CN116500563A - Semi-physical simulation system of airborne monopulse radar - Google Patents

Abstract

The invention discloses a semi-physical simulation system of an airborne monopulse radar, which mainly solves the problem that the prior art cannot perform full-flow simulation on signal processing from the front end to the rear end of an antenna of the airborne monopulse radar. It comprises the following steps: echo simulation module, receiving module and signal processing module. The echo simulation module simulates and generates radio frequency echo signals of a sum channel, a pitching difference channel and a azimuth difference channel of the monopulse radar when the carrier flies; the receiving module performs down-conversion on the three paths of radio frequency echo signals to obtain three paths of intermediate frequency signals; the signal processing module samples and processes the three paths of intermediate frequency signals and outputs the detection target distance, speed, pitch angle and azimuth angle of the carrier. The invention designs the airborne monopulse radar simulation system by combining software and hardware, has short development period, low cost and high repeated use rate, can realize the full-flow simulation of the signal processing of the airborne monopulse radar from the front end to the rear end of the antenna, and can be used for the design and function verification of the airborne monopulse radar.

Description

A hardware-in-the-loop simulation system for airborne monopulse radar

technical field

The invention belongs to the field of radar technology, in particular to a semi-physical simulation system which can be used for the design and function verification of airborne monopulse radar.

Background technique

In the process of radar development and production, radar performance and indicators need to be tested. The traditional test method is to rely on field tests, that is, to use real targets to provide echo signals to the radar, which requires a lot of manpower, material and financial resources, and lengthens the development cycle. Especially when it comes to airborne products, it is necessary to verify the functional performance through flight tests. The radar performance index test is carried out through the field test, resulting in long development period and high development cost.

The simulation technology combined with software and hardware can simulate the target and use scenarios to provide echo signals for airborne monopulse radar. The radar hardware-in-the-loop simulation system can shorten the radar development cycle and reduce the cost of radar development, and has the advantages of economy, flexibility and reusability. In the development stage, the simulation system can demonstrate the various indicators of the radar and simulate the problems encountered in the actual use of the radar. In the production delivery stage, it can also provide evaluation means for detecting the system performance of the radar.

Through simulation, the radar echo signals of the radar at different attitudes, heights, and speeds of the carrier aircraft can be simulated to verify the design and verification of radar waveforms, antenna patterns and radar signal processing algorithms.

The patent document with application number CN107436755A discloses a "Modeling Method and System for Radar Simulation System", its main purpose is to provide a modeling method for radar simulation system, to simulate and reproduce the working mechanism of radar in different scenarios on the computer and process. The system belongs to software-level simulation, which can carry out theoretical-level simulation verification in the radar design stage, but in the actual test and production stage of the radar, it is necessary to test the hardware indicators of the radar subsystem and the external hardware interface relationship, so this pure software simulation The system cannot be used in the test and production delivery stages of the radar, resulting in the limitation of its application.

Contents of the invention

The purpose of the present invention is to address the deficiencies of the above-mentioned prior art, and propose a kind of airborne monopulse radar hardware-in-the-loop simulation system, to verify and evaluate the overall functional performance of airborne monopulse radar, to meet the radar machine design stage, test stage and Requirements for use in the delivery phase of production.

The technical solutions for realizing the object of the present invention include the following.

1. a hardware-in-the-loop simulation system of airborne monopulse radar, it is characterized in that, comprise back and simulate module 1, receiving module 2 and signal processing module 3, receiving module 2 is respectively with monopulse radar echo simulation module 1 and signal processing Module 3 one-way connection;

The echo simulation module 1 includes a baseband echo submodule 11 and an echo simulation submodule 12, the baseband echo submodule is used to generate a baseband echo signal with target characteristics and aircraft flight attitude, the echo simulation submodule The module is used to up-convert the baseband echo signal, and transmit the up-converted radio frequency signal to the receiving module 2;

The receiving module 2 is used to transmit the intermediate frequency signal after the down-conversion of the radio frequency signal to the signal processing module 3; it includes a sum channel 21, a pitch difference channel 22, an azimuth difference channel 23, a control submodule 24, a frequency source 25 and a power supply Sub-module 26; the three channels are equipped with numerically controlled attenuators, and the attenuation is controlled by the control sub-module; the frequency source generates the synchronization of the high local oscillator and low local oscillator signals and echo analog modules required for down-conversion of the three channels Clock signals for signals and signal processing modules;

The signal processing module 3 includes an ADC submodule 31, a signal processing submodule 32, a storage submodule 33 and a power supply submodule 34, the ADC submodule samples the intermediate frequency signal, and transmits the sampled signal to the signal processing submodule; The signal processing sub-module performs signal processing on the sampling signal; the storage sub-module is used for storing data of the signal processing sub-module and loading chip programs.

