Terrain discrimination system and method based on multi-beam radar

Abstract

The invention discloses a terrain discrimination system and method based on a multi-beam radar, and mainly solves the problem that existing equipment cannot obtain terrain information below a carrier aircraft when the carrier aircraft encounters severe weather. The system comprises a phased-array antenna system, a transceiver, a signal data processing assembly and a power supply assembly. The transceiver generates a clock reference and transmits the clock reference to the signal data processing component; the signal data processing component generates a baseband signal and beam control data, transmits the baseband signal and the beam control data to the transceiver, and transmits the beam control data to the phased-array antenna system for data analysis; the transceiver processes the baseband signal to generate an excitation signal and radiates the excitation signal to the outside through the phased-array antenna system; the phased-array antenna system receives and processes the echo signals, then transmits the echo signals to the transceiver, down-converts the echo signals to an intermediate frequency band, and then sends the echo signals to the signal data processing assembly for sampling, digital signal processing and height and slope direction calculation to obtain a terrain recognition result. The method can stably and accurately obtain the topographic condition under the severe weather condition, and can be used for measuring the task executed by the aerial carrier.

Description

Technical Field

[0001] The present invention belongs to the field of radar technology, and particularly relates to a terrain identification system, which can be used for measuring a mission performed by a carrier aircraft, providing terrain information below the carrier aircraft, and providing a safe landing environment for the carrier aircraft to be identified. Background Art

[0002] When a rotary-wing aircraft takes off or lands, the rotors will stir up sand or debris, or even form sandstorms, making it difficult for the helicopter to land. When a helicopter takes off or lands in this situation, due to poor visibility and unclear terrain conditions, the pilot's spatial orientation will be reduced to a certain extent, which may lead to safety accidents.

[0003] Helicopters play an irreplaceable role in assault operations, rescuing the wounded and transporting supplies. When helicopters are performing missions, pilots often encounter situations where their vision is obstructed, such as foggy weather. In this case, the pilot's current "situational awareness" is greatly reduced, which may lead to danger or even failure to complete the established mission, greatly affecting the helicopter's mission attendance rate and success rate. Therefore, the need to install a system that helps pilots identify terrain in such complex weather conditions is becoming more urgent.

[0004] Conventional optical sensors and laser sensors can achieve good ground observation results under normal weather conditions, but their strength will decay quickly in bad weather, making it difficult to meet ground observation tasks in complex weather conditions such as sandstorms, night, and fog. Compared with lasers, infrared and visible light, microwave millimeter waves do not have such high resolution, but they have strong penetration ability through smoke and dust and good transmission ability.

[0005] Although conventional radio altimeters have strong penetration capabilities through smoke and dust in severe weather conditions, they can only output single-point altitude information below the carrier aircraft, making it impossible for pilots to make accurate judgments about the terrain.

[0006] Patent document No. 200820028543.4 discloses a digital radio altimeter that uses a single antenna receiving system and can only measure a single-point altitude value. For a carrier aircraft, the altitude measured is the nearest point or the single-point altitude of the strongest signal point. It is insensitive to terrain undulations and cannot provide terrain information below the current carrier aircraft. Summary of the invention

[0007] The purpose of the present invention is to propose a terrain discrimination system and method based on multi-beam radar, so that when a carrier aircraft is flying, it can complete the ground observation task in complex weather conditions such as dust, night, and fog, measure the multi-point height of the carrier aircraft relative to the ground, and output terrain information.

[0008] To achieve the above object, the terrain discrimination system based on multi-beam radar of the present invention includes the following.

