CN103630894A - Broadband multichannel coherent radar imaging system and control method thereof - Google Patents

Abstract

The invention provides a broadband multi-channel coherent radar imaging BMCIRS system and a control method thereof. The control method changes the control of each hardware module in the BMCIRS system from manual to automatic, and the hardware modules of the system are organically integrated, which has the advantages of automatic data collection and coordinated work, thus greatly improving the control efficiency.

Description

Broadband multi-channel coherent radar imaging system and its control method

technical field

The invention relates to the field of radar technology, in particular to a control method of a broadband multi-channel coherent radar imaging system BMCIRS.

Background technique

In the development process of microwave imaging technology today, broadband and multi-channel are one of the important development directions of radar imaging system. In order to build a stable, functional imaging system product that meets application requirements, it is necessary to build a corresponding experimental verification platform in advance. Broadband Multi-channel Coherent Imaging Radar System (BMCIRS: Broadband Multi-channel Coherent Imaging Radar System) is an experimental verification platform composed of general instruments and customized equipment.

However, the existing BMCIRS system is composed of general-purpose equipment and customized equipment, and the operation and control of the system can only be performed manually at the panel of the equipment, but such an operation method does not have automation, adaptability, and coordination And integration characteristics, on the one hand, the control efficiency is low and time-consuming, on the other hand, the lack of feedback verification is prone to control errors.

Contents of the invention

(1) Technical problems to be solved

In view of the above technical problems, the present invention provides a BMCIRS system and its control method.

(2) Technical solution

According to one aspect of the present invention, a broadband multi-channel coherent radar imaging BMCIRS system is provided. The system includes: baseband signal generation module, including at least one arbitrary waveform generator, each arbitrary waveform generator occupies a transmission channel; quadrature modulation up-conversion module, including at least one vector microwave signal source, each vector microwave signal The source occupies a transmission channel, and is used in conjunction with an arbitrary waveform generator that constitutes a baseband signal generation module at this channel; the channel switching module at the transmission end includes a multi-channel microwave switch device, and the input common terminal of the multi-channel microwave switch device Connect the modulated RF pulse signal output by the quadrature modulation up-conversion module, multiple output terminals are respectively connected and output the RF signal to different transmitter power amplifier modules; the channel switching module at the receiving end includes a multi-channel microwave switch device, the The multiple input terminals of the multi-channel microwave switchgear are connected to different receiving antennas, and the output common end is connected to the receiver down-conversion module; the receiver down-conversion module includes at least one multi-channel down-converter, and its first input terminal is connected to the frequency converter. The output terminal of the source module, its second input terminal is connected to the output common terminal of the channel switching module of the receiving end, and its output terminal is connected to the AD sampling and storage module; the AD sampling and storage module is used for triggering by an external timer, The external sampling clock signal output by the frequency source module is used as the sampling clock to perform high-speed data acquisition and recording of the intermediate frequency signal output by the down-conversion module of the receiver to form the required original echo data; the frequency source module includes at least two analog signal Generators, wherein one analog signal generator provides local oscillator signal input for the receiver down-conversion module, and the other analog signal generator provides external sampling clock signals for the baseband signal generation module and AD sampling and storage module; the timer module , used to provide trigger input pulses for the baseband signal generation module and the AD sampling and storage module, and provide switch gating signals for the transmitter channel switch module and the receiver channel switch module; AC modulation up-conversion module, transmitter channel switch module, receiver channel switch module, receiver down-conversion hardware module, AD sampling and storage hardware module, frequency source module, and timer module are connected to configure the above hardware devices Finally, the broadband multi-channel coherent radar imaging simulation is carried out through coordinated operation.

According to another aspect of the present invention, there is also provided a control method for the BMCIRS system, which is used to control the above-mentioned BMCIRS system, and is executed by the control device, including: Step A: receiving the system operation mode information input by the user, that is, the system operation transmission The number of channels N and the number of receiving channels M; Step B: Configure and initialize the corresponding hardware devices according to the system working mode information; Step C: Receive the system working parameter set input by the user, and work on the system through the constraint equations The parameters in the parameter set are analyzed for parameter feasibility, fed back to the user for modification, until the system working parameter set meets the requirements; Step D: Receive the "transmission signal parameter" set input by the user, perform pre-distortion correction of the transmitted signal, and derive the pre-distortion of the transmitted signal digital waveform file, and send the transmitted signal predistortion digital waveform file as a parameter file to the baseband signal generation module; step E: send each control parameter of the system working parameter set to the corresponding hardware module; transmit the transmitted signal predistortion digital The waveform file is sent to the baseband signal generation module; step F, instructing each device to perform parameter configuration according to the input control parameters, and receiving hardware device feedback operating parameters, and performing system verification to eliminate errors and conflicts in parameter setting; and step G, The control device sends a startup command to each hardware device to start the broadband multi-channel coherent radar imaging simulation.

(3) Beneficial effects

As can be seen from the foregoing technical solutions, the BMCIRS system of the present invention and its control method have the following beneficial effects:

(1) The control of each hardware module in the BMCIRS system is changed from manual to automatic, and the hardware modules of the system are organically integrated together, which has the advantages of automatic data collection and coordinated work, thus greatly improving the control efficiency;

(2) BMCIRS system control under various working modes can be realized, and different software and hardware configuration schemes can be adaptively loaded under different working modes, which greatly improves the flexibility of system control;

(3) It has the function of feedback verification for the parameter design and parameter setting of the BMCIRS system, which is convenient for detecting and correcting conflicts and abnormalities in the process of parameter design and parameter setting, and greatly improves the robustness of the system control.

Description of drawings

Fig. 1 is the principle schematic diagram of the BMCIRS system of the embodiment of the present invention;

Fig. 2 is the structural representation of the BMCIRS system of the embodiment of the present invention;

Fig. 3 is the control flowchart of BMCIRS system control method of the present invention;

FIG. 4-1 is a schematic diagram of the structure of the BMCIRS system in the "single send, single receive" mode in the BMCIRS system control method of the embodiment of the present invention;

FIG. 4-2 is a schematic diagram of the structure of the BMCIRS system in the "single-send-multiple-receive" mode in the BMCIRS system control method of the embodiment of the present invention;

Fig. 4-3 is the schematic diagram of the structure of the BMCIRS system in the "multiple transmission and single reception" mode in the BMCIRS system control method of the embodiment of the present invention;

4-4 are schematic structural diagrams of the BMCIRS system in the "multi-send and multi-receive" mode in the BMCIRS system control method of the embodiment of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be described in further detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

It should be noted that, in the drawings or descriptions of the specification, similar or identical parts all use the same figure numbers. Implementations not shown or described in the accompanying drawings are forms known to those of ordinary skill in the art. Additionally, while illustrations of parameters including particular values may be provided herein, it should be understood that the parameters need not be exactly equal to the corresponding values, but rather may approximate the corresponding values within acceptable error margins or design constraints.

