signal indicating the frequency distribution calculated by the frequency distribution calculation unit 307 is output to the orientation point extraction unit 308.

[0053] At this time, the frequency distribution calculation unit 307 creates a frequency distribution such as that shown in FIG. Specifically, in the frequency distribution, the latitude φ direction is divided into M grids, and the longitude θ direction is divided into N grids, and for each area (hereinafter referred to as a cell) defined by each grid, the number of orientation points included in that area is stored.

[0054] Next, the control point extraction unit 308 extracts a control point included in the area with the maximum frequency from the frequency distribution calculated by the frequency distribution calculation unit 307 (step ST107). The control points extracted by the control point extraction unit 308 are candidates for control points originating from the unknown target radio wave source 10. A signal indicating the orientation points extracted by the orientation point extraction unit 308 is output to an error ellipse calculation unit 309 .

[0055] In FIG. 2, based on the frequency distribution calculated by the frequency distribution calculation unit 307, the control point extraction unit 308 extracts the control point p corresponding to the set of satellites 1-#1 to 1-#3 as the control point included in the region with the maximum frequency from the frequency distribution. ext-12 ,p ext-23 ,p ext-13 Extract.

[0056] For example, as shown in FIG. 5, if the area with the maximum frequency in the frequency distribution calculated by the frequency distribution calculation unit 307 is the cell (Δθ4, Δφ6) indicated by the symbol 51, the orientation point extraction unit 308 extracts the orientation point included in that cell.

[0057] Here, the reason why the orientation point extraction unit 308 extracts orientation points included in the area with the maximum frequency will be explained. When viewed at a single time, it is difficult to determine whether a control point calculated from a signal acquired by a radar wave source or the like originates from the true target radio wave source 10 or is an ambiguity. However, as shown in FIG. 6, when the accumulated results of control points over multiple time periods are viewed, the ambiguity fluctuates in accordance with the motion of the satellite 1, while the true target radio wave source 10 actually exists at that location, so the control point appears in the same location regardless of the motion of the satellite 1. Even if the target radio wave source 10 is moving, the speed is sufficiently small compared to the speed of the orbiting satellite 1. As a result, when viewed over multiple time periods, the behavior of the position fluctuation of the control point differs depending on whether it originates from the target radio wave source 10 or is an ambiguity. If it originates from the target radio wave source 10, it exhibits characteristics that are relatively close to a fixed point. In FIG. 6, reference numeral 61 denotes a control point originating from the target radio wave source 10, and reference numeral 62 denotes an ambiguity control point. In the positioning device 3 according to the first embodiment, by using this characteristic, it becomes possible to extract the control point originating from the target radio wave source 10 without using azimuth information.

[0058] Next, the error ellipse calculation unit 309 calculates an error ellipse, which is an area where the orientation point may exist, for each pair of satellites 1 based on the orientation points extracted by the orientation point extraction unit 308 (step ST108). A signal indicating the error ellipse calculated by the error ellipse calculation unit 309 is output to the common part calculation unit 310 .

[0059] In FIG. 2, the error ellipse calculation unit 309 calculates the error ellipse of the orientation point p extracted by the orientation point extraction unit 308. e xt-12 ,p ext-23 ,p ext-13 Based on this, for each set of satellites 1-#1 to 1-#3, the control point p ext-12 ,p ext-23 ,p ext-13The error ellipse calculation unit 309 calculates an error ellipse, which is an area where the error ellipse may exist. A signal indicating the error ellipse calculated by the error ellipse calculation unit 309 is output to the common part calculation unit 310.

[0060] Specifically, first, the error ellipse calculation unit 309 calculates an error covariance matrix R from each orientation point as shown in the following equations (8) to (10). 12 ,R 23 ,R 13 Ask for. In addition, in equations (8) to (10), p(bar) ext-12 HAp ext-12 indicates the center of gravity of p(bar) ext-23 HAp ext-23 indicates the center of gravity of p(bar) ext-1 3 is p ext-13 Also, γ 2 is a χ with two degrees of freedom 2 It is determined by a square distribution, and the probability of existence of the control point changes depending on the value, as shown in Figure 7. TIFF0007734880000002.tif56166

[0061] Next, the error ellipse calculation unit 309 calculates the axis length σ of the ellipse from the components of each covariance matrix as shown in the following equations (11) to (19). x12 ,σ y12 ,σ x23 ,σ y23 ,σ x13 ,σ y13 and the slope φ from the origin 12 ,φ 23 ,φ 13 Ask for. TIFF0007734880000003.tif193166

[0062] Next, the error ellipse calculation unit 309 calculates the axis length σ of the calculated ellipse using the following equations (20) to (28). x12 ,σ y12 ,σ x23 ,σ y23 ,σ x13 ,σ y13 and the slope φ from the origin 12 ,φ 23 ,φ 13For each ellipse, three constants that determine the equation of the ellipse are calculated using In addition, in the formulas (20) to (28), A 12 ,B 12 ,C 12 HAp ext-12 indicates the variables that determine the equation of the error ellipse that indicates the region where A may exist, 23 ,B 23 ,C 23 HAp ext-23 indicates the variables that determine the equation of the error ellipse that indicates the region where A may exist, 13 ,B 13 ,C 13 HAp ext-13 The variables determine the equation of the error ellipse that indicates the region where the error may exist. TIFF0007734880000004.tif191166

[0063] By calculating the constants of each ellipse, the equations of the ellipse in the latitude and longitude directions can be expressed as the following equations (29) to (31). In addition, in equations (29) to (31), θ(bar) 12 HAp(bar) ext-12 θ(bar) indicates the longitude coordinate of 23 HAp(bar) ext-23 θ(bar) indicates the longitude coordinate of 13 HAp(bar) ext-13 and φ (bar) 12 HAp(bar) ext-12 latitudinal coordinate of φ (bar) 23 HAp(bar) ext- 23 latitudinal coordinate of φ (bar) 13 HAp(bar) ext-13 This indicates the latitude coordinate of the TIFF0007734880000005.tif33166

[0064] Next, the error ellipse calculation unit 309 calculates the error ellipse using the information on the calculated ellipse equations expressed by the formulas (29), (30), and (31) and the information on the orientation points pext-1 2,p ext-23 ,p ext-13 to the common part calculation unit 310. An example of the operation of error ellipse calculation section 309 at this time is shown in Fig. 8. In Fig. 8, reference numerals 81 to 83 indicate error ellipses calculated by error ellipse calculation section 309.

[0065] Next, based on the error ellipses calculated by the error ellipse calculation section 309, the common part calculation section 310 extracts orientation points that exist in the overlapping area, which is the common part of the error ellipses (step ST109). A signal indicating the orientation point extracted by the common part calculation unit 310 is output to the center of gravity calculation unit 311.

