High-isolation high-precision directional antenna direction-finding antenna array and implementation method thereof

Abstract

The invention belongs to the technical field of radio direction finding, and particularly relates to a high-isolation high-precision directional antenna direction-finding antenna array and an implementation method thereof. A four-channel direction-finding machine and a cavity are deployed, a correction signal is generated and output to a frequency band selection switch, a receiver records amplitude phase values of four channels, errors of each channel are calculated, and a sample mathematical model is created; calculating an original phase difference between two different positions; correcting the phase difference between the two different positions; arranging all the calculated phase difference values into a matrix according to the frequency and the incident angle, and archiving to obtain a theoretical sample; when direction finding is carried out on a target signal, correlation calculation is carried out on a target signal phase received by a four-channel direction finding machine and sample data, peak value searching is carried out to traverse all possible directions theta, correlation under each theta is calculated, and the maximum value is recorded as the maximum wave incoming direction. The direction finding precision and the real-time response capability of the direction finding equipment are improved, and the continuity and the stability of measurement data are ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of radio direction finding, and in particular relates to a high-isolation and high-precision directional antenna direction finding antenna array and a realization method thereof. Background Art

[0002] At present, the domestic direction-finding antenna is mainly used in ground environments, such as fixed monitoring stations and monitoring vehicles. Regardless of the direction-finding system adopted (such as correlation interferometer direction-finding algorithm, spatial spectrum direction-finding algorithm), its system architecture is mostly to switch antenna channels through matrix switches and share radio frequency channels to achieve the reception and processing of target radio signals.

[0003] However, under the theoretical algorithm model, it is impossible to completely avoid the direction finding error caused by the coupling between antennas. Therefore, the use of high-isolation directional antennas can effectively reduce the shielding effect of structural parts on the signal and reduce the impact of such coupling on the direction finding accuracy. In the scenario where the relative moving speed is 20m / s, especially when it exceeds 40m / s, higher requirements are placed on the real-time response capability of the direction finding equipment.

[0004] Existing devices use algorithms to guide matrix switches to switch channels to select target antennas. The common nine-element three-channel direction-finding antenna array on the market takes 1ms to detect a set of data. When the relative moving speed of the direction-finding target is 50m / s and the phase error between antennas is 30°, this design will affect the direction-finding accuracy.

[0005] Currently, most direction-finding devices on the market cannot achieve high-precision, low-cost direction-finding for high-speed moving targets, and cannot ensure the continuity and stability of the measurement data.

[0006] Therefore, how to improve the existing direction-finding antennas, avoid the direction-finding errors caused by coupling between antennas, reduce the shielding effect of structural parts on the signal, reduce the impact of such coupling on the direction-finding accuracy, improve the real-time response capability of the direction-finding equipment, and ensure the continuity and stability of the measurement data are technical problems that need to be solved urgently. Summary of the invention

