Phased array based interferometer direction finding method and system

Abstract

This invention discloses an interferometer direction finding method and system based on phased array guidance, belonging to the field of electromagnetic spectrum monitoring and countermeasures. The method includes: arranging a narrow-beam phased array in an interferometer antenna array; when a radiation source projects a signal from the far field at an angle θ relative to the antenna array normal and the radiation source is located within the beam currently scanned by the narrow-beam phased array antenna A1, all antennas in the antenna array receive the radiation source signal; utilizing the beam scanning characteristics of the narrow-beam phased array to constrain the direction of arrival of the radiation source signal, thereby constraining the longest unambiguous phase period range of the baseline that the interferometer direction finding algorithm needs to traverse; at this time, using the phase difference of each baseline output by the phase comparator, the current scanning angle of the narrow-beam phased array, and the baseline information of the deployed phased array as inputs to the direction finding algorithm, and outputting the direction finding result after calculation and processing. This invention reduces the number of traversals in the interferometer direction finding algorithm, reduces the complexity of the interferometer direction finding method, and improves the probability of correct direction finding by the interferometer.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic spectrum monitoring and countermeasures, and more specifically, to an interferometer direction finding method and system based on phased array guidance. Background Technology

[0002] Electromagnetic signal detection and direction finding are crucial requirements for electronic reconnaissance systems and spectrum monitoring systems. Due to their advantages in cost, angle measurement accuracy, and airspace coverage, interferometers are the most commonly used method for high-precision direction finding of radiation sources and are now widely applied in related fields.

[0003] Commonly used interferometer direction finding algorithms mainly include the stepwise unambiguous interferometer direction finding algorithm and the full-baseline weighted projection spatial mean square error minimum algorithm. The stepwise unambiguous interferometer direction finding algorithm calculates the unambiguous phase difference of each interferometer baseline in ascending order of size, and calculates the direction of arrival of the radiation source signal based on the unambiguous phase difference of the longest baseline (corresponding to the two farthest antennas). While the stepwise unambiguous interferometer direction finding algorithm has low complexity, its unambiguity resolution is greatly affected by the phase error of each baseline; the unambiguity resolution probability decreases significantly when the antenna phase error measurement accuracy is low. The full-baseline weighted projection spatial mean square error minimum algorithm is currently widely used and has good angle measurement accuracy, but this algorithm traverses all possible directions of arrival for the longest baseline, leading to the following drawbacks:

[0004] a) Due to the need to perform fuzzy resolution by traversing the range of incoming wave directions, the algorithm has high complexity;

[0005] b) The probability of deambiguity errors in angle measurement is relatively high. If the range of incoming wave directions is too large, and the antenna phase error measurement accuracy is low and the baseline phase difference error is large, it is easy to obtain the minimum mean square error result when traversing the wrong incoming wave direction, thus leading to deambiguity errors. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide an interferometer direction finding method and system based on phased array guidance. It optimizes the interferometer direction finding algorithm with the minimum mean square error of full baseline weighted projection to reduce the number of traversals, thereby reducing the complexity of the interferometer direction finding method and improving the probability of correct direction finding by the interferometer.

[0007] The objective of this invention is achieved through the following approach:

[0008] An interferometer direction finding method based on phased array guidance includes the following steps:

[0009] A narrow-beam phased array is arranged in the interferometer antenna array;

[0010] When the radiation source projects a signal from the far field at an angle θ relative to the antenna array and the radiation source is located within the beam currently being scanned by the narrow-beam phased array antenna A1, all antennas of the antenna array receive the radiation source signal.

[0011] The beam scanning characteristics of the narrow-beam phased array are used to constrain the direction of arrival of the radiation source signal, thereby constraining the longest unambiguous phase period range of the interferometer direction finding algorithm. At this time, the phase difference of each baseline output by the phase comparator, the current scanning angle of the narrow-beam phased array, and the baseline information of the deployed phased array are used as inputs to the direction finding algorithm. After calculation and processing, the direction finding result is output, thus completing the interferometer direction finding.

