A phase calibration method and device for a small interferometer system

Abstract

The present application belongs to the field of interferometer signal processing technology, and particularly relates to a phase calibration method and device for a small interferometer system, the method comprising: step S1, obtaining the signal frequency of the measured incoming wave signal, and searching the phase difference calibration table for different angle intervals of the calibration frequency point corresponding to the signal frequency; step S2, calculating the phase difference data vector relative to the reference measurement phase using the phase of the incoming wave signal measured by each receiving channel; step S3, traversing the phase difference calibration table, and determining the standard phase difference data vector in the phase difference calibration table that is closest to the phase difference data vector; step S4, estimating the azimuth angle interval and elevation angle interval of the incoming wave signal; step S5, determining the precise angle within the azimuth angle interval and elevation angle interval based on the longest baseline distance. The present application ensures the correctness of the interferometer direction-finding system's deambiguation and effectively improves the direction-finding accuracy of the interferometer direction-finding system.

Description

Technical Field

[0001] The present application belongs to the technical field of interferometer signal processing, and in particular relates to a phase calibration method and device for a small interferometer system. Background Art

[0002] In passive direction-finding technology, interferometer systems are widely used in aviation, astronomy, and military fields due to their advantages of high speed, high accuracy, and excellent sensitivity. Interferometer direction-finding systems use the difference in distance between the target's incoming signal and different antenna elements to derive the phase difference. This phase difference, which is proportional to the target's incoming signal angle, is then used to determine the target's direction. Therefore, deviations in phase and frequency measurements directly affect the accuracy of the target's incoming signal angle. With the development of digital frequency measurement receivers, existing frequency measurement technology is sufficient to meet the frequency accuracy requirements of interferometer direction-finding systems. Therefore, phase measurement errors are crucial to interferometer direction-finding accuracy.

[0003] Interferometer direction-finding systems used in engineering typically employ multi-channel receivers to measure signal phase differences. However, due to the manufacturing processes of components, cables, and other equipment, phase consistency deviations exist between different receiving channels. Furthermore, due to the limited platform used for small devices, the internal angles of the antenna are relatively crowded, making the phase error introduced by radomes made of different materials and processes more sensitive. The reflection and refraction effects caused by incoming signals penetrating the radome from different angles and reaching the antenna unit can further amplify this error, and in severe cases, even cause direction ambiguity. Therefore, the selection of a phase calibration method is particularly important for small-platform interferometer direction-finding systems.

[0004] The main phase calibration methods today are the external signal source method and the internal automatic calibration method. The external signal source method uses an external radiated signal input to the RF front end, and then generates phase data for different channels through the direction-finding receiver, thereby generating a phase difference data vector. Traversing all calibration frequency points can obtain a full-band phase difference data calibration table. This method is usually calibrated in the antenna normal direction. In practical applications, the measurement accuracy of the incident wave direction near the normal direction is relatively good. However, when the angle of the incoming wave differs too much from the antenna normal, especially under small aperture restrictions, the phase measurement error caused by the incoming wave signals at different angles penetrating the antenna cover will increase significantly, and in severe cases, it can lead to direction-finding errors. Unlike the external signal source method, the internal automatic calibration method uses an internal calibration source generated by the built-in frequency synthesis module. The calibration process does not pass through the antenna front end. Although it is less affected by the space environment, this method only compensates for the phase error of different channels and does not consider the phase error caused by the antenna cover.

[0005] Therefore, when performing phase calibration on small-aperture platform interferometer direction-finding systems (e.g., 200 mm or less), in addition to the phase error introduced by the inconsistency of the receiving channel, the phase measurement error caused by penetrating the radome from different angles must also be carefully considered. Summary of the Invention

[0006] In order to solve the above problems, the present application provides a phase calibration method and device for a small interferometer system, so as to expand the application capability of the interferometer direction-finding system in miniaturized equipment and promote the development of interferometer direction-finding technology.