[0007] The purpose of the present invention is to provide a high-isolation and high-precision directional antenna direction-finding antenna array and an implementation method thereof, so as to improve the existing direction-finding antenna, avoid the direction-finding error caused by coupling between antennas, reduce the shielding effect of structural parts on signals, reduce the influence of such coupling on direction-finding accuracy, improve the real-time response capability of direction-finding equipment, and ensure the continuity and stability of measurement data.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: In a first aspect, a method for implementing a high-isolation and high-precision directional antenna direction finding antenna array is provided, comprising the following steps: S1: Deploy a four-channel direction finder and cavity consisting of a 2GHz-18GHz direction finding antenna array, a 1GHz-2GHz direction finding antenna array, a 300MHz-1GHz direction finding antenna array, and a 30MHz-300MHz direction finding antenna array; S2: The four-channel direction finder generates a correction signal f 0 The output is sent to the frequency band selection switch. The receiver records the amplitude and phase values ​​of the four channels and calculates the phase error Δ between each channel and the reference channel at this frequency point. ϕ 0, Δ ϕ 1. Δ ϕ 2. Δ ϕ 3. Taking antenna channel 0 as the reference, Δ ϕ 0=0; S3: Create a sample mathematical model based on the phase of an electromagnetic wave versus its spatial position, frequency, and angle of incidence: ϕ= 2πxsinθ / λ+ϕ i ; in, ϕ It is the phase; l is the wavelength of the current signal; i is the angle of incidence; x is the distance difference between the two antennas; ϕ i It's an antenna i At its coordinate position x i The phase delay at i When it is 0, ϕ0 is the initial reference phase of the array element, i∈0, 1, 2, 3; S4: Measuring two different locations x i and x j The frequency between f and the direction of incoming waves i The original phase difference under the condition is expressed as Df ij ( f,θ ), the phase error between any two antennas Df ij ( f,θ ), the specific calculation formula is as follows: Df ij ( f,θ ) = 2πf ( x j −x i ) sinθ / c ; in f is the frequency,c The speed of light is 3*10^8 (m / s), x i Antenna array element i The distance from the origin of the coordinate system, x j Number the antenna elements j The distance from the origin of the coordinate system, i, j ∈0,1,2,3; S5: Calculate the frequency in sequence f ,angle i Δ ϕ 01 , Δ ϕ 02 , Δ ϕ 03 , Δ ϕ 12 , Δ ϕ 13 , Δ ϕ 23 ; where Δ ϕ 01 is the phase difference between antenna 0 and antenna 1, Δ ϕ 02 is the phase difference between antenna 0 and antenna 2, Δ ϕ 03 is the phase difference between antenna 0 and antenna 3, Δ ϕ 12 is the phase difference between antenna 1 and antenna 2, Δ ϕ 13 is the phase difference between antenna 1 and antenna 3, Δ ϕ 23 is the phase difference between antenna 2 and antenna 3; S6: Arrange all the phase difference values ​​calculated in S5 into a matrix according to frequency and incident angle and archive it to obtain a theoretical sample; S7: When finding the direction of the target signal, the phase difference relationship test value between the channels at the frequency point can be obtained by subtracting the phase error in S2 from the target signal received by the four-channel direction finder and then taking the difference between any two phase values. The phase difference test value is correlated with the sample data in step S6, and a peak search is performed to traverse all possible directions. i , i ∈(0,90°), calculate each i The correlation under i for i max , i max This is the direction of the maximum incoming wave.

[0009] Preferably, the 2 GHz-18 GHz direction finding antenna array in step S1 uses four sinusoidal antennas arranged in a non-uniform distribution into a one-dimensional linear array; The 1GHz-2GHz direction-finding antenna array uses four sinusoidal antennas arranged at non-uniform intervals to form a one-dimensional linear array; The 300MHz-1GHz direction-finding antenna array uses four reflective surface dipole antennas, which are evenly spaced and arranged into a one-dimensional linear array; The 30MHz-300MHz direction-finding antenna array uses four directional loop antennas that are evenly spaced and arranged to form a one-dimensional linear array.

[0010] In the second aspect, a high-isolation and high-precision directional antenna direction-finding antenna array is provided, which is used to implement the method for implementing the high-isolation and high-precision directional antenna direction-finding antenna array, including a four-channel direction finder and cavity composed of a 2GHz-18GHz direction-finding antenna array, a 1GHz-2GHz direction-finding antenna array, a 300MHz-1GHz direction-finding antenna array and a 30MHz-300MHz direction-finding antenna array. The total size of the direction-finding antenna array in each frequency band is less than or equal to 1.2 meters, and a directional antenna with a fixed phase center is used as a basic array element for direction finding in each frequency band.

[0011] Preferably, the 1 GHz-2 GHz direction-finding antenna array and the 2 GHz-18 GHz direction-finding antenna array adopt directional antennas based on sinusoidal shapes, the 300 MHz-1 GHz direction-finding antenna array adopts a dipole antenna with a reflecting surface, and the 30 MHz-300 MHz direction-finding antenna array adopts a directional loop antenna.

