A target clutter simulation device, method and radar test device

Abstract

The present invention discloses a target clutter simulation device, method and radar test device, which relate to the field of radar training and testing. The device comprises: a switch filter module, a frequency conversion module, an intermediate frequency digital frequency storage module and a control module, wherein the switch filter module, the frequency conversion module and the intermediate frequency digital frequency storage module are connected in sequence, and the control module is respectively connected to the switch filter module, the frequency conversion module and the intermediate frequency digital frequency storage module; the target clutter simulation device of the present scheme realizes wide-band target interference simulation, and can realize radar test measurement, which is more helpful for radar simulation training.

Description

Technical Field

[0001] The present invention relates to the field of radar training and testing, and in particular to a target clutter simulation device and method, and a radar testing device. Background Art

[0002] Radars of different frequency bands all have training requirements, so it is necessary to develop target simulation equipment. Currently, most target simulation equipment is designed for a certain type of radar, so the target simulation equipment is only designed for a specific frequency band and can only be applied to up and down conversion modules with a specific frequency band. It cannot meet the training requirements of radars of different frequency bands. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a target clutter simulation device, method and radar testing device in view of the deficiencies in the prior art.

[0004] The technical solution of the present invention to solve the above technical problems is as follows:

[0005] A target clutter simulation device comprises: a switch filter module, a frequency conversion module, an intermediate frequency digital frequency storage module and a control module;

[0006] The switch filter module, the frequency conversion module and the intermediate frequency digital frequency storage module are connected in sequence;

[0007] The control module is respectively connected to the switch filter module, the frequency conversion module and the intermediate frequency digital frequency storage module;

[0008] The switch filter module is used to receive a first radio frequency signal to be processed, and perform a first filtering process on the first radio frequency signal according to a first control parameter sent by the control module to obtain a first radio frequency signal;

[0009] The frequency conversion module is used to perform a first frequency conversion process on the first radio frequency signal according to the second control parameter sent by the control module to obtain an intermediate frequency signal;

[0010] The intermediate frequency digital frequency storage module is used to perform target signal simulation processing on the intermediate frequency signal according to the third control parameter issued by the control module;

[0011] The frequency conversion module is further used to perform a second frequency conversion process on the preset processed intermediate frequency signal according to the second control parameter to obtain a second radio frequency signal;

[0012] The switch filtering module is further configured to perform a second filtering process on the second radio frequency signal according to the first control parameter to obtain a target signal.

[0013] The beneficial effects of the present invention are as follows: the present solution realizes wide-band target interference simulation through a target clutter simulation device including a switch filter module, a frequency conversion module, an intermediate frequency digital frequency storage module and a control module, and can realize radar test measurement, which is more helpful for radar simulation training. The present solution solves the problem of single frequency band and repeated development of target clutter simulation equipment in traditional methods. The present solution has a high degree of generalization and standardization, solves the problem of repeated development of target clutter simulation equipment for radars in different frequency bands, and adds radar parameter measurement function, with richer functions.

[0014] Further, the switch filter module includes: an uplink switch filter module and a downlink switch filter module;

[0015] The downlink switch filtering module is used to receive a first radio frequency signal to be processed, and perform amplitude limiting and bandpass filtering of a preset frequency band on the first radio frequency signal according to a first control parameter to obtain a first radio frequency signal;

[0016] The uplink switch filtering module is used to filter, amplify and attenuate the second radio frequency signal according to the first control parameter to obtain a target signal.

[0017] The beneficial effect of adopting the above further scheme is that the scheme can control the target clutter simulation device to work in the corresponding working frequency band by limiting and filtering the received signal through the downlink switch filter module. The RF signal is filtered, amplified and attenuated through the uplink switch filter module.

[0018] Further, the downlink switch filter module includes: a limiter, a first switch, a first bandpass filter group and a second switch;

[0019] The limiter, the first switch, the first bandpass filter group and the second switch are connected in sequence;

[0020] The first bandpass filter group includes a plurality of bandpass filters of different frequency bands, and the bandpass filter of each frequency band is connected to the first switch and the second switch respectively.

[0021] The beneficial effect of adopting the above further scheme is that: this scheme limits and filters the received signal through the downlink switch filter module, and can control the target clutter simulation device to operate in the corresponding working frequency band.

[0022] Further, the uplink switch filter module includes: a third switch, a second bandpass filter group, a fourth switch, an amplifier and a programmable attenuator;

[0023] The third switch, the second bandpass filter group, the fourth switch, the amplifier and the programmable attenuator are connected in sequence;

[0024] The programmable attenuator is connected to the third switch and the fourth switch respectively;

[0025] The second band-pass filter group includes a plurality of band-pass filters of different frequency bands, and the band-pass filter of each frequency band is connected to the third switch and the fourth switch respectively.