[0007] The first aspect of the present application provides a phase calibration method for a small interferometer system, mainly comprising:

[0008] Step S1: Get the signal frequency of the measured incoming signal and find the calibration frequency point f corresponding to the signal frequency. k Phase difference calibration table for different angle intervals The phase difference calibration table The standard phase difference data vectors of different azimuth calibration points and different elevation calibration points are recorded in Where i is the azimuth calibration point number, j is the elevation calibration point number;

[0009] Step S2: Calculate the phase difference data vector relative to the reference measurement phase using the phase of the incoming wave signal measured by each receiving channel.

[0010] Step S3: traverse the phase difference calibration table Determine the phase difference calibration table Center and phase difference data vector The closest standard phase difference data vector

[0011] Step S4: Based on the closest standard phase difference data vector Determine the azimuth calibration point and the elevation calibration point, and then estimate the azimuth angle interval and the elevation angle interval of the incoming signal;

[0012] Step S5: Based on the phase difference data vector The azimuth angle is determined based on the longest azimuth baseline distance. Similarly, the phase difference data vector is used to determine the azimuth angle within the azimuth angle interval. The precise pitch angle within the pitch angle interval is determined by summing the longest pitch baseline distance.

[0013] Preferably, before step S1, the method further comprises constructing a phase difference calibration table by the following steps:

[0014] Step S11: Determine the longest baseline distance L in the azimuth direction of the antenna in the interferometer direction finding system. az , and the longest baseline distance L in pitch direction el ;

[0015] Step S12: For incoming waves of different signal frequencies, determine the maximum unambiguous angle θ in the azimuth direction based on the wavelength of the incoming wave signal. maz The maximum unambiguous angle θ with the pitch direction mel ;

[0016] Step S13: According to the required azimuth angle range θ az and pitch angle range θ el , determine the azimuth fuzzy number M az and the pitch fuzzy number M el ;

[0017] Step S14: Determine whether the azimuth fuzzy number M is not less than az The number of azimuth calibration points N az , and determine the pitch fuzzy number M el Number of pitch calibration points N el ;

[0018] Step S15: for each calibration frequency point f corresponding to the signal frequency k Perform full-angle calibration. For each calibration frequency point, record and store the phase difference data vector of each receiving channel measurement phase relative to the reference measurement phase at different angles as the standard phase difference data vector. By the standard phase difference data vector Forming a phase difference calibration table

[0019] Preferably, step S11 further includes calibrating the environment of the interferometer direction-finding system in a microwave darkroom.

[0020] Preferably, step S3 further comprises: calculating the phase difference calibration table The standard phase difference data vectors and the measured phase difference data vectors The Euclidean distance of the standard phase difference data vector is determined to be the closest standard phase difference data vector.

[0021] The second aspect of the present application provides a small interferometer system phase calibration device, mainly comprising:

[0022] Phase difference calibration table query module, used to obtain the signal frequency of the measured incoming signal and find the calibration frequency point f corresponding to the signal frequency k Phase difference calibration table for different angle intervals The phase difference calibration table The standard phase difference data vectors of different azimuth calibration points and different elevation calibration points are recorded in Where i is the azimuth calibration point number, j is the elevation calibration point number;

[0023] Phase difference data vector calculation module, used to calculate the phase difference data vector relative to the reference measurement phase using the phase of the incoming wave signal measured by each receiving channel

[0024] Standard phase difference data vector matching module, used to traverse the phase difference calibration table Determine the phase difference calibration table Center and phase difference data vector The closest standard phase difference data vector

[0025] Angle interval calculation module, used to calculate the angle interval according to the closest standard phase difference data vector Determine the azimuth calibration point and the elevation calibration point, and then estimate the azimuth angle interval and the elevation angle interval of the incoming signal;

[0026] Precise angle calculation module for phase difference data vector The azimuth angle is determined based on the longest azimuth baseline distance. Similarly, the phase difference data vector is used to determine the azimuth angle within the azimuth angle interval. The precise pitch angle within the pitch angle interval is determined by summing the longest pitch baseline distance.

