High-speed platform forward-looking array radar air target detection and angle estimation method and device

Abstract

The application provides a high-speed platform forward-looking array radar air target detection and angle estimation method and device. The method first acquires pitch-azimuth multi-channel echo data, and compensates the non-stationary echo data by using prior information to construct a compensation matrix; secondly, the compensated echo data is divided into left and right two groups of azimuth sub-channel data, 3D-Sigma Delta STAP is used for azimuth first step clutter suppression, and adaptive constant false alarm detection is combined to complete azimuth second step air target detection; subsequently, based on the target detection result and the azimuth first step clutter suppression result, single pulse angle measurement is used to realize target azimuth space cone angle estimation; finally, the compensated echo data is divided into upper and lower two groups of pitch sub-channel data, 3D-Sigma Delta STAP is used for pitch direction clutter suppression, and based on the target detection result and the pitch direction clutter suppression result, single pulse angle measurement is used to complete target downward angle estimation. The application realizes reliable target detection and accurate angle estimation under low calculation complexity.

Description

Technical Field

[0001] This invention relates to the field of target detection and angle estimation for high-speed radar platforms, specifically to a method and apparatus for air target detection and angle estimation using a forward-looking array radar for high-speed platforms. Background Technology

[0002] In today's modern warfare, characterized by deep informatization and intelligentization, precision-guided weapons have become a core force influencing the battlefield situation. As a key piece of equipment supporting missiles' autonomous detection capabilities, the performance of missile-borne radar directly affects the weapon system's strike accuracy and battlefield survivability. However, missile-borne radar typically operates in a look-down mode, facing intense ground and sea clutter interference. Furthermore, modern aerial targets exhibit characteristics such as high-speed maneuverability, stealth, and miniaturization, making target signals easily submerged in strong clutter.

[0003] To address this challenge, existing technologies (such as the patent application number CN202510001983.9) propose a forward-looking imaging method for missile-borne forward-looking array radar that simultaneously resists suppression jamming. This method receives echoes from the forward-looking region using an array antenna tangent to the flight path, constructing a three-dimensional echo data processing framework of range-pulse-array. Building upon high-resolution range-axis processing achieved through pulse compression and migration correction, it further establishes the covariance matrix of main lobe interference and noise, and uses an adaptive monopulse algorithm to solve for the target angle and amplitude, thereby generating a two-dimensional forward-looking image.

[0004] Despite advancements in anti-jamming and 3D data sampling, the inherent forward-looking array layout, high operating frequency, and extremely high speed of missile-borne radar still result in significant issues such as clutter Doppler spread, range-Doppler ambiguity, and range dependence. These factors severely weaken clutter suppression, impacting the reliability of target detection and the accuracy of angle estimation. Furthermore, considering the stringent computational resource constraints of missile-borne platforms, traditional high-complexity adaptive algorithms often struggle to meet real-time requirements. Therefore, research on low-computational-complexity airborne forward-looking array radar target detection and angle estimation, building upon the aforementioned 3D processing framework, is of great practical significance for strengthening my country's modern air defense system. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method and apparatus for detecting and estimating airborne targets using a forward-looking array radar for high-speed platforms.

[0006] According to one aspect of the present invention, a method for detecting and estimating the angle of an airborne target using a forward-looking array radar for a high-speed platform includes the following steps:

[0007] Step S1: Acquire the elevation-azimuth multi-channel echo data of the missile-borne forward-looking array radar, and construct a compensation matrix using prior information to compensate for the non-stationary echo data of the missile-borne forward-looking array radar. Step S2: Divide the compensated pitch-azimuth multi-channel echo data into pitch-left azimuth multi-channel data and pitch-right azimuth multi-channel data. Use 3D-ΣΔ STAP to perform azimuth clutter suppression processing on the two sets of data to obtain the two sets of azimuth clutter suppression results. Step S3: Combining the two sets of azimuth clutter suppression results, the adaptive constant false alarm rate (CFAR) detection technology is used to achieve the second step of azimuth air target detection; Step S4: Based on the target detection results and the two sets of azimuth clutter suppression results, the target azimuth spatial cone angle is estimated using single-pulse angle measurement technology; Step S5: Divide the compensated pitch-azimuth multi-channel echo data into upper pitch-azimuth multi-channel data and lower pitch-azimuth multi-channel data. Use 3D-ΣΔ STAP to perform pitch clutter suppression processing on the two sets of data to obtain two sets of pitch clutter suppression results. Step S6: Based on the target detection results and two sets of pitch clutter suppression results, the target downward viewing angle is estimated using single-pulse angle measurement technology.

[0008] Preferably, in step S1, the specific form of the elevation-azimuth multi-channel echo data of the missile-borne forward-looking array radar is as follows:

[0009] In the formula, It is a two-dimensional echo data matrix. This represents the number of distance units, where ... indicates the omitted portion. Indicates the first The echo data vector of each range cell has the following specific form:

[0010] In the formula, Indicates matrix transpose; Number of pitch channels This represents the number of azimuth channels. The number of pulses; Indicates the first The distance unit, the first The first pitching channel, the first One directional passage, the first Echo data of each pulse; For distance fuzzy numbers, For the first The number of clutter blocks contained in a distance cell; For noise; and The first The distance unit, the first The clutter block in the first The echo signal amplitude at the ambiguous distance and the target at the 1st ambiguity distance are similar to those at the 1st ambiguity distance. The amplitude of the echo signal per distance unit, For the first The distance unit, the first The clutter block in the first The expression for the space-time steering vector at the fuzzy distance is:

[0011] In the formula, Indicates the Kronecker product; , , The first The distance unit, the first The clutter block in the first Temporal steering vector, azimuth spatial steering vector, and pitch spatial steering vector at a fuzzy distance; The imaginary unit and , Pi; , , The first The distance unit, the first The clutter block in the first The expressions for the normalized Doppler frequency, azimuth frequency, and elevation frequency at each ambiguity distance are as follows:

[0012]

[0013]

[0014] In the formula, For the speed of the radar platform movement, For the signal wavelength, The pulse repetition frequency, This represents the distance between directional channels. The distance between the tilting and lowering channels. For the first The distance unit in the first... A downward perspective at a vague distance For the first The distance unit, the first The clutter block in the first The azimuth angle at a vague distance; The spacetime steering vector of the target is expressed as:

[0015] In the formula, , , These are the target's time-domain steering vector, azimuth-domain steering vector, and elevation-domain steering vector, respectively. , , Let be the target's normalized Doppler frequency, azimuth frequency, and elevation frequency, respectively, and their expressions are as follows:

[0016]

[0017]

[0018] In the formula, For the target radial velocity, From the perspective of the target location, The azimuth of the target.