[0026] The beneficial effect of adopting the above further scheme is: this scheme filters, amplifies and attenuates the radio frequency signal through the uplink switch filter module, and determines the attenuation range of the programmable attenuation according to the range of the simulated target amplitude fluctuation.

[0027] Further, the frequency conversion module includes: an up-conversion module and a down-conversion module;

[0028] The down-conversion module is used to perform down-conversion processing on the first radio frequency signal according to the second control parameter to obtain an intermediate frequency signal;

[0029] The up-conversion module is used to perform up-conversion processing on the preset processed intermediate frequency signal according to the second control parameter to obtain a second radio frequency signal.

[0030] The beneficial effect of adopting the above further scheme is: this scheme realizes frequency conversion processing of the intermediate frequency signal through the frequency conversion module, and controls the target clutter simulation device to operate in the corresponding working frequency band.

[0031] Further, the control module includes: control software and a display and control module; the control software is used to receive the target simulation parameters, calculate the first control parameter, the second control parameter and the third control parameter according to the target simulation parameters, and output them to the display and control module;

[0032] The display and control module is used to display the first control parameter, the second control parameter and the third control parameter.

[0033] The beneficial effects of adopting the above further scheme are: this scheme realizes the calculation and parameter measurement functions of the target simulation parameters through the control module; and realizes the display of the feedback parameters and monitoring data through the display control module.

[0034] Another technical solution of the present invention to solve the above technical problems is as follows:

[0035] A target clutter simulation method, comprising:

[0036] receiving a first radio frequency signal to be processed, and performing a first filtering process on the first radio frequency signal according to a first control parameter sent by a control module to obtain a first radio frequency signal;

[0037] Performing a first frequency conversion process on the first radio frequency signal according to the second control parameter sent by the control module to obtain an intermediate frequency signal;

[0038] Performing target signal simulation processing on the intermediate frequency signal according to the third control parameter issued by the control module;

[0039] Performing a second frequency conversion process on the preset processed intermediate frequency signal according to the second control parameter to obtain a second radio frequency signal;

[0040] Perform a second filtering process on the second radio frequency signal according to the first control parameter to obtain a target signal.

[0041] The beneficial effects of the present invention are as follows: the present solution realizes wide-band target interference simulation by executing the target clutter simulation method in the target clutter simulation device, and can realize radar test measurement, which is more helpful for radar simulation training. The present solution solves the problem of single frequency band and repeated development of target clutter simulation equipment in traditional methods. The present solution has a high degree of generalization and standardization, solves the problem of repeated development of target clutter simulation equipment for radars in different frequency bands, and adds radar parameter measurement function, with richer functions.

[0042] Further, the receiving a first radio frequency signal to be processed, performing a first filtering process on the first radio frequency signal according to a first control parameter, and obtaining the first radio frequency signal specifically includes:

[0043] According to the first control parameter, the first radio frequency signal is subjected to amplitude limiting and band-pass filtering of a preset frequency band to obtain a first radio frequency signal;

[0044] The performing a second filtering process on the second radio frequency signal according to the first control parameter to obtain the target signal specifically includes: performing filtering, amplifying and attenuating processes on the second radio frequency signal according to the first control parameter to obtain the target signal.

[0045] The beneficial effect of adopting the above further scheme is that the scheme can control the target clutter simulation device to work in the corresponding working frequency band by limiting and filtering the received signal through the downlink switch filter module. The RF signal is filtered, amplified and attenuated through the uplink switch filter module.

[0046] Further, performing a first frequency conversion process on the first radio frequency signal according to the second control parameter to obtain an intermediate frequency signal specifically includes:

[0047] Performing down-conversion processing on the first radio frequency signal according to a second control parameter to obtain an intermediate frequency signal;

[0048] The performing a second frequency conversion process on the preset processed intermediate frequency signal according to the second control parameter to obtain the second radio frequency signal specifically includes:

[0049] The preset processed intermediate frequency signal is up-converted according to the second control parameter to obtain a second radio frequency signal.

[0050] The beneficial effect of adopting the above further scheme is: this scheme realizes frequency conversion processing of the intermediate frequency signal through the frequency conversion module, and controls the target clutter simulation device to operate in the corresponding working frequency band.

[0051] Furthermore, it also includes: receiving a target simulation parameter, calculating a first control parameter, a second control parameter and a third control parameter according to the target simulation parameter, and outputting the first control parameter, the second control parameter and the third control parameter to the display and control module;

[0052] The first control parameter, the second control parameter, and the third control parameter are displayed.

