A method and system for two-dimensional guidance of airborne radar jamming beam pointing

Abstract

The application relates to the technical field of radar countermeasure, and discloses a two-dimensional guidance method and system for airborne radar jamming beam pointing, which comprises the following steps: S1, two-dimensional interferometer direction finding: the arrival azimuth measurement and the arrival elevation angle measurement of a target signal are completed by using a two-dimensional interferometer; S2, jamming beam pointing calculation: according to the measurement results of the arrival azimuth and the arrival elevation angle, the azimuth calculation and the elevation calculation of the radar jamming beam pointing are completed; S3, jamming beam synthesis: according to the results of the azimuth calculation and the elevation calculation of the radar jamming beam pointing, the synthesis of the jamming beam pointing is completed, so that the jamming beam always points to the target signal in the azimuth dimension and the elevation dimension. The application solves the problem of poor accuracy of the jamming beam pointing in the prior art.

Description

Technical Field

[0001] This invention relates to the field of radar countermeasures technology, specifically to a two-dimensional guidance method and system for pointing airborne radar jamming beams. Background Technology

[0002] In airborne radar jamming systems, to ensure the jamming beam is aligned with the target radar, it is necessary to calculate the target radar's real-time azimuth and elevation information, and use this information to guide the direction of the jamming beam. The target radar's azimuth information can be provided by the aircraft's electronic reconnaissance system, which measures the target's arrival azimuth using techniques such as amplitude comparison direction finding, time difference direction finding, or interferometric direction finding. In existing solutions, the elevation information is determined by setting the target radar's estimated elevation angle based on the aircraft's altitude above the ground and the target radar's airborne or ground-based characteristics. Figure 1 The process of guiding the direction of the jamming beam in a conventional radar jamming system is demonstrated.

[0003] 1) The electronic reconnaissance system of this machine obtains the arrival azimuth information of the target radar through direction finding; 2) Determine whether the target is airborne or ground-based, and estimate the target's radar elevation angle according to Table 1; 3) Using the above azimuth and elevation information, the pointing of the interference beam is synthesized.

[0004] Table 1. Target Radar Elevation Angle Prediction Table

[0005] Traditional methods are affected by the estimated elevation angle of the target radar, and cannot guarantee that the jamming beam is accurately pointed at the target radar. Especially for airborne radar targets, since the altitude information of the target radar is lacking, the estimated elevation angle can only be set to a fixed value, which often deviates significantly from the actual elevation angle of the radar. Summary of the Invention

[0006] To overcome the shortcomings of existing technologies, this invention provides a two-dimensional guidance method and system for pointing airborne radar jamming beams, which solves the problems of poor accuracy in pointing jamming beams in existing technologies.

[0007] The technical solution adopted by the present invention to solve the above problems is: A two-dimensional guidance method for pointing an airborne radar jamming beam includes the following steps: S1, Two-dimensional interferometer direction finding: Using a two-dimensional interferometer to measure the azimuth and elevation angles of the target signal; S2, Interference Beam Pointing Calculation: Based on the measurement results of the azimuth and elevation angles of arrival, the azimuth and elevation of the radar interference beam are calculated. S3, Jamming Beamforming: Based on the azimuth and elevation calculations of the radar jamming beam, the jamming beam pointing direction is synthesized to ensure that the jamming beam is always aligned with the target signal in both the azimuth and elevation dimensions.

[0008] As a preferred technical solution, in step S1, the two-dimensional interferometer direction finding uses multiple azimuth and elevation interferometer direction finding antenna elements to form a cross-shaped two-dimensional interferometer direction finding array.

[0009] As a preferred technical solution, in step S1, the azimuth and elevation dimensions share a single antenna.

[0010] As a preferred technical solution, in step S1, each direction finding uses a linear array phase interferometer to achieve azimuth and elevation direction finding through de-ambiguity methods.

[0011] As a preferred technical solution, in step S1, during orientation measurement, elevation orientation measurement is performed first, followed by azimuth orientation measurement.

[0012] As a preferred technical solution, in step S2, if the measured values ​​of the elevation angle and azimuth angle of the target signal are both valid, then the measured values ​​of the elevation angle and azimuth angle of the target signal are used as the azimuth angle and elevation angle of the radar jamming beam, respectively.

[0013] As a preferred technical solution, in step S2, if the azimuth of arrival of the target signal is invalid, the azimuth of the target cannot be confirmed. The direction of the previous radar jamming beam remains unchanged, and the azimuth of arrival of the target signal is measured again in the next jamming beam refresh cycle.

[0014] As a preferred technical solution, in step S2, if the target's arrival elevation angle is invalid but the arrival azimuth angle is valid, then the traditional method is used to set the target radar's estimated elevation angle based on the aircraft's altitude above the ground and the target radar's air or ground attributes, and combine it with the azimuth direction finding value as the azimuth and elevation angles for the radar interference beam pointing.

[0015] As a preferred technical solution, in step S1, a two-dimensional interferometer direction-finding antenna array is constructed using 7 antennas, with each dimension consisting of 4 direction-finding antennas.