[0012] Preferably, the 2GHz-18GHz direction-finding antenna array, the 1GHz-2GHz direction-finding antenna array, the 300MHz-1GHz direction-finding antenna array and the 30MHz-300MHz direction-finding antenna array all include an antenna unit and a mounting plate, and the mounting plate is used to accurately locate the antenna position and to perform electromagnetic shielding on subsequent modules.

[0013] Preferably, the four-channel direction finder also includes an amplifier, a frequency band selection switch and a signal processing module, wherein the amplifier is used to perform selectivity and gain adjustment on the signal within the target frequency band, and the frequency band selection switch is used to match the received signal with the corresponding antenna.

[0014] Preferably, the specific process of the signal processing module performing signal processing is as follows: Down-convert the received radio frequency signal to convert it into an intermediate frequency signal; Perform analog-to-digital conversion on the intermediate frequency signal to generate a digital signal; Output a correction signal with the same frequency as the target signal to calculate and compensate for system errors.

[0015] The beneficial effects of the present invention include: The high-isolation and high-precision directional antenna direction-finding antenna array and its implementation method provided by the present invention deploy a four-channel direction finder and a cavity, generate a correction signal and output it to the frequency band selection switch, the receiver records the amplitude and phase values ​​of the four channels, calculates the error of each channel, creates a sample mathematical model; calculates the original phase difference between two different positions; corrects the phase difference between two different positions; arranges all calculated phase difference values ​​into a matrix according to frequency and incident angle and archives them to obtain theoretical samples; when finding the direction of the target signal, the correlation between the target signal phase received by the four-channel direction finder and the sample data is calculated, and a peak search is performed to traverse all possible directions θ, the correlation under each θ is calculated, and the maximum value is recorded as the maximum incoming wave direction. The direction-finding accuracy and real-time response capability of the direction-finding equipment are improved, and the continuity and stability of the measurement data are ensured.

[0016] First, by adopting a non-uniform linear array layout, the space utilization efficiency and installation flexibility are significantly improved compared to the traditional circular array design. The linear array layout can not only be efficiently deployed in a small space, but also has good concealment and adaptability, which is suitable for application requirements in complex environments. Combined with high-gain antenna technology, the system has achieved a qualitative leap in signal capture distance and coverage, further meeting the actual needs of long-distance direction finding.

[0017] Secondly, the antenna design of the present invention not only ensures high gain, but also ensures the stability of the phase center. Compared with traditional antenna designs, the stable phase center not only improves the direction-finding accuracy of the system, but also significantly reduces error accumulation, especially in complex electromagnetic environments. Compared with traditional antennas, this antenna has lower directional pattern side lobes and higher directional gain, and can achieve more accurate target positioning in complex electromagnetic environments. In addition, combined with advanced signal processing algorithms, the system performs well in multi-target simultaneous direction-finding scenarios, further improving anti-interference capabilities and measurement accuracy.

[0018] Thirdly, it adopts efficient multi-channel data acquisition and fast direction finding algorithms. By optimizing the antenna switching mechanism and signal processing flow, the system can complete target positioning and tracking at the millisecond level, significantly improving the response speed and direction finding accuracy, and can meet the application requirements in different scenarios.

[0019] Thirdly, the optimized four-channel four-element antenna linear array design significantly reduces the hardware complexity and cost investment compared to the traditional seven-element three-channel and nine-element three-channel direction-finding arrays. By adopting advanced correlation interferometer lateral algorithms, the system has achieved significant improvements in data acquisition efficiency and direction-finding accuracy. At the same time, the four-channel design can effectively suppress interference signals, further improving the system's anti-interference ability and robustness.