[0053] The beneficial effects of adopting the above further scheme are: this scheme realizes the calculation and parameter measurement functions of the target simulation parameters through the control module; and realizes the display of the feedback parameters and monitoring data through the display control module.

[0054] Another technical solution of the present invention to solve the above technical problems is as follows:

[0055] A radar testing device comprises: a target clutter simulation device adopting any one of the above schemes.

[0056] The beneficial effects of the present invention are as follows: the present solution realizes wide-band target interference simulation through a target clutter simulation device including a switch filter module, a frequency conversion module, an intermediate frequency digital frequency storage module and a control module, and can realize radar test measurement, which is more helpful for radar simulation training. The present solution solves the problem of single frequency band and repeated development of target clutter simulation equipment in traditional methods. The present solution has a high degree of generalization and standardization, solves the problem of repeated development of target clutter simulation equipment for radars in different frequency bands, and adds radar parameter measurement function, with richer functions.

[0057] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 A structural block diagram of a target clutter simulation device provided by an embodiment of the present invention

[0059] Figure 2 A schematic flow chart of a target clutter simulation method provided by an embodiment of the present invention;

[0060] Figure 3 A schematic diagram of the structure of a target clutter simulation device provided by other embodiments of the present invention;

[0061] Figure 4 A schematic diagram of the structure of a control module provided for another embodiment of the present invention;

[0062] Figure 5 A schematic diagram of a control flow of control software provided for other embodiments of the present invention;

[0063] Figure 6 A schematic diagram of the structure of a downlink switch filter module provided by other embodiments of the present invention;

[0064] Figure 7 A schematic diagram of the structure of an uplink switch filter module provided by other embodiments of the present invention;

[0065] Figure 8 A schematic structural diagram of a down-conversion module provided for another embodiment of the present invention;

[0066] Fig. 9 A schematic diagram of the structure of an up-conversion module provided for another embodiment of the present invention;

[0067] Fig.10 A schematic diagram of the structure of an intermediate frequency digital frequency storage module provided in other embodiments of the present invention. DETAILED DESCRIPTION

[0068] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention but not to limit the scope of the present invention.

[0069] like Figure 1 As shown, a target clutter simulation device provided by an embodiment of the present invention includes: a switch filter module 1101, a frequency conversion module 1102, an intermediate frequency digital frequency storage module 1103 and a control module 1104;

[0070] In a certain embodiment, the up-down frequency conversion module of the wide-band target clutter simulation device needs to be designed in frequency bands, and the frequency band divisions may include: 1-6 GHz, 6-10 GHz, 10-14 GHz, 14-18 GHz;

[0071] The switch filter module 1101, the frequency conversion module 1102 and the intermediate frequency digital frequency storage module 1103 are connected in sequence;

[0072] The control module 1104 is connected to the switch filter module 1101, the frequency conversion module 1102 and the intermediate frequency digital frequency storage module 1103 respectively;

[0073] The switch filtering module 1101 is used to receive a first radio frequency signal to be processed, and perform a first filtering process on the first radio frequency signal according to a first control parameter to obtain a first radio frequency signal;

[0074] The frequency conversion module 1102 is used to perform a first frequency conversion process on the first radio frequency signal according to the second control parameter to obtain an intermediate frequency signal;

[0075] The intermediate frequency digital frequency storage module 1103 is used to perform target signal analog processing on the intermediate frequency signal according to the third control parameter;

[0076] The frequency conversion module 1102 is further configured to perform a second frequency conversion process on the preset processed intermediate frequency signal according to a second control parameter to obtain a second radio frequency signal;

[0077] The switch filtering module 1101 is further configured to perform a second filtering process on the second RF signal according to the first control parameter to obtain a target signal;

[0078] It should be noted that, in a certain embodiment, the up and down frequency conversion link includes a switch filter module 1101 and a frequency conversion module 1102, the switch filter module 1101 includes a downlink switch filter and an uplink switch filter, and the frequency conversion module 1102 includes a down-conversion module and an up-conversion module. After receiving the RF signal, the downlink switch filter in the switch filter module 1101 limits, selects, and filters the signal, and then sends it to the down-conversion module of the frequency conversion module 1102 for down-conversion processing, and the processed intermediate frequency signal is sent to the intermediate frequency digital frequency storage module 1103. The intermediate frequency signal processed by the intermediate frequency digital frequency storage module 1103 is first converted into an RF signal through the up-conversion processing of the frequency conversion module 1102, and then sent to the uplink switch filter of the switch filter module 1101 for filtering, amplification, attenuation, and transmission.