[0009] To achieve the above object, the technical solution of the present invention is as follows:

[0010] 1. A terrain discrimination system based on multi-beam radar, comprising a phased array antenna system, a transceiver, a signal data processing component, and a power supply component, characterized in that:

[0011] The phased array antenna system includes an antenna array, a feed network, a beam control module, and a TR module;

[0012] The signal data processing component comprises:

[0013] DA module, used to generate 300MHz±75MHz linear frequency modulation signal, which is transmitted to the transceiver as baseband signal;

[0014] AD module, used for receiving 4-channel intermediate frequency signals from the transceiver and performing AD sampling on them;

[0015] The communication module is used to establish a control communication link with the host computer, generate corresponding working timing and instructions according to the specified working mode configuration, and control various working states of the transceiver;

[0016] The digital signal processing module is used to receive the 4-channel AD intermediate frequency sampling data after sampling by the AD module, and perform digital down-conversion, pulse compression, coherent accumulation, and constant false alarm detection processing;

[0017] The height calculation module is used to perform height calculation, point condensation, and slope and aspect calculation based on the data processed by the digital signal processing module to obtain terrain results.

[0018] Further, the antenna array is bidirectionally connected to the feed network, the feed network is bidirectionally connected to the TR module, and the TR module is unidirectionally connected to the beam control module;

[0019] When transmitting a signal, the TR module receives the beam control information from the beam control module, adjusts the amplitude and phase of the signal from the transceiver, and then transmits it to the antenna array through the feed network;

[0020] When receiving a signal, the antenna array receives the echo signal and sends the echo signal to the TR module through the feeding network. The TR module receives the beam control information from the beam control module, processes the echo signal, and then sends it to the transceiver.

[0021] 2. A method for terrain identification using the above system, characterized by comprising the following steps:

[0022] The signal data processing component generates a linear frequency modulation signal as a baseband signal and beam control data for transmission to the transceiver, and transmits the beam control data to the phased array antenna system for data analysis;

[0023] The transceiver generates a clock reference signal and transmits it to the signal data processing component;

[0024] The transceiver filters, mixes, multiplies and amplifies the baseband signal transmitted by the signal data processing component in sequence, and then transmits it to the phased array antenna system for external radiation and power synthesis in space;

[0025] The phased array antenna system receives the ground echo signal to form and beam, azimuth difference, elevation difference and calibrate the four-channel RF signal, and performs phase adjustment, low-noise amplification and digitally controlled attenuation on the four-channel RF signal before transmitting it to the transceiver;

[0026] The transceiver receives the processed sum beam, azimuth difference, elevation difference and calibration sum four-way RF signals, down-converts them to the intermediate frequency band after de-skewing, forms the calibration sum, sum beam, azimuth difference, elevation difference four-way intermediate frequency signals and sends them to the signal data processing component;

[0027] The signal data processing component performs AD sampling, digital signal processing, height calculation, and slope and aspect calculation on the four intermediate frequency signals from the transceiver to obtain terrain recognition results.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] Firstly, since the present invention adopts a phased array antenna array, the phase shift amount can be analyzed through the beam control module, and the antenna array can be controlled to realize antenna beam scanning, so that the beam width can reach 1° and the angle measurement accuracy can reach 0.15°. Compared with conventional radio altimeters, it can provide more precise multi-point heights below the carrier aircraft.

[0030] Secondly, since the digital signal processing module is provided in the signal data processing component of the present invention, the 4-channel intermediate frequency AD sampling data after sampling by the AD module can be received, and digital down-conversion, pulse compression, coherent accumulation, and constant false alarm detection processing can be performed, thereby improving the distance accuracy and distance resolution; at the same time, since the height calculation module is provided in the data processing component, the height calculation, point trace condensation, and slope and aspect calculation can be performed according to the data processed by the digital signal processing module, so that more detailed terrain results can be obtained;

[0031] Thirdly, since the present invention adopts W-band signals to radiate into space, the signal frequency is high, the wavelength is short, and the signal penetration ability is strong. Compared with the current optical sensors and lidars, the present invention can still receive ground echo signals under severe weather conditions, and after processing, it can obtain effective terrain information under the carrier aircraft, thereby improving the success rate of the carrier aircraft in performing related tasks under severe weather conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a structural block diagram of the system of the present invention;