[0019] Preferably, in step S1, compensating for the non-stationary echo data of the missile-borne forward-looking array radar specifically includes: A compensation matrix is ​​constructed using prior information, and this matrix is ​​then used to compensate for the non-stationary echo data of the missile-borne forward-looking array radar. The compensation matrix is ​​as follows:

[0020]

[0021]

[0022]

[0023] In the formula, This indicates the generation of a diagonal matrix; Indicates the first The compensation matrix corresponding to each distance cell Indicates the first The time-domain compensation matrix corresponding to each distance cell Indicates the first The azimuth spatial compensation matrix corresponding to each distance cell. Indicates the first The pitch spatial compensation matrix corresponding to each distance cell; , , They represent the first The expressions for the normalized Doppler frequency compensation, azimuth frequency compensation, and elevation frequency compensation corresponding to each range cell are as follows:

[0024]

[0025]

[0026] In the formula, For the first The lower viewpoint corresponding to each distance unit For the first The beam center azimuth angle corresponding to each range cell The lower viewpoint corresponding to the reference distance cell. The azimuth angle of the beam center corresponding to the reference range cell. The viewpoint below the beam center. Let be the azimuth angle of the beam center, and we have:

[0027] In the formula, Indicates the spatial cone angle of the beam center; Then the first The echo data vector after compensation for each range cell is:

[0028] In the formula, Indicates conjugate transpose; Indicates the first Echo data vectors of distance cells; Indicates the first The compensation matrix corresponding to each distance unit; The compensated echo data matrix is ​​as follows:

[0029] In the formula, No. Echo data vector after compensation of each distance cell.

[0030] Preferably, the process described in step S2 specifically includes: Sub-step S2.1: Divide the compensated pitch-azimuth multi-channel echo data into pitch-left azimuth multi-channel data and pitch-right azimuth multi-channel data, which can be specifically expressed as:

[0031]

[0032] In the formula, This indicates pitch-left azimuth multi-channel data. This indicates pitch-right azimuth multi-channel data; This represents the first channel of the pitch-left azimuth multi-channel data. The data vector corresponding to each distance unit This represents the first channel of pitch-right azimuth multi-channel data. The data vector corresponding to each distance unit, and their specific forms are as follows:

[0033]

[0034] In the formula, Indicates the compensation after the first The distance unit, the first The first pitching channel, the first One directional passage, the first Echo data of each pulse; Sub-step S2.2: Convert the two sets of multi-channel data to the post-Doppler domain, the specific expression of which is:

[0035]

[0036] In the formula, This represents pitch-left azimuth multi-channel post-Doppler domain data. This represents pitch-right azimuth multi-channel post-Doppler domain data; , These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The data vector corresponding to the first distance cell, and the data corresponding to the first elevation-right azimuth multi-channel post-Doppler domain data in the first distance cell. The data vector of each distance cell has the following specific expression:

[0037]

[0038] In the formula, Represents the impulse-dimensional Fourier transform. Indicates the first The distance unit, the first The first pitching channel, the first One directional passage, the first Post-Doppler domain data of one Doppler unit; Sub-step S2.3: Based on the two sets of post-Doppler domain data, construct a data vector, the specific expression of which is:

[0039]

[0040]

[0041]

[0042] In the formula, This indicates the first [database] constructed based on pitch-left azimuth multi-channel post-Doppler domain data. The distance unit, the first The data vector corresponding to each Doppler unit This indicates the first [database] constructed based on pitch-right azimuth multi-channel post-Doppler domain data. The distance unit, the first Data vectors corresponding to each Doppler unit; This represents the first [unclear] of the pitch-left azimuth multi-channel post-Doppler domain data. The distance unit, the first The sum-azimuth-elevation difference data vector corresponding to each Doppler cell This represents the first [unclear] of the pitch-left azimuth multi-channel post-Doppler domain data. The distance unit, the first The sum-azimuth-elevation difference data vector corresponding to each Doppler cell; , , These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first Data for each Doppler cell, including azimuth channel data, pitch channel data, and so on. , , These represent the first and second lines of the pitch-right azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The specific expressions for the sum-channel data, azimuth channel data, and elevation channel data corresponding to each Doppler element are as follows:

[0043]

[0044]

[0045]

[0046]

[0047]

[0048] Sub-step S2.4: Calculate the corresponding clutter suppression weights using the constructed data vectors. The expression for the clutter suppression weights is:

[0049]

[0050] In the formula, Inverting a matrix; , These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The clutter suppression weight corresponding to the first Doppler cell, the first Doppler domain data of the elevation-right azimuth multi-channel post-Doppler domain data. Clutter suppression weights corresponding to each Doppler unit; , These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The clutter covariance matrix corresponding to the first Doppler cell, and the first Doppler domain data of the elevation-right azimuth multi-channel data. The clutter covariance matrix corresponding to each Doppler cell is specifically expressed as follows:

[0051]

[0052] In the formula, This represents the distance to the number of training samples; This indicates the first [database] constructed based on pitch-left azimuth multi-channel post-Doppler domain data. The distance unit, the first The data vector corresponding to each Doppler unit This indicates the first [database] constructed based on pitch-right azimuth multi-channel post-Doppler domain data. The distance unit, the first Data vectors corresponding to each Doppler unit; The guide vector for 3D-ΣΔ STAP is expressed as follows:

[0053] Sub-step S2.5: Calculate the azimuth clutter suppression result of the first step using the aforementioned clutter suppression weights. The distance unit, the first The clutter suppression results for each Doppler unit are as follows:

[0054]

[0055] In the formula, and These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The azimuth clutter suppression results corresponding to the first Doppler cell and the first Doppler domain data of the elevation-right azimuth multi-channel post-Doppler domain data. The distance unit, the first The azimuth clutter suppression results corresponding to each Doppler element.

[0056] Preferably, in step S3, the second step of azimuth-oriented aerial target detection specifically includes: Sub-step S3.1: Based on the two sets of azimuth clutter suppression results, construct a data vector, the specific expression of which is:

[0057]

[0058] In the formula, The first method is constructed based on two sets of azimuth clutter suppression results. The distance unit, the first Data vectors corresponding to each Doppler unit; The first set represents the results of the two sets of azimuth clutter suppression. The distance unit, the first The sum-azimuth difference data vector corresponding to each Doppler cell; and The first two sets of azimuth clutter suppression results represent the results of the two sets of azimuth clutter suppression. The distance unit, the first The expressions for the sum and difference channel data corresponding to each Doppler unit are as follows:

[0059]

[0060] Sub-step S3.2: Using the constructed data vector, calculate the corresponding adaptive weights, the expression for which is:

[0061] In the formula, The first set represents the results of the two sets of azimuth clutter suppression. The clutter covariance matrix corresponding to each Doppler cell is specifically expressed as follows:

[0062] In the formula, The first method is constructed based on two sets of azimuth clutter suppression results. The distance unit, the first Data vectors corresponding to each Doppler unit;

[0063] The steering vector representing the second-step adaptive constant false alarm rate (CFAR) detection in the azimuth direction is expressed as:

[0064] Sub-step S3.3: Based on the adaptive weights, construct an adaptive constant false alarm rate detector, the specific expression of which is:

[0065] In the formula, Indicates the first The distance unit, the first The adaptive constant false alarm rate (CFAR) detection statistic corresponding to each Doppler unit. Indicates the reliable detection threshold. Indicates adaptive weights; When the corresponding distance unit and Doppler unit Detection statistics Not lower than the reliable detection threshold Target detection can be achieved in a timely manner.