[0020] Finally, it supports multiple continuous IQ (in-phase and quadrature) signal outputs, providing a rich data source for subsequent signal processing and analysis. Through the optimized signal acquisition mechanism, the system can achieve seamless data transmission and processing, significantly improving the stability and reliability of the system. At the same time, it realizes the integrated design of monitoring and direction finding functions, which not only simplifies the operation process, but also improves the integration and scalability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic structural diagram of the 2GHz-18GHz direction-finding antenna array of the present invention.

[0022] Figure 2 It is a schematic structural diagram of a 1 GHz-2 GHz direction-finding antenna array of the present invention.

[0023] Figure 3 It is a schematic structural diagram of the 300MHz-1GHz direction-finding antenna array of the present invention.

[0024] Figure 4 It is a structural schematic diagram of a 20MHz-300MHz direction-finding antenna array of the present invention.

[0025] Figure 5 It is a structural schematic diagram of the high-isolation and high-precision directional antenna direction-finding antenna array of the present invention.

[0026] Figure 6 It is a simulation diagram of the periodic logarithmic antenna isolation of the sinusoidal antenna unit of the present invention at the same distance.

[0027] Figure 7 It is a simulation curve of periodic logarithmic antenna isolation of the sinusoidal antenna unit of the present invention at the same distance.

[0028] Figure 8 It is a simulation diagram of the sinusoidal antenna isolation at a distance of the sinusoidal antenna unit of the present invention.

[0029] Figure 9 The simulation data of the periodic logarithmic antenna isolation of the sinusoidal antenna unit of the present invention at the same distance.

[0030] Figure 10 It is a beam simulation diagram of the sinusoidal antenna unit of the present invention.

[0031] Figure 11 This is the beam 3D simulation result of the sinusoidal antenna unit of the present invention.

[0032] Figure numerals: 1 is a 2GHz-18GHz sinusoidal antenna, 2 is a 1GHz-2GHz sinusoidal antenna, 3 is a 300MHz-1GHz dipole antenna, and 4 is a 20MHz-300MHz loop antenna. DETAILED DESCRIPTION

[0033] The following is combined with Figure 1-Figure 11 The present invention is further described in detail: Example 1 See attached Figure 1 As shown, a method for realizing a high-isolation and high-precision directional antenna direction finding antenna array comprises the following steps: S1: Deploy a four-channel direction finder and cavity consisting of a 2GHz-18GHz direction finding antenna array, a 1GHz-2GHz direction finding antenna array, a 300MHz-1GHz direction finding antenna array, and a 30MHz-300MHz direction finding antenna array; S2: The four-channel direction finder generates a correction signal f 0 The output is sent to the frequency band selection switch. The receiver records the amplitude and phase values ​​of the four channels and calculates the phase error Δ between each channel and the reference channel at this frequency point. ϕ 0, Δ ϕ 1. Δ ϕ 2. Δ ϕ 3. Taking antenna channel 0 as the reference, Δ ϕ 0=0; S3: Create a sample mathematical model based on the phase of an electromagnetic wave versus its spatial position, frequency, and angle of incidence: ϕ= 2πxsinθ / λ+ϕ i ; in, ϕ It is the phase; l is the wavelength of the current signal; i is the angle of incidence; x is the distance difference between the two antennas; ϕ i It's an antenna i At its coordinate position x i The phase delay at i When it is 0, ϕ0 is the initial reference phase of the array element, i∈0, 1, 2, 3; S4: Measuring two different locations x i and x j The frequency between f and the direction of incoming waves i The original phase difference under the condition is expressed as Df ij ( f,θ ), the phase error between any two antennas Df ij ( f,θ ), the specific calculation formula is as follows: Df ij ( f,θ ) = 2πf ( x j −x i ) sinθ / c ; in f is the frequency, c The speed of light is 3*10^8 (m / s), x i Antenna array element i The distance from the origin of the coordinate system, x j Number the antenna elements j The distance from the origin of the coordinate system, i, j ∈0,1,2,3; S5: Calculate the frequency in sequence f ,angle i Δ ϕ 01 , Δ ϕ 02 , Δ ϕ 03 , Δ ϕ 12 , Δ ϕ 13 , Δ ϕ 23 ; Where Δ ϕ 01 is the phase difference between antenna 0 and antenna 1, Δ ϕ 02 is the phase difference between antenna 0 and antenna 2, Δ ϕ 03 is the phase difference between antenna 0 and antenna 3, Δ ϕ 12 is the phase difference between antenna 1 and antenna 2, Δ ϕ 13 is the phase difference between antenna 1 and antenna 3, Δ ϕ 23 is the phase difference between antenna 2 and antenna 3; S6: Arrange all the phase difference values ​​calculated in S5 into a matrix according to frequency and incident angle and archive it to obtain a theoretical sample; S7: When finding the direction of the target signal, the phase difference relationship test value between the channels at the frequency point can be obtained by subtracting the phase error in S2 from the target signal received by the four-channel direction finder and then taking the difference between any two phase values. The phase difference test value is correlated with the sample data in step S6, and a peak search is performed to traverse all possible directions. i , i ∈(0,90°), calculate each i The correlation under i for i max , i max This is the direction of the maximum incoming wave.