[0033] Figure 2 It is a principle block diagram of the phased array antenna system in the system of the present invention;

[0034] Figure 3 is a principle block diagram of a transceiver in the system of the present invention;

[0035] Figure 4 It is a principle block diagram of the signal data processing component in the system of the present invention;

[0036] Figure 5 This is a diagram of a 128×128 antenna array in the system of the present invention. DETAILED DESCRIPTION

[0037] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0038] Example 1: Terrain identification system based on multi-beam radar,

[0039] Reference Figure 1 The terrain discrimination system based on the multi-beam radar in this example includes a phased array antenna system 1, a transceiver 2, a signal data processing component 3 and a power supply component 4. Among them: the power supply component 4 is unidirectionally connected to the phased array antenna system 1, the transceiver 2, and the signal data processing component 3, the phased array antenna system 1 is bidirectionally connected to the transceiver 2, the transceiver 2 is bidirectionally connected to the signal data processing component 3, and the signal data processing component 3 is unidirectionally connected to the phased array antenna system 1.

[0040] The power supply component 4 receives external power supply and supplies power to the phased array antenna system 1 , the transceiver 2 , and the signal data processing component 3 .

[0041] The transceiver 2 receives the RF band and beam, azimuth difference, elevation difference, calibration and signal from the phased array antenna system 1 and the beam control data and linear frequency modulation signal from the signal data processing component 3; generates a clock reference, an intermediate frequency band and beam, an azimuth difference, an elevation difference, a calibration and, a W-band excitation signal, a calibration signal, and an instrument synchronization signal; and transmits the clock reference, the intermediate frequency band and beam, the azimuth difference, the elevation difference, the calibration and signal to the data processing component 3, transmits the W-band excitation signal and the calibration signal to the phased array antenna system 1, and outputs the instrument synchronization signal to the outside for testing the instrument synchronization.

[0042] The signal data processing component 3 receives the control information of the host computer and the clock reference, intermediate frequency band and beam, azimuth difference, pitch difference, calibration and signal of the transceiver 2, performs altitude calculation and outputs terrain information to the host computer, generates linear frequency modulation signal and beam control data, and transmits the linear frequency modulation signal to the transceiver 2, and transmits the beam control data to the transceiver 2 and the phased array antenna system 1 respectively.

[0043] In the transmitting state, the phased array antenna system 1 receives the beam control data of the signal processing component 3, completes the amplitude and phase adjustment of the W-band excitation signal and the calibration signal received from the transceiver 2, and forms a transmitting signal to radiate into space.

[0044] In the receiving state, the phased array antenna system 1 receives the beam control data of the signal processing component 3, completes the amplitude and phase adjustment of the received ground echo signal, and forms the RF band and beam, azimuth difference, elevation difference, calibration and signal transmission to the transceiver.

[0045] Reference Figure 2 The phased array antenna system 1 comprises an antenna array 11, a feed network 12, a beam control module 13 and a TR module 14. The antenna array 11 is bidirectionally connected to the feed network 12, the feed network 12 is bidirectionally connected to the TR module 14, and the TR module 14 is unidirectionally connected to the beam control module 13.

[0046] The feeding network 12 includes a power distribution network 121 , a sum-difference network 122 and a calibration network 123 , which are independent of each other and perform their respective functions.

[0047] The beam control module 13 includes a beam control code operation submodule 131, a beam control code storage submodule 132 and a beam control code driving submodule 133. The beam control code operation submodule 131 is unidirectionally connected to the beam control code storage submodule 132, and the beam control code storage submodule 132 is unidirectionally connected to the beam control code driving submodule 133.

[0048] The TR module 14 includes a transmitting submodule 141, a receiving submodule 142 and a transceiver switch 143. The transceiver switch 143 is unidirectionally connected to the transmitting submodule 141 and the receiving submodule 142. The transceiver switch 143 is controlled by the beam control code driving submodule 133 in the beam control module 13 to control the switching of the transceiver state of the TR module 14.