[0066] In FIG. 2, the common part calculation unit 310 calculates p ext-12 ,p ext-23 ,p ext-1 3, only the orientation points that satisfy the conditions of the following expressions (32) to (34) are extracted. ext-12-23-13 The signal indicating this is output to the center of gravity calculation unit 311. TIFF0007734880000006.tif34166

[0067] The spread of the error ellipse is generally determined by the signal-to-noise ratio (SNR) of the received signal and the physical positional relationship between the satellite 1 and the target radio wave source 10. Therefore, depending on the conditions, the error of a specific ellipse among multiple ellipses may become relatively large. In that case, the error of p extracted by evaluating only the frequency distribution may be all-T-latlon When only the error ellipse is evaluated, the orientation error may increase due to the influence of orientation points that follow an error ellipse with a relatively large error. The processing in this common part calculation unit 310 extracts only the orientation points that exist in the common part of the error ellipses, thereby reducing the influence of a large error even when the orientation point calculated by a specific satellite 1 has a large error, and enabling robust orientation regardless of conditions. 9 shows an example of the operation of the common part calculation unit 310. In this Fig. 9, reference numeral 91 denotes a orientation point extracted by the common part calculation unit 310.

[0068] Next, based on the orientation points extracted by the common part calculation section 310, the centroid calculation section 311 determines the centroid of the orientation points as the position of the target radio wave source 10 (step ST110). A signal indicating the position of the target radio wave source 10 estimated by this center of gravity calculation unit 311 is output to the outside.

[0069] In FIG. 2, the centroid calculation unit 311 calculates the center of gravity of the orientation point p that exists in the common part of the error ellipses extracted by the common part calculation unit 310. ext-12-23-13 The center of gravity of the target radio source 10 is e xt Let's say. ext-12-23-13 The number of N ext-12-23-13 Then, p ext can be expressed as the following equation (35). TIFF0007734880000007.tif16166

[0070] In this way, the positioning device 3 according to the first embodiment utilizes the property that when control points are accumulated over time and the control points derived from the target radio wave source 10 are compared with the ambiguities, the control points derived from the target radio wave source 10 exhibit characteristics that are relatively close to fixed points. The positioning device 3 according to the first embodiment extracts a control point included in an area with the highest frequency from the frequency distribution of control points acquired over multiple times, and estimates the position of the target radio wave source 10 using this control point. As a result, the positioning device 3 according to the first embodiment can robustly estimate the position of the target radio wave source 10 without using azimuth information and regardless of the positional relationship of the satellites 1.

[0071] As described above, according to the first embodiment, the positioning device 3 includes a plurality of signal receiving units 301 provided for each of a plurality of satellites 1, each of which acquires a complex signal vector of a signal received by the satellite 1; a correlation processing unit 302 that calculates information on TDOA and FDOA by correlation processing between the complex signal vectors based on the complex signal vectors acquired by the signal receiving units 301; a control point calculation unit 303 that calculates control points corresponding to the TDOA and FDOA based on the information on TDOA and FDOA calculated by the correlation processing unit 302; The positioning device 3 according to the first embodiment includes a coordinate conversion unit 306 that converts the control points into latitude and longitude information based on the control points for multiple times calculated by the coordinate conversion unit 303, a frequency distribution calculation unit 307 that calculates a frequency distribution of the control points based on the latitude and longitude information obtained by the coordinate conversion unit 306, a control point extraction unit 308 that extracts control points included in an area with the maximum frequency from the frequency distribution based on the frequency distribution calculated by the frequency distribution calculation unit 307, and a position estimation unit that estimates the position of the target radio wave source 10 based on the control points extracted by the control point extraction unit 308. As a result, the positioning device 3 according to the first embodiment can locate the target radio wave source 10 without using direction information, regardless of the type of unknown target radio wave source 10. As a result, the positioning device 3 according to the first embodiment can avoid the increase in hardware size and cost that would be required in the past to install an array antenna for acquiring direction information.

[0072] Embodiment 2 The positioning device 3 according to the first embodiment is assumed to have a single target radio wave source 10. In contrast, the positioning device 3 according to the second embodiment is assumed to have a plurality of target radio wave sources 10.

[0073] FIG. 10 is a block diagram showing an example of a schematic configuration of a positioning system including a positioning device 3 according to the second embodiment. In the positioning system according to the first embodiment shown in FIG. 1, there is one target radio wave source 10 to be positioned, whereas in the positioning system according to the second embodiment shown in FIG. 10, there are multiple target radio wave sources 10 to be positioned.

[0074] FIG. 11 is a block diagram showing an example of a schematic configuration of a positioning device 3 according to the second embodiment. In the positioning device 3 according to the second embodiment shown in FIG. 11, the control point extraction unit 308 is changed to a control point extraction unit 312, and the error ellipse calculation unit 309, the common part calculation unit 310, and the center of gravity calculation unit 311 are each changed from singular to plural, compared to the positioning device 3 according to the first embodiment shown in FIG.

[0075] The control point extraction unit 312 calculates the number of areas where the frequency is equal to or greater than a threshold from the frequency distribution calculated by the frequency distribution calculation unit 307, and extracts control points included in the areas. In this way, the control point extraction unit 312 calculates the number of target radio wave sources 10, and extracts candidates for control points derived from the target radio wave sources 10. A signal indicating the orientation points extracted by the orientation point extraction unit 312 is output to the error ellipse calculation unit 309. In addition, a signal indicating the number calculated by the orientation point extraction unit 312 is output to the error ellipse calculation unit 309, the common part calculation unit 310, and the center of gravity calculation unit 311.

[0076] Furthermore, each error ellipse calculation unit 309 operates in parallel in the number calculated by the control point extraction unit 312, and calculates an error ellipse, which is an area where the control point may exist, for each pair of satellites 1 based on the control points extracted by the control point extraction unit 312. The operation of calculating the error ellipse by error ellipse calculation section 309 is the same as the operation of calculating the error ellipse by error ellipse calculation section 309 in the first embodiment.

[0077] In addition, each common part calculation unit 310 operates in parallel in the number calculated by the orientation point extraction unit 312, and extracts multiple orientation points that exist in the common part of the error ellipse based on the error ellipse calculated by the error ellipse calculation unit 309. The operation of calculating the error ellipse by error ellipse calculation section 309 is the same as the operation of calculating the error ellipse by error ellipse calculation section 309 in the first embodiment.

[0078] In addition, each center of gravity calculation unit 311 operates in parallel in the number calculated by the orientation point extraction unit 312, and calculates the center of gravity of the orientation point extracted by the common part calculation unit 310 as the target orientation point. The operation of calculating the error ellipse by error ellipse calculation section 309 is the same as the operation of calculating the error ellipse by error ellipse calculation section 309 in the first embodiment.

[0079] Next, an example of the operation of the positioning device 3 according to the second embodiment shown in FIG. 11 will be described with reference to FIG. The processing of steps ST201 to ST206 in the positioning device 3 according to the second embodiment shown in FIG. 12 is the same as the processing of steps ST101 to ST106 in the positioning device 3 according to the first embodiment shown in FIG.

[0080] Then, based on the frequency distribution calculated by the frequency distribution calculation unit 307, the control point extraction unit 312 calculates the number of areas where the frequency is equal to or greater than a threshold from the frequency distribution, and extracts control points included in the areas (step ST207). In this way, the control point extraction unit 312 estimates the number of target radio wave sources 10, and extracts candidates for control points derived from the target radio wave sources 10. A signal indicating the orientation points extracted by the orientation point extraction unit 312 is output to the error ellipse calculation unit 309. In addition, a signal indicating the number calculated by the orientation point extraction unit 312 is output to the error ellipse calculation unit 309, the common part calculation unit 310, and the center of gravity calculation unit 311.