[0027] Preferably, the phase difference calibration table query module includes a phase difference calibration table construction unit for constructing a phase difference calibration table The phase difference calibration table construction unit includes:

[0028] The longest baseline distance determination subunit is used to determine the longest baseline distance L in the azimuth direction of the antenna in the interferometer direction finding system. az , and the longest baseline distance L in pitch direction el ;

[0029] The maximum unambiguous angle calculation subunit is used to determine the maximum unambiguous angle θ of the azimuth based on the wavelength of the incoming wave signal for different signal frequencies. maz The maximum unambiguous angle θ with the pitch direction mel ;

[0030] The fuzzy number determination subunit is used to determine the azimuth angle range θ according to the requirements az and pitch angle range θ el , determine the azimuth fuzzy number M az and the pitch fuzzy number M el ;

[0031] The calibration point determination subunit is used to determine the azimuth ambiguity number M that is not less than az The number of azimuth calibration points N az , and determine the pitch fuzzy number M elNumber of pitch calibration points N el ;

[0032] The full-angle calibration subunit is used to calibrate each frequency point f corresponding to the signal frequency. k Perform full-angle calibration. For each calibration frequency point, record and store the phase difference data vector of each receiving channel measurement phase relative to the reference measurement phase at different angles as the standard phase difference data vector. By the standard phase difference data vector Forming a phase difference calibration table

[0033] Preferably, the interferometer direction-finding system calibration environment is carried out in a microwave darkroom.

[0034] Preferably, the standard phase difference data vector matching module includes a Euclidean distance matching unit for respectively calculating the phase difference calibration table The standard phase difference data vectors and the measured phase difference data vectors The Euclidean distance of the standard phase difference data vector is determined to be the closest standard phase difference data vector.

[0035] This application targets an interferometer direction-finding system for small-aperture antenna arrays. In a darkroom environment, a standard radiation source is used to collect two-dimensional, full-angle phase difference data in azimuth and elevation for each calibration frequency point. A phase difference calibration table is generated and stored in the system's internal storage. During actual testing, the incoming signal phase difference data vector is calculated based on different channels. A correlation method is used to find the closest phase difference data vector based on the signal frequency, thereby determining the incoming signal angle range. The precise angle of the incoming signal is then calculated using the longest baseline in the interferometer system.

[0036] This application takes into account the angle information of the incoming signal, greatly reducing the relative phase error caused by the incoming signals at different angles penetrating the antenna cover, which not only ensures the correctness of the interferometer direction-finding system's deambiguation, but also effectively improves the direction-finding accuracy of the interferometer direction-finding system. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a flow chart of a preferred embodiment of a phase calibration method for a small interferometer system of the present application. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the implementation of this application will be described in more detail below in conjunction with the drawings in the implementation of this application. In the drawings, the same or similar numbers throughout represent the same or similar elements or elements with the same or similar functions. The described implementation is a part of the implementation of this application, not all of the implementations. The implementation described below with reference to the drawings is exemplary and is intended to be used to explain this application, and should not be understood as a limitation on this application. Based on the implementation in this application, all other implementations obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. The implementation of this application is described in detail below in conjunction with the drawings.

[0039] The first aspect of the present application provides a phase calibration method for a small interferometer system, such as Figure 1 As shown, the method mainly includes:

[0040] Step S1: Get the signal frequency of the measured incoming signal and find the calibration frequency point f corresponding to the signal frequency. k Phase difference calibration table for different angle intervals The phase difference calibration table The standard phase difference data vectors of different azimuth calibration points and different elevation calibration points are recorded in Where i is the azimuth calibration point number, and j is the elevation calibration point number.

[0041] In step S1, the corresponding calibration frequency point f can be found according to the actual signal frequency. k Phase difference calibration table Phase difference calibration table The phase difference calibration table is obtained in advance through experiments and stored in the database. It includes multiple calibration frequency points f k Corresponding to a phase difference calibration table Each phase difference calibration table It is essentially a two-dimensional matrix, each element in the matrix is ​​a standard phase difference data vector Use subscripts i, j, and f k Indicates the calibration frequency f k The data in row i and column j of .