The invention provides a BMCIRS system and a control method thereof. The system and method use the programming control of the system hardware module equipment to realize communication and synchronization among various equipment, and control the generation, emission, reception, sampling and storage of signals, so as to realize the experimental verification of new theory and new technology of microwave imaging .

FIG. 1 is a schematic diagram of the principle of the BMCIRS system according to an embodiment of the present invention. Please refer to Figure 1. The BMCIRS system uses ground vehicles as the installation platform, realizes antenna aperture synthesis and azimuth resolution through the movement of the platform, and realizes real aperture resolution in the array direction by using array antennas.

FIG. 2 is a schematic structural diagram of a BMCIRS system according to an embodiment of the present invention. Please refer to Fig. 2, the BMCIRS system of the embodiment of the present invention includes the following hardware modules:

1. The baseband signal generation module includes at least one arbitrary waveform generator, each arbitrary waveform generator occupies a transmission channel, and is used in conjunction with a vector microwave signal source that constitutes a quadrature modulation up-conversion module at this channel. The arbitrary waveform generator is used to use the external sampling clock signal output by the frequency source module as the sampling clock according to the digital waveform sequence input by the user under the trigger of the external timer, and convert it into an analog baseband transmitting signal waveform and corresponding pulse through DA synthesis The envelope signal is input as a vector microwave signal source used in conjunction with it to form a quadrature modulation up-conversion module;

2. The quadrature modulation up-conversion module includes at least one vector microwave signal source, each vector microwave signal source occupies one transmission channel, and is used in conjunction with an arbitrary waveform generator forming a baseband signal generation module at this channel. The vector microwave signal source is used to perform quadrature modulation and pulse modulation on the analog baseband transmit signal waveform and the corresponding pulse envelope signal output by its matching arbitrary waveform generator to generate modulated radio frequency pulse signals and their pulse envelopes as The input signal of the channel switching module at the transmitter;

3. The channel switching module at the transmitting end, including a multi-channel microwave switching device. The input common end of the multi-channel microwave switchgear is connected to the modulated radio frequency pulse signal output by the quadrature modulation up-conversion module, and the multiple output ends are respectively connected and output the radio frequency signals to different transmitter power amplifier modules. When working, according to the control instruction sent by the receiving control device, the switch strobe signal output by the timer module is used as the trigger signal to switch the radio frequency signal in different paths in the microwave switch device, and the radio frequency signal is turned on to different transmitter power amplifiers The power is amplified and radiated through the transmitting antenna, so as to realize the time expansion of the transmission channel of the BMCIRS system.

4. The channel switching module at the receiving end, including a multi-channel microwave switching device. Multiple input terminals of the multi-channel microwave switch device are connected to different receiving antennas, and a common output terminal is connected to a receiver down-conversion module. When working, according to the received control command sent by the control device, the switch strobe signal output by the timer module is used as the trigger signal to switch the path of the signal received at different antennas in the microwave switch device, and the radio frequency signal is time-shared. To the receiver down-conversion module, so as to realize the time expansion of the receiving channel of the BMCIRS system.

5. The receiver down-conversion module includes at least one multi-channel down-converter. The multi-channel down-converter uses the frequency source module to output the local oscillator signal as a mixing signal, and receives the output from the channel switching module at the receiving end and the receiving antenna. RF pre-selection, low-noise amplification, down-conversion mixing, intermediate frequency filtering, and amplification of the RF signal, and the output is an intermediate frequency signal, which is used as the input of the AD sampling and storage hardware module;

6. The AD sampling and storage module is used to perform the intermediate frequency signal output by the down-conversion module of the receiver with the external sampling clock signal output by the frequency source module as the sampling clock under the trigger of the external timer according to the parameter setting of the control device. High-speed data acquisition and recording, and finally form the required original echo data;

7. A frequency source module, including at least two analog signal generators. According to the parameter settings of the control equipment, one analog signal generator provides local oscillator signal input for the receiver down-conversion module, and the other analog signal generator provides external sampling clock signals for the baseband signal generation module and AD sampling and storage module;

8. The timer module is used to set the parameters of the control device. On the one hand, it provides trigger input pulses for the baseband signal generation module and AD sampling and storage module, and on the other hand, it provides switches for the channel switching module at the transmitting end and the channel switching module at the receiving end. strobe signal;

9. Control equipment, together with the above-mentioned baseband signal generation module, quadrature modulation up-conversion module, transmitter channel switch module, receiver channel switch module, receiver down-conversion hardware module, AD sampling and storage hardware module, frequency source module, timing Connected with the controller module, it is used to perform broadband multi-channel coherent radar imaging simulation through coordinated operation after configuring the above hardware devices.

The control device performs IO communication connection with the above-mentioned other hardware modules through the interface bus LXI (LAN), wherein in the above-mentioned hardware modules, the baseband signal generation module, the quadrature modulation up-conversion module, the channel switching module of the transmitting end, the channel switching module of the receiving end, The frequency source module and the timer module are all composed of general instruments and equipment, which conform to the VISA (Virtual Instrument Software Architecture) standard protocol of the National Instruments NI (National Instrument) company, and the control equipment controls it through the VISA application program interface. ; The receiver down-conversion hardware module, AD sampling and storage hardware module in the hardware module are composed of customized equipment, and its application program interface is also customized according to the VISA standard protocol to be controlled by the control equipment. Therefore, the control devices are controlled by the VISA standard protocol.