[0066] Preferably, in step S4, the target azimuth spatial cone angle estimation specifically includes: Sub-step S4.1: Calculate the azimuth single-pulse ratio based on the target detection results and the two sets of azimuth clutter suppression results. The expression is as follows:

[0067] In the formula, This indicates the azimuth cone angle of the target after echo data compensation; and These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The azimuth clutter suppression results corresponding to the first Doppler cell and the first Doppler domain data of the elevation-right azimuth multi-channel post-Doppler domain data. The distance unit, the first The azimuth clutter suppression results corresponding to each Doppler unit; Sub-step S4.2: Based on the azimuth single-pulse ratio, calculate the estimated value of the target's actual azimuth spatial cone angle:

[0068] In the formula, This represents the azimuth spatial frequency compensation amount within the distance cell of the target. This indicates the azimuth single pulse ratio.

[0069] Preferably, the processing described in step S5 specifically includes: Sub-step S5.1: Divide the compensated pitch-azimuth multi-channel echo data into upper pitch-azimuth multi-channel data and lower pitch-azimuth multi-channel data, which can be specifically expressed as:

[0070]

[0071] In the formula, This indicates pitch-azimuth multi-channel data. This represents pitch-azimuth multi-channel data; This represents the first channel of the pitch-azimuth multi-channel data. The data vector corresponding to each distance unit This represents the first channel of the down-tilt-azimuth multi-channel data. The data vector corresponding to each distance unit, and their specific forms are as follows:

[0072]

[0073] In the formula, Indicates the compensation after the first The distance unit, the first The first pitching channel, the first One directional passage, the first Echo data of each pulse; Sub-step S5.2: Convert the two sets of multi-channel data to the post-Doppler domain, the specific expression of which is:

[0074]

[0075] In the formula, This represents the up-tilt-azimuth multi-channel post-Doppler domain data. This represents down-tilt-azimuth multi-channel post-Doppler domain data; , These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The data vector corresponding to the distance cell, the first data in the down-tilt-azimuth multi-channel post-Doppler domain data. The data vector corresponding to each distance cell has the following specific expression:

[0076]

[0077] In the formula, Represents the impulse-dimensional Fourier transform. Indicates the first The distance unit, the first The first pitching channel, the first One directional passage, the first Post-Doppler domain data of one Doppler unit; Sub-step S5.3: Construct a data vector based on the two sets of post-Doppler domain data, the specific expression of which is:

[0078]

[0079]

[0080]

[0081] In the formula, This indicates the first [database] constructed based on up-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first The data vector corresponding to each Doppler unit This indicates the first [database] constructed based on down-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first Data vectors corresponding to each Doppler unit; This represents the first [level] of the up-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first The sum-azimuth-elevation difference data vector corresponding to each Doppler cell This represents the first [level] of the down-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first The sum-azimuth-elevation difference data vector corresponding to each Doppler cell; , , These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first Data for each Doppler cell, including azimuth channel data, pitch channel data, and so on. , , These represent the first and second lines of the down-tilt-azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The specific expressions for the sum-channel data, azimuth channel data, and elevation channel data corresponding to each Doppler element are as follows:

[0082]

[0083]

[0084]

[0085]

[0086]

[0087] Sub-step S5.4: Calculate the corresponding clutter suppression weights using the constructed data vectors. The expression for the clutter suppression weights is:

[0088]

[0089] In the formula, , These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The clutter suppression weight corresponding to the first Doppler cell, the first Doppler domain data of the down-elevation-azimuth multi-channel post-Doppler domain data. Clutter suppression weights corresponding to each Doppler unit; , These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The clutter covariance matrix corresponding to the first Doppler cell, and the first Doppler domain data of the down-elevation-azimuth multi-channel data. The clutter covariance matrix corresponding to each Doppler cell is specifically expressed as follows:

[0090]

[0091] In the formula, This indicates the first [database] constructed based on up-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first The data vector corresponding to each Doppler unit This indicates the first [database] constructed based on down-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first Data vectors corresponding to each Doppler unit; Sub-step S5.5: Calculate the pitch clutter suppression result using the aforementioned clutter suppression weights. The distance unit, the first The clutter suppression results for each Doppler unit are as follows:

[0092]

[0093] In the formula, and These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The elevation clutter suppression results corresponding to the first Doppler cell and the first Doppler domain data of the down-elevation-azimuth multi-channel post-Doppler domain data. The distance unit, the first The pitch clutter suppression results corresponding to each Doppler element.

[0094] Preferably, in step S6, the target downward view estimation specifically includes: Sub-step S6.1: Calculate the pitch monopulse ratio based on the target detection results and the two sets of pitch clutter suppression results. The expression is as follows:

[0095] In the formula, This indicates the downward viewing angle of the target after echo data compensation; , These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The elevation clutter suppression results corresponding to the first Doppler cell and the first Doppler domain data of the down-elevation-azimuth multi-channel post-Doppler domain data. The distance unit, the first The elevation clutter suppression results corresponding to each Doppler unit; Sub-step S6.2: Based on the pitch-to-single-pulse ratio, calculate the estimated actual downward angle of view of the target:

[0096] In the formula, This represents the pitch spatial frequency compensation amount for the distance cell where the target is located. This indicates the pitch-to-single-pulse ratio.

[0097] According to another aspect of the present invention, a high-speed platform forward-looking array radar air target detection and angle estimation device includes a memory and a processor. The memory stores a computer program that can run on the processor, and the processor runs the computer program to perform the steps of the above-described high-speed platform forward-looking array radar air target detection and angle estimation method.

[0098] Compared with the prior art, the present invention has the following beneficial effects: This invention proposes a method and apparatus for airborne target detection and angle estimation using a high-speed platform forward-looking array radar. This method achieves clutter suppression, reliable target detection, and rapid estimation of the target's azimuth spatial cone angle in the azimuth dimension through step-by-step processing combined with 3D-ΣΔ STAP, adaptive constant false alarm rate (CFAR) detection, and monopulse angle measurement. In the elevation dimension, it combines 3D-ΣΔ STAP and monopulse angle measurement to achieve clutter suppression and rapid estimation of the target's downward viewing angle, thus alleviating the challenge of limited computational resources faced by airborne forward-looking array radars in airborne target detection and angle estimation. Attached Figure Description

[0099] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a flowchart of the high-speed platform forward-looking array radar air target detection and angle estimation method provided in the embodiments of the present invention; Figure 2(a) shows the non-stationary echo range Doppler spectrum of the missile-borne forward-looking array radar provided in the embodiment of the present invention; Figure 2(b) shows the range Doppler spectrum of the missile-borne forward-looking array radar after non-stationary echo compensation provided in the embodiment of the present invention; Figure 3(a) shows the range Doppler spectrum after the first step of clutter suppression in the azimuth direction provided in the embodiment of the present invention; Figure 3(b) shows the azimuth-oriented second-step aerial target detection results provided in this embodiment of the invention; Figure 3(c) shows the range Doppler spectrum after pitch clutter suppression provided in the embodiment of the present invention; Figure 4(a) shows the target azimuth spatial cone angle estimation result provided in the embodiment of the present invention; Figure 4(b) shows the target downward view estimation result provided in the embodiment of the present invention. Detailed Implementation