[0034] In this embodiment, the 2 GHz-18 GHz direction finding antenna array in step S1 uses four sinusoidal antennas arranged in a non-uniform distribution into a one-dimensional linear array; The 1GHz-2GHz direction-finding antenna array uses four sinusoidal antennas arranged at non-uniform intervals to form a one-dimensional linear array; The 300MHz-1GHz direction-finding antenna array uses four reflective surface dipole antennas, which are evenly spaced and arranged into a one-dimensional linear array; The 30MHz-300MHz direction-finding antenna array uses four directional loop antennas that are evenly spaced and arranged to form a one-dimensional linear array.

[0035] Example 2 On the basis of Example 1, a high-isolation and high-precision directional antenna direction-finding antenna array is used to implement the method for implementing the high-isolation and high-precision directional antenna direction-finding antenna array, including a four-channel direction-finding machine and cavity composed of a 2GHz-18GHz direction-finding antenna array, a 1GHz-2GHz direction-finding antenna array, a 300MHz-1GHz direction-finding antenna array, and a 30MHz-300MHz direction-finding antenna array. The total size of the direction-finding antenna array in each frequency band is less than or equal to 1.2 meters, and a directional antenna with a fixed phase center is used as a basic array element for direction finding in each frequency band. The 2GHz-18GHz direction-finding antenna array, the 1GHz-2GHz direction-finding antenna array, the 300MHz-1GHz direction-finding antenna array, and the 30MHz-300MHz direction-finding antenna array all include antenna units and mounting plates, and the mounting plates are used to accurately locate the antenna position and to electromagnetically shield subsequent modules.

[0036] Example 3 Based on Example 1 or Example 2, see Figure 1 As shown, the 1 GHz-2 GHz direction-finding antenna array and the 2 GHz-18 GHz direction-finding antenna array adopt directional antennas based on sinusoidal shapes, the 300 MHz-1 GHz direction-finding antenna array adopts a dipole antenna with a reflecting surface, and the 30 MHz-300 MHz direction-finding antenna array adopts a directional loop antenna.

[0037] The 2GHz-18GHz direction finding antenna array uses the sinusoidal antenna as the basic unit. Figure 1-Figure 4As shown, four 2GHz-18GHz sinusoidal antennas are arranged in a straight line on the same plane according to a certain distance relationship to ensure that the phase centers are consistent. This frequency band covers a 90-degree direction finding range. According to the requirements of the direction finding angle range and the shortest relationship of the baseline, it is calculated that the shortest baseline requirement for this frequency band is ≤11.77mm, which is much smaller than the antenna size. Therefore, the distance relationship between the antennas is laid out according to the wiring principles of the staggered double baseline and the virtual double baseline, and the size can be limited to 1.3m. The coordinates of the four antennas of the linear array in this frequency band are: A0: 0; A1: 82.5mm; A2: 153.3mm; A3: 1152mm.