On the basis of the BMCIRS system in the above embodiment, the present invention also provides a control method for the above BMCIRS system. Referring to Fig. 3, the control method is executed by the above-mentioned control device, including:

Step A: Receive the system working mode information input by the user, that is, the number N of transmission channels and the number M of receiving channels of the system working, wherein the system working mode information includes at least one of the following schemes: single transmission and single reception, N= 1, M=1 working mode, single sending and multiple receiving, N=1, M≥2 working mode, multiple sending and single receiving, N≥2, M=1 working mode, multiple sending and multiple receiving, N≥2, M≥2 working mode ;

Step B: Configure and initialize the corresponding hardware devices according to the working mode information of the system. If the single-sending and single-receiving working mode is selected, perform step B1; if the single-sending and multiple-receiving working mode is selected, perform step B2; In the single-receipt working mode, perform step B3; if you choose the multi-transmission and multi-receive working mode, perform step B4;

Sub-step B1, configuring the device according to the single-send-single-receive working mode, this sub-step further includes:

Sub-step B1a, configure a waveform generator to form a baseband signal generation module, and send instructions to it to initialize it;

In sub-step B1b, configure a vector microwave signal source matched with the above-mentioned waveform generator to form a quadrature modulation up-conversion module, and send instructions to it to initialize it;

Sub-step B1c, configuring a multi-channel down-converter with K channels to form a receiver down-conversion module, and sending an instruction to it to activate any one of its K channels as a receiving channel;

Sub-step B1d, configure a multi-channel high-speed data acquisition and recorder with L channels to form an AD sampling and storage module, and send an instruction to it to activate any one of its L channels as a sampling channel;

Sub-step B1e, configure two analog signal generators as the external sampling clock frequency source and down-converted local oscillator frequency source to form the frequency source module, and send instructions to it to initialize it;

Sub-step B1f, configure a pulse signal generator to form a timer module, and send instructions to it to initialize it; perform step C;

After executing the above B1a to B1f, the hardware structure of the BMCIRS system is shown in Figure 4-1.

Sub-step B2, configuring the device according to the single-send-multiple-receive working mode, this sub-step further includes:

Sub-step B2a, configure an arbitrary waveform generator to form a baseband signal generation module, and send instructions to it to initialize it;

In sub-step B2b, configure a vector microwave signal source to form a quadrature modulation up-conversion module, and send instructions to it to initialize it;

Sub-step B2c, configure a multi-channel down-converter with K channels to form a receiver down-conversion module, and send instructions to it. When M≤K, make its M channels activated as receiving channels. When In the case of M>K, all K channels are activated as receiving channels;

Sub-step B2d, configure a multi-channel high-speed data acquisition and recorder with L channels to form an AD sampling and storage module, and send instructions to it, and when M≤L, make its M channels activated as sampling channels, when M>L, all L channels are activated as sampling channels;

Sub-step B2e, configure a microwave switch network device to form a channel switching module at the receiving end, and send instructions to it to initialize it;

Sub-step B2f, configure two analog signal generators as the external sampling clock frequency source and down-converted local oscillator frequency source to form a frequency source module, and send instructions to it to initialize it;

Sub-step B2g, configure a pulse signal generator to form a timer module, and send instructions to it to initialize it; perform step C;

After executing the above B2a to B2g, the hardware structure of the BMCIRS system is shown in Figure 4-2.

Sub-step B3, configuring the device according to the multi-send-single-receive working mode, this sub-step further includes:

Sub-step B3a, configure two arbitrary waveform generators to form the two channels of the baseband signal generation module, and send instructions to them to initialize them;

In sub-step B3b, configure two vector microwave signal sources to form two channels of the quadrature modulation up-conversion module, and send instructions to them to initialize them; when the system operation mode information N=2 input by the user, execute step B3d;

Sub-step B3c, configuring a microwave switch network device to form a channel switching module at the transmitter, and sending instructions to it to initialize it;

Sub-step B3d, configuring a multi-channel down-converter with the number of channels K to form a receiver down-conversion module, and sending an instruction to it to activate any one of its K channels as a receiving channel;

Sub-step B3e, configure a multi-channel high-speed data acquisition and recorder with L channels to form an AD sampling and storage module, and send an instruction to it to activate any one of its L channels as a sampling channel;

Sub-step B3f, configure two analog signal generators as external sampling clock frequency source and down-converted local oscillator frequency source to form a frequency source module, and send instructions to it to initialize it;

Sub-step B3g, configure a pulse signal generator to form a timer module, and send instructions to it to initialize it; perform step C;

After executing the above B3a to B3g, the hardware structure of the BMCIRS system is shown in Figure 4-3.

Sub-step B4, configuring the device according to the multi-sending and multi-receiving working mode, this sub-step further includes:

Sub-step B4a, configure two arbitrary waveform generators to form two channels of the baseband signal generation module, and send instructions to them to initialize them;

In sub-step B4b, configure two vector microwave signal sources to form two channels of the quadrature modulation up-conversion module, and send instructions to them to initialize them; when the system operation mode information N=2 input by the user, execute step B4d;

Sub-step B4c, configuring a microwave switch network device to form a channel switching module at the transmitter, and sending instructions to it to initialize it;

Sub-step B4d, configure a multi-channel down-converter with the number of channels K to form a receiver down-conversion module, and send instructions to it, when M≤K, make its M channels activated as receiving channels, when In the case of M>K, all K channels are activated as receiving channels;

Sub-step B4e, configure a multi-channel high-speed data acquisition and recorder with L channels to form an AD sampling and storage module, and send instructions to it, and when M≤L, make its M channels activated as sampling channels, when M>L, all L channels are activated as sampling channels;

Sub-step B4f, configure a microwave switch network device to form a channel switching module at the receiving end, and send instructions to it to initialize it;

Sub-step B4g, configure two analog signal generators as external sampling clock frequency source and down-conversion local oscillator frequency source to form a frequency source module, and send instructions to it to initialize it;

Sub-step B4h, configure a pulse signal generator to form a timer module, and send instructions to it to initialize it; perform step C;

After executing the above B4a to B4g, the hardware structure of the BMCIRS system is shown in Figure 4-4.