[0079] Preferably, in a certain embodiment, the receiving down-conversion first performs receiving filtering, selects the radar detection signal of 1 to 18 GHz according to the frequency band division, and then sends it to the frequency conversion module 1102 at the back end; the frequency conversion module 1102 adopts a two-stage frequency conversion system, and converts the selected signal after receiving filtering into an intermediate frequency signal with a bandwidth of 1.2 GHz and a bandwidth of 1 GHz through an independently variable local oscillator signal and a fixed second local oscillator signal, and sends it to the intermediate frequency digital storage module 1103 for intermediate frequency signal processing. It should be noted that the function of filtering and selecting is to select the frequency band. The working frequency band design of the target clutter simulation device is relatively wide, and can be applied to all radar training within the range of 1 to 18 GHz.

[0080] The control module 1104 is used to calculate the first control parameter, the second control parameter and the third control parameter according to the received target simulation parameters, and send the first control parameter to the switch filter module 1101; send the second control parameter to the frequency conversion module 1102; send the third control parameter to the intermediate frequency digital storage module 1103. Among them, the target simulation parameters are input into the control software by the host computer through the network interface and determined by the user who needs the target clutter simulation device. It should be noted that the working parameters of each module are set according to the requirements to complete the simulation function of the target and clutter signals. The working frequency band required for radar training can be selected by sending the control parameters, which improves the applicable frequency band of the device.

[0081] It should be noted that, in a certain embodiment, the structure of the control module 1104 is as follows: Figure 4 As shown, the design method of the control module 1104 may include: after the target simulation parameters are received through the network interface, they need to be parsed into control parameters of the switch filter module 1101, the frequency conversion module 1102 and the intermediate frequency digital storage module 1103 through calculation and conversion, that is, the first control parameter, the second control parameter and the third control parameter, which are issued according to a certain timing relationship, and the parameters and monitoring data sent back by the switch filter module 1101, the frequency conversion module 1102 and the intermediate frequency digital storage module 1103 are received, and output to the display control module through the network interface for display. Among them, the data sent back by the target clutter simulation device include real-time parameters such as target signal frequency, current target distance, current speed, receiving attenuation, transmitting attenuation, monitoring data, etc. In the target signal simulation, the real-time parameters are sent back at a fixed period.

[0082] In another embodiment, the control software in the control module 1104 controls the process, such as Figure 5 As shown, firstly, the internal hardware is initialized, the network is initialized, self-checking is performed, interrupts are enabled, and timed interrupts are enabled. When an interrupt occurs, the target parameter is calculated. If no interrupt occurs, the interrupt is monitored continuously. After the target parameter calculation is completed, the radar parameter is measured, and then the target parameter is output. After the target parameter is output, the interrupt is monitored continuously to see if it occurs. In another embodiment, each software module is designed according to the program flow chart, and the target parameter can be calculated by the following first formula, second formula, and third formula;

[0083] The following is a first formula that expresses the relationship between the delay time τ and the radial distance R of the target:

[0084] τ=2R / c,

[0085] Among them, τ represents the delay time, R represents the radial distance of the target, and c represents the propagation speed of electromagnetic waves in the air.

[0086] According to the second formula:

[0087] P r =C(P t / R 4 ),

[0088] Obtain the distance attenuation characteristics of the target echo: the power of the target echo is inversely proportional to the fourth power of the distance R from the target to the radar;

[0089] Where C is a constant determined by radar and target parameters, P r Indicates the power of the target echo received by the radar, P t represents the power of the radar transmitting wave, and R represents the distance from the target to the radar.

[0090] When the target moves radially relative to the radar, the target echo will produce a Doppler frequency shift. According to the third formula:

[0091] f d =2v r / λ,

[0092] Calculate the Doppler frequency, where λ is the emission wavelength and v r Indicates the radial velocity of the target. The pulse width is measured by the time interval between two points at 50% of the amplitude on the rising and falling edges of the pulse. When the pulse envelope sequence arrives, the pulse data is classified by differential operation, and the rising edge, falling edge and top data (pulse peak value) are taken out and sent to the pulse width measurement module. The 50% top data is used as the starting point and end point of the pulse width calculation, and the pulse width is measured by the internal counter.

[0093] In one embodiment, the target clutter simulation device can be selected to work in a frequency band of 1 to 18 GHz, and the instantaneous working bandwidth can be 1 GHz. The up-down frequency conversion module of the wide-band target clutter simulation device needs to be designed in frequency bands, such as Figure 3 As shown, the idea of ​​selecting the frequency band division is: 1-6GHz, 6-10GHz, 10-14GHz, 14-18GHz. The processing method is: the receiving down-conversion first performs receiving filtering, selects the radar detection signal of 1-18GHz according to the frequency band division, and then sends it to the back-end frequency conversion module 1102; the frequency conversion module 1102 adopts a two-stage frequency conversion system, through an independently variable local oscillator signal and a fixed second local oscillator signal, the selected signal after receiving filtering is converted into an intermediate frequency signal with a bandwidth of 1.2GHz and a bandwidth of 1GHz, and sent to the intermediate frequency digital storage module 1103 for intermediate frequency signal processing.