Further, the baseband echo sub-module 11 includes a parameter setting unit 111, a transmitting unit 112, an antenna unit 113, a target RCS unit 114, a clutter signal unit 115 and a baseband echo generating unit 116;

The parameter setting unit 111 is used to set the basic parameters of the carrier aircraft, including information such as the flight height of the carrier aircraft, three-axis speed and attitude information, and transmit them to the baseband echo generation unit;

The transmitting unit 112 is used to configure the frequency, power, pulse width, pulse period and modulation mode of the transmitting signal, and transmit it to the baseband echo generating unit;

The antenna unit 113 is used to generate the antenna patterns of the sum channel, the azimuth difference channel and the pitch difference channel, and transmit them to the baseband echo generation unit;

The target RCS unit 114 is used to set the number of targets and RCS characteristics, and transmit them to the baseband echo generation unit;

The clutter signal unit 115 is used to set the clutter signal model and clutter power, and transmit them to the baseband echo generation unit;

The baseband echo generation unit 116 is configured to generate baseband echo data of the sum channel, the azimuth difference channel and the elevation difference channel.

Further, the echo simulation sub-module 12 includes a signal storage unit 121, an analog signal generation unit 122 and an up-conversion unit 123;

The signal storage unit 121 is configured to store the generated baseband echo data;

The analog signal generation unit 122 is used to convert the stored baseband echo data into an analog signal and output it to the up-conversion unit;

The up-conversion unit 123 is used for up-converting the generated analog signal to a radio frequency band.

Further, the control submodule 24 includes a communication unit 241 and a control unit 242;

The communication unit 241 is configured to receive control information from the signal processing module, and transmit the received information to the control unit;

The control unit 242 is used to transmit the control signal to the digitally controlled attenuators of the three channels.

Further, the ADC submodule 31 includes a sum channel unit 311, an azimuth difference channel unit 312, and an elevation difference channel unit 313;

The sum channel unit 311 is configured to perform ADC sampling on the sum channel intermediate frequency signal, and transmit the sampled signal to the signal processing submodule;

The pitch difference channel unit 312 is used to perform ADC sampling on the intermediate frequency signal of the pitch difference channel, and transmit the sampled signal to the signal processing submodule;

The azimuth difference channel unit 313 is used to perform ADC sampling on the intermediate frequency signal of the azimuth difference channel, and transmit the sampled signal to the signal processing sub-module.

Further, the signal processing sub-module 32 includes a signal processing unit 321, a data processing unit 322 and a communication unit 323;

The signal processing unit 321 is used to implement radar signal processing related algorithms, and transmit the processed data to the data processing unit;

The data processing unit 322 is used to implement algorithms related to radar data processing;

The communication unit 323 is used for communicating with the receiving module and outputting the simulation result of the system.

2. a kind of method utilizing above-mentioned system to carry out simulation to airborne monopulse radar, it is characterized in that, realizes as follows:

Initial parameters are set in the baseband echo sub-module 11 of the radar echo simulation module 1, and the three-way baseband echo data of the sum channel, the pitch difference channel and the azimuth difference channel of the monopulse radar are simulated to be produced when the aircraft is flying;

Transmit the three-way baseband echo data to the echo simulation sub-module 12 to generate a radio frequency echo signal, and output it to the receiving module 2;

The receiving module 2 performs down-conversion processing on the three-way radio frequency echo signals to obtain three-way intermediate frequency signals, and transmits them to the signal processing module 3;

The signal processing module 3 performs sampling and signal processing on the three-way intermediate frequency signals sequentially through its ADC submodule 31 and signal processing submodule 32, and outputs the detection target distance, speed, pitch angle and azimuth angle of the carrier aircraft, so as to realize the detection of the airborne monopulse The whole process simulation of radar from antenna front-end to back-end signal processing.