[0016] An airborne radar jamming beam pointing two-dimensional guidance system, used to implement the aforementioned airborne radar jamming beam pointing two-dimensional guidance method, includes the following modules connected in sequence: Two-dimensional interferometer direction finding module: used to measure the azimuth and elevation angles of a target signal using a two-dimensional interferometer; Interference beam pointing calculation module: used to calculate the azimuth and elevation of the radar interference beam based on the measurement results of the azimuth and elevation angles of arrival; Jamming beam synthesis module: Used to synthesize the direction of the jamming beam based on the azimuth and elevation calculation results of the radar jamming beam, so that the jamming beam is always aligned with the target signal in the azimuth and elevation dimensions.

[0017] Compared with the prior art, the present invention has the following advantages: (1) The present invention introduces a two-dimensional interferometer direction finding system to measure the azimuth and elevation angles of the target radar and use them as the result of the radar jamming beam pointing, so as to ensure that the jamming beam is aligned with the target signal in real time; (2) In the case of electromagnetic wave signals in the environment that are in the same frequency band as the target radar, the present invention can use the elevation angle measurement results to distinguish the electromagnetic wave signals in the environment from the target radar signals and interfere with the specified radar pulse signals. (3) The present invention is simple, easy to implement, and highly scalable. Attached Figure Description

[0018] Figure 1 This is a diagram showing the pointing and guidance of existing radar jamming beams. Figure 2 A schematic diagram of a two-dimensional guidance system for pointing jamming beams of airborne radar. Figure 3 This is a schematic diagram of the direction-finding section of a two-dimensional interferometer; Figure 4 This is a flowchart of the interference beam pointing calculation section. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0020] Example 1 like Figures 1 to 4 As shown, due to the shortcomings of traditional methods, this method adopts a two-dimensional interferometer direction finding system for azimuth and elevation to directly measure the arrival azimuth and elevation angle of the target signal. The two-dimensional direction finding results are used as the pointing guidance information of the radar jamming beam to improve the accuracy of the elevation dimension guidance information of the radar jamming beam.

[0021] The specific solution is as follows: The airborne radar jamming beam pointing two-dimensional guidance method mainly consists of three parts: a two-dimensional interferometer direction finding part, a jamming beam pointing calculation part, and a jamming beam synthesis part. A detailed block diagram is shown below. Figure 2 As shown.

[0022] The two-dimensional interferometer direction-finding section uses multiple azimuth and elevation interferometer direction-finding antenna elements to form a cross-shaped two-dimensional interferometer direction-finding array, which respectively completes the measurement of the target signal's azimuth angle and elevation angle of arrival, such as... Figure 3 As shown. Each direction finding dimension uses a linear array phase interferometer, and azimuth and elevation direction finding are achieved through deambiguity methods. During direction finding, elevation direction finding is performed first, followed by azimuth direction finding, and the final direction finding results are reported to the interference beam pointing calculation unit.

[0023] The interference beam pointing calculation section calculates the azimuth and elevation of the radar interference beam based on the azimuth and elevation angle measurements reported by the direction finding section of the two-dimensional interferometer. The specific calculation process is as follows: Figure 4 As shown.

[0024] 1) If the measured values ​​of the elevation and azimuth angles of arrival of the target signal are both valid, then the above direction-finding values ​​shall be used as the azimuth and elevation angles of the radar jamming beam. 2) If the azimuth of arrival of the target signal is invalid, the target's azimuth cannot be confirmed. Keep the previous radar jamming beam pointing unchanged and re-measure the azimuth of arrival of the target signal in the next jamming beam refresh cycle. 3) If the target's arrival elevation angle is invalid but the arrival azimuth angle is valid, then the traditional method is used. Based on the aircraft's altitude above the ground and the target radar's air or ground attributes, the estimated elevation angle of the target radar is set, and combined with the azimuth direction finding value, it is used as the azimuth and elevation angles for the radar jamming beam.

[0025] The jamming beam synthesis part uses a phased array beam controller to change the output signal phase of each jamming element based on the calculation results of the jamming beam direction, so that the jamming beam is always aligned with the target signal in the azimuth and elevation dimensions, thus completing the two-dimensional guidance of the radar jamming beam direction.

[0026] Compared with the prior art, the present invention has the following advantages: (1) The present invention introduces a two-dimensional interferometer direction finding system to measure the azimuth and elevation angles of the target radar and use them as the result of the radar jamming beam pointing, so as to ensure that the jamming beam is aligned with the target signal in real time; (2) In the case of electromagnetic wave signals in the environment that are in the same frequency band as the target radar, the present invention can use the elevation angle measurement results to distinguish the electromagnetic wave signals in the environment from the target radar signals and interfere with the specified radar pulse signals. (3) The present invention is simple, easy to implement, and highly scalable.