[0012] Furthermore, the step of arranging a narrow-beam phased array in the interferometer antenna array includes the following sub-steps:

[0013] According to A1A2, A2A3, ..., A N-1 A N The baseline lengths are d1, d2, ..., d N-1 The baseline configuration is an interferometer system antenna array arranged in a linear array; when the interferometer system is powered on, all antennas and corresponding radio frequency channels complete phase correction.

[0014] Furthermore, when all antennas receive the far-field projected signal from the radiation source, the following steps are included:

[0015] Record the beam scanning angle θ of the narrow-beam phased array antenna A1 at this time, and record the baselines A1A2, A2A3, ..., A1A2 at this time. N-1 A N There are fuzzy phase differences φ1, φ2, ..., φ N-1 ;

[0016] Then, the basic baselines A1A2, A2A3, ..., A N-1 A N Extend to virtual baselines A1A3, A2A4, ..., A N-2 A N A1A4, A2A5, ..., A N-3 A N …、A1A N At this point, the baseline set is {A1A2, A2A3, ..., A...} N-1 A N A1A3, A2A4, ..., A N-2 A N A1A4, A2A5, ..., A N-3 A N …、A1A N The baseline lengths {D1, D2, ..., D} of all baselines are calculated based on the baseline configuration and the fuzzy phase difference of the base baseline. end} and has a fuzzy phase difference Based on the antenna baseline configuration method, the order of this baseline length and baseline phase difference is related to the baseline set {A1A2, A2A3, ..., A...}. N-1 A N A1A3, A2A4, ..., A N-2 A N A1A4, A2A5, ..., A N-3 A N …、A1A N The order of} is consistent.

[0017] Furthermore, the step of constraining the direction of arrival of the radiation source signal by utilizing the beam scanning characteristics of the narrow-beam phased array based on the narrow-beam phased array antenna, and thus constraining the longest unambiguous phase period range of the baseline that the interferometer direction-finding algorithm needs to traverse, includes the following sub-steps:

[0018] Based on the current scanning angle of the phased array beam and beam scanning angle error δ θ The ergodicity of the incoming wave direction θ of the radiation source signal is constrained, and the constraint range is... Where k is the longest baseline D end The corresponding unambiguous phase period n end The multiple of the constraints traversed are system parameters; according to the interferometer direction finding formula... Unambiguous phase corresponding to the longest baseline To obtain n end The range of values ​​is

[0019] Further, the step of using the phase difference of each baseline output by the phase comparator, the current scanning angle of the narrow-beam phased array, and the deployed phased array baseline information as inputs to the direction-finding algorithm, and outputting the direction-finding result after calculation and processing, includes the following sub-steps:

[0020] For unambiguous phase period n end The process involves iterating through the data, with each iteration including the following steps:

[0021] a) According to n end The ambiguous phase difference between the current value and the measured baselines Based on the direction-finding formula derived from interferometers The unambiguous phase period n of each baseline is derived by deduction. i And record it;

[0022] b) According to the interferometer direction finding formula Calculate the sine value sinθ of the incoming wave direction for each baseline estimate. i And record it;

[0023] c) Construct the azimuth error vector for all baselines. Calculate the variance var of the azimuth sine error vector;

[0024] After completing the traversal, search for the minimum value var of the variance of the sine error vector of the position in each traversal. min And extract the longest baseline unambiguous phase period n corresponding to it. end According to the interferometer direction finding formula The algorithm ultimately estimates the direction of arrival of the wave.

[0025] Furthermore, the value of k ranges from 2 to 5.

[0026] Furthermore, the beam scanning angle error δ θ It depends on the antenna characteristics.

[0027] Furthermore, the antenna array contains only one narrow-beam phased array antenna, while the remaining antennas are all conventional antennas.

[0028] Furthermore, the arrangement of a narrow-beam phased array in the interferometer antenna array specifically involves replacing the first antenna of the interferometer with a narrow-beam phased array.

