Interferometer direction finding method and system

Abstract

The invention relates to the technical field of interferometer direction finding, and discloses an interferometer direction finding method and system, and the method comprises the steps: calculating the phase difference of a longest baseline in an antenna array through a virtual baseline method, and solving the phase difference of the longest baseline to obtain sin [alpha] corresponding to an incident angle [alpha] of an electromagnetic wave signal; calculating the actual phase difference of each real base line in the antenna array through a staggered base line method, and then solving according to the actual phase difference of each real base line to obtain a sin beta array corresponding to the incident angle beta of the electromagnetic wave signal; and subtracting the sin alpha from all the sin beta elements in the sin beta array to obtain an error array, finding a minimum error through an index, and solving according to the sin beta element corresponding to the minimum error to obtain an incident angle beta of the electromagnetic wave signal. The direction finding sensitivity and precision are high, the speed is high, and the method is suitable for a close-range direction finding scene with a high precision requirement.

Description

Technical Field

[0001] The present invention relates to the technical field of interferometer direction finding, and in particular to an interferometer direction finding method and system. Background Art

[0002] Nowadays, electromagnetic technology is developing rapidly. In daily life, electromagnetic technology is everywhere, such as communication electromagnetic waves, electromagnetic receivers, electromagnetic interference, etc., which makes it possible to discover target radiation sources and study direction-finding and positioning systems in complex electromagnetic environments. At present, conventional interferometer direction-finding methods are mainly based on the long and short baseline method, the virtual baseline method or the staggered baseline method, and the direction-finding of the target radiation source is carried out through continuous iteration. The virtual baseline method in interferometer direction-finding has a simple structure and does not have high requirements for baseline arrangement. Under noisy conditions, the result error is large, but there will be no calculation errors. And the staggered baseline method in interferometer direction-finding has strict requirements on baseline arrangement and high requirements on antenna installation accuracy. Under noisy conditions, the result error is small, but it may cause calculation errors. In addition, in complex environmental scenarios, the target radiation source transmits signals for a short time, and there is often a situation where there is no time iteration, and the angle of the target relative to the platform cannot be measured quickly and accurately.

[0003] Therefore, there is an urgent need for an interferometer direction finding method and system to solve the above problems. Summary of the invention

[0004] Based on the above, the purpose of the present invention is to provide an interferometer direction finding method and system, which has high direction finding sensitivity and accuracy and fast speed, and is suitable for short-range positioning scenarios with high precision requirements.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] An interferometer direction finding method comprises the following steps:

[0007] The phase difference of the longest baseline in the antenna array is calculated by a virtual baseline method, and then sinα corresponding to the incident angle α of the electromagnetic wave signal is obtained according to the phase difference of the longest baseline;

[0008] Calculating the actual phase difference of each real baseline in the antenna array by using the staggered baseline method, and then solving the sinβ array corresponding to the incident angle β of the electromagnetic wave signal according to the actual phase difference of each real baseline;

[0009] Subtract sinα from all sinβ elements in the sinβ array to obtain an error array, find the minimum error through the index, and solve the incident angle β of the electromagnetic wave signal according to the sinβ element corresponding to the minimum error.

[0010] As a preferred solution of the interferometer direction finding method, the method further comprises the steps of:

[0011] Performing N direction finding on the electromagnetic wave signal, calculating the incident angle α and the incident angle β by using the virtual baseline method and the staggered baseline method respectively in each direction finding;

[0012] The incident angle α and the incident angle β obtained by N calculations are subjected to fusion filtering to obtain the incident angle γ of the corrected electromagnetic wave signal, wherein the fusion filtering is calculated according to the following formula:

[0013]

[0014] Wherein, N is the number of direction finding times, N≥1; λ is the filter coefficient, which is obtained through expert experience.