[0027] Example 2 like Figures 1 to 4As shown, as a further optimization of Embodiment 1, this embodiment also includes the following technical features based on Embodiment 1: Based on this technical method, a two-dimensional interferometer direction-finding antenna array is constructed using seven antennas, with four direction-finding antennas in each dimension, and one antenna shared by the azimuth and elevation dimensions. Analog Devices (ADI) chips and a Xilinx FPGA are used to perform the two-dimensional direction finding operation of the interferometer. A PowerPC is used to calculate the interference beam pointing based on the azimuth and elevation measurements, and the calculation results are sent to a phased array beam controller to complete the interference beam synthesis. The microwave signal radiation input is replaced by an Agilent 8267D multi-functional microwave signal source combined with a self-made horn antenna. A total station is used to calibrate the azimuth and elevation of the microwave signal relative to the direction-finding system. The RF input front-end, down-conversion component, and signal conditioning circuit used in the experiment are all self-made components.

[0028] To verify the pointing effect of the interference beam of this method, the horn antenna was placed at an azimuth angle of 60° and an elevation angle of -10° relative to the system. The RF output of the signal source was turned on, and the direction finding results of the two-dimensional interferometer and the radar interference beam synthesis results were observed, as shown in Table 2.

[0029] Table 2 Test Results

[0030] Therefore, it can be seen that the above-mentioned two-dimensional guidance method for radar jamming beam pointing is effective. Based on the traditional estimation of elevation angle, it prioritizes the use of a two-dimensional interferometer direction finding system to accurately measure the target's arrival azimuth and elevation value, and uses the above reconnaissance results as the basis for calculating the jamming beam pointing, which has strong engineering application value.

[0031] As described above, the present invention can be implemented well.

[0032] 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.

[0033] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Based on the technical essence of the present invention, any simple modifications, equivalent substitutions, and improvements made to the above embodiments within the spirit and principles of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A two-dimensional guidance method for pointing an airborne radar jamming beam, characterized in that, Includes the following steps: S1, Two-dimensional interferometer direction finding: Using a two-dimensional interferometer to measure the azimuth and elevation angles of the target signal; S2, Interference Beam Pointing Calculation: Based on the measurement results of the azimuth and elevation angles of arrival, the azimuth and elevation of the radar interference beam are calculated. S3, Jamming Beamforming: Based on the azimuth and elevation calculation results of the radar jamming beam pointing, the jamming beam pointing is synthesized so that the jamming beam is always aligned with the target signal in the azimuth and elevation dimensions. The calculation of the interference beam pointing includes: If the elevation and azimuth angles of arrival of the target signal are both valid, then the elevation and azimuth angles of arrival are used as the azimuth and elevation angles of the radar jamming beam, respectively. If the azimuth of arrival of the target signal is invalid, the target's azimuth cannot be confirmed. The direction of the previous radar jamming beam remains unchanged, and the target signal azimuth of arrival is measured again in the next jamming beam refresh cycle. If the target's arrival elevation angle is invalid but the arrival azimuth angle is valid, then the traditional method is used to set the target radar's estimated elevation angle based on the aircraft's altitude above the ground and the target radar's air or ground attributes, and combine it with the azimuth direction finding value as the azimuth and elevation angles for the radar jamming beam. The interference beam synthesis is based on the interference beam pointing calculation result. Using a phased array beam controller, the output signal phase of each interference element is changed to complete the final synthesis of the interference beam pointing, so that the interference beam is always aligned with the target signal in the azimuth and elevation dimensions, thus completing the two-dimensional guidance of the radar interference beam pointing.

2. The two-dimensional guidance method for pointing an airborne radar jamming beam according to claim 1, characterized in that, In step S1, the two-dimensional interferometer direction finding uses multiple azimuth and elevation interferometer direction finding antenna elements to form a cross-shaped two-dimensional interferometer direction finding array.

3. The two-dimensional guidance method for pointing an airborne radar jamming beam according to claim 2, characterized in that, In step S1, the azimuth and elevation dimensions share a single antenna.

4. The two-dimensional guidance method for pointing an airborne radar jamming beam according to claim 3, characterized in that, In step S1, each direction finding dimension uses a linear phase interferometer to achieve azimuth and elevation direction finding through de-ambiguity methods.

5. The two-dimensional guidance method for pointing an airborne radar jamming beam according to claim 1, characterized in that, In step S1, during orientation measurement, elevation orientation measurement is performed first, followed by azimuth orientation measurement.

6. A two-dimensional guidance method for pointing an airborne radar jamming beam according to any one of claims 1 to 5, characterized in that, In step S1, a two-dimensional interferometer direction-finding antenna array is constructed using 7 antennas, with each dimension consisting of 4 direction-finding antennas.

7. A two-dimensional guidance system for pointing airborne radar jamming beams, characterized in that, A method for implementing a two-dimensional guidance method for pointing an airborne radar jamming beam as described in any one of claims 1 to 6 comprises the following modules connected in sequence: Two-dimensional interferometer direction finding module: used to measure the azimuth and elevation angles of the target signal using a two-dimensional interferometer; Interference beam pointing calculation module: used to calculate the azimuth and elevation of the radar interference beam based on the measurement results of the azimuth and elevation angles of arrival; Jamming beam synthesis module: Used to synthesize the direction of the jamming beam based on the azimuth and elevation calculation results of the radar jamming beam, so that the jamming beam is always aligned with the target signal in the azimuth and elevation dimensions.

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