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

First, the present invention can complete different functions due to being provided with different functional units in the echo simulation module 1, that is, through the parameter setting unit 111 to simulate the flying height, speed, attitude information and the flight situation of the carrier aircraft; The transmitting unit 112 performs the simulation verification of the radar transmitter; the antenna unit 113 carries out the simulation verification of the radar antenna pattern; the target RCS unit 114 simulates the RCS characteristics and quantity of the target; not only reduces the design and verification workload of the radar transmitter and antenna , shorten the development cycle, and can reduce the time and cost of flight test and field test by simulating the flight situation of the carrier aircraft and detecting the target situation.

Second, since the present invention is provided with the receiving module 2, the three-way radio frequency echo signal generated by the echo simulation module 1 is down-converted to the intermediate frequency band, and then transmitted to the signal processing module 3 for processing. This hardware circuit realizes radar The processing flow of the receiver can simulate the receiver system of the radar to assist in the completion of the antenna and transmitter test work in the production stage and reduce the test cost;

Third, the present invention performs signal processing on the received three-way intermediate frequency signals through the signal processing module 3 provided, which not only can complete the algorithm verification and hardware design evaluation work of the radar signal processing platform, but also can assist in the completion of the receiver in the production stage. Test works.

Description of drawings

Fig. 1 is a schematic diagram of the present invention;

Fig. 2 is the schematic diagram of the echo simulation module in the present invention;

Fig. 3 is a schematic diagram of the receiving module in the present invention;

Fig. 4 is a schematic diagram of a signal processing module in the present invention;

Fig. 5 is the simulation flowchart of the present invention;

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings.

Referring to FIG. 1 , the present invention includes a monopulse radar echo simulation module 1 , a receiving module 2 and a signal processing module 3 . Wherein, the receiving module 2 is unidirectionally connected with the echo simulation module 1 and the signal processing module 3 respectively. Among them, the echo simulation module 1 is used to generate the three-channel radio frequency echo signal of the sum channel, the azimuth difference and the pitch difference with a carrier frequency of 16.5 GHz, and transmit it to the receiving module 2; The three-channel signals of the difference channel are subjected to secondary down-conversion processing to down-convert the radio frequency echo to the intermediate frequency band; then send it to the signal processing module 3 for ADC sampling and signal processing to obtain the distance, speed, pitch angle, and azimuth angle of the target and AGC control information.

Referring to FIG. 2 , the echo simulation module 1 includes a baseband echo sub-module 11 and an echo simulation sub-module 12 . Wherein, the baseband echo submodule 11 includes a parameter setting unit 111, a transmitting unit 112, an antenna unit 113, a target RCS unit 114, a clutter signal unit 115, and a baseband echo generating unit 116; the echo simulation submodule 12 includes a signal storage unit 121 , an analog signal generation unit 122 , and an up-conversion unit 123 .

The parameter setting unit 111 is used to set the basic parameters of the carrier aircraft, including carrier aircraft flight height, three-axis velocity and attitude information, and transmit the parameter information to the baseband echo generation unit 116;

The transmitting unit 112 is used to configure the frequency, power, pulse width, pulse period and modulation mode of the transmitting signal, and transmit the parameter information to the baseband echo generating unit 116;

The antenna unit 113 is used to generate the antenna pattern of the sum channel, the azimuth difference channel and the elevation difference channel, and transmit the parameter information to the baseband echo generation unit 116;

The target RCS unit 114 is used to set the target quantity and RCS characteristics, and transmit the parameter information to the baseband echo generating unit 116;

The clutter signal unit 115 is used to set the clutter signal model and the clutter power, and transmit the parameter information to the baseband echo generation unit 116;

The baseband echo generating unit 116 is configured to generate baseband echo data of the sum channel, the azimuth difference channel and the elevation difference channel.

The signal storage unit 121 is used for storing the generated baseband echo signal data;

The analog signal generation unit 122 is used to convert the stored baseband echo data into an analog signal and output it to the frequency up conversion unit 123;

The up-conversion unit 123 is used for up-converting the generated analog signal to a radio frequency band.