[0049] When transmitting a signal, the transmitting submodule 141 in the TR module 14 is controlled by the beam control code driving submodule 133 in the beam control module 13, and sends the W-band excitation signal and calibration signal from the transceiver 2 to the power distribution network 121 in the feed network 12 after phase shifting, amplification and filtering; the power distribution network 121 in the feed network 12 distributes the amplified W-band excitation signal and calibration signal to the antenna array 11 for transmission into space;

[0050] When receiving signals, the antenna array 11 receives ground echo signals, and forms RF and beam, azimuth difference, elevation difference, calibration and signal through the sum-difference network 122 and calibration network 123 in the feeding network 12, and transmits them to the receiving submodule 142 in the TR module 14. The receiving submodule 142 is controlled by the beam control code driving submodule 133 in the beam control module 13 to perform low-noise amplification and amplitude and phase adjustment on the received signal, and outputs sum beam, elevation difference, azimuth difference, calibration and four-way RF signals, which are transmitted to the transceiver 2.

[0051] Reference Figure 3 The transceiver 2 includes a frequency source module 21, a transmitter 22, a calibration receiver 23, a sum-difference channel receiver 24, and a control module 25, wherein the frequency source module 21 is unidirectionally connected to the transmitter 22, the calibration receiver 23, the sum-difference receiver 24, and the control module 25, and the control module 25 is unidirectionally connected to the transmitter 22, the calibration receiver 23, and the sum-difference receiver 24.

[0052] The frequency source module 21 is used to generate a local oscillator signal, an AD clock reference, a DDS clock reference, a timing clock reference 1, a timing clock reference 2 and an instrument synchronization signal, wherein the local oscillator signal is sent to a transmitter 22, a calibration receiver 23, and a sum and difference channel receiver 24 respectively, the AD clock reference, the DDS clock reference, the timing clock reference 1, and the timing clock reference 2 are sent to a signal data processing component 3, and the instrument synchronization signal is used for synchronization of external test instruments.

[0053] The transmitter 22 receives the baseband signal from the signal data processing component 3, and generates a W-band excitation signal after mixing, filtering, multiplying and amplifying in sequence. The W-band excitation signal is selected by a single-pole double-throw switch controlled by the control module 25 and transmitted to the phased array antenna system 1.

[0054] The calibration receiver 23 receives the radio frequency calibration signal, down-converts it to an intermediate frequency band to form an intermediate frequency signal, and transmits it externally.

[0055] The sum-difference receiver 24 includes a sum receiver, an elevation difference receiver, and an azimuth difference receiver. These three receivers are independent of each other and perform their respective functions. The sum receiver receives the radio frequency sum beam, the elevation difference receiver receives the radio frequency elevation difference, and the azimuth difference receiver receives the radio frequency azimuth difference. These received signals are all down-converted to the intermediate frequency band to form intermediate frequency sum beam, intermediate frequency elevation difference, and intermediate frequency azimuth difference signals and transmit them externally.

[0056] The control module 25 controls the operation switching of the transmitter 22 , the calibration receiver 23 , and the sum-difference receiver 24 , and performs AGC control on the calibration receiver 23 and the sum-difference receiver 24 .

[0057] refer to Figure 4 The signal data processing component 3 includes a DA module 31, an AD module 32, a digital signal processing module 33, a height calculation module 34 and a communication module 35. The AD module is unidirectionally connected to the digital signal processing module 33, the digital signal processing module 33 is unidirectionally connected to the height calculation module 34 and bidirectionally connected to the communication module 35.

[0058] The DA module 31 receives the DDS clock reference of the frequency source module 21 in the transceiver 2 to generate a linear frequency modulation signal of 300 MHz±75 MHz, and transmits it to the transmitter 22 in the transceiver 2 as a baseband signal.

[0059] The AD module 32 receives the intermediate frequency and beam, azimuth difference, elevation difference, calibration and AD sampling processing from the transceiver 2, and transmits the sum beam, azimuth difference, elevation difference, calibration and these four AD sampling data to the digital signal processing module 33.