Step C: Receive the system working parameter set input by the user, conduct parameter feasibility analysis on the parameters in the system working parameter set through the constraint equation group, and feed back to the user for modification until the system working parameter set meets the requirements;

The parameters in the system working parameter set are used to generate the input control parameters of each hardware module device, including system working frequency f _c , bandwidth B, pulse width τ, sampling frequency f _s , pulse repetition frequency PRF, peak transmit power P _t , antenna gain G. Azimuth beam width θ _a , elevation beam width θ _c , platform velocity V, platform height H, incident angle range Ф∈[Ф ₁ , Ф ₂ ], receiver noise factor F _n , system loss L _n , receiver down Variable frequency local oscillator frequency f ₀ , intermediate frequency output frequency f _I , the number of transmitting channels N and the number of receiving channels M and other parameters; the constraint equations include:

$\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; ></span>\mathrm{<span\; class="notranslate">\; B</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; PRF</span>}<span\; class="notranslate">\; ></span>\frac{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; V</span>}}{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; PRF</span>}<span\; class="notranslate">\; <</span>\frac{\mathrm{<span\; class="notranslate">\; C</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; swath</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; \&Phi;</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>\\ {\mathrm{<span\; class="notranslate">\; NE\&sigma;</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; =</span>\frac{{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 3</span>}}{\mathrm{<span\; class="notranslate">\; KT</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; R</span>}}^{\mathrm{<span\; class="notranslate">\; 3</span>}}{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; V</span>}}{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; av</span>}}{\mathrm{<span\; class="notranslate">\; G</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}^{\mathrm{<span\; class="notranslate">\; 3</span>}}{\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}}}\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; \&Phi;</span>}<span\; class="notranslate">\; \&le;</span>\mathrm{<span\; class="notranslate">\; Threshold</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>\\ {\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; <</span>{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; swath</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; [</span>\mathrm{<span\; class="notranslate">\; the\; tan</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&Phi;</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; the\; tan</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&Phi;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span><span\; class="notranslate">\; <</span>{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>\end{array}\right.$

Among them, formula (1) is the Nyquist sampling constraint equation;

Equation (2) is the azimuth fuzzy constraint equation, and D is the azimuth dimension of the antenna;

Equation (3) is the distance fuzzy constraint equation, C is the speed of light, and W _swath is the width of the surveying zone;

Equation (4) is the image signal-to-noise ratio constraint equation (radar equation), K is the Boltzmann constant, T ₀ is the absolute temperature, D _r =C/2B is the distance resolution, λ=C/f _c is the radar working Wavelength, P _av =P _t ×τ×PRF is the average power, NEσ0 represents the noise equivalent backscattering coefficient, Thereshold represents the judgment threshold of NEσ0, and the typical value of Thereshold is -30dB. Usually, NEσ0 can be used to measure the SNR of the final SAR image. When NEσ0 is less than the decision threshold Thereshold, it can be considered that the final SAR image SNR meets the design requirements; when NEσ0 is greater than the decision threshold Thereshold, it is considered that the target is in the final SAR image drowned in the noise, unrecognizable. Therefore, when NEσ0 exceeds the threshold Thereshold within a given range of incident angles, it is determined that the set of "system operating parameters" is not feasible, and feedback is given to the user for modification.

Equation (5) is the width equation of the surveying swath, where W1 is the design lower limit of the swath width, and W2 is the upper design limit of the swath width. When the width of the surveying swath W _swath does not meet the user restriction condition W ₁ ≤ W _swath ≤ W ₂ within the given incident angle range, it is determined that the set of "system operating parameters" is not feasible, and feedback to the user for modification;

When NEσ0 does not exceed the threshold Thereshold within a given incident angle range, and the swath width W _swath satisfies the user restriction condition W ₁ ≤ W _swath ≤ W ₂ , it is determined that the set of "system operating parameters" is feasible.

Step D: Receive the "transmission signal parameter" set input by the user, perform transmission signal predistortion correction, export the transmission signal predistortion digital waveform file, and send the transmission signal predistortion digital waveform file as a parameter file to the baseband signal generation module;

The "transmission signal parameters" set describes and uniquely determines the waveform of the baseband transmission signal, including signal encoding method, signal bandwidth B, signal pulse width τ, D/A sampling frequency F _s and other parameters. Among them, the signal encoding methods include QPSK, 2PSK, QAM, Chirp encoding and other methods; when the "transmission signal parameter" set and the system operating frequency f _c are determined, use the baseband signal generation module, quadrature modulation up-conversion module and signal observation equipment Execute sub-steps D1 to D5, perform baseband transmit signal waveform pre-distortion correction, export the pre-distortion digital waveform file, and perform parameter configuration on the baseband signal generation module;

This step D can comprise again:

Sub-step D1, divide the signal bandwidth into multiple discrete frequency points f _p = pΔf according to the signal bandwidth and D/A sampling frequency parameters in the "transmission signal parameters" set, where p∈[1,P] represents the pth frequency point; for a discrete frequency point f _p , generate the ideal continuous wave signal digital waveform of the frequency point;

Sub-step D2, for the ideal continuous wave signal digital waveform corresponding to the frequency point _fp obtained in sub-step D1, the baseband signal generation hardware module converts it into an analog signal through DA synthesis, and uses it as the positive signal of the quadrature modulation up-conversion hardware module AC modulation input, output modulated RF signal;

In sub-step D3, the modulated RF signal obtained in sub-step D2 is measured using signal observation equipment, such as an oscilloscope and a spectrum analyzer, and its measured value is used as the measured value γ(f _p ) of the discrete frequency point;

Sub-step D4, traverse all the frequency points of p∈[1,P] in turn, execute the process of D1～D3, and obtain the measurement [γ(f ₁ ),...,γ(f _p ),...γ(f _P )], And by comparing with the amplitude and phase of the ideal waveform, the amplitude predistortion correction value [A(f ₁ ),...,A(f _p ),...A(f _P )] and phase correction value of each frequency point are calculated

In sub-step D5, the result obtained in sub-step D4 is used as the correction value. First, the digital waveform of the ideal baseband transmission signal is generated according to the set of "transmission signal parameters", and its spectrum s(f _p ) is obtained through Fourier transform, and the correction value is used for pre-distortion Amplitude and Phase Correction Finally, the inverse Fourier transform is performed on the predistortion corrected spectrum sequence to obtain the predistortion digital waveform file of the transmitted signal, which is exported as the input parameter file of the baseband signal generation module.