[0038] like Figure 2 As shown in the figure, the 1GHz-2GHz direction finding antenna array still uses the sinusoidal antenna as the basic unit. Figure 1-Figure 4 As shown in the figure, four 1GHz-2GHz sinusoidal antennas are arranged on a straight line in the same plane according to a certain distance relationship to ensure the consistency of the phase center. According to the size requirements of the shortest baseline in this frequency band, it is calculated that the shortest distance is much smaller than the antenna size in this frequency band. Therefore, the distance relationship between antennas is laid out according to the wiring principles of staggered double baselines and virtual double baselines, and the size can be limited to 1.1m. The coordinates of the four antennas of the linear array in this frequency band are: A0: 0; A1: 418mm; A2: 840mm; A3: 1050mm.

[0039] like Figure 3 As shown, the 300MHz-1GHz direction-finding antenna array uses a short-circuited loaded dipole reflector structure. The four antennas in this frequency band are arranged on a straight line in the same plane at a certain distance to ensure that the phase centers are consistent. The relative coordinates of the four antennas are: A0: 0; A1: 210mm; A2: 420mm; A3: 630mm.

[0040] like Figure 4 As shown in the figure, the 20MHz-300MHz direction-finding antenna array adopts a cylindrical antenna array element layout. The four antennas in this frequency band are arranged on a straight line in the same plane according to a certain distance relationship to ensure that the phase centers are consistent. The relative coordinates of the four antennas are: A0: 0; A1: 350mm; A2: 700mm; A3: 1050mm.

[0041] Adding a four-channel receiver to the back end of the antenna array can realize radio direction finding in the direction of an angle of 90° (the angle determines the distance relationship between antennas), and its direction finding accuracy can reach 1°RMS, where RMS is 1 times sigma or 1 times standard deviation. The layout of each frequency band is as follows: Figure 1-Figure 4 As shown. Figure 5The antenna array shown is connected to a four-channel direction finder, and there is no need to switch antenna channels when monitoring and finding the target signal. Figure 6-Figure 11 Simulation data of the sinusoidal antenna unit shown, Figure 6 The X in is the X-axis, Figure 8 The X, Y, and Z in the coordinate system respectively represent the X-axis, Y-axis, and Z-axis, and the U, V, and N respectively represent the U-axis, V-axis, and N-axis in another coordinate system.

[0042] The four-channel direction finder also includes an amplifier, a frequency band selection switch and a signal processing module. The amplifier is used to select and adjust the gain of the signal in the target frequency band, and the frequency band selection switch is used to match the received signal with the corresponding antenna.

[0043] The specific process of signal processing by the signal processing module is as follows: down-converting the received RF signal to convert it into an intermediate frequency signal; performing analog-to-digital conversion on the intermediate frequency signal to generate a digital signal; outputting a correction signal with the same frequency as the target signal, and calculating and compensating the system error.

[0044] In summary, the high-isolation and high-precision directional antenna direction-finding antenna array and its implementation method provided by the present invention deploy a four-channel direction finder and a cavity, generate a correction signal and output it to the frequency band selection switch, the receiver records the amplitude and phase values ​​of the four channels, calculates the error of each channel, creates a sample mathematical model; calculates the original phase difference between two different positions; corrects the phase difference between two different positions; arranges all calculated phase difference values ​​into a matrix according to frequency and incident angle and archives them to obtain theoretical samples; when finding the direction of the target signal, the correlation between the target signal phase received by the four-channel direction finder and the sample data is calculated, and a peak search is performed to traverse all possible directions θ, the correlation under each θ is calculated, and the maximum value is recorded as the maximum incoming wave direction. The direction-finding accuracy and real-time response capability of the direction-finding equipment are improved, and the continuity and stability of the measurement data are ensured.