[0042] In some optional embodiments, before step S1, the phase difference calibration table is further constructed by the following steps:

[0043] Step S11: Determine the longest baseline distance L in the azimuth direction of the antenna in the interferometer direction finding system. az , and the longest baseline distance L in pitch direction el.

[0044] In step S11, first, the interferometer direction-finding system is calibrated in a microwave darkroom, and then the antenna array form in the interferometer direction-finding system is determined according to requirements, and the longest baseline distances in azimuth and elevation are determined.

[0045] Step S12: For incoming waves of different signal frequencies, determine the maximum unambiguous angle θ in the azimuth direction based on the wavelength of the incoming wave signal. maz The maximum unambiguous angle θ with the pitch direction mel .

[0046] In step S12, the maximum unambiguous angle θ in the azimuth direction is determined according to the following formula: maz :

[0047]

[0048] Among them, λ is the wavelength of the incoming signal, which has a corresponding relationship with the signal frequency. For example, for an incoming signal with a signal frequency of 15 GHz, assuming that its longest baseline distance in azimuth is L az is 100mm. After calculation, the maximum unambiguous angle θ maz It is approximately ±5.7°. That is, the target angle measured by the direction finder within the range of ±5.7° is accurate, and beyond this angle, the measured target angle is a fuzzy value.

[0049] Step S13: According to the required azimuth angle range θ az and pitch angle range θ el , determine the azimuth fuzzy number M az and the pitch fuzzy number M el .

[0050] In step S13, it is assumed that the maximum unambiguous angle θ in the azimuth direction is maz The maximum unambiguous angle θ with the pitch direction mel After calculation in step S12, the values ​​are both ±5.7°, while the required azimuth angle range θ az and pitch angle range θ el Usually it is ±45° or ±60°, so the fuzzy number is 45 / 5.7 or 60 / 5.7, and then round up.

[0051] Step S14: Determine whether the azimuth fuzzy number M is not less than az The number of azimuth calibration points N az , and determine the pitch fuzzy number M el Number of pitch calibration points N el .

[0052] In step S14, in order to ensure that there is no phase ambiguity in direction finding, the number of calibration points in azimuth and elevation for each calibration frequency point should be greater than the corresponding ambiguity number, that is, the number of calibration points in azimuth direction N az >M az , the number of pitch calibration points N el >M el The angle value to be calibrated of the two-dimensional dot matrix of each calibration frequency point is determined in combination with the direction finding range.

[0053] Step S15: for each calibration frequency point f corresponding to the signal frequency k Perform full-angle calibration. For each calibration frequency point, record and store the phase difference data vector of each receiving channel measurement phase relative to the reference measurement phase at different angles as the standard phase difference data vector. By the standard phase difference data vector Forming a phase difference calibration table

[0054] In step S15, all calibration frequency points f0, f1, f2, ..., f m Perform full-angle calibration in sequence, where f0 is the minimum frequency to be calibrated, f m is the maximum frequency point to be calibrated, for example, 1GHz, 2GHz, 2GHz, 8GHz, 16GHz, etc., a total of m signal frequencies corresponding to the calibration frequency points. For each calibration frequency point, record and store the phase difference data vector of each receiving channel measurement phase relative to the reference measurement phase at different angles. Assume that for the kth calibration frequency point f k , which forms the phase difference calibration table Including N el Row, N az Column elements, each element is a standard phase difference data vector Where i and j correspond to the azimuth and elevation angles to be calibrated, respectively, as shown in the following matrix:

[0055]

[0056] For example, assuming that the azimuth and elevation angle measurement ranges are both ±60°, with a total scanning range of 120°, the maximum unambiguous angle θ in azimuth is maz The maximum unambiguous angle θ with the pitch direction mel The scanning range is ±20°, and the total scanning range is 40°. The number of calibration points in azimuth and elevation is 3. Assuming that the number of calibration points in azimuth and elevation is 4, the phase difference calibration table is It is a 4*4 two-dimensional matrix, each calibration point covers a 30° scanning range, where It can represent the standard phase difference data vector between -60° and -30° in azimuth and -60° and -30° in elevation. It can represent the standard phase difference data vector between -60° and -30° in azimuth and -30° to 0° in elevation. It can represent the standard phase difference data vector between -30° and 0° in azimuth and -60° to -30° in elevation.