[0094] The signal processed by the intermediate frequency digital frequency storage module 1103 is 1.2GHz and has a bandwidth of 1GHz. It is converted into a 1-6GHz, or 6-10GHz, or 10-14GHz, or 14-18GHz radio frequency signal through the up-conversion link of the frequency conversion module 1102, and sent to the transmitting switch filter component for bandpass filtering and gating, and then transmitted after amplification and attenuation. It should be noted that in a certain embodiment, the attenuation range of the programmable attenuation can be determined according to the range of fluctuation of the simulated target amplitude.

[0095] In another embodiment, the design of the intermediate frequency digital frequency storage module 1103 may include: determining the instantaneous working bandwidth of the intermediate frequency digital frequency storage module 1103 according to the instantaneous bandwidth of the target clutter simulation device; determining the storage depth of the DDR (double rate synchronous dynamic random access memory) selected by the digital frequency storage module according to the target simulation distance range and the size of the injected clutter data; determining the clock frequency of the digital frequency storage module according to the target distance simulation accuracy and the pulse width and pulse repetition period measurement errors; and determining the attenuation range of the receiving link attenuator and the number of bits of the AD in the intermediate frequency digital frequency storage module 1103 according to the requirements of the receiving instantaneous dynamic range. Determine the sampling rate of the selected DDS (direct digital frequency synthesis) chip according to the speed simulation accuracy and the Doppler simulation accuracy. It should be noted that in a certain embodiment, the speed simulation accuracy and the Doppler simulation accuracy can be determined according to the demand indicators.

[0096] The beneficial effects of the present invention are as follows: the present solution realizes wide-band target interference simulation and radar test measurement through a target clutter simulation device including a switch filter module 1101, a frequency conversion module 1102, an intermediate frequency digital frequency storage module 1103 and a control module 1104, and is more helpful for radar simulation training. The present solution solves the problem of single frequency band and repeated development of target clutter simulation equipment in traditional methods. The present solution has a high degree of generalization and standardization, solves the problem of repeated development of target clutter simulation equipment for radars in different frequency bands, and adds a radar parameter measurement function, with richer functions.

[0097] Preferably, in any of the above embodiments, the switch filter module 1101 includes: an uplink switch filter module and a downlink switch filter module;

[0098] The downlink switch filter module is used to receive a first radio frequency signal to be processed, and perform amplitude limiting and bandpass filtering of a preset frequency band on the first radio frequency signal according to a first control parameter to obtain the first radio frequency signal;

[0099] The uplink switch filtering module is used to filter, amplify and attenuate the second radio frequency signal according to the first control parameter to obtain a target signal.

[0100] This solution limits and filters the received signal through the downlink switch filter module, and can control the target clutter simulation device to work in the corresponding working frequency band. The RF signal is filtered, amplified, and attenuated through the uplink switch filter module.

[0101] Preferably, in any of the above embodiments, Figure 6 As shown, the downlink switch filter module includes: a limiter, a first switch, a first bandpass filter group and a second switch;

[0102] The limiter, the first switch, the first bandpass filter group and the second switch are connected in sequence;

[0103] The first bandpass filter group includes a plurality of bandpass filters of different frequency bands, and the bandpass filters of each frequency band are respectively connected to the first switch and the second switch. The plurality of bandpass filters of different frequency bands may include: a 1-6 GHz bandpass filter, a 6-10 GHz bandpass filter, a 10-14 GHz bandpass filter, and a 14-18 GHz bandpass filter.

[0104] It should be noted that the downlink switch filter module limits the received signal and performs bandpass filtering of the corresponding frequency band, which can control the target clutter simulation device to work in the corresponding working frequency band, and selects the signal of the frequency band and sends it to the frequency conversion module 1102 for down-conversion processing.

[0105] This solution limits and filters the received signal through the downlink switch filter module, and can control the target clutter simulation device to work in the corresponding working frequency band.

[0106] Preferably, in a certain embodiment, the signal processed by the intermediate frequency digital frequency storage module 1103 is 1.2GHz, and the bandwidth is 1GHz. It is converted into a 1-6GHz, or 6-10GHz, or 10-14GHz, or 14-18GHz radio frequency signal through the up-conversion link of the frequency conversion module 1102, and sent to the transmitting switch filter component for bandpass filtering and gating, and then transmitted after amplification and attenuation. The attenuation range of the program-controlled attenuation is determined according to the range of the simulated target amplitude fluctuation, that is, it is determined by the range of the simulated target amplitude fluctuation, and the size of the output signal is adjusted to simulate the strength of the target echo signal.