[0100] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0101] This embodiment provides a method for air target detection and angle estimation using a forward-looking array radar for a high-speed platform, including the following steps: 1) Acquire pitch-azimuth multi-channel echo data of the missile-borne forward-looking array radar, and construct a compensation matrix using prior information to compensate for the non-stationary echo data of the missile-borne forward-looking array radar; 2) Divide the compensated pitch-azimuth multi-channel echo data into pitch-left azimuth multi-channel data and pitch-right azimuth multi-channel data. Use 3D-ΣΔ STAP to perform azimuth clutter suppression on the two sets of data to obtain the azimuth clutter suppression results for the two sets of data. 3) Combining the two sets of azimuth clutter suppression results, adaptive constant false alarm rate (CFAR) detection technology is used to achieve the second step of azimuth air target detection; 4) Based on the target detection results and two sets of azimuth clutter suppression results, the target azimuth spatial cone angle is estimated using single-pulse angle measurement technology; 5) Divide the compensated pitch-azimuth multi-channel echo data into upper pitch-azimuth multi-channel data and lower pitch-azimuth multi-channel data. Use 3D-ΣΔ STAP to perform pitch clutter suppression processing on the two sets of data to obtain two sets of pitch clutter suppression results. 6) Based on the target detection results and two sets of pitch clutter suppression results, the target downward angle estimation is achieved by using single-pulse angle measurement technology.

[0102] The specific form of the elevation-azimuth multi-channel echo data of the missile-borne forward-looking array radar mentioned in step 1) is as follows:

[0103] In the formula, It is a two-dimensional echo data matrix. This represents the number of distance units, where ... indicates the omitted portion. Indicates the first The echo data vector of each range cell has the following specific form:

[0104] In the formula, Indicates matrix transpose; Number of pitch channels This represents the number of azimuth channels. The number of pulses; Indicates the first The distance unit, the first The first pitching channel, the first One directional passage, the first Echo data of each pulse; For distance fuzzy numbers, For the first The number of clutter blocks contained in a distance cell; For noise; and The first The distance unit, the first The clutter block in the first The echo signal amplitude at the ambiguous distance and the target at the 1st ambiguity distance are similar to those at the 1st ambiguity distance. The amplitude of the echo signal per distance unit, For the first The distance unit, the first The clutter block in the first The expression for the space-time steering vector at the fuzzy distance is:

[0105] In the formula, Indicates the Kronecker product; , , The first The distance unit, the first The clutter block in the first Temporal steering vector, azimuth spatial steering vector, and pitch spatial steering vector at a fuzzy distance; The imaginary unit and , Pi; , , The first The distance unit, the first The clutter block in the first The expressions for the normalized Doppler frequency, azimuth frequency, and elevation frequency at each ambiguity distance are as follows:

[0106]

[0107]

[0108] In the formula, For the speed of the radar platform movement, For the signal wavelength, The pulse repetition frequency, This represents the distance between directional channels. The distance between the tilting and lowering channels. For the first The distance unit in the first... A downward perspective at a vague distance For the first The distance unit, the first The clutter block in the first The azimuth angle at a vague distance; The spacetime steering vector of the target is expressed as:

[0109] In the formula, , , These are the target's time-domain steering vector, azimuth-domain steering vector, and elevation-domain steering vector, respectively. , , Let be the target's normalized Doppler frequency, azimuth frequency, and elevation frequency, respectively, and their expressions are as follows:

[0110]

[0111]

[0112] In the formula, For the target radial velocity, From the perspective of the target location, The azimuth of the target.

[0113] Step 1) specifically includes compensating for the non-stationary echo data of the missile-borne forward-looking array radar, which includes: The compensation matrix is ​​constructed using prior information. The compensation matrix is ​​as follows:

[0114]

[0115]

[0116]

[0117] In the formula, This indicates the generation of a diagonal matrix; Indicates the first The compensation matrix corresponding to each distance cell Indicates the first The time-domain compensation matrix corresponding to each distance cell Indicates the first The azimuth spatial compensation matrix corresponding to each distance cell. Indicates the first The pitch spatial compensation matrix corresponding to each distance cell; , , They represent the first The expressions for the normalized Doppler frequency compensation, azimuth frequency compensation, and elevation frequency compensation corresponding to each range cell are as follows:

[0118]

[0119]

[0120] In the formula, For the first The lower viewpoint corresponding to each distance unit For the first The beam center azimuth angle corresponding to each range cell The lower viewpoint corresponding to the reference distance cell. The azimuth angle of the beam center corresponding to the reference range cell. The viewpoint below the beam center. Let be the azimuth angle of the beam center, and we have:

[0121] In the formula, Indicates the spatial cone angle of the beam center; Furthermore, the first The echo data vector after compensation for each range cell is:

[0122] In the formula, Indicates conjugate transpose; Indicates the first Echo data vectors of distance cells; Indicates the first The compensation matrix corresponding to each distance unit; Furthermore, the compensated echo data matrix is ​​as follows:

[0123] In the formula, No. Echo data vector after compensation of each distance cell.

[0124] The processing described in step 2) specifically includes: The compensated pitch-azimuth multi-channel echo data is divided into pitch-left azimuth multi-channel data and pitch-right azimuth multi-channel data, which can be specifically represented as follows:

[0125]

[0126] In the formula, This indicates pitch-left azimuth multi-channel data. This indicates pitch-right azimuth multi-channel data; This represents the first channel of the pitch-left azimuth multi-channel data. The data vector corresponding to each distance unit This represents the first channel of pitch-right azimuth multi-channel data. The data vector corresponding to each distance unit, and their specific forms are as follows:

[0127]

[0128] In the formula, Indicates the compensation after the first The distance unit, the first The first pitching channel, the first One directional passage, the first Echo data of each pulse; Furthermore, the two sets of multi-channel data are converted to the post-Doppler domain, and their specific expressions are as follows:

[0129]

[0130] In the formula, This represents pitch-left azimuth multi-channel post-Doppler domain data. This represents pitch-right azimuth multi-channel post-Doppler domain data; , These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The data vector corresponding to the first distance cell, and the data corresponding to the first elevation-right azimuth multi-channel post-Doppler domain data in the first distance cell. The data vector of each distance cell has the following specific expression:

[0131]

[0132] In the formula, Represents the impulse-dimensional Fourier transform. Indicates the first The distance unit, the first The first pitching channel, the first One directional passage, the first Post-Doppler domain data of one Doppler unit; Furthermore, a data vector is constructed based on the two sets of post-Doppler domain data, and its specific expression is as follows:

[0133]

[0134]

[0135]

[0136] In the formula, This indicates the first [database] constructed based on pitch-left azimuth multi-channel post-Doppler domain data. The distance unit, the first The data vector corresponding to each Doppler unit This indicates the first [database] constructed based on pitch-right azimuth multi-channel post-Doppler domain data. The distance unit, the first Data vectors corresponding to each Doppler unit; This represents the first [unclear] of the pitch-left azimuth multi-channel post-Doppler domain data. The distance unit, the first The sum-azimuth-elevation difference data vector corresponding to each Doppler cell This represents the first [unclear] of the pitch-left azimuth multi-channel post-Doppler domain data. The distance unit, the first The sum-azimuth-elevation difference data vector corresponding to each Doppler cell; , , These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first Data for each Doppler cell, including azimuth channel data, pitch channel data, and so on. , , These represent the first and second lines of the pitch-right azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The specific expressions for the sum-channel data, azimuth channel data, and elevation channel data corresponding to each Doppler element are as follows:

[0137]

[0138]

[0139]

[0140]

[0141]

[0142] Furthermore, the corresponding clutter suppression weights are calculated using the constructed data vectors, and the expression for the clutter suppression weights is as follows:

[0143]

[0144] In the formula, Inverting a matrix; , These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The clutter suppression weight corresponding to the first Doppler cell, the first Doppler domain data of the elevation-right azimuth multi-channel post-Doppler domain data. Clutter suppression weights corresponding to each Doppler unit; , These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The clutter covariance matrix corresponding to the first Doppler cell, and the first Doppler domain data of the elevation-right azimuth multi-channel data. The clutter covariance matrix corresponding to each Doppler cell is specifically expressed as follows:

[0145]

[0146] In the formula, This represents the distance to the number of training samples; This indicates the first [database] constructed based on pitch-left azimuth multi-channel post-Doppler domain data. The distance unit, the first The data vector corresponding to each Doppler unit This indicates the first [database] constructed based on pitch-right azimuth multi-channel post-Doppler domain data. The distance unit, the first Data vectors corresponding to each Doppler unit; The guide vector for 3D-ΣΔ STAP is expressed as follows:

[0147] Furthermore, the clutter suppression result of the first step in the azimuth is calculated using the aforementioned clutter suppression weights. The distance unit, the first The clutter suppression results for each Doppler unit are as follows:

[0148]

[0149] In the formula, and These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The azimuth clutter suppression results corresponding to the first Doppler cell and the first Doppler domain data of the elevation-right azimuth multi-channel post-Doppler domain data. The distance unit, the first The azimuth clutter suppression results corresponding to each Doppler element.

[0150] Step 3) specifically includes the following: Based on the two sets of azimuth clutter suppression results, a data vector is constructed, the specific expression of which is:

[0151]

[0152] In the formula, The first method is constructed based on two sets of azimuth clutter suppression results. The distance unit, the first Data vectors corresponding to each Doppler unit; The first set represents the results of the two sets of azimuth clutter suppression. The distance unit, the first The sum-azimuth difference data vector corresponding to each Doppler cell; and The first two sets of azimuth clutter suppression results represent the results of the two sets of azimuth clutter suppression. The distance unit, the first The expressions for the sum and difference channel data corresponding to each Doppler unit are as follows:

[0153]

[0154] Furthermore, the corresponding adaptive weights are calculated using the constructed data vectors, and the expression for the adaptive weights is:

[0155] In the formula, The first set represents the results of the two sets of azimuth clutter suppression. The clutter covariance matrix corresponding to each Doppler cell is specifically expressed as follows:

[0156] In the formula, The first method is constructed based on two sets of azimuth clutter suppression results. The distance unit, the first Data vectors corresponding to each Doppler unit; The steering vector representing the second-step adaptive constant false alarm rate (CFAR) detection in the azimuth direction is expressed as:

[0157] Furthermore, an adaptive constant false alarm rate (CFAR) detector is constructed based on the adaptive weights, and its specific expression is as follows:

[0158] In the formula, Indicates the first The distance unit, the first The adaptive constant false alarm rate (CFAR) detection statistic corresponding to each Doppler unit. Indicates the reliable detection threshold. Indicates adaptive weights; When the corresponding distance unit and Doppler unit When the detection statistic is not lower than the reliable detection threshold, target detection can be achieved.

[0159] Step 4) specifically includes the estimation of the target azimuth spatial cone angle, which includes: Based on the target detection results and the two sets of azimuth clutter suppression results, the azimuth single pulse ratio is calculated, and its expression is as follows:

[0160] In the formula, This indicates the azimuth cone angle of the target after echo data compensation; and These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The azimuth clutter suppression results corresponding to the first Doppler cell and the first Doppler domain data of the elevation-right azimuth multi-channel post-Doppler domain data. The distance unit, the first The azimuth clutter suppression results corresponding to each Doppler unit; Furthermore, based on the azimuth single-pulse ratio, the estimated value of the target's actual azimuth spatial cone angle is calculated:

[0161] In the formula, This represents the azimuth spatial frequency compensation amount within the distance cell of the target. This indicates the azimuth single pulse ratio.

[0162] The processing described in step 5) specifically includes: The compensated pitch-azimuth multi-channel echo data is divided into upper pitch-azimuth multi-channel data and lower pitch-azimuth multi-channel data, which can be specifically represented as follows:

[0163]

[0164] In the formula, This indicates pitch-azimuth multi-channel data. This represents pitch-azimuth multi-channel data; This represents the first channel of the pitch-azimuth multi-channel data. The data vector corresponding to each distance unit This represents the first channel of the down-tilt-azimuth multi-channel data. The data vector corresponding to each distance unit, and their specific forms are as follows:

[0165]

[0166] In the formula, Indicates the compensation after the first The distance unit, the first The first pitching channel, the first One directional passage, the first Echo data of each pulse; Furthermore, the two sets of multi-channel data are converted to the post-Doppler domain, and their specific expressions are as follows:

[0167]

[0168] In the formula, This represents the up-tilt-azimuth multi-channel post-Doppler domain data. This represents down-tilt-azimuth multi-channel post-Doppler domain data; , These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The data vector corresponding to the distance cell, the first data in the down-tilt-azimuth multi-channel post-Doppler domain data. The data vector corresponding to each distance cell has the following specific expression:

[0169]

[0170] In the formula, Represents the impulse-dimensional Fourier transform. Indicates the first The distance unit, the first The first pitching channel, the first One directional passage, the first Post-Doppler domain data of one Doppler unit; Furthermore, a data vector is constructed based on the two sets of post-Doppler domain data, and its specific expression is as follows:

[0171]

[0172]

[0173]

[0174] In the formula, This indicates the first [database] constructed based on up-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first The data vector corresponding to each Doppler unit This indicates the first [database] constructed based on down-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first Data vectors corresponding to each Doppler unit; This represents the first [level] of the up-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first The sum-azimuth-elevation difference data vector corresponding to each Doppler cell This represents the first [level] of the down-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first The sum-azimuth-elevation difference data vector corresponding to each Doppler cell; , , These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first Data for each Doppler cell, including azimuth channel data, pitch channel data, and so on. , , These represent the first and second lines of the down-tilt-azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The specific expressions for the sum-channel data, azimuth channel data, and elevation channel data corresponding to each Doppler element are as follows:

[0175]

[0176]

[0177]

[0178]

[0179]

[0180] Furthermore, the corresponding clutter suppression weights are calculated using the constructed data vectors, and the expression for the clutter suppression weights is as follows:

[0181]

[0182] In the formula, , These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The clutter suppression weight corresponding to the first Doppler cell, the first Doppler domain data of the down-elevation-azimuth multi-channel post-Doppler domain data. Clutter suppression weights corresponding to each Doppler unit; , These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The clutter covariance matrix corresponding to the first Doppler cell, and the first Doppler domain data of the down-elevation-azimuth multi-channel data. The clutter covariance matrix corresponding to each Doppler cell is specifically expressed as follows:

[0183]

[0184] In the formula, This indicates the first [database] constructed based on up-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first The data vector corresponding to each Doppler unit This indicates the first [database] constructed based on down-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first Data vectors corresponding to each Doppler unit; Furthermore, the pitch clutter suppression result is calculated using the aforementioned clutter suppression weights. The distance unit, the first The clutter suppression results for each Doppler unit are as follows:

[0185]

[0186] In the formula, and These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The elevation clutter suppression results corresponding to the first Doppler cell and the first Doppler domain data of the down-elevation-azimuth multi-channel post-Doppler domain data. The distance unit, the first The pitch clutter suppression results corresponding to each Doppler element.