[0015] As a preferred solution of an interferometer direction finding method, calculating the actual phase difference of each real baseline in the antenna array by a staggered baseline method includes the following steps:

[0016] Assume that the actual phase difference of the electromagnetic wave signal reaching a real baseline is:

[0017]

[0018] in, is the actual phase difference corresponding to the nth real baseline; τ is the incident wavelength of the electromagnetic wave signal; d n is the length corresponding to the nth real baseline; is the measured phase difference corresponding to the nth real baseline; k n is the fuzzy number corresponding to the nth real baseline; n is a positive integer greater than or equal to 1;

[0019] From formula (3), we can see that yes Remainders about 2π;

[0020] Combining equation (2) and equation (3), we get:

[0021]

[0022] set up where m1, m2, ..., m n Coprime, then m1d1=m2d2=…=m n d n ,have

[0023]

[0024] From the above formula, we can set After rounding, it is modulo m n The remainder of

[0025] According to the remainder theorem, we can solve for X, then

[0026]

[0027] The actual phase difference of the electromagnetic wave signal reaching each real baseline is obtained by calculating the fuzzy number corresponding to each real baseline.

[0028] As a preferred solution of an interferometer direction finding method, jitter is taken into account when calculating the actual phase difference of each real baseline in the antenna array by the staggered baseline method. Assuming that the maximum error of the jitter is Δε, the residue combination of the measured phase difference corresponding to each real baseline is:

[0029]

[0030] Substituting equation (8) into equation (6), we get k nleft , k n , k nright

[0031] According to the obtained fuzzy numbers corresponding to each real baseline and the left and right error values ​​of each fuzzy number, the actual phase difference of the electromagnetic wave signal reaching each real baseline and the actual phase difference left error value and the actual phase difference right error value corresponding to each actual phase difference are calculated, and the n real baselines corresponding to the n real baselines are obtained. 3 actual phase difference combinations, each of the actual phase difference combinations includes n first phase differences corresponding to n real baselines, wherein each of the first phase differences is an actual phase difference, an actual phase difference left error value, or an actual phase difference right error value.

[0032] As a preferred solution of an interferometer direction finding method, n real baselines corresponding to n are obtained by the staggered baseline method. 3 The actual phase difference combination also includes:

[0033] Taking the length of each real baseline as the X-axis and the first phase difference in each actual phase difference combination as the Y-axis, performing least squares fitting to obtain a linear relationship between each real baseline and the first phase difference in each actual phase difference combination;

[0034] Recalculate the second phase difference in each actual phase difference combination corresponding to each real baseline according to the linear relationship;

[0035] Each sinβ corresponding to the incident angle β of the electromagnetic wave signal is obtained by solving each second phase difference obtained by the recalculation, and is saved as a sinβ array. The sinβ array includes n 3 sinβ elements.

[0036] An interferometer direction finding system, comprising:

[0037] A first calculation module is used to calculate the phase difference of the longest baseline in the antenna array by a virtual baseline method, and then solve sinα corresponding to the incident angle α of the electromagnetic wave signal according to the phase difference of the longest baseline;

[0038] A second calculation module is used to calculate the actual phase difference of each real baseline in the antenna array by using a staggered baseline method, and then solve the sinβ array corresponding to the incident angle β of the electromagnetic wave signal according to the actual phase difference of each real baseline;

[0039] The third calculation module is used to subtract sinα from all sinβ elements in the sinβ array to obtain an error array, find the minimum error through indexing, and solve the incident angle β of the electromagnetic wave signal according to the sinβ element corresponding to the minimum error.

[0040] As a preferred solution of an interferometer direction finding system, it also includes:

[0041] The fusion filter calculation module is used to perform fusion filtering on the incident angle α and the incident angle β obtained by N times of calculation, and calculate the incident angle γ of the corrected electromagnetic wave signal.

[0042] The beneficial effects of the present invention are:

[0043] The present invention provides an interferometer direction finding method, which obtains sinα corresponding to the incident angle α of an electromagnetic wave signal by a virtual baseline method, then obtains the sinβ array corresponding to the incident angle β of the electromagnetic wave signal by a staggered baseline method, and finally finds the sinβ closest to sinα by indexing, and obtains the incident angle β of the electromagnetic wave signal according to the found sinβ. The incident angle of the electromagnetic wave signal obtained by the interferometer direction finding method is more accurate and faster, and can provide real-time and effective target orientation for subsequent precise positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0045] Figure 1 The process of the interferometer direction finding method provided by the embodiment of the present invention is Figure 1 ;

[0046] Figure 2 The process of the interferometer direction finding method provided by the embodiment of the present invention is Figure 2 ;

[0047] Figure 3 is an antenna array distribution diagram provided by an embodiment of the present invention;

[0048] Figure 4 It is a schematic diagram of the structure of an antenna array provided by an embodiment of the present invention loaded on a flying vehicle.