[0060] The digital signal processing module 33 is controlled by the communication module 35, receives the 4-channel AD intermediate frequency sampling data processed by the AD module 32, performs digital down-conversion, pulse compression, coherent accumulation, and constant false alarm detection, and sends the signal frequency, amplitude, phase and other information to the height solution module 34 and the communication module 35 respectively, and sends the working status information to the communication module 35.

[0061] The height calculation module 34 receives the signal frequency, amplitude, phase and other information processed by the digital signal processing module 33, performs height calculation, point condensation, slope and aspect calculation, outputs the terrain result, and transmits it to the communication module 35;

[0062] The communication module 35 receives the status information of the digital signal processing module 33 and the terrain information of the height calculation module 34 to respectively realize the ARINC429 communication with the host computer and the RS422 communication with the phased array antenna system 1 and the transceiver 2.

[0063] Embodiment 2: Terrain identification method based on multi-beam radar.

[0064] This example uses the above system to perform terrain discrimination, and its implementation includes the following:

[0065] Step 1: Generate and transmit a clock reference signal.

[0066] The frequency source module 21 in the transceiver 2 generates a clock reference signal and transmits it to the signal data processing component 3, and generates a local oscillator signal and transmits it to the transmitter 22, the calibration receiver 23, and the sum-difference receiver 24 respectively;

[0067] Step 2: Generate and transmit linear frequency modulation signals and beam control data.

[0068] The signal data processing component 3 generates a linear frequency modulation signal and beam control data, and transmits the linear frequency modulation signal to the transceiver 2 as a baseband signal, and transmits the beam control data to the phased array antenna system 1 and the transceiver 2. The beam control module 13 in the phased array antenna system 1 parses the beam control data and then transmits it to the TR module 14.

[0069] Step 3: Generate and transmit a W-band excitation signal.

[0070] The transmitter 22 in the transceiver 2 sequentially filters, mixes, multiplies, and amplifies the baseband signal to generate a W-band excitation signal to be transmitted to the TR module 14 in the phased array antenna system 1;

[0071] The TR module 14 adjusts the phase according to the analyzed phase shift amount and sends the W-band excitation signal to the feeding network 12. The power distribution network 121 in the feeding network 12 distributes the power of the W-band excitation signal and sends it to the antenna array 11, which is then radiated outward through the antenna radiation unit and power is synthesized in space.

[0072] Step 4, receive the ground echo signal, form the sum beam, azimuth difference, elevation difference and calibration and RF signal and transmit them.

[0073] 4.1) The antenna array 11 is divided into four quadrants according to a 128×128 array, such as Figure 5 , each area contains 8×8 antenna subarrays, and each subarray contains 8×8 antenna array elements;

[0074] 4.2) With the center of the antenna as the origin, the four centrally symmetrical sub-arrays in each of the four quadrants receive the ground echo signal and pass through the sum-difference network 122 and the calibration network 123 to form the sub-array calibration and W n , and beam R n , pitch difference S n , azimuth difference P n :

[0075]

[0076] 4.3) The following weight vector is calculated based on the beam control data:

[0077] Calibration and weighting vectors:

[0078] and the beam weight vector:

[0079] Pitch difference beam weight vector:

[0080] Azimuth difference beam weight vector: Among them, i and j represent the antenna subarray in the i-th row and j-th column from the origin, and i and j are both less than or equal to 8;

[0081] 4.4) According to the calibration sum, sum beam, elevation difference, and azimuth difference of the known sub-arrays, combined with the corresponding weighting vectors, the following four RF signal outputs are obtained:

[0082] Calibration and:

[0083] And beam:

[0084] Pitch difference:

[0085] Azimuth difference: Where T represents transpose;

[0086] 4.4) The four RF signals of calibration sum, sum beam, elevation difference and azimuth difference are transmitted to transceiver 2.