In this example, the units and modules of the echo simulation module 1 are set but not limited to the following parameters:

In the parameter setting unit 111, the flight altitude of the carrier aircraft is set to 500m, the X-axis speed is 20km/h, the Y-axis speed and the Z-axis speed are 0km/h, the pitch attitude angle of the carrier aircraft is set to 0°, and the roll attitude angle is set to 0°;

The transmitting signal frequency in the transmitting unit 112 is set to 16.5GHz, the transmitting power is 150W, the pulse width is 10us, and the pulse period is 100us;

Antenna unit 113 sets four antenna beams, the gain is 25dB, the beam width is 5°, and the deviation angle between each beam is 2°. The sum antenna pattern, the azimuth difference antenna pattern and the antenna pattern of the radar are generated using these four antenna beams. Pitch difference antenna pattern;

The target in the target RCS unit 114 is set as a car, the quantity is 1, and the RCS is 100m ² ;

The clutter signal model in the clutter signal unit 115 is set to Rayleigh type;

The baseband echo generation unit 116 generates the baseband echo data of the sum channel, the azimuth difference channel and the elevation difference channel according to the above-mentioned setting parameters.

The signal storage unit 121 is implemented by a large-capacity DDR chip, and the analog signal generation unit 122 uses FPGA and DAC chips to read the baseband echo signal data in the signal storage unit, and convert it into an analog signal and output it to the up-conversion unit 123. The unit 123 up-converts the analog signal to 16.5 GHz and outputs it through three SMA radio frequency interfaces.

With reference to Fig. 3, described receiving module 2 comprises and channel 21, elevation difference channel 22, azimuth difference channel 23, control submodule 24, frequency source 25 and power supply submodule 26; Wherein control submodule 24 comprises communication unit 241 and control unit 242;

The sum channel 21, the pitch difference channel 22 and the azimuth difference channel 23 are used to down-convert the radio frequency echo signal to the intermediate frequency band: after the radio frequency echo signal enters these three channels, it first passes through the low noise amplifier LNA and filters Converter: first down-convert the frequency through the mixer and the high local oscillator signal; then amplify through the amplifier, and then perform the second down-conversion through the mixer and the low local oscillator signal; after passing through the filter and the numerically controlled attenuator, then After being amplified by the amplifier and filtered by the filter, the intermediate frequency signals of the three channels are output;

The frequency source 25 is used to generate the high local oscillator and low local oscillator signals required for down-conversion of the three channels and the synchronization signal of the echo simulation module 1 and the clock signal of the signal processing module 3;

The communication unit 241 is used to receive control information from the signal processing module 3, and transmit the received information to the control unit 242;

The control unit 242 is used to transmit control signals to the digitally controlled attenuators of the three channels.

In this example, the receiving module 2 is provided with 8 signal interfaces and 1 control interface; 3 RF signal SMA input ports are used to receive the three-channel RF echo signals generated by the echo simulation module; this module has 5 signal interfaces Output interface, including 3 intermediate frequency signal SMA output interfaces, 1 clock signal SMA output interface, and 1 synchronization signal SMA output interface; the control interface is a 15-core micro-rectangular socket, which is connected to the signal processing module 3;

The sum channel 21, the pitch difference channel 22 and the azimuth difference channel 23 first pass the radio frequency signal through the low noise amplifier LNA and the filter, and then mix it with the 1.6GHz high local oscillator signal through the mixer for the first down-conversion process, and convert the 16.5GHz± The fd signal is down-converted to 1.6GHz±fd signal; then through the amplifier, and then mixed with the 150MHz low local oscillator signal for the second down-conversion process, the 1.6GHz±fd signal is frequency-converted to 150MHz±fd; then passed The filter and the numerically controlled attenuator are output to the signal processing module 3 after passing through the amplifier and the filter;

The communication unit 241 of the control sub-module 24 uses the RS422 interface chip to communicate, receives the AGC control signal transmitted by the signal processing module 3, and transmits it to the control unit 242; the control unit 242 uses the FPGA chip to solve the control signal and sends it to three A digitally controlled attenuator in the channel; the control sub-module 24 is connected to the signal processing module 3 through a control interface, and the communication mode is an RS422 serial port;

The frequency source 25 provides stable high local oscillator and low local oscillator signals to the three channels, and outputs synchronous signals and clock signals at the same time; the high local oscillator signal frequency is 1.6GHz, the low local oscillator signal frequency is 150MHz, and the synchronous signal generated is 10MHz, which is output to the back The wave simulation module 1 generates a clock signal with a frequency of 120MHz, which is output to the signal processing module 3;

The power supply sub-module 26 converts the 220V AC voltage into ±12V DC power suitable for the module.