[0187] Step 6) specifically includes the following: The pitch single-pulse ratio is calculated based on the target detection results and the two sets of pitch clutter suppression results. Its expression is as follows:

[0188] In the formula, This indicates the downward viewing angle of the target after echo data compensation; and These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The elevation clutter suppression results corresponding to the first Doppler cell and the first Doppler domain data of the down-elevation-azimuth multi-channel post-Doppler domain data. The distance unit, the first The elevation clutter suppression results corresponding to each Doppler unit; Furthermore, based on the pitch-to-single-pulse ratio, the estimated actual downward-facing angle of the target is calculated:

[0189] In the formula, This represents the pitch spatial frequency compensation amount for the distance cell where the target is located. This indicates the pitch-to-single-pulse ratio.

[0190] The following describes the specific implementation steps of a high-speed platform forward-looking array radar method for air target detection and angle estimation.

[0191] All implementation steps in this embodiment are performed on the MATLAB 2020b simulation platform, and the simulation experimental parameters are given in Table 1.

[0192] Table 1 Simulation Parameter Table

[0193] like Figure 1 As shown, the implementation steps of this embodiment include: S1: Acquire multi-channel echo data of the missile-borne forward-looking array radar (elevation-azimuth). , , , , These represent the number of pulses, the number of azimuth channels, the number of elevation channels, and the number of range units, respectively. S2: Construct a compensation matrix to compensate for the non-stationary echo data, and obtain... ; S3: Divide the compensated data into pitch-left azimuth and pitch-right azimuth multi-channel data, i.e. , ; S4: 3D-ΣΔ STAP performs the first step of azimuth clutter suppression, resulting in... , ; S5: Utilize adaptive constant false alarm rate (CFAR) detection technology to perform azimuth-oriented second-step aerial target detection, and obtain the target detection results. , , These represent the distance cell where the target is located and the Doppler cell where the moving target is located, respectively. S6: Based on the results of the first and second steps of azimuth measurement, the spatial cone angle of the target azimuth is estimated using single-pulse angle measurement technology. ; S7: Divide the compensated data into up-pitch-azimuth and down-pitch-azimuth multi-channel data, i.e. , ; S8: 3D-ΣΔ STAP is used for pitch clutter suppression, resulting in... , ; S9: Based on the target detection results and pitch clutter suppression results, the target's downward viewing angle is estimated using monopulse angle measurement technology. .

[0194] The processing results of the air target detection and angle estimation method for a high-speed platform forward-looking array radar obtained according to the present invention are shown in Figures 2-4. Figure 2(a) is the range-Doppler spectrum of the non-stationary echo of the missile-borne forward-looking array radar provided in the embodiment of the present invention. It can be seen that the echo data before compensation exhibits obvious non-stationary characteristics and is affected by range ambiguity clutter. Figure 2(b) is the range-Doppler spectrum of the non-stationary echo of the missile-borne forward-looking array radar after compensation provided in the embodiment of the present invention. It can be seen that the non-stationarity of the main lobe of the compensated echo data is effectively suppressed. Figure 3(a) is the range-Doppler spectrum after the first step of clutter suppression in the azimuth direction provided in the embodiment of the present invention. It can be seen that the clutter is effectively suppressed. Figure 3(b) is the target detection result diagram of the second step in the azimuth direction provided in the embodiment of the present invention. It can be seen that the air target can be effectively detected. Figure 3(c) is the range-Doppler spectrum after clutter suppression in the elevation direction provided in the embodiment of the present invention. It can be seen that the clutter is also effectively suppressed. Figures 4(a) and 4(b) are the target azimuth spatial cone angle estimation result and the target downward angle estimation result provided in the embodiment of the present invention, respectively. Each experiment is performed with 200 Monte Carlo experiments and the average of the results is calculated. It can be seen that the present invention can effectively estimate the target azimuth spatial cone angle and downward angle and can obtain high estimation accuracy.

[0195] The present invention also provides a high-speed platform forward-looking array radar air target detection and angle estimation device. The high-speed platform forward-looking array radar air target detection and angle estimation device can be implemented by executing the process steps of the high-speed platform forward-looking array radar air target detection and angle estimation method. That is, those skilled in the art can understand the high-speed platform forward-looking array radar air target detection and angle estimation method as a preferred embodiment of the high-speed platform forward-looking array radar air target detection and angle estimation device.

[0196] Those skilled in the art will understand that, besides implementing the system and its various devices, modules, and units provided by this invention in the form of purely computer-readable program code, the same functions can be achieved entirely through logical programming of the method steps, making the system and its various devices, modules, and units of this invention function in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers. Therefore, the system and its various devices, modules, and units provided by this invention can be considered as a hardware component, and the devices, modules, and units included therein for implementing various functions can also be considered as structures within the hardware component; alternatively, the devices, modules, and units for implementing various functions can be considered as both software modules implementing the method and structures within the hardware component.

[0197] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A method for air target detection and angle estimation using a forward-looking array radar for a high-speed platform, characterized in that, Includes the following steps: Step S1: Acquire the elevation-azimuth multi-channel echo data of the missile-borne forward-looking array radar, and construct a compensation matrix using prior information to compensate for the non-stationary echo data of the missile-borne forward-looking array radar. Step S2: Divide the compensated pitch-azimuth multi-channel echo data into pitch-left azimuth multi-channel data and pitch-right azimuth multi-channel data. Use 3D-ΣΔ STAP to perform azimuth clutter suppression processing on the two sets of data to obtain the two sets of azimuth clutter suppression results. Step S3: Combining the two sets of azimuth clutter suppression results, the adaptive constant false alarm rate (CFAR) detection technology is used to achieve the second step of azimuth air target detection; Step S4: Based on the target detection results and the two sets of azimuth clutter suppression results, the target azimuth spatial cone angle is estimated using single-pulse angle measurement technology; Step S5: Divide the compensated pitch-azimuth multi-channel echo data into upper pitch-azimuth multi-channel data and lower pitch-azimuth multi-channel data. Use 3D-ΣΔ STAP to perform pitch clutter suppression processing on the two sets of data to obtain two sets of pitch clutter suppression results. Step S6: Based on the target detection results and two sets of pitch clutter suppression results, the target downward viewing angle is estimated using single-pulse angle measurement technology.