[0087] Step 5, de-skew the sum beam, azimuth difference, elevation difference, calibration and RF signals, and down-convert them to intermediate frequencies to form four intermediate frequency signals of the sum beam, azimuth difference, elevation difference, calibration and transmit them.

[0088] After receiving the four-way RF signal and beam, azimuth difference, elevation difference and calibration, the TR module 14 performs phase adjustment, low noise amplification and digital control attenuation on the four-way RF signal according to the phase shift and attenuation analyzed by the beam control module 13, and then transmits them to the transceiver 2;

[0089] The calibration receiver 23 and the sum-difference receiver 24 in the transceiver 2 respectively receive the calibration and RF signals after the above processing and the sum beam, azimuth difference, and elevation difference RF signals, and down-convert them to the intermediate frequency band after de-skewing processing to form four intermediate frequency signals of calibration sum, sum beam, azimuth difference, and elevation difference, which are sent to the signal data processing component 3.

[0090] Step 6: After sampling the sum beam, azimuth difference, pitch difference, calibration and intermediate frequency signals, digital signal processing and height, slope and aspect calculation are performed to output the terrain information results.

[0091] The AD module 32 in the signal data processing component 3 performs AD sampling processing on the 4 intermediate frequency signals from the transceiver 2, and the sampled data is output to the digital signal processing module 34 for digital down-conversion, pulse compression, coherent accumulation and constant false alarm detection processing, and then the digital signal processing result is divided into two paths, one is sent to the communication module 33 to generate beam control data and send it to the phased array antenna system 1 and the transceiver 2, and the other is sent to the height calculation module 34 to perform ground multi-point height calculation and point trace condensation, and use the multi-point height information to calculate the slope and slope direction to obtain the terrain recognition result, which is implemented as follows:

[0092] 6.1) The signal data processing component performs AD sampling on the intermediate frequency signal from the transceiver, performs digital down-conversion after sampling, removes the carrier frequency signal, retains the frequency modulation signal, and performs extraction and digital filtering on it;

[0093] 6.2) Perform frequency calculation on the filtered signal to calculate the multi-point height information, and convert the multi-point height information to the geodetic coordinate system according to the corresponding multi-point angle information and the carrier attitude to calculate the slope and aspect:

[0094] 6.3) Given the height information of three adjacent points (x0, y0, z0), (x1, y1, z1), (x2, y2, z2), according to the plane equation ax+by+cz=1, generate the following equations:

[0095]

[0096] 6.4) By solving the equations, we can get the coefficients a, b, c, where a is the coefficient of the x-axis of the tangent plane, b is the coefficient of the y-axis of the tangent plane, and c is the coefficient of the z-axis of the tangent plane;

[0097] 6.5) Calculate the slope θ and slope aspect β based on coefficients a, b, c:

[0098]

[0099] 6.6) Use the two important indicators of slope θ and slope aspect β to determine the terrain status.

[0100] The above descriptions are only two specific examples of the present invention and do not constitute any limitation to the present invention. Obviously, for professionals in this field, after understanding the content and principles of the present invention, it is possible to make various modifications and changes in form and details without departing from the principles and structures of the present invention, such as the increase and decrease of antenna array units, the allocation of sub-arrays and array elements, and the excitation signal can also be changed in addition to the method described in this example, but these modifications and changes based on the ideas of the present invention are still within the scope of protection of the claims of the present invention.