[0045] By adopting a non-uniform linear array layout, compared with the traditional circular array design, the space utilization efficiency and installation flexibility are significantly improved. It can not only be efficiently deployed in a small space, but also has good concealment and adaptability, and is suitable for application requirements in complex environments. The antenna design of the present invention not only ensures high gain, but also ensures the stability of the phase center. Compared with the traditional antenna design, the stable phase center not only improves the direction-finding accuracy of the system, but also significantly reduces error accumulation. Compared with traditional antennas, this antenna has lower directional pattern side lobes and higher directional gain, and can achieve more accurate target positioning in complex electromagnetic environments. Combined with advanced signal processing algorithms, the anti-interference ability and measurement accuracy are further improved.

[0046] By adopting efficient multi-channel data acquisition and fast direction-finding algorithms, and optimizing the antenna switching mechanism and signal processing process, the system can complete target positioning and tracking at the millisecond level, significantly improving the response speed and direction-finding accuracy, and can meet the application requirements in different scenarios. By adopting advanced correlation interferometer lateral algorithms, the system has achieved significant improvements in data acquisition efficiency and direction-finding accuracy. At the same time, the four-channel design can effectively suppress interference signals, further improving the system's anti-interference ability and robustness. It supports multi-channel continuous IQ signal output, providing a rich data source for subsequent signal processing and analysis. Through the optimized signal acquisition mechanism, the system can achieve seamless data transmission and processing, significantly improving the stability and reliability of the system. At the same time, it realizes the integrated design of monitoring and direction-finding functions, which not only simplifies the operation process, but also improves the system's integration and scalability.

Claims

1. A method for realizing a high-isolation and high-precision directional antenna direction finding antenna array, characterized in that: The following steps are involved: S1: Deploy a four-channel direction finder and cavity consisting of a 2GHz-18GHz direction finding antenna array, a 1GHz-2GHz direction finding antenna array, a 300MHz-1GHz direction finding antenna array, and a 30MHz-300MHz direction finding antenna array; S2: The four-channel direction finder generates a correction signal f 0 Output to the frequency band selection switch, the receiver records the amplitude and phase values ​​of the four channels, and calculates the phase error Δ between the frequency point of the correction signal of each channel and the reference channel ϕ 0, Δ ϕ 1. Δ ϕ 2. Δ ϕ 3. Taking antenna channel 0 as the reference, Δ ϕ 0=0; S3: Create a sample mathematical model based on the phase of an electromagnetic wave versus its spatial position, frequency, and angle of incidence: ϕ = 2πxsinθ / λ+ϕ i ； in, ϕ It is the phase; λ is the wavelength of the current signal; θ is the angle of incidence; x is the distance difference between the two antennas; ϕ i It's an antenna i At its coordinate position x i The phase delay at i When it is 0, ϕ0 is the initial reference phase of the array element, i∈0, 1, 2, 3; S4: Measuring two different locations x i and x j The frequency between f and the direction of incoming waves θ The original phase difference under the condition is expressed as Δϕ ij ( f,θ ), the phase error between any two antennas Δϕ ij ( f,θ ), the specific calculation formula is as follows: Δϕ ij ( f,θ ) = 2πf ( x j −x i ) sinθ / c ； in, f is the frequency, c The speed of light is 3*10^8 (m / s), x i Antenna array element i The distance from the origin of the coordinate system, x j Number the antenna elements j The distance from the origin of the coordinate system, i, j ∈0,1,2,3; S5: Calculate the frequency in sequence f ,angle θ Δ ϕ 01 , Δ ϕ 02 , Δ ϕ 03 , Δ ϕ 12 , Δ ϕ 13 , Δ ϕ 23 ; Among them, Δ ϕ 01 is the phase difference between antenna 0 and antenna 1, Δ ϕ 02 is the phase difference between antenna 0 and antenna 2, Δ ϕ 03 is the phase difference between antenna 0 and antenna 3, Δ ϕ 12 is the phase difference between antenna 1 and antenna 2, Δ ϕ 13 is the phase difference between antenna 1 and antenna 3, Δ ϕ 23 is the phase difference between antenna 2 and antenna 3; S6: Arrange all the phase difference values ​​calculated in S5 into a matrix according to frequency and incident angle and archive it to obtain a theoretical sample; S7: When finding the direction of the target signal, the phase difference relationship test value between the channels at its frequency point can be obtained by subtracting the phase error in S2 from the target signal received by the four-channel direction finder and then taking the difference between any two phase values. The phase difference test value is correlated with the sample data in step S6, and a peak search is performed to traverse all possible directions. θ , θ ∈(0,90°), calculate each θ The correlation under θ for θ max , θ max This is the direction of the maximum incoming wave.