[0057] The database pre-stores the above m phase difference calibration tables That is, in actual use, a corresponding phase difference calibration table can be matched according to any measured signal frequency. In an alternative implementation, if there is an uncovered signal frequency in the database, the phase difference calibration table of the corresponding signal frequency can be obtained by matching the nearest adjacent signal frequency.

[0058] Step S2: Calculate the phase difference data vector relative to the reference measurement phase using the phase of the incoming wave signal measured by each receiving channel.

[0059] Step S3: traverse the phase difference calibration table Determine the phase difference calibration table Center and phase difference data vector The closest standard phase difference data vector

[0060] This step is used to traverse the phase difference calibration table All the standard phase difference data vectors in the , use the correlation method to find the phase difference data vector with the measured phase difference data vector The closest standard phase difference data vector. In some optional embodiments, step S3 further includes: calculating the phase difference calibration table The standard phase difference data vectors and the measured phase difference data vectors The Euclidean distance of the standard phase difference data vector is determined to be the closest standard phase difference data vector.

[0061] Still using the aforementioned 4*4 phase difference calibration table For example, assuming that the standard phase difference data vector The phase difference data vector with the actual measurement The Euclidean distance is the smallest, then the standard phase difference data vector Correct the phase of the incoming signal.

[0062] Step S4: Based on the closest standard phase difference data vector Determine the azimuth calibration point and the elevation calibration point, and then estimate the azimuth angle interval and the elevation angle interval of the incoming signal.

[0063] As described in step S3, the standard phase difference data vector It means that the azimuth angle range is between -30° and 0°, and the pitch angle range is also between -30° and 0°.

[0064] Step S5: Based on the phase difference data vector The azimuth angle is determined based on the longest azimuth baseline distance. Similarly, the phase difference data vector is used to determine the azimuth angle within the azimuth angle interval. The precise pitch angle within the pitch angle interval is determined by summing the longest pitch baseline distance.

[0065] In this step, the corresponding precise angle θ can be calculated according to the following formula:

[0066]

[0067] Where λ is the wavelength of the incoming signal, and L is the longest baseline distance, i.e. the longest baseline distance L in the azimuth direction mentioned above. az , and the longest baseline distance L in pitch direction el , The phase difference data corresponding to the longest measured baseline. Due to the existence of phase ambiguity, the phase difference can be calculated into multiple specific angle values. Then, according to the azimuth angle interval and the pitch angle interval determined in step S4, the angle falling into the interval is determined to be the unambiguous and precise angle of the incoming signal.

[0068] The second aspect of the present application provides a small interferometer system phase calibration device corresponding to the above method, mainly comprising:

[0069] Phase difference calibration table query module, used to obtain the signal frequency of the measured incoming signal and find the calibration frequency point f corresponding to the signal frequency k Phase difference calibration table for different angle intervals The phase difference calibration table The standard phase difference data vectors of different azimuth calibration points and different elevation calibration points are recorded in Where i is the azimuth calibration point number, j is the elevation calibration point number;

[0070] Phase difference data vector calculation module, used to calculate the phase difference data vector relative to the reference measurement phase using the phase of the incoming wave signal measured by each receiving channel

[0071] Standard phase difference data vector matching module, used to traverse the phase difference calibration table Determine the phase difference calibration table Center and phase difference data vector The closest standard phase difference data vector

[0072] Angle interval calculation module, used to calculate the angle interval according to the closest standard phase difference data vector Determine the azimuth calibration point and the elevation calibration point, and then estimate the azimuth angle interval and the elevation angle interval of the incoming signal;

[0073] Precise angle calculation module for phase difference data vector The azimuth angle is determined based on the longest azimuth baseline distance. Similarly, the phase difference data vector is used to determine the azimuth angle within the azimuth angle interval. The precise pitch angle within the pitch angle interval is determined by summing the longest pitch baseline distance.