Claims

1. A terrain discrimination system and method based on multi-beam radar, comprising a phased array antenna system (1), a transceiver (2), a signal data processing component (3), and a power supply component (4), characterized in that: The phased array antenna system (1) comprises an antenna array (11), a feed network (12), a beam control module (13), and a TR module (14); The signal data processing component (3) comprises: A DA module (31) is used to generate a 300 MHz ± 75 MHz linear frequency modulation signal and transmit it to the transceiver (2) as a baseband signal; An AD module (32) is used to receive four intermediate frequency signals from the transceiver (2) and perform AD sampling on them; A communication module (33) is used to establish a control communication link with a host computer, generate corresponding working sequences and instructions according to a specified working mode configuration, and control various working states of the phased array antenna system (1) and the transceiver (2); A digital signal processing module (34) is used to receive 4 channels of AD intermediate frequency sampling data sampled by the AD module (32), and perform digital down-conversion, pulse compression, coherent accumulation, and constant false alarm detection processing; The height calculation module (35) is used to perform height calculation, point condensation, and slope and aspect calculation based on the data processed by the digital signal processing module, and output a terrain result.

2. The system according to claim 1, characterized in that The transceiver (2) comprises a frequency source module (21), a transmitter (22), a calibration receiver (23), a sum-difference receiver (24), and a control module (25), wherein: The frequency source module (21) is used to output a local oscillator signal and various required coherent reference clock signals; The transmitter (22) is used to generate a W-band excitation signal and a calibration signal; The calibration receiver (23) is used for calibrating the transceiver channel; The sum-difference receiver (24) is used to perform de-skewing processing on the echo signal and then down-convert it to an intermediate frequency band; The control module (25) is used to control the operating parameters and timing of the frequency source and transceiver components, and to monitor the voltage, temperature and operating status in real time.

3. The system according to claim 1, characterized in that The feeding network (12) is used for power distribution of W-band excitation signals, formation of sum and difference beams, and calibration of transceiver channels, and comprises a power distribution network (121), a sum and difference network (122), and a calibration network (123); The power distribution network (121) is used to distribute the power of the W-band excitation signal and transmit it to each antenna radiation unit; The sum-difference network (122) is used to synthesize the received signal and output a sum beam signal, an elevation difference beam signal and an azimuth difference signal; The calibration network (123) is used to calibrate the transceiver channel and the antenna to ensure the amplitude consistency of the channel and each antenna array element.

4. The system according to claim 1, characterized in that The beam control module (13) is used for information decoding and controlling the TR module, and comprises a beam control code operation module (131), a beam control code storage module (132) and a beam control code driving module (133); The beam control code operation module (131) is used to perform decoding operation on the beam control code to calculate the phase shift amount and the attenuation amount; The beam control code storage module (132) is used to store the phase shift amount and attenuation amount of the beam; The beam control code driving module (133) drives the TR module (14) to achieve phase shifting and attenuation.

5. The system according to claim 1, characterized in that The TR module (14) is used for signal amplification, phase shifting, filtering and digitally controlled attenuation processing, and comprises a transmitting module (141), a receiving module (142) and a transceiver switch (143); The transmitting module (141) is used to perform phase shifting, high-power amplification and filtering of a W-band excitation signal, and then transmit the W-band excitation signal to the antenna array (11) through a power distribution network (121); The receiving module (142) is used for phase shifting, amplitude limiting, low-noise amplification, digitally controlled attenuation and filtering of the received signal; The transceiver switch (143) is used to control the transceiver conversion of the antenna array (11).

6. The system according to claim 1, characterized in that The antenna array (11) is used for transmitting W-band excitation signals and receiving echo signals, and is bidirectionally connected to a feed network (12), the feed network (12) is bidirectionally connected to a TR module (14), and the TR module (14) is unidirectionally connected to a beam control module (13); When transmitting a signal, the TR module (14) receives the beam control information from the beam control module (13), performs amplitude and phase adjustment on the W-band excitation signal from the transceiver (2), and then transmits the W-band excitation signal to the antenna array (11) through the feed network (12); When receiving a signal, the antenna array (11) receives an echo signal and sends the echo signal to a TR module (14) through a feed network (12). The TR module receives beam control information from a beam control module (13), processes the echo signal, and then sends it to a transceiver (2).

7. The system according to claim 1, characterized in that The power supply module (5) is respectively connected to the phased array antenna system (1), the transceiver (2), and the signal data processing component (3) for supplying power to them.