2. The method according to claim 1, characterized in that, In step S1, the specific form of the elevation-azimuth multi-channel echo data of the missile-borne forward-looking array radar is as follows: In the formula, It is a two-dimensional echo data matrix. This represents the number of distance units, where ... indicates the omitted portion. Indicates the first The echo data vector of each range cell has the following specific form: In the formula, Indicates matrix transpose; Number of pitch channels This represents the number of azimuth channels. The number of pulses; Indicates the first The distance unit, the first The first pitching channel, the first One directional passage, the first Echo data of each pulse; For distance fuzzy numbers, For the first The number of clutter blocks contained in a distance cell; For noise; and The first The distance unit, the first The clutter block in the first The echo signal amplitude at the ambiguous distance and the target at the 1st ambiguity distance are similar to those at the 1st ambiguity distance. The amplitude of the echo signal per distance unit, For the first The distance unit, the first The clutter block in the first The expression for the space-time steering vector at the fuzzy distance is: In the formula, Indicates the Kronecker product; , , The first The distance unit, the first The clutter block in the first Temporal steering vector, azimuth spatial steering vector, and pitch spatial steering vector at a fuzzy distance; The imaginary unit and , Pi; , , The first The distance unit, the first The clutter block in the first The expressions for the normalized Doppler frequency, azimuth frequency, and elevation frequency at each ambiguity distance are as follows: In the formula, For the speed of the radar platform movement, For the signal wavelength, The pulse repetition frequency, This represents the distance between directional channels. The distance between the tilting and lowering channels. For the first The distance unit in the first... A downward perspective at a vague distance For the first The distance unit, the first The clutter block in the first The azimuth angle at a vague distance; The spacetime steering vector of the target is expressed as: In the formula, , , These are the target's time-domain steering vector, azimuth-domain steering vector, and elevation-domain steering vector, respectively. , , Let be the target's normalized Doppler frequency, azimuth frequency, and elevation frequency, respectively, and their expressions are as follows: In the formula, For the target radial velocity, From the perspective of the target location, The azimuth of the target.

3. The method according to claim 2, characterized in that, In step S1, compensation is performed on the non-stationary echo data of the missile-borne forward-looking array radar, specifically including: A compensation matrix is ​​constructed using prior information, and this matrix is ​​then used to compensate for the non-stationary echo data of the missile-borne forward-looking array radar. The compensation matrix is ​​as follows: In the formula, This indicates the generation of a diagonal matrix; Indicates the first The compensation matrix corresponding to each distance cell Indicates the first The time-domain compensation matrix corresponding to each distance cell Indicates the first The azimuth spatial compensation matrix corresponding to each distance cell. Indicates the first The pitch spatial compensation matrix corresponding to each distance cell; , , They represent the first The expressions for the normalized Doppler frequency compensation, azimuth frequency compensation, and elevation frequency compensation corresponding to each range cell are as follows: In the formula, For the first The lower viewpoint corresponding to each distance unit For the first The beam center azimuth angle corresponding to each range cell The lower viewpoint corresponding to the reference distance cell. The azimuth angle of the beam center corresponding to the reference range cell. The viewpoint below the beam center. Let be the azimuth angle of the beam center, and we have: In the formula, Indicates the spatial cone angle of the beam center; Then the first The echo data vector after compensation for each range cell is: In the formula, Indicates conjugate transpose; Indicates the first Echo data vectors of distance cells; Indicates the first The compensation matrix corresponding to each distance unit; The compensated echo data matrix is ​​as follows: In the formula, Indicates the first Echo data vector after compensation of each distance cell.

4. The method according to claim 3, characterized in that, The processing described in step S2 specifically includes: Sub-step S2.1: Divide the compensated pitch-azimuth multi-channel echo data into pitch-left azimuth multi-channel data and pitch-right azimuth multi-channel data, which can be specifically expressed as: In the formula, This indicates pitch-left azimuth multi-channel data. This indicates pitch-right azimuth multi-channel data; This represents the first channel of the pitch-left azimuth multi-channel data. The data vector corresponding to each distance unit This represents the first channel of pitch-right azimuth multi-channel data. The data vector corresponding to each distance unit, and their specific forms are as follows: In the formula, Indicates the compensation after the first The distance unit, the first The first pitching channel, the first One directional passage, the first Echo data of each pulse; Sub-step S2.2: Convert the two sets of multi-channel data to the post-Doppler domain, the specific expression of which is: In the formula, This represents pitch-left azimuth multi-channel post-Doppler domain data. This represents pitch-right azimuth multi-channel post-Doppler domain data; , These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The data vector corresponding to the distance cell, the first [missing information] of the pitch-right azimuth multi-channel post-Doppler domain data. The data vector corresponding to each distance cell has the following specific expression: In the formula, Represents the impulse-dimensional Fourier transform. Indicates the first The distance unit, the first The first pitching channel, the first One directional passage, the first Post-Doppler domain data of one Doppler unit; Sub-step S2.3: Based on the two sets of post-Doppler domain data, construct a data vector, the specific expression of which is: In the formula, This indicates the first [database] constructed based on pitch-left azimuth multi-channel post-Doppler domain data. The distance unit, the first The data vector corresponding to each Doppler unit This indicates the first [database] constructed based on pitch-right azimuth multi-channel post-Doppler domain data. The distance unit, the first Data vectors corresponding to each Doppler unit; This represents the first [unclear] of the pitch-left azimuth multi-channel post-Doppler domain data. The distance unit, the first The sum-azimuth-elevation difference data vector corresponding to each Doppler cell This represents the first [unclear] of the pitch-right azimuth multi-channel post-Doppler domain data. The distance unit, the first The sum-azimuth-elevation difference data vector corresponding to each Doppler cell; , , These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first Data for each Doppler cell, including azimuth channel data, pitch channel data, and so on. , , These represent the first and second lines of the pitch-right azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The specific expressions for the sum-channel data, azimuth channel data, and elevation channel data corresponding to each Doppler element are as follows: Sub-step S2.4: Calculate the corresponding clutter suppression weights using the constructed data vectors. The expression for the clutter suppression weights is: In the formula, Inverting a matrix; , These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The clutter suppression weight corresponding to the first Doppler cell, the first Doppler domain data of the elevation-right azimuth multi-channel post-Doppler domain data. Clutter suppression weights corresponding to each Doppler unit; , These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The clutter covariance matrix corresponding to the first Doppler cell, and the first Doppler domain data of the elevation-right azimuth multi-channel data. The clutter covariance matrix corresponding to each Doppler cell is specifically expressed as follows: In the formula, This represents the distance to the number of training samples; This indicates the first [database] constructed based on pitch-left azimuth multi-channel post-Doppler domain data. The distance unit, the first The data vector corresponding to each Doppler unit This indicates the first [database] constructed based on pitch-right azimuth multi-channel post-Doppler domain data. The distance unit, the first Data vectors corresponding to each Doppler unit; The guide vector for 3D-ΣΔ STAP is expressed as follows: Sub-step S2.5: Calculate the azimuth clutter suppression result of the first step using the aforementioned clutter suppression weights. The distance unit, the first The clutter suppression results for each Doppler unit are as follows: In the formula, and These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The azimuth clutter suppression results corresponding to the first Doppler cell and the first Doppler domain data of the elevation-right azimuth multi-channel post-Doppler domain data. The distance unit, the first The azimuth clutter suppression results corresponding to each Doppler element.