[0049] In the figure:

[0050] 1. Flying carrier. DETAILED DESCRIPTION

[0051] The present invention will be further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention.

[0052] like Figure 1 and Figure 2 As shown, this embodiment provides an interferometer direction finding method, and its main application scenario is electromagnetic radiation source direction finding based on an electromagnetic sensing platform. When the target is a signal radiation source, the interferometer direction finding method can well measure the direction angle or heading angle of the target radiation source relative to the loading platform, thereby helping the positioning system to determine the specific range for the final target positioning. Specifically, the interferometer direction finding method includes the following steps:

[0053] S1: Calculate the phase difference of the longest baseline in the antenna array by the virtual baseline method, and then solve the sinα corresponding to the incident angle α of the electromagnetic wave signal according to the phase difference of the longest baseline;

[0054] S2: Calculate the actual phase difference of each real baseline in the antenna array by using the staggered baseline method, and then solve the sinβ array corresponding to the incident angle β of the electromagnetic wave signal according to the actual phase difference of each real baseline;

[0055] S3: Subtract sinα from all sinβ elements in the sinβ array to obtain an error array, and find the minimum error through the index. The incident angle β of the electromagnetic wave signal is obtained by solving the sinβ element corresponding to the minimum error.

[0056] The sinα corresponding to the incident angle α of the electromagnetic wave signal is obtained by the virtual baseline method, and then the sinβ array corresponding to the incident angle β of the electromagnetic wave signal is obtained by the staggered baseline method. Finally, the sinβ closest to sinα can be found by indexing, and the incident angle β of the electromagnetic wave signal can be obtained according to the found sinβ. The incident angle of the electromagnetic wave signal obtained by the interferometer direction finding method is more accurate and faster, and can provide real-time and effective target orientation for subsequent close-range positioning.

[0057] More specifically, in step S1, the following steps are specifically included:

[0058] S11: several virtual baselines are set in the real baseline array so that the shortest virtual baseline length is less than half the wavelength of the highest frequency of the broadband signal; wherein, the setting of the virtual baseline is a relatively mature prior art, and therefore, it will not be described in detail here. The lengths of the real baselines and virtual baselines are known, and are set to be D1, D2, ..., D n .

[0059] S12: Due to:

[0060]

[0061] The phase difference of the shortest virtual baseline is obtained according to the following formula:

[0062]

[0063] in, is the phase difference of the shortest virtual baseline, The corresponding measured phase difference of the shortest virtual baseline;

[0064] S13: Obtaining the phase difference of the second shortest baseline according to the phase difference of the shortest virtual baseline; specifically comprising the following steps:

[0065] The rough value of the phase difference of the second shortest baseline is calculated by the following formula:

[0066]

[0067] because

[0068]

[0069] in, is the phase difference of the second shortest baseline, The corresponding measured phase difference of the second shortest baseline;

[0070] Find the index with The closest The corresponding k 2虚 , the exact value of the phase difference of the second shortest baseline can be obtained.

[0071] S14: Calculate the phase difference of the third shortest baseline according to the phase difference of the second shortest baseline, and so on to calculate the phase difference of the longest baseline.

[0072] S15: Substitute the phase difference of the longest baseline into equation (101) to obtain sinα corresponding to the incident angle α of the electromagnetic wave signal.

[0073] More specifically, calculating the actual phase difference of each real baseline in the antenna array by the staggered baseline method includes the following steps:

[0074] S21: Assume that the actual phase difference of the electromagnetic wave signal reaching a real baseline is:

[0075]

[0076] in, is the actual phase difference corresponding to the nth real baseline; τ is the incident wavelength of the electromagnetic wave signal; d n is the length corresponding to the nth real baseline; is the measured phase difference corresponding to the nth real baseline; k n is the fuzzy number corresponding to the nth real baseline; n is a positive integer greater than or equal to 1, for example, n is 1, 2, 3, etc.