8. A method for terrain identification using the system of claim 1, characterized in that: These include: The signal data processing component generates a linear frequency modulation signal as a baseband signal and beam control data for transmission to the transceiver, and transmits the beam control data to the phased array antenna system for data analysis; The transceiver generates a clock reference signal and transmits it to the signal data processing component; The transceiver mixes, filters, multiplies and amplifies the baseband signal transmitted by the signal data processing component to generate a W-band excitation signal, which is then transmitted to the phased array antenna system for external radiation and power synthesis in space; The phased array antenna system receives the ground echo signal to form and beam, azimuth difference, elevation difference and calibrate the four-channel RF signal, and performs phase adjustment, low-noise amplification and digitally controlled attenuation on the four-channel RF signal before transmitting it to the transceiver; The transceiver receives the processed sum beam, azimuth difference, elevation difference and calibration sum four-way RF signals, down-converts them to the intermediate frequency band after de-skewing, forms the calibration sum, sum beam, azimuth difference, elevation difference four-way intermediate frequency signals and sends them to the signal data processing component; The signal data processing component performs AD sampling, digital signal processing, height calculation, and slope and aspect calculation on the four intermediate frequency signals from the transceiver to obtain terrain recognition results.

9. The method according to claim 8, characterized in that The phased array antenna system receives ground echo signals, forms sum beams, azimuth differences, elevation differences, calibration and four-way RF signals, and is implemented as follows: The antenna array is divided into four quadrants in a 128×128 array, each of which contains 8×8 antenna subarrays, and each subarray contains 8×8 antenna array elements. Taking the center of the antenna as the origin, the four centrosymmetric subarrays in each of the four quadrants form the subarray calibration and W n , and beam R n , pitch difference S n , azimuth difference T n : IN n =[W 00 ···IN ij ···IN 88 ] R n =[R 00 ···R ij ···R 88 ] S n =[S 00 ···S ij ···S 88 ] T n =[T 00 ···T ij ···T 88 ] The following weight vector is calculated based on the beam steering data: Calibration and weighting vector: D n =[D 00 ···D ij ···D 88 ] and beam weight vector: A n =[A 00 ···A ij ···A 88 ] Pitch difference beam weight vector: B n =[B 00 ···B ij ···B 88 ] Azimuth difference beam weight vector: C n =[C 00 ···C ij ···C 88 ] Among them, i and j represent the antenna subarray in the i-th row and j-th column from the origin, and i and j are both less than or equal to 8; According to the calibration sum, sum beam, elevation difference, and azimuth difference of the known subarrays, combined with the corresponding weighting vectors, the following four RF signal outputs are obtained: Calibration and: And beam: Pitch difference: Azimuth difference: Where T stands for transpose.

10. The method according to claim 8, characterized in that The signal data processing component performs AD sampling, digital signal processing, height calculation, slope and aspect calculation, and outputs terrain results on the four intermediate frequency signals from the transceiver, including the following: 10a) The signal data processing component performs AD sampling on the intermediate frequency signal from the transceiver, performs digital down-conversion after sampling, removes the carrier frequency signal, retains the frequency modulation signal, and performs extraction and digital filtering on it; 10b) Perform frequency calculation on the filtered signal to calculate the multi-point height information, and convert the multi-point height information to the geodetic coordinate system according to the corresponding multi-point angle information and the carrier attitude to calculate the slope and aspect: 10b1) Given the height information of three adjacent points (x0, y0, z0), (x1, y1, z1), (x2, y2, z2), according to the plane equation ax+by+cz=1, generate the following equations: By solving the equations, we can get the coefficients a, b, c, where a is the coefficient of the x-axis of the tangent plane, b is the coefficient of the y-axis of the tangent plane, and c is the coefficient of the z-axis of the tangent plane. 10b2) Calculate the slope θ and slope aspect β based on coefficients a, b, c: 10b3) Use the two important indicators of slope θ and slope aspect β to determine the terrain status.

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