Step E: sending each control parameter of the system working parameter set obtained in step C to the corresponding hardware module; sending the transmitted signal predistortion digital waveform file obtained in step D to the baseband signal generation module;

This step includes:

Sub-step E1, sending the working frequency parameter f _c to the quadrature modulation up-conversion module as its input parameter;

Sub-step E2, sending the parameter N of the number of transmitting channels to the channel switching module at the transmitting end as its input parameter;

Sub-step E3, send the parameter M of the number of receiving channels to the channel switching module at the receiving end as its input parameter;

Sub-step E4, sending the operating frequency parameter f _c and the receiver noise figure parameter F _n to the receiver down-conversion module as its input parameters;

Sub-step E5, sending the pulse width parameter τ, the sampling frequency parameter f _s , and the pulse repetition frequency parameter PRF to the AD sampling and storage module as its input parameters;

Sub-step E6, sending the receiver down-conversion local oscillator frequency parameter _f0 to the frequency source module as its input parameter;

Sub-step E7, sending the pulse repetition frequency parameter PRF to the timer module as its input parameter; and

Sub-step E8, using the transmitted signal predistortion digital waveform file obtained in step D as a parameter file, and sending it to the baseband signal generation module;

Step F, instruct each device to perform parameter configuration according to the input control parameters, and receive the feedback of operating parameters from the hardware device, and perform "system verification" to eliminate errors and conflicts in parameter setting;

This step includes:

Sub-step F1, the control device reads the feedback device parameter set F(β ₁ ,...,β _q ,...β _Q ) from each hardware module, where β _q represents the user variable fed back by the qth device, q∈[ 1, Q], Q represents the maximum number of devices that the control device can control;

Sub-step F2, compare the feedback device parameter set F(β ₁ ,…,β _q ,…β _Q ) with the control parameter set f(α ₁ ,…,α _q ,…α _Q ) sent to the device, where α _q represents the control parameter sent by the control device to the qth device;

Sub-step F3, processing according to the comparison result, including:

Sub-step F3a, when the device q has no feedback parameters, it is determined that the device has not successfully communicated, and the user is fed back to connect;

Sub-step F3b, when the feedback parameter β _q of the device q is not equal to the control parameter α _q sent to it, it is determined that the parameter setting of the device is wrong, and the user is fed back to modify it;

Sub-step F3c, when all devices have feedback parameters, and the feedback parameters are equal to the control parameters sent to them, it is determined that all devices have successfully communicated and the parameter settings are correct, and perform step G;

Step G, the control device sends a startup command to each hardware device to start the broadband multi-channel coherent radar imaging simulation.

This step G can comprise again:

Sub-step G1, sending a start command to the timer module to make it output a timing pulse;

Sub-step G2, sending a startup command to the frequency source module to make it output the external sampling clock signal and the down-converted local oscillator signal of the receiver;

Sub-step G3, sending a starting command to the baseband signal generation module, so that it receives the timing pulse output by the timer module and the external sampling clock signal output by the frequency source module, and outputs the baseband transmission signal and envelope signal;

Sub-step G4, sending a startup instruction to the quadrature modulation up-conversion module, so that it receives the baseband transmit signal and the envelope signal output by the baseband signal generation module, performs quadrature modulation, and outputs the modulated radio frequency signal;

Sub-step G5, send a starting command to the channel switching module of the transmitting end, so that it receives the switch strobe pulse output by the timer module, performs channel switching, switches the modulated RF signal to the transmitter power amplifier of the corresponding transmitting channel, and passes the transmitting Antenna radiates out;

Sub-step G6, sending an instruction to the channel switching module of the receiving end, so that it receives the switch gating signal pulse output by the timer module, and performs channel switching on the radio frequency signal received by the receiving antenna of the corresponding receiving channel;

Sub-step G7, send a startup command to the down-conversion module of the receiver, so that it receives the RF signal output from the channel switching module at the receiving end and the down-converted local oscillator signal output by the frequency source module, and performs RF preselection and low-noise amplification on the RF signal , down conversion frequency mixing and intermediate frequency filtering, amplification, the output is intermediate frequency signal;

Sub-step G8, send a start command to the AD sampling and storage module, make it receive the timing pulse output by the timer module and the external sampling clock signal output by the frequency source module, sample the intermediate frequency signal output by the receiver down-conversion module, and save into the original echo sampling data.

So far, the control method of the BMCIRS system in this embodiment has been described in detail with reference to the accompanying drawings. According to the above description, those skilled in the art should have a clear understanding of the control method of the BMCIRS system of the present invention.

In addition, the interfaces and standards used in the above control methods are not limited to the various specific forms mentioned in the implementation, and those skilled in the art can simply replace them with familiar ones, for example:

(1) The IO communication connection and control of the control device to the hardware module can be not only through the LXI (LAN) interface bus, but also in the form of GPIB, VXI, and PXI interface buses, as long as the hardware device has the underlying driver of the corresponding interface bus;

(2) Custom hardware modules including receiver down-conversion module, AD sampling and storage module application program interface protocol can be used in addition to VISA standard protocol of general instruments, TCP/IP protocol, UART protocol can also be used instead, as long as according to the corresponding The standard communication protocol standard provides users with a programming control interface to control the device.

In summary, the present invention provides a BMCIRS system control method that can flexibly and effectively control hardware modules for data collection. This method realizes complex and continuous microwave imaging experiment data acquisition in multiple modes of BMCIRS system through unique parameter design, setting and feedback verification methods, and develops microwave imaging scattering mechanism, imaging system and signal Dealing with and other related issues provides the basis for research.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (16)