[0029] An interferometer direction finding system based on phased array guidance includes an antenna array, a receiver, a phase comparator, and a processor. The antenna array is a linear array, with the first antenna being a narrow-beam phased array and the remaining antennas being conventional antennas. After receiving the antenna signals, the receiver transmits them to the phase comparator. The phase comparator outputs the phase difference of each baseline, the current scanning angle of the narrow-beam phased array, and the baseline information of the deployed phased array. The phase difference of each baseline, the current scanning angle of the narrow-beam phased array, and the baseline information of the deployed phased array are used as inputs to the direction finding algorithm. After processing by the processor, the direction finding result is output, thereby completing the interferometer direction finding. The system also includes a method for executing any of the methods described above.

[0030] The beneficial effects of this invention include:

[0031] The technical solution of this invention replaces a conventional antenna in a traditional interferometer direction-finding antenna array with a simple narrow-beam phased array. It utilizes the beam scanning characteristics of the narrow-beam phased array to constrain the direction of arrival of the radiation source signal, thereby constraining the longest unambiguous phase period range of the baseline that the interferometer direction-finding algorithm needs to traverse. This reduces the number of traversals of the interferometer direction-finding algorithm at a relatively low cost. The achieved effects are mainly reflected in two aspects:

[0032] a) Reduce algorithm complexity and improve algorithm efficiency: The optimization of the number of traversals in the interferometer direction finding algorithm is mainly determined by the direction of the incoming wave from the radiation source; the smaller the direction of the incoming wave, the greater the reduction in the number of traversals. Through the technical solution of this invention, the number of traversals in the algorithm for minimizing the mean square error of the full baseline weighted projection space can be reduced by more than 30%.

[0033] b) Improving the probability of correct direction finding in the interferometer direction finding algorithm: One reason for the deambiguity error in the interferometer direction finding algorithm is that it needs to consider all incoming wave directions of the radiation source signal and traverse the unambiguous phase period corresponding to the longest baseline accordingly. When the phase error is large, the redundant traversal will lead to incorrect deambiguity results. The technical solution of this invention constrains the incoming wave direction of the radiation source signal, greatly reducing the invalid traversal of the unambiguous phase period of the longest baseline, fundamentally reducing the possibility of deambiguity errors in the interferometer, improving the probability of correct direction finding in the interferometer direction finding algorithm, and the effect is more obvious when the phase error is larger. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the direction finding principle of a multi-baseline phase interferometer.

[0036] Figure 2 This is a flowchart of a method according to an embodiment of the present invention.

[0037] Figure 3 This is a comparison chart showing the correct direction finding probabilities when using only an interferometer and using an interferometer + phased array system (k value is 3) when the electromagnetic signal arrival direction is 10° to 45° in a phase error range of 0 to 30°.

[0038] Figure 4 This is a comparison chart showing the number of iterations of algorithms using only an interferometer and an interferometer + phased array system (k value is 3) when the electromagnetic signal arrival direction is 10° to 45° in a phase error range of 0 to 30°. Detailed Implementation

[0039] All features disclosed in all embodiments of this specification, or steps in all methods or processes implied in the disclosure, may be combined and / or extended or replaced in any way, except for mutually exclusive features and / or steps.

[0040] In view of the problems mentioned in the background, the inventors of this invention, after creative analysis and reflection, discovered that the full-baseline weighted projection spatial mean square error minimum interferometer algorithm suffers from high algorithm complexity and low probability of correct direction finding because it traverses all possible incoming wave directions of the longest baseline. The technical solution of this invention replaces any antenna of a traditional multi-baseline interferometer with a simple narrow-beam phased array. The range of incoming wave directions scanned by the phased array constrains the incoming wave direction of the longest baseline of the interferometer, thereby reducing the traversal range of the interferometer direction-finding algorithm.