[0081] Here, the area number in the longitude direction is k, and the area number in the latitude direction is l. In this case, the control point extraction unit 312 calculates the number N of latitude and longitude areas of the frequency distribution calculated by the frequency distribution calculation unit 307, which satisfies the following formula (36): tar is calculated and the control points included in the area are extracted. TIFF0007734880000008.tif13166

[0082] Then, the positioning device 3 extracts the set of (k, l) extracted by the control point extraction unit 312, that is, (k, l)=(k1, l1), (k2, l2), . . . , (k Ntar ,l Ntar ), the error ellipse calculation unit 309 performs the process of step ST208, the common part calculation unit 310 performs the process of step ST209, and the center of gravity calculation unit 311 performs the process of step ST210 in parallel, and N tar A signal indicating the minute estimation result is simultaneously output.

[0083] As described above, in the positioning device 3 according to the second embodiment, the control point extraction unit 312 is provided after the frequency distribution calculation unit 307 in the first embodiment. This makes it possible for the positioning device 3 according to the second embodiment to handle the case where a plurality of target radio wave sources 10 exist, and to simultaneously output signals indicating the positions of the respective target radio wave sources 10.

[0084] As described above, according to the second embodiment, the positioning device 3 includes a plurality of signal receiving units 301 provided for each of the plurality of satellites 1, each of which acquires a complex signal vector of a signal received by the corresponding satellite 1; a correlation processing unit 302 that calculates TDOA and FDOA information by correlation processing between the complex signal vectors based on the complex signal vectors acquired by the signal receiving units 301; a control point calculation unit 303 that calculates control points corresponding to the TDOA and FDOA based on the TDOA and FDOA information calculated by the correlation processing unit 302; The positioning device 3 according to the second embodiment includes a coordinate conversion unit 306 that converts the control points into latitude and longitude information based on the control points for a plurality of times output, a frequency distribution calculation unit 307 that calculates a frequency distribution of the control points based on the latitude and longitude information obtained by the coordinate conversion unit 306, a control point extraction unit 312 that calculates the number of areas where the frequency is equal to or greater than a threshold from the frequency distribution based on the frequency distribution calculated by the frequency distribution calculation unit 307 and extracts control points included in the areas, and a position estimation unit that estimates the position of the target radio wave source 10 based on the control points extracted by the control point extraction unit 312. As a result, the positioning device 3 according to the first embodiment has the effect of being able to locate each of the target radio wave sources 10 even when there are a plurality of target radio wave sources 10.

[0085] Embodiment 3 The positioning device 3 according to the third embodiment is configured to simultaneously receive a signal from a reference station 11 whose position is known in addition to a signal from a target radio wave source 10, thereby reducing the effects of time errors, frequency errors, etc. that occur within the satellite 1.

[0086] FIG. 13 is a block diagram showing an example of a schematic configuration of a positioning system including a positioning device 3 according to the third embodiment. The positioning system according to the first embodiment shown in FIG. 1 receives only a signal from the target radio wave source 10 to be positioned, whereas the positioning system according to the third embodiment shown in FIG. 13 receives a signal from the reference station 11 whose position is known in addition to the target radio wave source 10 to be positioned.

[0087] That is, the satellite 1 in the third embodiment receives a signal from the target radio wave source 10 and a signal from the reference station 11. The signals received by this satellite 1 are transmitted to a ground station antenna 2 .

[0088] 13, a satellite 1-#1 receives a signal from a target radio wave source 10 and a signal from a reference station 11. The signal received by this satellite 1-#1 is transmitted to a ground station antenna 2-#1. The satellite 1-#2 also receives a signal from the target radio wave source 10 and a signal from the reference station 11. The signal received by the satellite 1-#2 is transmitted to the ground station antenna 2-#2. The satellite 1-#3 also receives a signal from the target radio wave source 10 and a signal from the reference station 11. The signal received by the satellite 1-#3 is transmitted to the ground station antenna 2-#3.

[0089] FIG. 14 is a block diagram showing an example of a schematic configuration of a positioning device 3 according to the third embodiment. In the positioning device 3 according to the third embodiment shown in FIG. 14, a plurality of signal separation units 313 and a plurality of difference calculation units 316 are added to the positioning device 3 according to the first embodiment shown in FIG. 2, and the correlation processing unit 302 is changed to a first correlation processing unit 314 and a second correlation processing unit 315, and the orientation point calculation unit 303 is changed to an orientation point calculation unit 317.

[0090] The number of signal separators 313 provided corresponds to the number of satellites 1. Fig. 14 shows a case where three signal separators 313, 313-#1 to 313-#3, are provided as signal separators 313. The number of difference calculation units 316 provided corresponds to the number of sets of satellites 1. Fig. 14 shows a case where three difference calculation units 316, ie, difference calculation units 316-#1 to 316-#3, are provided as difference calculation units 316. 14, the first correlation processing unit 314 has first correlation processing units 314-#1 to 314-#3 corresponding to the set of satellites 1. Also, in Fig. 14, the second correlation processing unit 315 has second correlation processing units 315-#1 to 315-#3 corresponding to the set of satellites 1. Also, in Fig. 14, the orientation point calculation unit 317 has orientation point calculation units 317-#1 to 317-#3 corresponding to the set of satellites 1.

[0091] Based on the complex signal vector acquired by the corresponding signal receiving unit 301, the signal separating unit 313 separates the target signal and the signal from the reference station 11 from the complex signal vector. The target signal obtained by this signal separation unit 313 is output to a first correlation processing unit 314. In addition, the signal from the reference station 11 obtained by the signal separation unit 313 is output to a second correlation processing unit 315.

[0092] In FIG. 14, the signal separator 313-#1 separates the complex signal vector x 1(t) Based on the complex signal vector x 1(t) Then, by using filtering in the frequency domain, the target signal x tar1(t) and signal x from reference station 11 ref1(t) The target signal x obtained by this signal separator 313-#1 is separated. tar1(t) is output to the first correlation processor 314-#1 and the first correlation processor 314-#3. Also, the signal x from the reference station 11 obtained by the signal separator 313-#1 is ref1(t) are output to second correlation processing section 315-#1 and second correlation processing section 315-#3. Furthermore, the signal separation unit 313-#2 separates the complex signal vector x 2(t) Based on the complex signal vector x 2(t) Then, by using filtering in the frequency domain, the target signal x tar2(t) and signal x from reference station 11 ref2(t) The target signal x obtained by this signal separator 313-#2 is separated. tar2(t)is output to the first correlation processor 314-#1 and the first correlation processor 314-#2. Also, the signal x from the reference station 11 obtained by the signal separator 313-#2 is ref2(t) are output to second correlation processing section 315-#1 and second correlation processing section 315-#2. Furthermore, the signal separation unit 313-#3 separates the complex signal vector x 3(t) Based on the complex signal vector x 3(t) Then, by using filtering in the frequency domain, the target signal x tar3(t) and signal x from reference station 11 ref3(t) The target signal x obtained by this signal separator 313-#3 is tar3(t) is output to the first correlation processor 314-#2 and the first correlation processor 314-#3. Also, the signal x from the reference station 11 obtained by the signal separator 313-#3 is ref3(t) are output to second correlation processing section 315-#2 and second correlation processing section 315-#3.