1. A broadband multi-channel coherent radar imaging BMCIRS system is characterized in that, comprising: The baseband signal generation module includes at least one arbitrary waveform generator, and each arbitrary waveform generator occupies one transmission channel; The quadrature modulation up-conversion module includes at least one vector microwave signal source, each vector microwave signal source occupies a transmission channel, and is used in conjunction with an arbitrary waveform generator that constitutes a baseband signal generation module at the channel; The channel switching module at the transmitting end includes a multi-channel microwave switch device. The input common end of the multi-channel microwave switch device is connected to the modulated radio frequency pulse signal output by the quadrature modulation up-conversion module, and the multiple output ports are respectively connected and the radio frequency signal Output to different transmitter power amplifier modules; The channel switching module at the receiving end includes a multi-channel microwave switch device, multiple input terminals of the multi-channel microwave switch device are connected to different receiving antennas, and the output common terminal is connected to the receiver down-conversion module; The receiver down-conversion module includes at least one multi-channel down-converter, its first input terminal is connected to the output terminal of the frequency source module, its second input terminal is connected to the output common terminal of the receiver channel switching module, and its output terminal Connect to AD sampling and storage module; The AD sampling and storage module is used for high-speed data acquisition and recording of the intermediate frequency signal output by the receiver down-conversion module under the trigger of the external timer, using the external sampling clock signal output by the frequency source module as the sampling clock to form the required the original echo data; The frequency source module includes at least two analog signal generators, wherein one analog signal generator provides local oscillator signal input for the receiver down-conversion module, and the other analog signal generator is the baseband signal generation module and AD sampling and storage The module provides external sampling clock signal; The timer module is used to provide trigger input pulses for the baseband signal generation module and the AD sampling and storage module, and to provide switch gating signals for the channel switching module at the transmitting end and the channel switching module at the receiving end; and Control equipment, together with the above-mentioned baseband signal generation module, quadrature modulation up-conversion module, transmitter channel switch module, receiver channel switch module, receiver down-conversion hardware module, AD sampling and storage hardware module, frequency source module, timer module It is used to carry out broadband multi-channel coherent radar imaging simulation through coordinated operation after configuring the above hardware devices. 2. BMCIRS system according to claim 1, is characterized in that: The baseband signal generation module, quadrature modulation up-conversion module, transmitter channel switch module, receiver channel switch module, frequency source module, and timer module conform to the virtual instrument software framework VISA of National Instruments NI Corporation of the United States; The control device performs IO communication connection with the above-mentioned other hardware modules through the interface bus LXI or LAN, and controls them through the VISA application program interface. 3. BMCIRS system according to claim 1, is characterized in that: In the baseband signal generating module, the arbitrary waveform generator is used to convert the external sampling clock signal output by the frequency source module into Simulate baseband transmit signal waveform and corresponding pulse envelope signal; In the quadrature modulation up-conversion module, the vector microwave signal source is used to perform quadrature modulation and pulse modulation on the analog baseband transmit signal waveform and the corresponding pulse envelope signal output by its matching arbitrary waveform generator, to generate Modulate RF pulse signal and its pulse envelope. 4. BMCIRS system according to claim 3, is characterized in that: In the channel switching module at the transmitting end, the input common terminal of the multi-channel microwave switchgear is connected to the modulated radio frequency pulse signal output by the quadrature modulation up-conversion module, and the multiple output terminals are respectively connected and output the radio frequency signal to different Transmitter power amplifier module, when working, according to the control instruction sent by the receiving control device, the switch gating signal output by the timer module is used as the trigger signal to switch the different channels of the radio frequency signal in the microwave switch device, and the radio frequency signal is turned on to Different transmitter power amplifiers perform power amplification and radiate out through the transmitting antenna; In the channel switching module at the receiving end, multiple input terminals of the multi-channel microwave switching device are connected to different receiving antennas, and the output common terminal is connected to the receiver down-conversion module. When working, according to the received control command sent by the control device , using the switch strobe signal output by the timer module as a trigger signal to switch the paths of the received signals at different antennas in the microwave switch equipment, and the radio frequency signal is time-divided and turned on to the receiver down-conversion module. 5. BMCIRS system according to claim 4, is characterized in that: In the receiver down-conversion module, the multi-channel down-converter uses the frequency source module to output the local oscillator signal as the mixing signal, and performs radio frequency preselection on the radio frequency signal output by the channel switching module at the receiving end and received by the receiving antenna. Noise amplification, down-conversion frequency mixing and intermediate frequency filtering, amplification, the output is intermediate frequency signal, which is used as the input of AD sampling and storage hardware module; The AD sampling and storage module is used for setting the parameters of the control device, under the trigger of an external timer, using the external sampling clock signal output by the frequency source module as the sampling clock, and performing the intermediate frequency signal output by the receiver down-conversion module High-speed data acquisition and recording, and finally form the required original echo data. 6. BMCIRS system according to claim 5, is characterized in that: In the frequency source module, one analog signal generator of the at least two analog signal generators provides local oscillator signal input for the receiver down-conversion module, and the other analog signal generator is the baseband signal generation module and AD sampling Provide external sampling clock signal with the storage module; The timer module is used to provide trigger input pulses for the baseband signal generation module and the AD sampling and storage module on the one hand, and provide switch gating signals for the channel switching module at the transmitting end and the channel switching module at the receiving end on the other hand. 7. a control method of BMCIRS system, for controlling the BMCIRS system described in any one of claims 1 to 6, it is characterized in that, carried out by described control equipment, comprising: Step A: Receive the system working mode information input by the user, that is, the number N of transmission channels and the number M of reception channels of the system; Step B: configure and initialize the corresponding hardware devices according to the system working mode information; Step C: Receive the system working parameter set input by the user, conduct parameter feasibility analysis on the parameters in the system working parameter set through the constraint equation group, and feed back to the user for modification until the system working parameter set meets the requirements; Step D: Receive the "transmission signal parameter" set input by the user, perform transmission signal predistortion correction, export the transmission signal predistortion digital waveform file, and send the transmission signal predistortion digital waveform file as a parameter file to the baseband signal generation module; Step E: Send each control parameter of the system working parameter set to the corresponding hardware module; send the transmitted signal pre-distorted digital waveform file to the baseband signal generation module; Step F, instructing each device to perform parameter configuration according to the input control parameters, and receiving feedback from the hardware device on operating parameters, and performing system verification, so as to eliminate errors and conflicts in parameter setting; and Step G, the control device sends a startup command to each hardware device to start the broadband multi-channel coherent radar imaging simulation. 