[0041] In a further inventive concept, the principle of the phase interferometer direction finding system is described in [link to inventive concept]. Figure 1 Antenna A1 is a simple narrow-beam phased array antenna with continuous beam scanning; antennas A2 to A1 are... N This is a conventional antenna. The antenna array, composed of all the antennas, is arranged according to... Figure 1 The baseline distance configuration shown is arranged in a linear array and has been phase-corrected to achieve phase consistency. When the radiation source projects a signal from the far field at an angle θ relative to the antenna array normal and the radiation source is located within the beam currently scanned by antenna A1, all antennas in the system simultaneously receive the radiation source signal. At this time, the phase difference of each baseline output by the phase comparator, the current scanning angle of the narrow-beam phased array, and the deployed phased array baseline information are used as inputs to the direction-finding algorithm. After calculation and processing, the direction-finding result is output, thereby completing the interferometer direction finding. In a specific implementation, the following steps are included:

[0042] Step 1: According to A1A2, A2A3, ..., A N-1 A N The baseline lengths are d1, d2, ..., d N-1 The baseline configuration uses a linear array of antennas for the interferometer system. Upon power-up, all antennas and their corresponding radio frequency channels undergo phase correction.

[0043] Step 2: When all antennas receive the far-field projected signal from the radiation source, record the beam scanning angle of the narrow-beam phased array antenna A1 at this time. And at this time, the basic baselines A1A2, A2A3, ..., A N-1 A N The phase differences (i.e., phase differences without a phase period) are φ1, φ2, ..., φ N-1 ;

[0044] Step 3: Establish the basic baselines A1A2, A2A3, ..., A N-1 A N Extend to virtual baselines A1A3, A2A4, ..., A N-2 A N A1A4, A2A5, ..., A N-3 A N …、A1AN At this point, the baseline set is {A1A2, A2A3, ..., A...} N-1 A N A1A3, A2A4, ..., A N-2 A N A1A4, A2A5, ..., A N-3 A N …、A1A N The baseline lengths {D1, D2, ..., D} of all baselines are calculated based on the baseline configuration and the fuzzy phase difference of the base baseline. end} and has a fuzzy phase difference Based on the antenna baseline configuration method, the order of this baseline length and baseline phase difference is related to the baseline set {A1A2, A2A3, ..., A...}. N-1 A N A1A3, A2A4, ..., A N-2 A N A1A4, A2A5, ..., A N-3 A N …、A1A N The order of} is completely consistent;

[0045] Step 4: Based on the current scanning angle of the phased array beam and beam scanning angle error (rms) δ θ The ergodicity of the incoming wave direction θ of the radiation source signal is constrained, and the constraint range is... Where k is the longest baseline D end The corresponding unambiguous phase period n end The traversal constraint multiple is a system parameter, typically ranging from 2 to 5; beam scanning angle error δ θ Determined by antenna characteristics. According to the interferometer direction-finding formula. Unambiguous phase corresponding to the longest baseline To obtain n end The range of values ​​is

[0046] Step 5: Apply the range of values ​​for n obtained in Step 3. end The process involves iterating through the data, with each iteration including the following steps:

[0047] a) According to n end The current value and the ambiguous phase difference between each baseline measured in step two Based on the direction-finding formula derived from interferometers The unambiguous phase period n of each baseline is derived by deduction. i And record it;

[0048] b) According to the interferometer direction finding formula Calculate the sine value sinθ of the incoming wave direction for each baseline estimate. i And record it;

[0049] c) Construct the azimuth error vector for all baselines. Calculate the variance var of the azimuth sine error vector;

[0050] Step 6: After completing the traversal, search for the minimum value var of the variance of the directional sinusoidal error vector in each traversal. min And extract the longest baseline unambiguous phase period n corresponding to it. end According to the interferometer direction finding formula The algorithm ultimately estimates the direction of arrival of the wave.

[0051] The technical solution of this invention also provides a rapid direction finding method for an interferometer based on phased array guidance, the implementation process of which is as follows: Figure 2 As shown. The implementation process of this invention will be described in detail with reference to specific implementation examples.

[0052] A typical three-baseline phase interferometer system is employed, covering a frequency range of 8 GHz to 12 GHz. The baseline configuration conforms to the baseline arrangement method within this operating frequency band and is arranged in a linear array. The first antenna of the interferometer is replaced with a narrow-beam phased array with a beamwidth of 10°. With the input system parameter k set to 3, simulations are performed with radiation source projection directions of 10°, 15°, 20°, 25°, 30°, 35°, 40°, and 45°, and root mean square errors of phase differences of 0°, 5°, 10°, 15°, 20°, 25°, and 30°, respectively. The interferometer + simple narrow-beam phased array system is compared with the conventional interferometer system in terms of direction finding accuracy probability and interferometer algorithm traversal count.