Referring to FIG. 4 , the signal processing module 3 includes an ADC submodule 31 , a signal processing submodule 32 , a storage submodule 33 and a power supply submodule 34 . Wherein, the ADC submodule 31 includes a sum channel unit 311, a pitch difference channel unit 312 and an azimuth difference channel unit 313; the signal processing submodule 32 includes a signal processing unit 321, a data processing unit 322 and a communication unit 323;

The sum channel unit 311 is used to perform ADC sampling on the sum channel intermediate frequency signal, and transmit the sampled signal to the signal processing submodule 32;

The pitch difference channel unit 312 is used to perform ADC sampling on the pitch difference channel intermediate frequency signal, and transmit the sampled signal to the signal processing submodule 32;

The azimuth channel unit 313 is used to perform ADC sampling on the intermediate frequency signal of the azimuth channel, and transmit the sampled signal to the signal processing sub-module 32 .

The signal processing unit 321 is used to implement radar signal processing related algorithms, and transmit the processed data to the data processing unit 322;

The data processing unit 322 is used to implement algorithms related to radar data processing;

The communication unit 323 is used for communicating with the receiving module 2 and outputting the simulation results of the system.

The storage sub-module 33 is used for storing the data of the signal processing sub-module 32 and loading the chip program.

In this example, the signal processing module 3 is provided with 4 SMA interfaces, 3 intermediate frequency SMA input interfaces, and 1 clock signal SMA input interface;

The ADC submodule 31 carries out AD sampling to the intermediate frequency signals of the three channels in the sum channel unit 311, the pitch difference channel unit 312 and the azimuth difference channel unit 313 respectively through 3 SMA input interfaces, and the sampling frequency is 500MHz, and then the sampling signal is transmitted to Signal processing sub-module;

The signal processing unit 321 of the signal processing sub-module 32 adopts but is not limited to the XCVX690T model FPGA chip of XILINX, in which the received sampling signal is filtered and pulse compressed, and the processed signal is transmitted to the data processing unit 322; The data processing unit 322 yuan adopts but is not limited to TI's TMS320C6678 multi-core DSP chip. In this unit, the moving target indication MTI, moving target detection MTD, constant false alarm rate detection CFAR, defuzzification, and amplitude angle measurement of monopulse radar are realized. and AGC control detection processing, obtain the corresponding processed target distance, speed, pitch angle, azimuth and AGC control information, and transmit to the communication unit 323; the communication unit 323 transmits the AGC control information to the receiving module 2, and outputs the target Distance, speed, pitch angle and azimuth angle information; the communication unit 323 uses the RS422 interface chip for communication;

The storage sub-module 33 uses, but is not limited to, FLASH memory chips to store data and load programs; the power supply sub-module 34 converts 220V AC voltage into ±24V DC power suitable for the module.

Referring to Fig. 5, the method for simulating the airborne monopulse radar by using the above-mentioned system is realized as follows:

S1, initial parameters are set in the baseband echo sub-module 11 of the radar echo simulation module 1, and the three-way baseband echo data of the sum channel, the pitch difference channel and the azimuth difference channel of the monopulse radar during the flight of the carrier aircraft are simulated;

S2, transmit the echo data of the three-way baseband to the echo simulation sub-module 12 to generate a radio frequency echo signal, and output it to the receiving module 2;

S3, the receiving module 2 performs down-conversion processing on the three-way radio frequency echo signals to obtain three-way intermediate frequency signals, and transmits them to the signal processing module 3;

S4, the signal processing module 3 sequentially performs sampling and signal processing on the three-way intermediate frequency signals through its ADC submodule 31 and signal processing submodule 32:

S41) The ADC submodule 31 samples the three-way intermediate frequency signal, and transmits the sampled signal to the signal processing unit 321 in the signal processing submodule 32;