[0093] The first correlation processing unit 314 calculates TDOA and FDOA information based on the target signals obtained by each signal separation unit 313 by correlation processing between the target signals. Specifically, the first correlation processor 314 calculates TDOA and FDOA information by extracting peak values ​​of CAF as correlation processing between the target signals according to the method described in Non-Patent Document 1. Note that if the target radio wave source 10 is a radar wave source, there will be multiple peak values ​​of CAF, and as a result, multiple pieces of TDOA and FDOA information will be calculated. The signal indicating the TDOA and FDOA information calculated by the first correlation processor 314 is output to the difference calculator 316 .

[0094] In FIG. 14, the first correlation processor 314-#1 extracts the target signal x obtained by the signal separator 313-#1. tar1(t) and the target signal x obtained by the signal separation unit 313-#2 ta r2(t) Based on this, the target signal x tar1(t) ,xtar2(t) By correlation processing between 12(i) and FDOAf 12(i) The TDOAτ calculated by the first correlation processor 314-#1 is 12(i) and FDOAf 12(i ) A signal indicating this information is output to the difference calculation unit 316-#1. The first correlation processor 314-#2 also processes the target signal x obtained by the signal separator 313-#2. tar2(t) and the target signal x obtained by the signal separation unit 313-#3 tar3( t) Based on this, the target signal x tar2(t) ,x tar3(t) By correlation processing between 23(j) and FDOAf 23(j) The TDOAτ calculated by the first correlation processor 314-#2 is 23(j) and FDOAf 23(j) A signal indicating this information is output to the difference calculation unit 316-#2. The first correlation processor 314-#3 also processes the target signal x obtained by the signal separator 313-#1. tar1(t) and the target signal x obtained by the signal separation unit 313-#3 tar3( t) Based on this, the target signal x tar1(t) ,x tar3(t) By correlation processing between 13(k) and FDOAf 13(k) The TDOAτ calculated by the first correlation processor 314-#3 is 13(k) and FDOAf 13(k) A signal indicating this information is output to the difference calculation unit 316-#3.

[0095] The second correlation processing unit 315 calculates TDOA and FDOA information based on the signals from the reference station 11 obtained by each signal separation unit 313 by correlation processing between the signals. Specifically, the second correlation processor 315 calculates TDOA and FDOA information by extracting peak values ​​of the CAF as a correlation process between the above signals according to the method described in Non-Patent Document 1. Note that if the reference station 11 is a radar wave source, multiple peaks will exist in the CAF, but since its position is known, it is possible to extract the TDOA and FDOA from the reference station 11. The signal indicating the TDOA and FDOA information calculated by the second correlation processor 315 is output to the difference calculator 316 .

[0096] In FIG. 14, the second correlation processor 315-#1 separates the signal x from the reference station 11 obtained by the signal separator 313-#1. ref1(t) and the signal x from the reference station 11 obtained by the signal separator 313-#2 ref2(t) Based on this, the signal x ref1 (t) ,x ref2(t) By correlation processing between 12r and FDOAf 12r The information of the TDOAτ calculated by the second correlation processor 315-#1 is 12 r and FDOAf 12r A signal indicating this information is output to the difference calculation unit 316-#1. The second correlation processor 315-#2 also separates the signal x from the reference station 11 obtained by the signal separator 313-#2. ref2(t) and the signal x from the reference station 11 obtained by the signal separator 313-#3 ref3(t) Based on this, the signal x ref2(t) ,x ref3(t) By correlation processing between 23r and FDOAf 23r The information of the TDOAτ calculated by the second correlation processor 315-#2 is 23r and FDOAf 23r A signal indicating this information is output to the difference calculation unit 316-#2. The second correlation processor 315-#3 also processes the signal x from the reference station 11 obtained by the signal separator 313-#1. ref1(t)and the signal x from the reference station 11 obtained by the signal separator 313-#3 ref3(t) Based on this, the signal x ref1(t) ,x ref3(t) By correlation processing between 13r and FDOAf 13r The TDOAτ calculated by the second correlation processor 315-#3 is 13r and FDOAf 13r A signal indicating this information is output to the difference calculation unit 316-#3.

[0097] The difference calculation unit 316 calculates the difference between TDOAs and the difference between FDOAs based on the information of TDOAs and FDOAs calculated by the first correlation processing unit 314 and the information of TDOAs and FDOAs calculated by the second correlation processing unit 315. A signal indicating the difference calculated by this difference calculation unit 316 is output to the corresponding orientation point calculation unit 317.

[0098] In FIG. 14, the difference calculation unit 316-#1 calculates the TDOA calculated by the first correlation processing unit 314-#1. 12(i) and TDOAτ1 calculated by the second correlation processor 315-#1 2r The difference τ 12-r(i) , and the FDOA calculated by the first correlation processor 314-#1 12(i) and FDOAf calculated by the second correlation processor 315-#1 12r The difference between f 12-r(i) The difference τ calculated by the difference calculation unit 316-#1 12-r(i) ,f 12-r(i) A signal indicating this is output to the orientation point calculation unit 317-#1. The difference calculation unit 316-#2 calculates the TDOA calculated by the first correlation processing unit 314-#2. 23(j) and the TDOAτ calculated by the second correlation processor 315-#2 23r The difference τ 23-r(j) , and the FDOA calculated by the first correlation processor 314-#2 23(j) and FDOAf calculated by the second correlation processor 315-#2 23r The difference between f23-r(j) The difference τ2 calculated by this difference calculation unit 316-#2 3-r(i) ,f 23-r(i) A signal indicating this is output to the orientation point calculation unit 317-#2. The difference calculation unit 316-#3 calculates the TDOA calculated by the first correlation processing unit 314-#3. 13(k) and the TDOAτ calculated by the second correlation processor 315-#3. 13r The difference τ 13-r(k) , and the FDOA calculated by the first correlation processor 314-#3 13(k) and FDOAf calculated by the second correlation processor 315-#3 13r The difference between f 13-r(k) The difference τ1 calculated by this difference calculation unit 316-#3 3-r(i) ,f 13-r(i) A signal indicating this is output to the orientation point calculation unit 317-#3.

[0099] The orientation point calculation unit 317 performs position orientation processing using the difference calculated by the difference calculation unit 316, thereby obtaining an orientation point corresponding to the difference. A signal indicating the orientation point calculated by the orientation point calculation unit 317 is output to the orientation point accumulation unit 304.

[0100] In FIG. 14, the orientation point calculation unit 317-#1 calculates the difference τ 12-r(i) ,f 12-r(i) By performing position location processing using 12(i) The orientation point p calculated by the orientation point calculation unit 317-#1 is calculated. 12(i) The signal indicating this is output to the orientation point storage unit 304. In addition, the orientation point calculation unit 317-#2 calculates the difference τ 23-r(j) ,f 23-r(j) By performing position location processing using 23(j) The orientation point p calculated by the orientation point calculation unit 317-#2 is calculated. 23(j) The signal indicating this is output to the orientation point storage unit 304. Further, the orientation point calculation unit 317-#3 calculates the difference τ 13-r(k) ,f 13-r(k) By performing position location processing using 13(k) The orientation point p calculated by the orientation point calculation unit 317-#3 is calculated. 13(k) The signal indicating this is output to the orientation point storage unit 304.

[0101] Next, an example of the operation of the positioning device 3 according to the third embodiment shown in FIG. 14 will be described with reference to FIG.

[0102] The processing of steps ST301 and ST307 to ST313 in the positioning device 3 according to the third embodiment shown in FIG. 15 is the same as the processing of steps ST101 and ST104 to ST110 in the positioning device 3 according to the first embodiment shown in FIG.