[0053] Step 1: Arrange the interferometer system's antenna array in a linear array according to the baseline configurations A1A2, A2A3, and A3A4, with baseline lengths of d1, d2, and d3 respectively. Antenna A1 is a simple narrow-beam phased array with a beamwidth of 5°. Power on the interferometer system, and all antennas and corresponding RF channels complete phase correction.

[0054] Step 2: When all antennas receive the far-field projected signal from the radiation source, record the beam scanning angle of the narrow-beam phased array antenna A1 at this time. (This angle is ±5° of the radiation source signal projection angle), and at this time, the ambiguous phase differences (i.e., phase differences without phase period) φ1, φ2, φ3 of the basic baselines A1A2, A2A3, and A3A4;

[0055] Step 3: Expand the basic baselines A1A2, A2A3, and A3A4 into virtual baselines A1A3, A2A4, and A1A4. At this point, the complete set of baselines is {A1A2, A2A3, A3A4, A1A3, A2A4, A1A4}. Based on the baseline configuration of this three-baseline phase interferometer implementation example and the fuzzy phase difference of the basic baselines, calculate the baseline lengths {D1 = d1, D2 = d1, D3 = d3, D4 = d1 + d2, D5 = d2 + d3, D6 = d1 + d2 + d3} and the fuzzy phase differences of all baselines.

[0056] Step 4: Based on the current scanning angle of the phased array beam and beam scanning angle error (rms) δ θ The ergodicity of the incoming wave direction θ of the radiation source signal is constrained. Since the system parameter k is 3 in this implementation example, the constraint range is... According to the interferometer direction finding formula Unambiguous phase corresponding to the longest baseline The range of values ​​for n6 is calculated as follows:

[0057] Step 5: Iterate through n6 according to the value range obtained in Step 3. Each iteration includes the following steps:

[0058] a) Based on the current value of n6 and the ambiguous phase difference of all baselines calculated in step three. Based on the direction-finding formula derived from interferometers Deducing the unambiguous phase period n of all baselines except the longest baseline i (i = 1, 2, 3, 4, 5) and record them;

[0059] b) According to the interferometer direction finding formula Calculate the sine value sinθ of the incoming wave direction for each baseline estimate. i And record it;

[0060] c) Construct the azimuth error vector for all baselines. Calculate the variance var of the azimuth sine error vector;

[0061] Step 6: After completing the traversal, search for the minimum value var of the variance of the directional sinusoidal error vector in each traversal. min And extract the longest baseline unambiguous phase period n corresponding to it. end According to the interferometer direction finding formula The algorithm ultimately estimates the direction of arrival of the wave.

[0062] Simulation results show that using an interferometer combined with a simple narrow-beam phased array system not only significantly reduces the number of traversals in the interferometer direction-finding algorithm (reducing the number of traversals to 35% when the incoming wave direction is 10° and to 70% when the incoming wave direction is 45°), but also improves the probability of correct direction finding by the interferometer in scenarios with high phase difference errors, especially when the incoming wave direction angle is small (the probability of correct direction finding by the interferometer can be increased by 10% when the incoming wave direction angle is 10°). Therefore, the technical solution of this invention has the effect of reducing the number of traversals in the interferometer direction-finding algorithm and improving the probability of correct direction finding by the interferometer.

[0063] It should be noted that, within the scope of protection defined in the claims of this invention, the following embodiments can be combined and / or extended or replaced in any logical manner from the above specific embodiments, such as the disclosed technical principles, disclosed technical features or implicitly disclosed technical features.

[0064] Example 1

[0065] An interferometer direction finding method based on phased array guidance includes the following steps:

[0066] A narrow-beam phased array is arranged in the interferometer antenna array;

[0067] When the radiation source projects a signal from the far field at an angle θ relative to the antenna array and the radiation source is located within the beam currently being scanned by the narrow-beam phased array antenna A1, all antennas of the antenna array receive the radiation source signal.