[0077] From formula (3), we can see that yes Remainders about 2π;

[0078] Combining equation (2) and equation (3), we get:

[0079]

[0080] set up where m1, m2, ..., m n Coprime, then m1d1=m2d2=…=m n d n , wherein the layout positions of several antennas are determined according to the effective layout length of the missile body, namely d1, d2, ..., d n are known quantities, namely n1, m2, ..., m n Known, for example, m1:m2:…:m n =1:2:3:…:n, or m1:m2:…:m n =3:5:7:…:n, etc.

[0081]

[0082] From the above formula, we can set After rounding, it is modulo m n The remainder of

[0083] According to the remainder theorem, we can solve for X, then

[0084]

[0085] The actual phase difference of the electromagnetic wave signal reaching each real baseline is calculated based on the fuzzy number corresponding to each real baseline.

[0086] Preferably, jitter is taken into account when calculating the actual phase difference of each real baseline in the antenna array by the staggered baseline method. Assuming that the maximum error of the jitter is Δε, the residue combination of the measured phase difference corresponding to each real baseline is:

[0087]

[0088] Substituting equation (8) into equation (6), we get k nleft , k n , k nright

[0089] According to the fuzzy numbers corresponding to each real baseline and the left and right error values ​​of each fuzzy number, the actual phase difference of the electromagnetic wave signal reaching each real baseline and the actual phase difference left error value and the actual phase difference left error value corresponding to each actual phase difference are calculated, and the n real baselines corresponding to n real baselines are obtained. 3 actual phase difference combinations, each actual phase difference combination includes n first phase differences corresponding to n real baselines, wherein each first phase difference is an actual phase difference, an actual phase difference left error value, or an actual phase difference right error value.

[0090] S22: Obtain n real baselines corresponding to n 3 The actual phase difference combination also includes:

[0091] The length of each real baseline is taken as the X-axis, and the first phase difference in each actual phase difference combination is taken as the Y-axis, and the least squares fitting is performed to obtain the linear relationship between each real baseline and the first phase difference in each actual phase difference combination;

[0092] Recalculate the second phase difference in each actual phase difference combination corresponding to each real baseline according to the linear relationship;

[0093] According to each second phase difference obtained by recalculation, each sinβ corresponding to the incident angle β of the electromagnetic wave signal is solved and saved as a sinβ array. The sinβ array includes n 3 sinβ elements.

[0094] More specifically, after obtaining the sinβ array, step S3 is performed. In this embodiment, n 3 Subtract sinα from each sinβ element to get the error array, then find the minimum error through the index, and determine the sinβ[Index] closest to sinα based on the minimum error. Then, the incident angle β of the electromagnetic wave signal can be solved based on sinβ[Index].

[0095] In order to further improve the accuracy of the incident angle of the electromagnetic wave signal, the interferometer direction finding method provided in this embodiment further includes the following steps:

[0096] S41: performing N direction finding on the electromagnetic wave signal, and calculating the incident angle α and the incident angle β by using the virtual baseline method and the staggered baseline method respectively for each direction finding;

[0097] S42: Perform fusion filtering on the incident angle α and the incident angle β obtained by N calculations to obtain the incident angle γ of the corrected electromagnetic wave signal, wherein the fusion filtering is calculated according to the following formula:

[0098]

[0099] Wherein, N is the number of direction finding times, N≥1; λ is the filter coefficient, which is obtained through expert experience.

[0100] The interferometer direction finding method provided by this embodiment can effectively solve the technical problems of limited accuracy and fuzzy direction finding in the prior art, integrate the advantages of the virtual baseline method and the staggered baseline method, learn from each other's strengths and overcome their weaknesses, increase the anti-interference performance under noise conditions, and achieve high sensitivity, high accuracy and high speed in direction finding. It provides real-time and effective target orientation for close-range positioning, and can be used in application scenarios such as target positioning and effective signal direction finding.

[0101] The present invention will be further described below with reference to the embodiments:

[0102] like Figure 3 and Figure 4 As shown in the figure, based on the conventional measurement frequency range and the size of the loaded antenna, four real direction-finding antennas are arranged within the effective arrangement length of the missile body, namely E, F, G, and H, and two virtual antennas are set, namely A and B, where the length of each baseline is D BF , D AF , D EF , D EG , D EH .