[0103] Then, based on the complex signal vector acquired by the corresponding signal receiving unit 301, the signal separating unit 313 separates the target signal and the signal from the reference station 11 from the complex signal vector (step ST302). The target signal obtained by this signal separation unit 313 is output to a first correlation processing unit 314. In addition, the signal from the reference station 11 obtained by the signal separation unit 313 is output to a second correlation processing unit 315.

[0104] In FIG. 14, the signal separator 313-#1 separates the complex signal vector x 1(t) Based on the complex signal vector x 1(t) Then, by using filtering in the frequency domain, the target signal x tar1(t) and signal x from reference station 11 ref1(t) The target signal x obtained by this signal separator 313-#1 is separated. tar1(t) is output to the first correlation processor 314-#1 and the first correlation processor 314-#3. Also, the signal x from the reference station 11 obtained by the signal separator 313-#1 is ref1(t)are output to second correlation processing section 315-#1 and second correlation processing section 315-#3. Furthermore, the signal separation unit 313-#2 separates the complex signal vector x 2(t) Based on the complex signal vector x 2(t) Then, by using filtering in the frequency domain, the target signal x tar2(t) and signal x from reference station 11 ref2(t) The target signal x obtained by this signal separator 313-#2 is separated. tar2(t) is output to the first correlation processor 314-#1 and the first correlation processor 314-#2. Also, the signal x from the reference station 11 obtained by the signal separator 313-#2 is ref2(t) are output to second correlation processing section 315-#1 and second correlation processing section 315-#2. Furthermore, the signal separation unit 313-#3 separates the complex signal vector x 3(t) Based on the complex signal vector x 3(t) Then, by using filtering in the frequency domain, the target signal x tar3(t) and signal x from reference station 11 ref3(t) The target signal x obtained by this signal separator 313-#3 is tar3(t) is output to the first correlation processor 314-#2 and the first correlation processor 314-#3. Also, the signal x from the reference station 11 obtained by the signal separator 313-#3 is ref3(t) are output to second correlation processing section 315-#2 and second correlation processing section 315-#3.

[0105] Next, first correlation processing section 314 calculates information on TDOA and FDOA by correlation processing between the target signals based on the target signals obtained by each signal separation section 313 (step ST303). Specifically, the first correlation processor 314 calculates TDOA and FDOA information by extracting peak values ​​of CAF as correlation processing between the target signals according to the method described in Non-Patent Document 1. Note that if the target radio wave source 10 is a radar wave source, there will be multiple peak values ​​of CAF, and as a result, multiple pieces of TDOA and FDOA information will be calculated. The signal indicating the TDOA and FDOA information calculated by the first correlation processor 314 is output to the difference calculator 316 .

[0106] In FIG. 14, the first correlation processor 314-#1 extracts the target signal x obtained by the signal separator 313-#1. tar1(t) and the target signal x obtained by the signal separation unit 313-#2 ta r2(t) Based on this, the target signal x tar1(t) ,x tar2(t) By correlation processing between 12(i) and FDOAf 12(i) The TDOAτ calculated by the first correlation processor 314-#1 is 12(i) and FDOAf 12(i ) A signal indicating this information is output to the difference calculation unit 316-#1. The first correlation processor 314-#2 also processes the target signal x obtained by the signal separator 313-#2. tar2(t) and the target signal x obtained by the signal separation unit 313-#3 tar3( t) Based on this, the target signal x tar2(t) ,x tar3(t) By correlation processing between 23(j) and FDOAf 23(j) The TDOAτ calculated by the first correlation processor 314-#2 is 23(j) and FDOAf 23(j) A signal indicating this information is output to the difference calculation unit 316-#2. The first correlation processor 314-#3 also processes the target signal x obtained by the signal separator 313-#1. tar1(t) and the target signal x obtained by the signal separation unit 313-#3 tar3( t)Based on this, the target signal x tar1(t) ,x tar3(t) By correlation processing between 13(k) and FDOAf 13(k) The TDOAτ calculated by the first correlation processor 314-#3 is 13(k) and FDOAf 13(k) A signal indicating this information is output to the difference calculation unit 316-#3.

[0107] Further, the second correlation processing unit 315 calculates information on TDOA and FDOA based on the signals from the reference station 11 obtained by each signal separation unit 313 by correlation processing between the signals (step ST304). Specifically, the second correlation processor 315 calculates TDOA and FDOA information by extracting peak values ​​of the CAF as a correlation process between the above signals according to the method described in Non-Patent Document 1. Note that if the reference station 11 is a radar wave source, multiple peaks will exist in the CAF, but since its position is known, it is possible to extract the TDOA and FDOA from the reference station 11. The signal indicating the TDOA and FDOA information calculated by the second correlation processor 315 is output to the difference calculator 316 .

[0108] In FIG. 14, the second correlation processor 315-#1 separates the signal x from the reference station 11 obtained by the signal separator 313-#1. ref1(t) and the signal x from the reference station 11 obtained by the signal separator 313-#2 ref2(t) Based on this, the signal x ref1 (t) ,x ref2(t) By correlation processing between 12r and FDOAf 12r The information of the TDOAτ calculated by the second correlation processor 315-#1 is 12 r and FDOAf 12r A signal indicating this information is output to the difference calculation unit 316-#1. The second correlation processor 315-#2 also separates the signal x from the reference station 11 obtained by the signal separator 313-#2. ref2(t) and the signal x from the reference station 11 obtained by the signal separator 313-#3 ref3(t) Based on this, the signal x ref2(t) ,x ref3(t) By correlation processing between 23r and FDOAf 23r The information of the TDOAτ calculated by the second correlation processor 315-#2 is 23r and FDOAf 23r A signal indicating this information is output to the difference calculation unit 316-#2. The second correlation processor 315-#3 also processes the signal x from the reference station 11 obtained by the signal separator 313-#1. ref1(t) and the signal x from the reference station 11 obtained by the signal separator 313-#3 ref3(t) Based on this, the signal x ref1(t) ,x ref3(t) By correlation processing between 13r and FDOAf 13r The TDOAτ calculated by the second correlation processor 315-#3 is 13r and FDOAf 13r A signal indicating this information is output to the difference calculation unit 316-#3.

[0109] Next, the difference calculation unit 316 calculates the difference between the TDOAs and the difference between the FDOAs based on the information of the TDOAs and FDOAs calculated by the first correlation processing unit 314 and the information of the TDOAs and FDOAs calculated by the second correlation processing unit 315 (step ST305). A signal indicating the difference calculated by this difference calculation unit 316 is output to the corresponding orientation point calculation unit 317.