[0068] The beam scanning characteristics of the narrow-beam phased array are used to constrain the direction of arrival of the radiation source signal, thereby constraining the longest unambiguous phase period range of the interferometer direction finding algorithm. At this time, the phase difference of each baseline output by the phase comparator, the current scanning angle of the narrow-beam phased array, and the baseline information of the deployed phased array are used as inputs to the direction finding algorithm. After calculation and processing, the direction finding result is output, thus completing the interferometer direction finding.

[0069] Example 2

[0070] Based on Example 1, the step of arranging a narrow-beam phased array in the interferometer antenna array includes the following sub-steps:

[0071] According to A1A2, A2A3, ..., A N-1 A N The baseline lengths are d1, d2, ..., d N-1 The baseline configuration is an interferometer system antenna array arranged in a linear array; when the interferometer system is powered on, all antennas and corresponding radio frequency channels complete phase correction.

[0072] Example 3

[0073] Based on Example 2, when all antennas receive the far-field projected signal from the radiation source, the following steps are included:

[0074] Record the beam scanning angle of the narrow-beam phased array antenna A1 at this time. And record the baselines A1A2, A2A3, ..., A at this time. N-1 A N There are fuzzy phase differences φ1, φ2, ..., φ N-1 ;

[0075] Then, the basic baselines A1A2, A2A3, ..., A N-1 A N Extend to virtual baselines A1A3, A2A4, ..., A N-2 A N A1A4, A2A5, ..., A N-3 A N …、A1A N At this point, the baseline set is {A1A2, A2A3, ..., A...} N-1 A N A1A3, A2A4, ..., A N-2 A N A1A4, A2A5, ..., A N-3 A N …、A1A N The baseline lengths {D1, D2, ..., D} of all baselines are calculated based on the baseline configuration and the fuzzy phase difference of the base baseline. end} and has a fuzzy phase difference Based on the antenna baseline configuration method, the order of this baseline length and baseline phase difference is related to the baseline set {A1A2, A2A3, ..., A...}. N-1 A N A1A3, A2A4, ..., A N-2 A N A1A4, A2A5, ..., A N-3 A N …、A1A N The order of} is consistent.

[0076] Example 4

[0077] Based on Example 1, the step of constraining the direction of arrival of the radiation source signal by utilizing the beam scanning characteristics of the narrow-beam phased array antenna to constrain the longest unambiguous phase period range of the interferometer direction finding algorithm includes the following sub-steps:

[0078] Based on the current scanning angle of the phased array beam and beam scanning angle error δ θ The ergodicity of the incoming wave direction θ of the radiation source signal is constrained, and the constraint range is... Where k is the longest baseline D end The corresponding unambiguous phase period n end The multiple of the constraints traversed are system parameters; according to the interferometer direction finding formula... Unambiguous phase corresponding to the longest baseline To obtain n end The range of values ​​is

[0079] Example 5

[0080] Based on Example 1, the step of using the phase difference of each baseline output by the phase comparator, the current scanning angle of the narrow-beam phased array, and the deployed phased array baseline information as inputs to the direction-finding algorithm, and outputting the direction-finding result after calculation and processing, includes the following sub-steps:

[0081] For unambiguous phase period n end The process involves iterating through the data, with each iteration including the following steps:

[0082] a) According to n end The ambiguous phase difference between the current value and the measured baselines Based on the direction-finding formula derived from interferometers The unambiguous phase period n of each baseline is derived by deduction. i And record it;

[0083] b) According to the interferometer direction finding formula Calculate the sine value sinθ of the incoming wave direction for each baseline estimate. i And record it;

[0084] c) Construct the azimuth error vector for all baselines. Calculate the variance var of the azimuth sine error vector;

[0085] After completing the traversal, search for the minimum value var of the variance of the sine error vector of the position in each traversal. min And extract the longest baseline unambiguous phase period n corresponding to it. end According to the interferometer direction finding formula The algorithm ultimately estimates the direction of arrival of the wave.