S42) The signal processing unit 321 performs filtering and pulse compression processing on the three-way sampling signals, and transmits the processed three-way signals to the data processing unit 322;

S43) The data processing unit 322 simultaneously performs the following two processes on the three-way sampling signals:

The first method: firstly perform moving target indication MTI and moving target detection MTD processing on the three-way sampling signal, and then perform constant false alarm rate detection CFAR and defuzzification processing on the processed sum channel signal at the same time, and respectively integrate the pitch difference channel and The azimuth difference channel signal is processed by single-pulse ratio-amplitude angle measurement, and the corresponding processed target distance, speed, pitch angle and azimuth angle are obtained, and transmitted to the communication unit 323;

The second method: performing automatic gain control (AGC) detection on the amplitude of the three-way sampling signal, obtaining AGC control information, and transmitting it to the communication unit 323;

S5, the communication unit 323 transmits the AGC control information to the receiving module 2, and outputs the distance, speed, pitch angle and azimuth angle information of the target, so as to realize the whole process simulation of the airborne monopulse radar from the antenna front end to the rear end signal processing.

The above description is only a specific example of the present invention, and does not constitute any limitation to the present invention. Obviously, for those skilled in the art, after understanding the content and principles of the present invention, it is possible without departing from the principles and structures of the present invention. In some cases, various modifications and changes in form and details are made, but these modifications and changes based on the idea of the present invention are still within the protection scope of the claims of the present invention.

Claims (8)

1. The semi-physical simulation system of the airborne monopulse radar is characterized by comprising an echo simulation module (1), a receiving module (2) and a signal processing module (3), wherein the receiving module (2) is respectively connected with the monopulse radar echo simulation module (1) and the signal processing module (3) in a one-way manner;

the echo simulation module (1) comprises a baseband echo submodule (11) and an echo simulation submodule (12), wherein the baseband echo submodule is used for generating a baseband echo signal with target characteristics and carrier flight attitude, and the echo simulation submodule is used for up-converting the baseband echo signal and transmitting the up-converted radio frequency signal to the receiving module (2);

the receiving module (2) is used for transmitting the intermediate frequency signal after the down-conversion of the radio frequency signal to the signal processing module (3); the device comprises a sum channel (21), a pitch difference channel (22), a azimuth difference channel (23), a control submodule (24), a frequency source (25) and a power submodule (26); the three channels are provided with numerical control attenuators, and attenuation of the attenuators is controlled by a control submodule; the frequency source generates high local oscillation signals, low local oscillation signals, synchronous signals of the echo simulation module and clock signals of the signal processing module, which are needed by down-conversion of three channels;

the signal processing module (3) comprises an ADC sub-module (31), a signal processing sub-module (32), a storage sub-module (33) and a power supply sub-module (34), wherein the ADC sub-module samples the intermediate frequency signal and transmits the sampled signal to the signal processing sub-module; the signal processing sub-module performs signal processing on the sampling signal; the storage sub-module is used for storing data of the signal processing sub-module and loading a chip program.

2. The system according to claim 1, characterized in that the baseband echo submodule (11) comprises a parameter setting unit (111), a transmitting unit (112), an antenna unit (113), a target RCS unit (114), a clutter signal unit (115) and a baseband echo generating unit (116);

the parameter setting unit (111) is used for setting basic parameters of the carrier, including information such as flight height, triaxial speed and attitude information of the carrier, and transmitting the basic parameters to the baseband echo generating unit;

the transmitting unit (112) is used for configuring the frequency, the power, the pulse width, the pulse period and the modulation mode of a transmitting signal and transmitting the transmitting signal to the baseband echo generating unit;

the antenna unit (113) is used for generating an antenna pattern of a sum channel, a azimuth difference channel and a pitch difference channel and transmitting the antenna pattern to the baseband echo generating unit;

the target RCS unit (114) is used for setting the target quantity and RCS characteristics and transmitting the target quantity and RCS characteristics to the baseband echo generation unit;

the clutter signal unit (115) is used for setting a clutter signal model and clutter power and transmitting the clutter signal model and the clutter power to the baseband echo generating unit;

the baseband echo generation unit (116) is used for generating baseband echo data of the sum channel, the azimuth difference channel and the elevation difference channel.