[0103] According to steps S1-S4, the phase difference of each baseline is solved in turn by the virtual baseline method. Thus, according to the phase difference corresponding to the longest baseline Obtain sinα corresponding to the incident angle α of the electromagnetic wave signal.

[0104] When the actual phase difference of each real baseline in the antenna array is calculated by the staggered baseline method, d1 = D EF d2=D EG d3=D EH ;

[0105] According to step S2, the fuzzy number corresponding to each real baseline is obtained, and the actual phase difference of the electromagnetic wave signal reaching each real baseline is calculated. If jitter is taken into account, the error value of each actual phase difference is calculated Then, 27 actual phase difference combinations corresponding to each real baseline can be obtained:

[0106] Take d1, d2, and d3 as the X-axis, and the above 27 actual phase difference combinations as the Y-axis, respectively, and perform least squares fitting to obtain the linear relationship between each real baseline and the first phase difference in each corresponding actual phase difference combination; recalculate the second phase difference in each actual phase difference combination corresponding to each real baseline according to the linear relationship;

[0107] Then, 27 sinβs are obtained according to the re-determined second phase difference in each actual phase difference combination, and the 27 sinβs are saved as a sinβ array;

[0108] Subtract sinα from each sinβ element in the sinβ array to obtain an error array, then find the sinβ element corresponding to the minimum error through the index, and calculate the incident angle β of the electromagnetic wave signal based on the sinβ element closest to sinα.

[0109] Perform direction finding N times, that is, repeat the above steps, and finally perform fusion filtering on the incident angle α and the incident angle β obtained by N times calculation according to step S42 to obtain the incident angle γ of the corrected electromagnetic wave signal.

[0110] like Figure 4 As shown, this embodiment also provides an interferometer direction-finding system that can be loaded on a flying vehicle 1. The interferometer direction-finding system includes an antenna array and an intelligent electromagnetic sensing system. The intelligent sensing system can be used to process the input signal of the antenna array and obtain the phase difference of each baseline. The antenna array is installed at the bottom or both sides of the flying vehicle 1. Each antenna channel in the antenna array will receive electromagnetic wave signals in real time and transmit them to the intelligent electromagnetic sensing system to perform direction-finding of the target radiation source. When a target radiation source emits electromagnetic waves, the intelligent electromagnetic sensing system will receive the electromagnetic waves through the antenna array and perform spectrum analysis to obtain the signal wavelength; then the signal cross-correlation algorithm is used to obtain the phase difference of each baseline. Specifically, the intelligent electromagnetic perception system includes a first calculation module, a second calculation module and a third calculation module. The first calculation module is used to calculate the phase difference of the longest baseline in the antenna array by a virtual baseline method, and then solve the sinα corresponding to the incident angle α of the electromagnetic wave signal according to the phase difference of the longest baseline; the second calculation module is used to calculate the actual phase difference of each real baseline in the antenna array by a staggered baseline method, and then solve the sinβ array corresponding to the incident angle β of the electromagnetic wave signal according to the actual phase difference of each real baseline; the third calculation module is used to subtract sinα from all sinβ elements in the sinβ array to obtain an error array, find the minimum error through the index, and solve the incident angle β of the electromagnetic wave signal according to the sinβ element corresponding to the minimum error.

[0111] In this embodiment, the intelligent electromagnetic perception system also includes a fusion filter calculation module, which is used to perform fusion filtering on the incident angle α and the incident angle β obtained by N times of calculation, and calculate the incident angle γ of the corrected electromagnetic wave signal. The interferometer direction finding system can accurately obtain the incident angle of the electromagnetic wave signal at a high speed, and can provide real-time and effective target orientation for subsequent terminal guidance.

[0112] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. An interferometer direction finding method, characterized in that: The following steps are involved: The phase difference of the longest baseline in the antenna array is calculated by a virtual baseline method, and then sinα corresponding to the incident angle α of the electromagnetic wave signal is obtained according to the phase difference of the longest baseline; Calculating the actual phase difference of each real baseline in the antenna array by using the staggered baseline method, and then solving the sinβ array corresponding to the incident angle β of the electromagnetic wave signal according to the actual phase difference of each real baseline; Subtract sinα from all sinβ elements in the sinβ array to obtain an error array, find the minimum error through the index, and solve the incident angle β of the electromagnetic wave signal according to the sinβ element corresponding to the minimum error.