[0107] Preferably, in any of the above embodiments, Figure 7 As shown, the uplink switch filter module includes: a third switch, a second bandpass filter group, a fourth switch, an amplifier and a programmable attenuator;

[0108] The third switch, the second bandpass filter group, the fourth switch, the amplifier and the programmable attenuator are connected in sequence;

[0109] The programmable attenuator is connected to the third switch and the fourth switch respectively;

[0110] The second bandpass filter group includes a plurality of bandpass filters of different frequency bands, and the bandpass filters of each frequency band are respectively connected to the third switch and the fourth switch. The plurality of bandpass filters of different frequency bands may include: a 1-6 GHz bandpass filter, a 6-10 GHz bandpass filter, a 10-14 GHz bandpass filter, and a 14-18 GHz bandpass filter.

[0111] This solution filters, amplifies and attenuates the RF signal through the uplink switch filter module, and determines the attenuation range of the programmable attenuation according to the range of the simulated target amplitude fluctuation.

[0112] Preferably, in any of the above embodiments, the frequency conversion module 1102 includes: an up-conversion module and a down-conversion module; wherein the down-conversion module is as follows: Figure 8 As shown, it includes primary mixing, secondary mixing and frequency synthesis. The first RF signal is processed by primary mixing and then secondary mixing to output an intermediate frequency signal; it also includes inputting the signal into the primary mixing module after secondary mixing through two local oscillators and then through a local oscillator; the up-conversion module is as shown in FIG. Fig. 9 As shown, the input signal is mixed once and twice to output a second RF signal, wherein the secondary mixing result is input into the primary frequency synthesis module after passing through a local oscillator, a frequency synthesis module and a second local oscillator.

[0113] The down-conversion module is used to perform down-conversion processing on the first radio frequency signal according to the second control parameter to obtain an intermediate frequency signal;

[0114] The up-conversion module is used to perform up-conversion processing on the preset processed intermediate frequency signal according to the second control parameter to obtain a second radio frequency signal.

[0115] This solution uses a frequency conversion module to perform frequency conversion processing on the intermediate frequency signal and control the target clutter simulation equipment to operate in the corresponding working frequency band.

[0116] Preferably, in any of the above embodiments, the control module 1104 includes: control software and a display and control module; the control software is used to receive the target simulation parameters, calculate the first control parameter, the second control parameter and the third control parameter according to the target simulation parameters, and output them to the display and control module;

[0117] The display and control module is used to display the first control parameter, the second control parameter and the third control parameter.

[0118] In one embodiment, the data sent back by the target clutter simulation device includes real-time parameters such as target signal frequency, current target distance, current speed, receiving attenuation, transmitting attenuation, monitoring data, etc. In the target signal simulation, the real-time parameters are sent back at a fixed period.

[0119] This solution realizes the calculation and parameter measurement functions of the target simulation parameters through the control module 1104; and realizes the display of the feedback parameters and monitoring data through the display control module.

[0120] Preferably, in one embodiment, Fig.10 As shown, the schematic diagram of the structure of the intermediate frequency digital frequency storage module 1103 is shown. After the intermediate frequency signal passes through ADC, broadband direct digital control, frequency measurement and spectrum analysis, it passes through digital frequency storage processing, and then passes through digital up-conversion and DAC processing to output the intermediate frequency signal. The design method of the intermediate frequency digital frequency storage module 1103 may include:

[0121] The digital frequency storage module needs to complete three functions: target simulation, clutter simulation and radar parameter measurement. It simulates the distance information of the target echo by delay, simulates the speed information of the target echo by adding the Doppler frequency, and simulates the amplitude information of the target echo by the intensity change of the signal; simulates different clutter environments through the software preset clutter model or injected clutter data; and measures the amplitude, pulse width and other parameters of the received signal through the software algorithm;

[0122] Determine the instantaneous working bandwidth of the intermediate frequency digital frequency storage module 1103 according to the instantaneous bandwidth of the target clutter simulation device;

[0123] Determine the storage depth of DDR selected by the digital frequency storage module according to the target simulation maximum delay τmax and the size of the injected clutter data;

[0124] DDR storage depth = number of AD bits of digital frequency storage module * sampling rate of digital frequency storage module * τmax,

[0125] The counting clock frequency of the digital frequency storage module determines the target distance simulation accuracy. Target distance simulation accuracy = c / (2*f), c is the speed of light, and f is the counting clock frequency of the digital frequency storage module.