3. The system according to claim 1, characterized in that the echo simulation sub-module (12) comprises a signal storage unit (121), an analog signal generation unit (122) and an up-conversion unit (123);

the signal storage unit (121) is used for storing the generated baseband echo data;

the analog signal generating unit (122) is used for converting the stored baseband echo data into an analog signal and outputting the analog signal to the up-conversion unit;

the up-conversion unit (123) is used for up-converting the generated analog signal to a radio frequency band.

4. The system according to claim 1, characterized in that the control submodule (24) comprises a communication unit (241) and a control unit (242);

the communication unit (241) is used for receiving the control information from the signal processing module and transmitting the received information to the control unit;

the control unit (242) is used for transmitting control signals to the numerical control attenuators of the three channels.

5. The system according to claim 1, characterized in that the ADC sub-module (31) comprises a sum channel unit (311), a pitch difference channel unit (312), a azimuth difference channel unit (313);

the sum channel unit (311) is used for carrying out ADC (analog-to-digital conversion) sampling on the sum channel intermediate frequency signal and transmitting the sampled signal to the signal processing sub-module;

the pitching difference channel unit (312) is used for carrying out ADC (analog-to-digital conversion) sampling on the pitching difference channel intermediate frequency signal and transmitting the sampled signal to the signal processing sub-module;

the azimuth difference channel unit (313) is used for carrying out ADC sampling on the azimuth difference channel intermediate frequency signal and transmitting the sampled signal to the signal processing sub-module.

6. The system according to claim 1, characterized in that the signal processing sub-module (32) comprises a signal processing unit (321), a data processing unit (322) and a communication unit (323);

the signal processing unit (321) is used for realizing a radar signal processing related algorithm and transmitting the processed data to the data processing unit;

the data processing unit (322) is used for realizing a radar data processing related algorithm;

the communication unit (323) is used for communicating with the receiving module and outputting the simulation result of the system.

7. A method of simulating an airborne monopulse radar using the system of claim 1, implemented as follows:

setting initial parameters in a baseband echo submodule (11) of a radar echo simulation module (1), and simulating three baseband echo data, namely a sum channel, a pitching difference channel and a azimuth difference channel of a monopulse radar when a carrier flies;

transmitting the three paths of baseband echo data to an echo simulation sub-module (12) to generate a radio frequency echo signal and outputting the radio frequency echo signal to a receiving module (2);

the receiving module (2) performs down-conversion processing on the three paths of radio frequency echo signals to obtain three paths of intermediate frequency signals, and transmits the three paths of intermediate frequency signals to the signal processing module (3);

the signal processing module (3) sequentially samples and processes the three paths of intermediate frequency signals through the ADC submodule (31) and the signal processing submodule (32) and outputs the detection target distance, speed, pitch angle and azimuth angle of the carrier, so that the full-flow simulation of the signal processing of the airborne monopulse radar from the front end to the rear end of the antenna is realized.

8. The method according to claim 7, wherein the ADC sub-module (31) and the signal processing sub-module (32) sample and process the three intermediate frequency signals sequentially, as follows:

the ADC submodule (31) samples three paths of intermediate frequency signals and transmits the sampled signals to a signal processing unit (321) in the signal processing submodule (32);

the signal processing unit (321) performs filtering and pulse compression processing on the three paths of sampling signals and transmits the processed three paths of signals to the data processing unit (322);

the data processing unit (322) performs the following two processes on the three paths of sampling signals simultaneously:

first kind: firstly, performing mobile target indication MTI and mobile target detection MTD processing on three paths of sampling signals, then performing constant false alarm rate detection CFAR and defuzzification processing on processed sum channel signals, performing single pulse amplitude comparison angle measurement processing on the processed sum channel signals and pitch difference channel signals respectively to obtain corresponding processed target distances, speeds, pitch angles and azimuth angles, and transmitting the processed sum channel signals to a communication unit (323);

second kind: performing Automatic Gain Control (AGC) detection on the amplitudes of the three paths of sampling signals to obtain AGC control information, and transmitting the AGC control information to a communication unit (323);

the communication unit (323) transmits AGC control information to the receiving module (2) and outputs distance, speed, pitch angle, and azimuth angle information of the detection target.