[0086] Example 6

[0087] Based on Example 4, the value of k ranges from 2 to 5.

[0088] Example 7

[0089] Based on Example 4, the beam scanning angle error δ θ It depends on the antenna characteristics.

[0090] Example 8

[0091] Based on Example 1, the number of narrow-beam phased array antennas arranged in the antenna array is one, and the remaining antennas in the antenna array are conventional antennas.

[0092] Example 9

[0093] Based on Example 1, the arrangement of a narrow-beam phased array in the interferometer antenna array specifically involves replacing the first antenna of the interferometer with a narrow-beam phased array.

[0094] Example 10

[0095] An interferometer direction finding system based on phased array guidance includes an antenna array, a receiver, a phase comparator, and a processor. The antenna array is a linear array, with the first antenna being a narrow-beam phased array and the remaining antennas being conventional antennas. After receiving the antenna signals, the receiver transmits them to the phase comparator. The phase comparator outputs the phase difference of each baseline, the current scanning angle of the narrow-beam phased array, and the baseline information of the deployed phased array. The phase difference of each baseline, the current scanning angle of the narrow-beam phased array, and the baseline information of the deployed phased array output by the phase comparator are used as inputs to the direction finding algorithm. After processing by the processor, the direction finding result is output, thereby completing the interferometer direction finding. The system also includes a method for performing any one of the methods described in Examples 1 to 9.

[0096] The units described in the embodiments of the present invention can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0097] According to one aspect of the present invention, a computer program product or computer program is provided, the computer program product or computer program including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and executes the computer instructions, causing the computer device to perform the methods provided in the various optional implementations described above.

[0098] In another aspect, embodiments of the present invention also provide a computer-readable medium, which may be included in the electronic device described in the above embodiments; or it may exist independently and not assembled into the electronic device. The computer-readable medium carries one or more programs, which, when executed by the electronic device, cause the electronic device to perform the methods described in the above embodiments.

[0099] All parts not covered in this invention are the same as or can be implemented using existing technologies.

[0100] The above technical solution is only one embodiment of the present invention. For those skilled in the art, based on the application methods and principles disclosed in the present invention, it is easy to make various types of improvements or modifications, and not limited to the methods described in the above specific embodiments of the present invention. Therefore, the methods described above are only preferred and are not restrictive.

[0101] In addition to the examples above, other embodiments may be obtained by those skilled in the art based on the above disclosure or by making modifications using knowledge or technology in related fields. The features of each embodiment may be interchanged or replaced. Modifications and changes made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A direction-finding method for an interferometer based on phased array guidance, characterized in that, Including the following steps: A narrow-beam phased array is arranged in the interferometer antenna array; When the radiation source projects a signal from the far field at an angle θ relative to the antenna array and the radiation source is located within the beam currently being scanned by the narrow-beam phased array antenna A1, all antennas of the antenna array receive the radiation source signal. The beam scanning characteristics of the narrow-beam phased array are used to constrain the direction of arrival of the radiation source signal, thereby constraining the longest unambiguous phase period range of the interferometer direction finding algorithm. At this time, the phase difference of each baseline output by the phase comparator, the current scanning angle of the narrow-beam phased array, and the baseline information of the deployed phased array are used as inputs to the direction finding algorithm. After calculation and processing, the direction finding result is output, thus completing the interferometer direction finding. The method of constraining the direction of arrival of the radiation source signal by utilizing the beam scanning characteristics of the narrow-beam phased array antenna, thereby constraining the longest unambiguous phase period range of the interferometer direction finding algorithm, includes the following sub-steps: Based on the current scanning angle of the phased array beam and beam scanning angle error Direction of incoming radiation source signal The traversal is constrained, and the constraint range is... ,in k For the longest baseline D end Corresponding unambiguous phase period n end The multiple of the constraints traversed are system parameters; according to the interferometer direction finding formula... Unambiguous phase corresponding to the longest baseline , and thus n end The range of values ​​is .