[0126] The receiving instantaneous dynamic range determines the effective number of bits of AD in the intermediate frequency digital frequency storage module 1103;

[0127] in,

[0128] Receiving instantaneous dynamic range = 20*log(2^AD effective number of bits / 1).

[0129] When there is no directly selectable hardware product for calculating the effective number of bits of AD, a higher effective number of bits of AD should be selected to meet the requirements of the instantaneous dynamic range of reception.

[0130] Determine the sampling rate of the selected DDS based on the velocity simulation accuracy and Doppler accuracy;

[0131] Since DDS is usually implemented using an NCO (numerically controlled oscillator), n is the number of bits of the NCO, so:

[0132] Doppler frequency accuracy = sampling frequency of digital frequency storage module / 2^n.

[0133] It should be noted that the selection of the hardware of the intermediate frequency digital frequency storage module 1103 can be determined by confirming the parameters of the instantaneous working bandwidth, the clock frequency, the number of bits of the AD and the sampling rate of the DDS.

[0134] In one embodiment, if Figure 2 As shown, a target clutter simulation method includes:

[0135] receiving a first radio frequency signal to be processed, and performing a first filtering process on the first radio frequency signal according to a first control parameter to obtain a first radio frequency signal;

[0136] Performing a first frequency conversion process on the first radio frequency signal according to the second control parameter to obtain an intermediate frequency signal;

[0137] Performing target signal simulation processing on the intermediate frequency signal according to the third control parameter;

[0138] Performing a second frequency conversion process on the preset processed intermediate frequency signal according to a second control parameter to obtain a second radio frequency signal;

[0139] Performing a second filtering process on the second radio frequency signal according to the first control parameter to obtain a target signal;

[0140] Before the first filtering process, the first control parameter, the second control parameter and the third control parameter are calculated according to the received target analog parameter, and the first control parameter is sent to the switch filtering module 1101; the second control parameter is sent to the frequency conversion module 1102; and the third control parameter is sent to the intermediate frequency digital storage module 1103.

[0141] This solution implements wide-band target interference simulation by executing the target clutter simulation method in the target clutter simulation device, and can also realize radar test measurement, which is more helpful for radar simulation training. This solution solves the problem of single frequency band and repeated development of target clutter simulation equipment in traditional methods. This solution has a high degree of universality and standardization, solves the problem of repeated development of target clutter simulation equipment for radars in different frequency bands, and adds radar parameter measurement function, with richer functions.

[0142] Preferably, in any of the above embodiments, receiving a first radio frequency signal to be processed, performing a first filtering process on the first radio frequency signal according to a first control parameter, and obtaining the first radio frequency signal specifically includes:

[0143] According to the first control parameter, the first radio frequency signal is subjected to amplitude limiting and band-pass filtering of a preset frequency band to obtain the first radio frequency signal;

[0144] Performing a second filtering process on the second radio frequency signal according to the first control parameter to obtain the target signal specifically includes: performing filtering, amplification and attenuation processing on the second radio frequency signal according to the first control parameter to obtain the target signal.

[0145] This solution limits and filters the received signal through the downlink switch filter module, and can control the target clutter simulation device to work in the corresponding working frequency band. The RF signal is filtered, amplified, and attenuated through the uplink switch filter module.

[0146] Preferably, in any of the above embodiments, performing a first frequency conversion process on the first radio frequency signal according to the second control parameter to obtain an intermediate frequency signal specifically includes:

[0147] Down-converting the first radio frequency signal according to the second control parameter to obtain an intermediate frequency signal;

[0148] Performing a second frequency conversion process on the preset processed intermediate frequency signal according to the second control parameter to obtain the second radio frequency signal specifically includes:

[0149] The preset processed intermediate frequency signal is up-converted according to the second control parameter to obtain a second radio frequency signal.

[0150] This solution implements frequency conversion processing on the intermediate frequency signal through the frequency conversion module 1102, and controls the target clutter simulation device to work in the corresponding working frequency band.

[0151] Preferably, in any of the above embodiments, it further comprises: receiving a target simulation parameter, calculating a first control parameter, a second control parameter and a third control parameter according to the target simulation parameter, and outputting the first control parameter, the second control parameter and the third control parameter to the display and control module;

[0152] The first control parameter, the second control parameter and the third control parameter are displayed.

[0153] This solution realizes the calculation and parameter measurement functions of the target simulation parameters through the control module 1104; and realizes the display of the feedback parameters and monitoring data through the display control module.

[0154] A radar testing device comprises: a target clutter simulation device using any one of the above embodiments.