[0074] In some optional embodiments, the phase difference calibration table query module includes a phase difference calibration table construction unit for constructing a phase difference calibration table. The phase difference calibration table construction unit includes:

[0075] The longest baseline distance determination subunit is used to determine the longest baseline distance L in the azimuth direction of the antenna in the interferometer direction finding system. az , and the longest baseline distance L in pitch direction el ;

[0076] The maximum unambiguous angle calculation subunit is used to determine the maximum unambiguous angle θ of the azimuth based on the wavelength of the incoming wave signal for different signal frequencies. maz The maximum unambiguous angle θ with the pitch direction mel ;

[0077] The fuzzy number determination subunit is used to determine the azimuth angle range θ according to the requirements az and pitch angle range θ el , determine the azimuth fuzzy number M az and the pitch fuzzy number M el ;

[0078] The calibration point determination subunit is used to determine the azimuth ambiguity number M that is not less than az The number of azimuth calibration points N az , and determine the pitch fuzzy number M el Number of pitch calibration points N el ;

[0079] The full-angle calibration subunit is used to calibrate each frequency point f corresponding to the signal frequency. k Perform full-angle calibration. For each calibration frequency point, record and store the phase difference data vector of each receiving channel measurement phase relative to the reference measurement phase at different angles as the standard phase difference data vector. By the standard phase difference data vector Forming a phase difference calibration table

[0080] In some optional embodiments, the interferometer direction-finding system calibration environment is carried out in a microwave darkroom.

[0081] In some optional embodiments, the standard phase difference data vector matching module includes a Euclidean distance matching unit for respectively calculating the phase difference calibration table The standard phase difference data vectors and the measured phase difference data vectors The Euclidean distance of the standard phase difference data vector is determined to be the closest standard phase difference data vector.

[0082] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A phase calibration method for a small interferometer system, characterized in that: include: Step S1: Get the signal frequency of the measured incoming signal and find the calibration frequency point f corresponding to the signal frequency. k Phase difference calibration table for different angle intervals The phase difference calibration table The standard phase difference data vectors of different azimuth calibration points and different elevation calibration points are recorded in Where i is the azimuth calibration point number, j is the elevation calibration point number; Step S2: Calculate the phase difference data vector relative to the reference measurement phase using the phase of the incoming wave signal measured by each receiving channel. Step S3: traverse the phase difference calibration table Determine the phase difference calibration table Center and phase difference data vector The closest standard phase difference data vector Step S4: Based on the closest standard phase difference data vector Determine the azimuth calibration point and the elevation calibration point, and then estimate the azimuth angle interval and the elevation angle interval of the incoming signal; Step S5: Based on the phase difference data vector The azimuth angle is determined based on the longest azimuth baseline distance. Similarly, the phase difference data vector is used to determine the azimuth angle within the azimuth angle interval. The precise pitch angle within the pitch angle interval is determined by summing the longest pitch baseline distance.

2. The phase calibration method of a small interferometer system according to claim 1, wherein: Before step S1, the phase difference calibration table is constructed by the following steps: Step S11: Determine the longest baseline distance L in the azimuth direction of the antenna in the interferometer direction finding system. az , and the longest baseline distance L in pitch direction el ; Step S12: For incoming waves of different signal frequencies, determine the maximum unambiguous angle θ in the azimuth direction based on the wavelength of the incoming wave signal. maz The maximum unambiguous angle θ with the pitch direction mel ; Step S13: According to the required azimuth angle range θ az and pitch angle range θ el , determine the azimuth fuzzy number M az and the pitch fuzzy number M el ; Step S14: Determine whether the azimuth fuzzy number M is not less than az The number of azimuth calibration points N az , and determine the pitch fuzzy number M el Number of pitch calibration points N el ; Step S15: for each calibration frequency point f corresponding to the signal frequency k Perform full-angle calibration. For each calibration frequency point, record and store the phase difference data vector of each receiving channel measurement phase relative to the reference measurement phase at different angles as the standard phase difference data vector. By the standard phase difference data vector Forming a phase difference calibration table 3. The phase calibration method of a small interferometer system according to claim 2, wherein: Step S11 further includes calibrating the environment of the interferometer direction-finding system in a microwave darkroom.