8. BMCIRS system control method according to claim 7, is characterized in that, when the selected system operation pattern in the described step A is single sending and single receiving, namely N=1, when M=1, described step B include: Sub-step B1a, configure a waveform generator to form a baseband signal generation module, and send instructions to it to initialize it; In sub-step B1b, configure a vector microwave signal source matched with the above-mentioned waveform generator to form a quadrature modulation up-conversion module, and send instructions to it to initialize it; Sub-step B1c, configuring a multi-channel down-converter with K channels to form a receiver down-conversion module, and sending an instruction to it to activate any one of its K channels as a receiving channel; Sub-step B1d, configure a multi-channel high-speed data acquisition and recorder with L channels to form an AD sampling and storage module, and send an instruction to it to activate any one of its L channels as a sampling channel; In sub-step B1e, configure two analog signal generators as external sampling clock frequency sources and down-conversion local oscillator frequency sources to form frequency source modules, and send instructions to them to initialize them; and Sub-step B1f, configure a pulse signal generator to form a timer module, and send instructions to it to initialize it. 9. BMCIRS system control method according to claim 7, is characterized in that, when the selected system work pattern in the described step A is single sending and multiple receiving, namely N=1, when M≥2, described step B include: Sub-step B2a, configure an arbitrary waveform generator to form a baseband signal generation module, and send instructions to it to initialize it; In sub-step B2b, configure a vector microwave signal source to form a quadrature modulation up-conversion module, and send instructions to it to initialize it; Sub-step B2c, configure a multi-channel down-converter with K channels to form a receiver down-conversion module, and send instructions to it. When M≤K, make its M channels activated as receiving channels. When In the case of M>K, all K channels are activated as receiving channels; Sub-step B2d, configure a multi-channel high-speed data acquisition and recorder with L channels to form an AD sampling and storage module, and send instructions to it, and when M≤L, make its M channels activated as sampling channels, when M>L, all L channels are activated as sampling channels; Sub-step B2e, configure a microwave switch network device to form a channel switching module at the receiving end, and send instructions to it to initialize it; In sub-step B2f, configure two analog signal generators as external sampling clock frequency sources and down-conversion local oscillator frequency sources to form frequency source modules, and send instructions to them to initialize them; and Sub-step B2g, configure a pulse signal generator to form a timer module, and send instructions to it to initialize it; perform step C. 10. BMCIRS system control method according to claim 7, is characterized in that, when the selected system working pattern in the said step A is multiple sending and single receiving, that is, when N≥2, M=1, said step B include: Sub-step B3a, configure two arbitrary waveform generators to form the two channels of the baseband signal generation module, and send instructions to them to initialize them; In sub-step B3b, configure two vector microwave signal sources to form two channels of the quadrature modulation up-conversion module, and send instructions to them to initialize them; when the system operation mode information N=2 input by the user, execute step B3d; Sub-step B3c, configuring a microwave switch network device to form a channel switching module at the transmitter, and sending instructions to it to initialize it; Sub-step B3d, configuring a multi-channel down-converter with the number of channels K to form a receiver down-conversion module, and sending an instruction to it to activate any one of its K channels as a receiving channel; Sub-step B3e, configure a multi-channel high-speed data acquisition and recorder with L channels to form an AD sampling and storage module, and send an instruction to it to activate any one of its L channels as a sampling channel; In sub-step B3f, configure two analog signal generators as external sampling clock frequency sources and down-converted local oscillator frequency sources to form frequency source modules, and send instructions to them to initialize them; and Sub-step B3g, configure a pulse signal generator to form a timer module, and send instructions to it to initialize it. 11. BMCIRS system control method according to claim 7, is characterized in that, when the selected system working pattern in the said step A is multi-send and single-receive, that is, when N≥2, M=1, said step B include: Sub-step B4a, configure two arbitrary waveform generators to form two channels of the baseband signal generation module, and send instructions to them to initialize them; In sub-step B4b, configure two vector microwave signal sources to form two channels of the quadrature modulation up-conversion module, and send instructions to them to initialize them; when the system operation mode information N=2 input by the user, execute step B4d; Sub-step B4c, configuring a microwave switch network device to form a channel switching module at the transmitter, and sending instructions to it to initialize it; Sub-step B4d, configure a multi-channel down-converter with the number of channels K to form a receiver down-conversion module, and send instructions to it, when M≤K, make its M channels activated as receiving channels, when In the case of M>K, all K channels are activated as receiving channels; Sub-step B4e, configure a multi-channel high-speed data acquisition and recorder with L channels to form an AD sampling and storage module, and send instructions to it, and when M≤L, make its M channels activated as sampling channels, when M>L, all L channels are activated as sampling channels; Sub-step B4f, configure a microwave switch network device to form a channel switching module at the receiving end, and send instructions to it to initialize it; In sub-step B4g, configure two analog signal generators as external sampling clock frequency sources and down-converted local oscillator frequency sources to form a frequency source module, and send instructions to it to initialize it; and Sub-step B4h, configure a pulse signal generator to form a timer module, and send instructions to it to initialize it. 12. BMCIRS system control method according to claim 7, is characterized in that, in described step C: The system operating parameters in the system operating parameter set include system operating frequency f _c , bandwidth B, pulse width τ, sampling frequency f _s , pulse repetition frequency PRF, peak transmit power P _t , antenna gain G, azimuth beam width θ _a , Elevation beam width θ _c , platform velocity V, platform height H, incident angle range Ф∈[Ф ₁ , Ф ₂ ], receiver noise figure F _n , system loss L _n , receiver down-conversion local oscillator frequency f ₀ , intermediate frequency Output frequency f _I , number of transmitting channels N and number of receiving channels M; The set of constraint equations includes: $\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; ></span>\mathrm{<span\; class="notranslate">\; B</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; PRF</span>}<span\; class="notranslate">\; ></span>\frac{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; V</span>}}{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; PRF</span>}<span\; class="notranslate">\; <</span>\frac{\mathrm{<span\; class="notranslate">\; C</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; swath</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; \&Phi;</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>\\ {\mathrm{<span\; class="notranslate">\; NE\&sigma;</span>}}^{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; =</span>\frac{{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 3</span>}}{\mathrm{<span\; class="notranslate">\; KT</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; R</span>}}^{\mathrm{<span\; class="notranslate">\; 3</span>}}{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; V</span>}}{{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; av</span>}}{\mathrm{<span\; class="notranslate">\; G</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}^{\mathrm{<span\; class="notranslate">\; 3</span>}}{\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}}}\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; \&Phi;</span>}<span\; class="notranslate">\; \&le;</span>\mathrm{<span\; class="notranslate">\; Threshold</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>\\ {\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; <</span>{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; swath</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; [</span>\mathrm{<span\; class="notranslate">\; the\; tan</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&Phi;</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; the\; tan</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&Phi;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span><span\; class="notranslate">\; <</span>{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>\end{array}\right.$ Among them, formula (1) is the Nyquist sampling constraint equation; Equation (2) is the azimuth fuzzy constraint equation, where: D is the azimuth dimension of the antenna; Equation (3) is the distance fuzzy constraint equation, where: C is the speed of light, W _swath is the width of the surveying zone; Equation (4) is the image signal-to-noise ratio constraint equation, where: K is the Boltzmann constant, T ₀ is the absolute temperature, D _r =C/2B is the distance resolution, λ=C/f _c is the radar operating wavelength, P _αv =P _t ×τ×PRF is the average power, NEσ0 represents the noise equivalent backscattering coefficient, Thereshold represents the decision threshold of NEσ0; Equation (5) is the width equation of the swath, where: W1 is the design lower limit of the swath width, and W2 is the upper design limit of the swath width. 13. BMCIRS system control method according to claim 7, is characterized in that, in the described step D: The set of "transmission signal parameters" includes signal encoding method, signal bandwidth B, signal pulse width τ, D/A sampling frequency F _s , Said step D comprises: Sub-step D1, divide the signal bandwidth into multiple discrete frequency points f _p = pΔ according to the signal bandwidth and D/A sampling frequency parameters in the "transmission signal parameters" set, where p∈[1,P] represents the pth frequency point; for a discrete frequency point f _p , generate the ideal continuous wave signal digital waveform of the frequency point; Sub-step D2, for the ideal continuous wave signal digital waveform corresponding to the frequency point _fp obtained in sub-step D1, the baseband signal generation hardware module converts it into an analog signal through DA synthesis, and uses it as the positive signal of the quadrature modulation up-conversion hardware module AC modulation input, output modulated RF signal; In sub-step D3, the modulated RF signal obtained in sub-step D2 is measured using signal observation equipment, and its measured value is used as the measured value γ(f _p ) of the discrete frequency point; Sub-step D4, traverse all the frequency points of p∈[1,P] in turn, execute the process of D1～D3, and obtain the measurement [γ(f ₁ ),...,γ(f _p ),...γ(f _P )], And by comparing with the amplitude and phase of the ideal waveform, the amplitude predistortion correction value [A(f ₁ ),...,A(f _p ),...A(f _P )] and phase correction value of each frequency point are calculated