[0110] In FIG. 14, the difference calculation unit 316-#1 calculates the TDOA calculated by the first correlation processing unit 314-#1 as shown in the following equations (37) and (40). 12(i) and the TDOAτ calculated by the second correlation processor 315-#1. 12r The difference τ 12-r(i), and the FDOA calculated by the first correlation processor 314-#1 12(i) and FDOAf calculated by the second correlation processor 315-#1 12r The difference between f 12-r(i) The difference τ calculated by the difference calculation unit 316-#1 12-r(i) ,f 12-r(i) A signal indicating this is output to the orientation point calculation unit 317-#1. Further, the difference calculation unit 316-#2 calculates the TDOA calculated by the first correlation processing unit 314-#2 as shown in the following equations (38) and (41). 23(j) and the TDOAτ calculated by the second correlation processor 315-#2 23r The difference τ 23-r(j) , and the FDOA calculated by the first correlation processor 314-#2 23(j) and FDOAf calculated by the second correlation processor 315-#2 23r The difference between f 23-r(j) The difference τ calculated by the difference calculation unit 316-#2 23-r(i) ,f 23-r(i) A signal indicating this is output to the orientation point calculation unit 317-#2. Further, the difference calculation unit 316-#3 calculates the TDOA calculated by the first correlation processing unit 314-#3 as shown in the following equations (39) and (42). 13(k) and the TDOAτ calculated by the second correlation processor 315-#3. 13r The difference τ 13-r(k) , and the FDOA calculated by the first correlation processor 314-#3 13(k) and FDOAf calculated by the second correlation processor 315-#3 13r The difference between f 13-r(k) The difference τ calculated by the difference calculation unit 316-#3 13-r(i) ,f 13-r(i) A signal indicating this is output to the orientation point calculation unit 317-#3. TIFF0007734880000009.tif66166

[0111] As described above, the positioning device 3 according to the third embodiment takes the difference between the TDOA and FDOA calculated from two types of signals received from the same satellite 1. As a result, the positioning device 3 according to the third embodiment can reduce offset errors in the TDOA and FDOA caused by the satellite 1, such as signal delays due to circuits within the satellite 1 and frequency transitions due to frequency conversion.

[0112] Next, the orientation point calculation unit 317 performs a position orientation process using the difference calculated by the difference calculation unit 316, thereby obtaining an orientation point corresponding to the difference (step ST306). A signal indicating the orientation point calculated by the orientation point calculation unit 317 is output to the orientation point accumulation unit 304.

[0113] In FIG. 14, the orientation point calculation unit 317-#1 calculates the difference τ 12-r(i) ,f 12-r(i) By performing position location processing using 12(i) Specifically, the orientation point calculation unit 317-#1 solves the simultaneous equations of the following expressions (43), (44), and (7) to calculate the orientation point p 12(i) The orientation point p calculated by the orientation point calculation unit 317-#1 is calculated. 12(i) The signal indicating this is output to the orientation point storage unit 304. In addition, the orientation point calculation unit 317-#2 calculates the difference τ 23-r(j) ,f 23-r(j) By performing position location processing using 23(j) Specifically, the orientation point calculation unit 317-#2 solves the simultaneous equations of the following expressions (45), (46), and (7) to calculate the orientation point p 23(j) The orientation point p calculated by the orientation point calculation unit 317-#2 is calculated. 23(j) The signal indicating this is output to the orientation point storage unit 304. Further, the orientation point calculation unit 317-#3 calculates the difference τ 13-r(k) ,f 13-r(k)By performing position location processing using 13(k) Specifically, the orientation point calculation unit 317-#3 calculates the orientation point p by solving the simultaneous equations of the following expressions (47), (48), and (7). 13(k) The orientation point p calculated by the orientation point calculation unit 317-#3 is calculated. 13(k) The signal indicating this is output to the orientation point storage unit 304.

[0114] In addition, in equations (43) to (48), f r0 indicates the center frequency of reference station 11, and p r indicates the position of the reference station 11. TIFF0007734880000010.tif137166

[0115] From equations (43), (44), and (7), the control point p 12(i) Then, from equations (45), (46), and (7), the orientation point p 23(j) Then, from equations (47), (48), and (7), the orientation point p 13(k) is calculated, the offset error originating from the satellite 1 is reduced more than when the control point calculation unit 303 in the first embodiment is used. Therefore, in the positioning device 3 according to the third embodiment, it is possible to estimate the position of the target radio wave source 10 with higher accuracy in the subsequent processing compared to the first embodiment.

[0116] In this way, the positioning device 3 according to the third embodiment uses a signal from the reference station 11 whose position is known. As a result, the positioning device 3 according to the third embodiment can reduce offset errors related to the TDOA and FDOA originating from the satellite 1, and can estimate the position of the target radio wave source 10 with higher accuracy compared to when the signal from the reference station 11 is not used.

[0117] As described above, according to the third embodiment, the positioning device 3 includes a plurality of signal receiving units 301 provided for each of a plurality of satellites 1, each of which acquires a complex signal vector of a signal received by the satellite 1; a signal separating unit 313 provided for each of the signal receiving units 301, which separates a target signal and a signal from a reference station 11 from the complex signal vector acquired by the signal receiving unit 301, a first correlation processing unit 314 which calculates information on TDOA and FDOA by correlation processing between the target signals based on the target signals acquired by the signal separating unit 313; a second correlation processing unit 315 which calculates information on TDOA and FDOA by correlation processing between the signals based on the signals from the reference station 11 acquired by the signal separating unit 313; The positioning device 3 according to the third embodiment includes a difference calculation unit 316 that calculates a difference between the TDOAs and a difference between the FDOAs based on the information of the TDOA and FDOA calculated by the second correlation processing unit 315, a control point calculation unit 317 that calculates a control point corresponding to the difference based on the difference calculated by the difference calculation unit 316, a coordinate conversion unit 306 that converts the control point into latitude and longitude information based on the control points for a plurality of times calculated by the control point calculation unit 317, a frequency distribution calculation unit 307 that calculates a frequency distribution of the control points based on the latitude and longitude information obtained by the coordinate conversion unit 306, a control point extraction unit 308 that extracts control points included in an area with the maximum frequency from the frequency distribution calculated by the frequency distribution calculation unit 307, and a position estimation unit that estimates the position of the target radio wave source 10 based on the control point extracted by the control point extraction unit 308. As a result, the positioning device 3 according to the third embodiment can estimate the position of the target radio wave source 10 with higher accuracy in addition to the effects of the first embodiment.

[0118] Finally, with reference to FIG. 16, an example of the hardware configuration of the positioning device 3 according to the first to third embodiments will be described.

[0119] 16, the hardware configuration example of the positioning device 3 according to the first embodiment is configured with a signal receiving unit 301 and a signal processing device 31. The signal processing device 31 includes a processor 32, a memory 33, an input interface 34, an output interface 35, and a signal path 36.

[0120] Of the components of the positioning device 3 according to the first embodiment, the correlation processing unit 302, the control point calculation unit 303, the control point accumulation unit 304, the accumulation time determination unit 305, the coordinate conversion unit 306, the frequency distribution calculation unit 307, the control point extraction unit 308, the error ellipse calculation unit 309, the common part calculation unit 310, and the centroid calculation unit 311 may be realized by a processor 32 consisting of an LSI (Large Scale Integrated circuit) such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array), for example. Alternatively, the correlation processing unit 302, the orientation point calculation unit 303, the orientation point accumulation unit 304, the accumulation time determination unit 305, the coordinate conversion unit 306, the frequency distribution calculation unit 307, the orientation point extraction unit 308, the error ellipse calculation unit 309, the common part calculation unit 310, and the centroid calculation unit 311 may be implemented by a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit) that executes a computer program. The system may be implemented with one or more processors 32 including a processor processor (CPU) or processors (CPUs).

[0121] The memory 33 includes, for example, a program memory that stores various programs for realizing the signal processing function of the positioning device 3 according to the first embodiment, a work memory that is used when the processor 32 executes signal processing, and a memory into which data used in the signal processing is expanded. The memory 33 may be a plurality of semiconductor memories such as a ROM (Read Only Memory) and an SDRAM (Synchronous Dynamic Random Access Memory).