4. The phase calibration method of a small interferometer system according to claim 1, wherein: Step S3 further includes: calculating the phase difference calibration table The standard phase difference data vectors and the measured phase difference data vectors The Euclidean distance of the standard phase difference data vector is determined to be the closest standard phase difference data vector.

5. A small interferometer system phase calibration device, characterized in that: include: Phase difference calibration table query module, used to obtain the signal frequency of the measured incoming signal and find the calibration frequency point f corresponding to the signal frequency k Phase difference calibration table for different angle intervals The phase difference calibration table The standard phase difference data vectors of different azimuth calibration points and different elevation calibration points are recorded in Where i is the azimuth calibration point number, j is the elevation calibration point number; Phase difference data vector calculation module, used to calculate the phase difference data vector relative to the reference measurement phase using the phase of the incoming wave signal measured by each receiving channel Standard phase difference data vector matching module, used to traverse the phase difference calibration table Determine the phase difference calibration table Center and phase difference data vector The closest standard phase difference data vector Angle interval calculation module, used to calculate the angle interval according to the closest standard phase difference data vector Determine the azimuth calibration point and the elevation calibration point, and then estimate the azimuth angle interval and the elevation angle interval of the incoming signal; Precise angle calculation module for phase difference data vector The azimuth angle is determined based on the longest azimuth baseline distance. Similarly, the phase difference data vector is used to determine the azimuth angle within the azimuth angle interval. The precise pitch angle within the pitch angle interval is determined by summing the longest pitch baseline distance.

6. The phase calibration device of a small interferometer system according to claim 5, characterized in that: The phase difference calibration table query module includes a phase difference calibration table construction unit for constructing a phase difference calibration table The phase difference calibration table construction unit includes: The longest baseline distance determination subunit is used to determine the longest baseline distance L in the azimuth direction of the antenna in the interferometer direction finding system. az , and the longest baseline distance L in pitch direction el ; The maximum unambiguous angle calculation subunit is used to determine the maximum unambiguous angle θ of the azimuth based on the wavelength of the incoming wave signal for different signal frequencies. maz The maximum unambiguous angle θ with the pitch direction mel ; The fuzzy number determination subunit is used to determine the azimuth angle range θ according to the requirements az and pitch angle range θ el , determine the azimuth fuzzy number M az and the pitch fuzzy number M el ; The calibration point determination subunit is used to determine the azimuth ambiguity number M that is not less than az The number of azimuth calibration points N az , and determine the pitch fuzzy number M el Number of pitch calibration points N el ; The full-angle calibration subunit is used to calibrate each frequency point f corresponding to the signal frequency. k Perform full-angle calibration. For each calibration frequency point, record and store the phase difference data vector of each receiving channel measurement phase relative to the reference measurement phase at different angles as the standard phase difference data vector. By the standard phase difference data vector Forming a phase difference calibration table 7. The phase calibration device of a small interferometer system according to claim 6, characterized in that: The interferometer direction finding system calibration environment is carried out in a microwave anechoic chamber.

8. The phase calibration device of a small interferometer system according to claim 5, wherein: The standard phase difference data vector matching module includes a Euclidean distance matching unit for calculating the phase difference calibration table The standard phase difference data vectors and the measured phase difference data vectors The Euclidean distance of the standard phase difference data vector is determined to be the closest standard phase difference data vector.

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