2. The interferometer direction finding method according to claim 1, characterized in that: Also includes the steps: Performing N direction finding on the electromagnetic wave signal, calculating the incident angle α and the incident angle β by using the virtual baseline method and the staggered baseline method respectively in each direction finding; The incident angle α and the incident angle β obtained by N calculations are subjected to fusion filtering to obtain the incident angle γ of the corrected electromagnetic wave signal, wherein the fusion filtering is calculated according to the following formula: Wherein, N is the number of direction finding times, N≥1; λ is the filter coefficient, which is obtained through expert experience.

3. The interferometer direction finding method according to claim 1, characterized in that: Calculating the actual phase difference of each real baseline in the antenna array by the staggered baseline method includes the following steps: Assume that the actual phase difference of the electromagnetic wave signal reaching a real baseline is: in, is the actual phase difference corresponding to the nth real baseline; τ is the incident wavelength of the electromagnetic wave signal; d n is the length corresponding to the nth real baseline; is the measured phase difference corresponding to the nth real baseline; k n is the fuzzy number corresponding to the nth real baseline; n is a positive integer greater than or equal to 1; From formula (3), we can see that yes Remainders about 2π; Combining equation (2) and equation (3), we get: set up where m1, m2, ..., m n Coprime, then m1d1=m2d2=…=m n d n ,have From the above formula, we can set After rounding, it is modulo m n The remainder of According to the remainder theorem, we can solve for X, then The actual phase difference of the electromagnetic wave signal reaching each real baseline is obtained by calculating the fuzzy number corresponding to each real baseline.

4. The interferometer direction finding method according to claim 3, characterized in that: When calculating the actual phase difference of each real baseline in the antenna array by the staggered baseline method, jitter is taken into account. Assuming that the maximum error of jitter is Δε, the residue combination of the measured phase difference corresponding to each real baseline is: Substituting equation (8) into equation (6), we get k nleft , k n , k nright According to the obtained fuzzy numbers corresponding to each real baseline and the left and right error values ​​of each fuzzy number, the actual phase difference of the electromagnetic wave signal reaching each real baseline and the actual phase difference left error value and the actual phase difference right error value corresponding to each actual phase difference are calculated, and the n real baselines corresponding to the n real baselines are obtained. 3 actual phase difference combinations, each of the actual phase difference combinations includes n first phase differences corresponding to n real baselines, wherein each of the first phase differences is the actual phase difference, the actual phase difference left error value or the actual phase difference right error value.

5. The interferometer direction finding method according to claim 4, characterized in that: The n real baselines corresponding to the n real baselines are obtained by the staggered baseline method. 3 The actual phase difference combination also includes: Taking the length of each real baseline as the X-axis and the first phase difference in each actual phase difference combination as the Y-axis, performing least squares fitting to obtain a linear relationship between each real baseline and the first phase difference in each actual phase difference combination; Recalculate the second phase difference in each actual phase difference combination corresponding to each real baseline according to the linear relationship; Each sinβ corresponding to the incident angle β of the electromagnetic wave signal is obtained by solving each second phase difference obtained by the recalculation, and is saved as a sinβ array. The sinβ array includes n 3 sinβ elements.

6. An interferometer direction finding system, characterized in that: include: A first calculation module is used to calculate the phase difference of the longest baseline in the antenna array by a virtual baseline method, and then solve sinα corresponding to the incident angle α of the electromagnetic wave signal according to the phase difference of the longest baseline; A second calculation module is used to calculate the actual phase difference of each real baseline in the antenna array by using a staggered baseline method, and then solve the sinβ array corresponding to the incident angle β of the electromagnetic wave signal according to the actual phase difference of each real baseline; The third calculation module is used to subtract sinα from all sinβ elements in the sinβ array to obtain an error array, find the minimum error through indexing, and solve the incident angle β of the electromagnetic wave signal according to the sinβ element corresponding to the minimum error.

7. The interferometer direction finding system according to claim 6, characterized in that: Also includes: The fusion filter calculation module is used to perform fusion filtering on the incident angle α and the incident angle β obtained by N times of calculation, and calculate the incident angle γ of the corrected electromagnetic wave signal.

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