[0122] 16 is configured using a single processor 32, but is not limited to this. The signal processing function of the positioning device 3 may be realized using a plurality of processors 32 that operate in cooperation with each other. Any of the correlation processing unit 302, orientation point calculation unit 303, orientation point accumulation unit 304, accumulation time determination unit 305, coordinate conversion unit 306, frequency distribution calculation unit 307, orientation point extraction unit 308, error ellipse calculation unit 309, common part calculation unit 310, and centroid calculation unit 311 may be configured using dedicated hardware.

[0123] 16, a hardware configuration example of the positioning device 3 according to the second embodiment is configured with a signal receiving unit 301 and a signal processing device 31. The signal processing device 31 includes a processor 32, a memory 33, an input interface 34, an output interface 35, and a signal path 36.

[0124] Of the components of the positioning device 3 according to the second embodiment, the control point extraction unit 312 may be realized by a processor 32 made up of an LSI such as an ASIC or an FPGA. Alternatively, the control point extraction unit 312 may be realized by one or more processors 32 including a CPU or GPU that executes a computer program.

[0125] The memory 33 includes, for example, a program memory that stores various programs for realizing the signal processing function of the positioning device 3 according to the second embodiment, a work memory that is used when the processor 32 executes signal processing, and a memory into which data used in the signal processing is expanded. The memory 33 may be a plurality of semiconductor memories such as a ROM and an SDRAM.

[0126] 16, the configuration is not limited to a single processor 32. The signal processing function of the positioning device 3 may be realized by using a plurality of processors 32 that operate in cooperation with each other. The control point extraction unit 312 may be configured by dedicated hardware.

[0127] The configuration of the positioning device 3 according to the second embodiment is the same as that of the positioning device 3 according to the first embodiment, except for the control point extraction unit 312.

[0128] 16, a hardware configuration example of the positioning device 3 according to the third embodiment is configured with a signal receiving unit 301 and a signal processing device 31. The signal processing device 31 includes a processor 32, a memory 33, an input interface 34, an output interface 35, and a signal path 36.

[0129] Of the components of the positioning device 3 according to the second embodiment, the signal separation unit 313, the first correlation processing unit 314, the second correlation processing unit 315, the difference calculation unit 316, and the orientation point calculation unit 317 may be realized by a processor 32 made up of an LSI such as an ASIC or an FPGA. Alternatively, the signal separation unit 313, the first correlation processing unit 314, the second correlation processing unit 315, the difference calculation unit 316, and the orientation point calculation unit 317 may be realized by one or more processors 32 including a CPU or GPU that executes a computer program.

[0130] The memory 33 includes, for example, a program memory that stores various programs for implementing the signal processing functions of the positioning device 3 according to the third embodiment, a work memory that is used when the processor 32 executes signal processing, and a memory into which data used in the signal processing is expanded. The memory 33 may be a plurality of semiconductor memories such as a ROM and an SDRAM.

[0131] 16, the configuration is not limited to a single processor 32. The signal processing function of the positioning device 3 may be realized using a plurality of processors 32 that operate in cooperation with each other. Any of the signal separation unit 313, the first correlation processing unit 314, the second correlation processing unit 315, the difference calculation unit 316, and the orientation point calculation unit 317 may be configured as dedicated hardware.

[0132] In addition, the configuration of the positioning device 3 according to embodiment 3 is the same as that of the positioning device 3 according to embodiment 1, except for the signal separation unit 313, the first correlation processing unit 314, the second correlation processing unit 315, the difference calculation unit 316, and the orientation point calculation unit 317.

[0133] It should be noted that the embodiments may be freely combined, or any of the components in each embodiment may be modified, or any of the components in each embodiment may be omitted. [Industrial Applicability]

[0134] The positioning device according to the present disclosure is capable of locating an unknown target radio wave source without using directional information, regardless of the type of the target radio wave source, and is suitable for use in positioning devices that locate unknown target radio wave sources. [Explanation of symbols]

[0135] 1 satellite, 2 ground station antenna, 3 positioning device, 10 target radio wave source, 11 reference station, 31 signal processing device, 32 processor, 33 memory, 34 input interface, 35 output interface, 36 signal path, 301 signal receiving unit, 302 correlation processing unit, 303 control point calculation unit, 304 control point storage unit, 305 storage time determination unit, 306 coordinate conversion unit, 307 frequency distribution calculation unit, 308 control point extraction unit, 309 error ellipse calculation unit, 310 common part calculation unit, 311 centroid calculation unit, 312 control point extraction unit, 313 signal separation unit, 314 first correlation processing unit, 315 second correlation processing unit, 316 difference calculation unit, 317 control point calculation unit.

Claims

1. A plurality of signal receiving units provided for each of a plurality of satellites, each of which acquires a complex signal vector of a signal received by the corresponding satellite; a correlation processing unit that calculates information on TDOA and FDOA by correlation processing between the complex signal vectors based on the complex signal vectors acquired by the signal receiving unit; a control point calculation unit that calculates a control point corresponding to the TDOA and FDOA based on the information of the TDOA and FDOA calculated by the correlation processing unit; a coordinate conversion unit that converts the control points into latitude and longitude information based on the control points for multiple times calculated by the control point calculation unit; a frequency distribution calculation unit that calculates a frequency distribution of the control points based on the latitude and longitude information obtained by the coordinate conversion unit; a control point extraction unit that extracts a control point included in an area with the maximum frequency from the frequency distribution calculated by the frequency distribution calculation unit, a position estimation unit that estimates a position of a target radio wave source based on the control points extracted by the control point extraction unit, The position estimation unit an error ellipse calculation unit that calculates, for each pair of satellites, an error ellipse that is an area where the orientation point may exist, based on the orientation point extracted by the orientation point extraction unit; a common part calculation unit that extracts orientation points that exist in a common part of the error ellipses based on the error ellipses calculated by the error ellipse calculation unit; a center of gravity calculation unit that calculates the center of gravity of the orientation point as the position of the target radio wave source based on the orientation point extracted by the common part calculation unit; A positioning device characterized by:

2. A plurality of signal receiving units provided for each of a plurality of satellites, each of which acquires a complex signal vector of a signal received by the corresponding satellite; a correlation processing unit that calculates information on TDOA and FDOA by correlation processing between the complex signal vectors based on the complex signal vectors acquired by the signal receiving unit; a control point calculation unit that calculates a control point corresponding to the TDOA and FDOA based on the information of the TDOA and FDOA calculated by the correlation processing unit; a coordinate conversion unit that converts the control points into latitude and longitude information based on the control points for multiple times calculated by the control point calculation unit; a frequency distribution calculation unit that calculates a frequency distribution of the control points based on the latitude and longitude information obtained by the coordinate conversion unit; a control point extraction unit that calculates the number of areas in which the frequency is equal to or greater than a threshold value from the frequency distribution based on the frequency distribution calculated by the frequency distribution calculation unit, and extracts control points included in the areas; a position estimation unit that estimates a position of a target radio wave source based on the control points extracted by the control point extraction unit, The position estimation unit a plurality of error ellipse calculation units that operate in parallel in the same number as the number calculated by the control point extraction unit, and calculate an error ellipse, which is an area where the control point may exist, for each pair of satellites based on the control points extracted by the control point extraction unit; a plurality of common part calculation units, the number of which is calculated by the control point extraction unit, that operate in parallel and extract control points that exist in common parts of the error ellipses based on the error ellipses calculated by the error ellipse calculation unit; a plurality of center of gravity calculation units that operate in parallel in the number calculated by the control point extraction unit and that set the center of gravity of the control point as the position of the target radio wave source based on the control point extracted by the common part calculation unit; A positioning device characterized by:

3. A plurality of signal receiving units provided for each of a plurality of satellites, each of which acquires a complex signal vector of a signal received by the corresponding satellite; a signal separation unit provided for each of the signal receiving units, which separates a target signal and a signal from a reference station from the complex signal vector based on the complex signal vector acquired by the signal receiving unit; a first correlation processing unit that calculates information on TDOA and FDOA by correlation processing between the target signals obtained by the signal separation unit; a second correlation processing unit that calculates TDOA and FDOA information by correlation processing between the signals from the reference station obtained by the signal separation unit; a difference calculation unit that calculates a difference between TDOAs and a difference between FDOAs based on the information on the TDOAs and FDOAs calculated by the first correlation processing unit and the information on the TDOAs and FDOAs calculated by the second correlation processing unit; a orientation point calculation unit that calculates an orientation point corresponding to the difference based on the difference calculated by the difference calculation unit; a coordinate conversion unit that converts the control points into latitude and longitude information based on the control points for multiple times calculated by the control point calculation unit; a frequency distribution calculation unit that calculates a frequency distribution of the control points based on the latitude and longitude information obtained by the coordinate conversion unit; a control point extraction unit that extracts a control point included in an area with the maximum frequency from the frequency distribution calculated by the frequency distribution calculation unit, a position estimation unit that estimates a position of a target radio wave source based on the control points extracted by the control point extraction unit, The position estimation unit an error ellipse calculation unit that calculates, for each pair of satellites, an error ellipse that is an area where the orientation point may exist, based on the orientation point extracted by the orientation point extraction unit; a common part calculation unit that extracts orientation points that exist in a common part of the error ellipses based on the error ellipses calculated by the error ellipse calculation unit; a center of gravity calculation unit that calculates the center of gravity of the orientation point as the position of the target radio wave source based on the orientation point extracted by the common part calculation unit; A positioning device characterized by:

4. a signal receiving unit provided for each of a plurality of satellites, and a plurality of steps for acquiring complex signal vectors of signals received by the satellites; a correlation processing unit calculating information on TDOA and FDOA by correlation processing between the complex signal vectors based on the complex signal vectors acquired by the signal receiving unit; A step in which a control point calculation unit calculates a control point corresponding to the TDOA and FDOA based on the information of the TDOA and FDOA calculated by the correlation processing unit; a step of converting the control points into latitude and longitude information by a coordinate conversion unit based on the control points for a plurality of times calculated by the control point calculation unit; a frequency distribution calculation unit calculating a frequency distribution of the control points based on the latitude and longitude information obtained by the coordinate conversion unit; A step in which a control point extraction unit extracts control points included in an area with the maximum frequency from the frequency distribution calculated by the frequency distribution calculation unit, a step in which a position estimation unit estimates a position of a target radio wave source based on the control points extracted by the control point extraction unit, The position estimation unit an error ellipse calculation unit that calculates, for each pair of satellites, an error ellipse that is an area where the orientation point may exist, based on the orientation point extracted by the orientation point extraction unit; a common part calculation unit that extracts orientation points that exist in a common part of the error ellipses based on the error ellipses calculated by the error ellipse calculation unit; a center of gravity calculation unit that calculates the center of gravity of the orientation point as the position of the target radio wave source based on the orientation point extracted by the common part calculation unit; A positioning method characterized by:

5. a signal receiving unit provided for each of a plurality of satellites, and a plurality of steps for acquiring complex signal vectors of signals received by the satellites; a correlation processing unit calculating information on TDOA and FDOA by correlation processing between the complex signal vectors based on the complex signal vectors acquired by the signal receiving unit; A step in which a control point calculation unit calculates a control point corresponding to the TDOA and FDOA based on the information of the TDOA and FDOA calculated by the correlation processing unit; a step of converting the control points into latitude and longitude information by a coordinate conversion unit based on the control points for a plurality of times calculated by the control point calculation unit; a frequency distribution calculation unit calculating a frequency distribution of the control points based on the latitude and longitude information obtained by the coordinate conversion unit; a step in which a control point extraction unit calculates the number of areas in which the frequency is equal to or greater than a threshold from the frequency distribution based on the frequency distribution calculated by the frequency distribution calculation unit, and extracts control points included in the areas; a step in which a position estimation unit estimates a position of a target radio wave source based on the control points extracted by the control point extraction unit, The position estimation unit a plurality of error ellipse calculation units that operate in parallel in the same number as the number calculated by the control point extraction unit, and calculate an error ellipse, which is an area where the control point may exist, for each pair of satellites based on the control points extracted by the control point extraction unit; a plurality of common part calculation units, the number of which is calculated by the control point extraction unit, that operate in parallel and extract control points that exist in common parts of the error ellipses based on the error ellipses calculated by the error ellipse calculation unit; a plurality of center of gravity calculation units that operate in parallel in the number calculated by the control point extraction unit and that set the center of gravity of the control point as the position of the target radio wave source based on the control point extracted by the common part calculation unit; A positioning method characterized by:

6. a signal receiving unit provided for each of a plurality of satellites, and a plurality of steps for acquiring complex signal vectors of signals received by the satellites; a signal separation unit provided for each of the signal receiving units, which separates a target signal and a signal from a reference station from the complex signal vector based on the complex signal vector acquired by the signal receiving unit; a first correlation processing unit calculating information on TDOA and FDOA by correlation processing between the target signals based on the target signals obtained by the signal separation unit; a second correlation processing unit calculating information on TDOA and FDOA by correlation processing between the signals from the reference station obtained by the signal separation unit; a difference calculation unit calculating a difference between TDOAs and a difference between FDOAs based on the information of the TDOA and FDOA calculated by the first correlation processing unit and the information of the TDOA and FDOA calculated by the second correlation processing unit; A step in which a direction control point calculation unit calculates a direction control point corresponding to the difference based on the difference calculated by the difference calculation unit; a step of converting the control points into latitude and longitude information by a coordinate conversion unit based on the control points for a plurality of times calculated by the control point calculation unit; a frequency distribution calculation unit calculating a frequency distribution of the control points based on the latitude and longitude information obtained by the coordinate conversion unit; A step in which a control point extraction unit extracts control points included in an area with the maximum frequency from the frequency distribution calculated by the frequency distribution calculation unit, a step in which a position estimation unit estimates a position of a target radio wave source based on the control points extracted by the control point extraction unit, The position estimation unit an error ellipse calculation unit that calculates, for each pair of satellites, an error ellipse that is an area where the orientation point may exist, based on the orientation point extracted by the orientation point extraction unit; a common part calculation unit that extracts orientation points that exist in a common part of the error ellipses based on the error ellipses calculated by the error ellipse calculation unit; a center of gravity calculation unit that calculates the center of gravity of the orientation point as the position of the target radio wave source based on the orientation point extracted by the common part calculation unit; A positioning method characterized by:

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