2. The method for realizing a high-isolation and high-precision directional antenna direction finding antenna array according to claim 1, characterized in that: The 2 GHz-18 GHz direction finding antenna array in step S1 uses four sinusoidal antennas arranged in a non-uniform distribution into a one-dimensional linear array; The 1GHz-2GHz direction-finding antenna array uses four sinusoidal antennas arranged at non-uniform intervals to form a one-dimensional linear array; The 300MHz-1GHz direction-finding antenna array uses four reflective surface dipole antennas, which are evenly spaced and arranged into a one-dimensional linear array; The 30MHz-300MHz direction-finding antenna array uses four directional loop antennas that are evenly spaced and arranged to form a one-dimensional linear array.

3. A high-isolation and high-precision directional antenna direction-finding antenna array, used to implement a method for implementing a high-isolation and high-precision directional antenna direction-finding antenna array as claimed in any one of claims 1 to 2, characterized in that: It includes a four-channel direction finding machine and cavity consisting of a 2GHz-18GHz direction finding antenna array, a 1GHz-2GHz direction finding antenna array, a 300MHz-1GHz direction finding antenna array, and a 30MHz-300MHz direction finding antenna array. The total size of the direction finding antenna array in each frequency band is less than or equal to 1.2 meters, and a directional antenna with a fixed phase center is used as the basic array element for direction finding in each frequency band.

4. The high-isolation and high-precision directional antenna direction finding antenna array according to claim 3, characterized in that: The 1GHz-2GHz direction-finding antenna array and the 2GHz-18GHz direction-finding antenna array use directional antennas based on a sinusoidal shape, the 300MHz-1GHz direction-finding antenna array uses a dipole antenna with a reflecting surface, and the 30MHz-300MHz direction-finding antenna array uses a directional loop antenna.

5. The high-isolation and high-precision directional antenna direction finding antenna array according to claim 4, characterized in that: The 2GHz-18GHz direction-finding antenna array, the 1GHz-2GHz direction-finding antenna array, the 300MHz-1GHz direction-finding antenna array and the 30MHz-300MHz direction-finding antenna array all include an antenna unit and a mounting plate, and the mounting plate is used to accurately locate the antenna position and to perform electromagnetic shielding on subsequent modules.

6. The high-isolation and high-precision directional antenna direction finding antenna array according to claim 3, characterized in that: The four-channel direction finder also includes an amplifier, a frequency band selection switch and a signal processing module. The amplifier is used to select and adjust the gain of the signal in the target frequency band, and the frequency band selection switch is used to match the received signal with the corresponding antenna.

7. The high-isolation and high-precision directional antenna direction finding antenna array according to claim 6, characterized in that: The specific process of the signal processing module performing signal processing is as follows: Down-convert the received radio frequency signal to convert it into an intermediate frequency signal; Perform analog-to-digital conversion on the intermediate frequency signal to generate a digital signal; Output a correction signal with the same frequency as the target signal to calculate and compensate for system errors.

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