In sub-step D5, the result obtained in sub-step D4 is used as the correction value. First, the digital waveform of the ideal baseband transmission signal is generated according to the set of "transmission signal parameters", and its spectrum s(f _p ) is obtained through Fourier transform, and the correction value is used for pre-distortion Amplitude and Phase Correction

Finally, the inverse Fourier transform is performed on the predistortion corrected spectrum sequence to obtain the predistortion digital waveform file of the transmitted signal, which is exported as the input parameter file of the baseband signal generation module. 14. BMCIRS system control method according to claim 7, is characterized in that, described step E comprises: Sub-step E1, sending the working frequency parameter f _c to the quadrature modulation up-conversion module as its input parameter; Sub-step E2, sending the parameter N of the number of transmitting channels to the channel switching module at the transmitting end as its input parameter; Sub-step E3, sending the parameter M of the number of receiving channels to the channel switching module at the receiving end as its input parameter; Sub-step E4, sending the operating frequency parameter f _c and the receiver noise figure parameter F _n to the receiver down-conversion module as its input parameters; Sub-step E5, sending the pulse width parameter τ, the sampling frequency parameter f _s , and the pulse repetition frequency parameter PRF to the AD sampling and storage module as its input parameters; Sub-step E6, sending the receiver down-conversion local oscillator frequency parameter _f0 to the frequency source module as its input parameter; Sub-step E7, sending the pulse repetition frequency parameter PRF to the timer module as its input parameter; and In sub-step E8, the transmit signal predistortion digital waveform file obtained in step D is used as a parameter file and sent to the baseband signal generation module. 15. BMCIRS system control method according to claim 7, is characterized in that, described step F comprises: Sub-step F1, the control device reads the feedback device parameter set F(β ₁ ,...,β _q ,...β _Q ) from each hardware module, where β _q represents the user variable fed back by the qth device, q∈[ 1, Q], Q represents the maximum number of devices that the control device can control; Sub-step F2, compare the feedback device parameter set F(β ₁ ,…,β _q ,…β _Q ) with the control parameter set f(α ₁ ,…,α _q ,…α _Q ) sent to the device, where α _q represents the control parameter sent by the control device to the qth device; Sub-step F3, processing according to the comparison result, including: Sub-step F3a, when the device q has no feedback parameters, it is determined that the device has not successfully communicated, and the user is fed back to connect; Sub-step F3b, when the feedback parameter β _q of the device q is not equal to the control parameter α _q sent to it, it is determined that the parameter setting of the device is wrong, and the user is fed back to modify it; and Sub-step F3c, when all devices have feedback parameters, and the feedback parameters are equal to the control parameters sent to them, it is determined that all devices have successfully communicated and the parameter settings are correct, and step G is performed. 16. BMCIRS system control method according to claim 7, is characterized in that, described step G comprises: Sub-step G1, sending a start command to the timer module to make it output a timing pulse; Sub-step G2, sending a startup command to the frequency source module to make it output the external sampling clock signal and the down-converted local oscillator signal of the receiver; Sub-step G3, sending a starting command to the baseband signal generation module, so that it receives the timing pulse output by the timer module and the external sampling clock signal output by the frequency source module, and outputs the baseband transmission signal and envelope signal; Sub-step G4, sending a startup instruction to the quadrature modulation up-conversion module, so that it receives the baseband transmit signal and the envelope signal output by the baseband signal generation module, performs quadrature modulation, and outputs the modulated radio frequency signal; Sub-step G5, send a starting command to the channel switching module of the transmitting end, so that it receives the switch strobe pulse output by the timer module, performs channel switching, switches the modulated RF signal to the transmitter power amplifier of the corresponding transmitting channel, and passes the transmitting Antenna radiates out; Sub-step G6, sending an instruction to the channel switching module of the receiving end, so that it receives the switch gating signal pulse output by the timer module, and performs channel switching on the radio frequency signal received by the receiving antenna of the corresponding receiving channel; Sub-step G7, send a startup command to the down-conversion module of the receiver, so that it receives the RF signal output from the channel switching module at the receiving end and the down-converted local oscillator signal output by the frequency source module, and performs RF preselection and low-noise amplification on the RF signal , down conversion frequency mixing and intermediate frequency filtering, amplification, the output is intermediate frequency signal; Sub-step G8, send a start command to the AD sampling and storage module, make it receive the timing pulse output by the timer module and the external sampling clock signal output by the frequency source module, sample the intermediate frequency signal output by the receiver down-conversion module, and save into the original echo sampling data.

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