5. The method according to claim 4, characterized in that, In step S3, the second step of azimuth-oriented aerial target detection specifically includes: Sub-step S3.1: Based on the two sets of azimuth clutter suppression results, construct a data vector, the specific expression of which is: In the formula, The first method is constructed based on two sets of azimuth clutter suppression results. The distance unit, the first Data vectors corresponding to each Doppler unit; The first set represents the results of the two sets of azimuth clutter suppression. The distance unit, the first The sum-azimuth difference data vector corresponding to each Doppler cell; and The first two sets of azimuth clutter suppression results represent the results of the two sets of azimuth clutter suppression. The distance unit, the first The expressions for the sum and difference channel data corresponding to each Doppler unit are as follows: Sub-step S3.2: Using the constructed data vector, calculate the corresponding adaptive weights, the expression for which is: In the formula, The first set represents the results of the two sets of azimuth clutter suppression. The clutter covariance matrix corresponding to each Doppler cell is specifically expressed as follows: In the formula, The first method is constructed based on two sets of azimuth clutter suppression results. The distance unit, the first Data vectors corresponding to each Doppler unit; The steering vector representing the second-step adaptive constant false alarm rate (CFAR) detection in the azimuth direction is expressed as: Sub-step S3.3: Based on the adaptive weights, construct an adaptive constant false alarm rate detector, the specific expression of which is: In the formula, Indicates the first The distance unit, the first The adaptive constant false alarm rate (CFAR) detection statistic corresponding to each Doppler unit. Indicates the reliable detection threshold. Indicates adaptive weights; When the corresponding distance unit and Doppler unit Detection statistics Not lower than the reliable detection threshold Target detection can be achieved in a timely manner.

6. The method according to claim 5, characterized in that, In step S4, the target azimuth spatial cone angle estimation specifically includes: Sub-step S4.1: Calculate the azimuth single-pulse ratio based on the target detection results and the two sets of azimuth clutter suppression results. The expression is as follows: In the formula, This indicates the azimuth cone angle of the target after echo data compensation; and These represent the first and second lines of the pitch-left azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The azimuth clutter suppression results corresponding to the first Doppler cell and the first Doppler domain data of the elevation-right azimuth multi-channel post-Doppler domain data. The distance unit, the first The azimuth clutter suppression results corresponding to each Doppler unit; This represents the number of azimuth channels; This refers to the distance between directional channels; Sub-step S4.2: Based on the azimuth single-pulse ratio, calculate the estimated value of the target's actual azimuth spatial cone angle: In the formula, This represents the azimuth spatial frequency compensation amount within the distance cell of the target. This indicates the azimuth single pulse ratio.

7. The method according to claim 6, characterized in that, The processing described in step S5 specifically includes: Sub-step S5.1: Divide the compensated pitch-azimuth multi-channel echo data into upper pitch-azimuth multi-channel data and lower pitch-azimuth multi-channel data, which can be specifically expressed as: In the formula, This indicates pitch-azimuth multi-channel data. This represents pitch-azimuth multi-channel data; This represents the first channel of the pitch-azimuth multi-channel data. The data vector corresponding to each distance unit This represents the first channel of the down-tilt-azimuth multi-channel data. The data vector corresponding to each distance unit, and their specific forms are as follows: In the formula, Indicates the compensation after the first The distance unit, the first The first pitching channel, the first One directional passage, the first Echo data of each pulse; Sub-step S5.2: Convert the two sets of multi-channel data to the post-Doppler domain, the specific expression of which is: In the formula, This represents the up-tilt-azimuth multi-channel post-Doppler domain data. This represents down-tilt-azimuth multi-channel post-Doppler domain data; , These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The data vector corresponding to the distance cell, the first data in the down-tilt-azimuth multi-channel post-Doppler domain data. The data vector corresponding to each distance cell has the following specific expression: In the formula, Represents the impulse-dimensional Fourier transform. Indicates the first The distance unit, the first The first pitching channel, the first One directional passage, the first Post-Doppler domain data of one Doppler unit; Sub-step S5.3: Construct a data vector based on the two sets of post-Doppler domain data, the specific expression of which is: In the formula, This indicates the first [database] constructed based on up-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first The data vector corresponding to each Doppler unit This indicates the first [database] constructed based on down-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first Data vectors corresponding to each Doppler unit; This represents the first [level] of the up-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first The sum-azimuth-elevation difference data vector corresponding to each Doppler cell This represents the first [level] of the down-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first The sum-azimuth-elevation difference data vector corresponding to each Doppler cell; , , These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first Data for each Doppler cell, including azimuth channel data, pitch channel data, and so on. , , These represent the first and second lines of the down-tilt-azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The specific expressions for the sum-channel data, azimuth channel data, and elevation channel data corresponding to each Doppler element are as follows: In the formula, M is the number of pitch channels and N is the number of azimuth channels; Sub-step S5.4: Calculate the corresponding clutter suppression weights using the constructed data vectors. The expression for the clutter suppression weights is: In the formula, , These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The clutter suppression weight corresponding to the first Doppler cell, the first Doppler domain data of the down-elevation-azimuth multi-channel post-Doppler domain data. Clutter suppression weights corresponding to each Doppler unit; This represents the guide vector of 3D-ΣΔ STAP; , These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The clutter covariance matrix corresponding to the first Doppler cell, and the first Doppler domain data of the down-elevation-azimuth multi-channel data. The clutter covariance matrix corresponding to each Doppler cell is specifically expressed as follows: In the formula, This indicates the first [database] constructed based on up-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first The data vector corresponding to each Doppler unit This indicates the first [database] constructed based on down-tilt-azimuth multi-channel post-Doppler domain data. The distance unit, the first Data vectors corresponding to each Doppler unit; Sub-step S5.5: Calculate the pitch clutter suppression result using the aforementioned clutter suppression weights. The distance unit, the first The clutter suppression results for each Doppler unit are as follows: In the formula, and These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The elevation clutter suppression results corresponding to the first Doppler cell and the first Doppler domain data of the down-elevation-azimuth multi-channel post-Doppler domain data. The distance unit, the first The pitch clutter suppression results corresponding to each Doppler element.

8. The method according to claim 7, characterized in that, In step S6, the target downward view estimation includes: Sub-step S6.1: Calculate the pitch monopulse ratio based on the target detection results and the two sets of pitch clutter suppression results. The expression is as follows: In the formula, This indicates the downward viewing angle of the target after echo data compensation; and These represent the first and second lines of the up-tilt-azimuth multi-channel post-Doppler domain data, respectively. The distance unit, the first The elevation clutter suppression results corresponding to the first Doppler cell and the first Doppler domain data of the down-elevation-azimuth multi-channel post-Doppler domain data. The distance unit, the first The elevation clutter suppression result corresponding to each Doppler unit; M is the number of elevation channels; The distance between the pitch and tilt channels; Sub-step S6.2: Based on the pitch-to-single-pulse ratio, calculate the estimated actual downward angle of view of the target: In the formula, This represents the pitch spatial frequency compensation amount for the distance cell where the target is located. This indicates the pitch-to-single-pulse ratio.

9. A high-speed platform forward-looking array radar air target detection and angle estimation device, characterized in that, It includes a memory and a processor, the memory storing a computer program that can run on the processor, the processor running the computer program to perform the steps of the high-speed platform forward-looking array radar air target detection and angle estimation method according to any one of claims 1-8.

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