2. The interferometer direction finding method based on phased array guidance according to claim 1, characterized in that, The step of arranging a narrow-beam phased array in the interferometer antenna array includes the following sub-steps: According to A1A2, A2A3, ..., A N-1 A N The baseline lengths are respectively d 1. d 2、…、 d N-1 The baseline configuration is an interferometer system antenna array arranged in a linear array; when the interferometer system is powered on, all antennas and corresponding radio frequency channels complete phase correction.

3. The interferometer direction finding method based on phased array guidance according to claim 2, characterized in that, When all antennas receive the far-field projected signal from the radiation source, the following steps are included: Record the beam scanning angle of the narrow-beam phased array antenna A1 at this time. And record the baselines A1A2, A2A3, ..., A at this time. N-1 A N There is a fuzzy phase difference , … ; Then, the basic baselines A1A2, A2A3, ..., A N-1 A N Extend to virtual baselines A1A3, A2A4, ..., A N-2 A N A1A4, A2A5, ..., A N-3 A N …、A1A N At this point, the baseline set is {A1A2, A2A3, ..., A...} N-1 A N A1A3, A2A4, ..., A N-2 A N A1A4, A2A5, ..., A N- 3A N …、A1A N The baseline length of all baselines is calculated based on the fuzzy phase difference between the baseline configuration and the base baseline. and with ambiguous phase difference According to the antenna baseline configuration method, the order of this baseline length and baseline phase difference is the same as that of the baseline set {A1A2, A2A3, ..., A...}. N-1 A N A1A3, A2A4, ..., A N-2 A N A1A4, A2A5, ..., A N- 3A N …、A1A N The order of} is consistent.

4. The interferometer direction finding method based on phased array guidance according to claim 1, characterized in that, The direction-finding algorithm takes the phase difference of each baseline output by the phase comparator, the current scanning angle of the narrow-beam phased array, and the deployed phased array baseline information as inputs, processes them, and outputs the direction-finding result, including the following sub-steps: For unambiguous phase period n end The process involves iterating through the data, with each iteration including the following steps: a) According to n end The ambiguous phase difference between the current value and the measured baselines , … Based on the direction-finding formula derived from interferometers The unambiguous phase period of each baseline can be deduced. n i And record it; b) According to the interferometer direction finding formula Calculate the sine value of the incoming wave direction for each baseline estimate. And record it; c) Construct the azimuth error vector for all baselines. Calculate the variance of the azimuth sine error vector. var ; After completing the traversal, search for the minimum value of the variance of the sine error vector of the position in each traversal. var min And extract the longest baseline unambiguous phase period corresponding to it. n end According to the interferometer direction finding formula The algorithm ultimately estimates the direction of arrival of the wave. .

5. The interferometer direction finding method based on phased array guidance according to claim 1, characterized in that, The k The value range is 2 to 5.

6. The interferometer direction finding method based on phased array guidance according to claim 1, characterized in that, The beam scanning angle error It depends on the antenna characteristics.

7. The interferometer direction finding method based on phased array guidance according to claim 1, characterized in that, The antenna array contains one narrow-beam phased array antenna, while the rest of the antennas are conventional antennas.

8. The interferometer direction finding method based on phased array guidance according to claim 1, characterized in that, The specific method of arranging a narrow-beam phased array in the interferometer antenna array is to replace the first antenna of the interferometer with a narrow-beam phased array.

9. An interferometer direction-finding system based on phased array guidance, characterized in that, It includes an antenna array, a receiver, a phase comparator, and a processor. The antenna array is a linear array, and the first antenna of the antenna array is a narrow-beam phased array, while the remaining antennas are conventional antennas. After receiving the antenna signal, the receiver transmits it to the phase comparator. The phase comparator outputs the phase difference of each baseline, the current scanning angle of the narrow beam phased array, and the baseline information of the deployed phased array. The phase difference of each baseline, the current scanning angle of the narrow beam phased array, and the baseline information of the deployed phased array output by the phase comparator are used as inputs to the direction finding algorithm. After processing by the processor, the direction finding result is output, thereby completing the interferometer direction finding. The system also includes a method for performing the method as described in any one of claims 1 to 8.

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