[0155] This solution realizes wide-band target interference simulation and radar test measurement through a target clutter simulation device including a switch filter module 1101, a frequency conversion module 1102, an intermediate frequency digital frequency storage module 1103 and a control module 1104, which is more helpful for radar simulation training. This solution solves the problem of single frequency band and repeated development of target clutter simulation equipment in traditional methods. This solution has a high degree of generalization and standardization, solves the problem of repeated development of target clutter simulation equipment for radars in different frequency bands, and adds radar parameter measurement function, with richer functions.

[0156] It can be understood that in some embodiments, some or all of the optional implementation modes in the above embodiments may be included.

[0157] It should be noted that the above embodiments are method embodiments corresponding to the previous product embodiments. For the description of the optional implementation methods in the method embodiments, reference can be made to the corresponding description in the above product embodiments, which will not be repeated here.

[0158] The reader should understand that in the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0159] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0160] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of the present invention.

[0161] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0162] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0163] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A target clutter simulation device, characterized in that: include: Switch filter module, frequency conversion module, intermediate frequency digital frequency storage module and control module; The switch filter module, the frequency conversion module and the intermediate frequency digital frequency storage module are connected in sequence; The control module is respectively connected to the switch filter module, the frequency conversion module and the intermediate frequency digital frequency storage module; The switch filter module is used to receive a first radio frequency signal to be processed, and perform a first filtering process on the first radio frequency signal according to a first control parameter sent by the control module to obtain a first radio frequency signal; The frequency conversion module is used to perform a first frequency conversion process on the first radio frequency signal according to the second control parameter sent by the control module to obtain an intermediate frequency signal; The intermediate frequency digital frequency storage module is used to perform target signal simulation processing on the intermediate frequency signal according to the third control parameter issued by the control module; The frequency conversion module is further used to perform a second frequency conversion process on the preset processed intermediate frequency signal according to the second control parameter to obtain a second radio frequency signal; The switch filtering module is further used to perform a second filtering process on the second radio frequency signal according to the first control parameter to obtain a target signal; The frequency conversion module includes: an up-conversion module and a down-conversion module; The down-conversion module is used to perform down-conversion processing on the first radio frequency signal according to the second control parameter to obtain an intermediate frequency signal; The up-conversion module is used to perform up-conversion processing on the preset processed intermediate frequency signal according to the second control parameter to obtain a second radio frequency signal; The control software control flow in the control module is as follows: First, perform internal hardware initialization, network initialization, self-check, enable interrupts, and enable timed interrupts. When an interrupt occurs, calculate the target parameters. If no interrupt occurs, continue to monitor the interrupt. After the target parameter calculation is completed, measure the radar parameters, and then output the target parameters. After the target parameters are output, continue to monitor whether the interrupt occurs. Design each software module according to the program flow chart. The target parameters are calculated using the first, second, and third formulas below. The first formula expresses the relationship between the delay time τ and the radial distance R of the target: τ=2R / c Among them, τ represents the delay time, R represents the radial distance of the target, and c represents the propagation speed of electromagnetic waves in the air; According to the second formula: P r =C(P t / R 4 ), Obtain the distance attenuation characteristics of the target echo: the power of the target echo is inversely proportional to the fourth power of the distance R from the target to the radar; Where C is a constant determined by radar and target parameters, P r Indicates the power of the target echo received by the radar, P t represents the power of the radar transmitting wave, and R represents the distance from the target to the radar; When the target moves radially relative to the radar, the target echo will produce a Doppler frequency shift. According to the third formula: in d =2v r / λ, Calculate the Doppler frequency, where λ is the emission wavelength and v r Indicates the radial velocity of the target; the measurement of pulse width is determined by the time interval between two points at 50% amplitude on the rising and falling edges of the pulse; when the pulse envelope sequence arrives, the pulse data is classified by differential operation, the rising edge, falling edge and pulse peak are taken out and sent to the pulse width measurement module, and the 50% top data is used as the starting point and end point of the pulse width calculation, and the pulse width is measured through the internal counter; After the intermediate frequency signal passes through ADC, broadband direct digital control, frequency measurement and spectrum analysis, it undergoes digital frequency storage processing, and then undergoes digital up-conversion and DAC processing to output the intermediate frequency signal. The design method of the intermediate frequency digital frequency storage module includes: The digital frequency storage module completes three functions: target simulation, clutter simulation and radar parameter measurement. It simulates the distance information of the target echo by delay, simulates the speed information of the target echo by adding the Doppler frequency, and simulates the amplitude information of the target echo by the intensity change of the signal. It simulates different clutter environments through the clutter model preset by the software or the injected clutter data. It measures the amplitude, pulse width and other parameters of the received signal through the software algorithm. Determine the instantaneous working bandwidth of the intermediate frequency digital frequency storage module according to the instantaneous bandwidth of the target clutter simulation device; Determine the storage depth of DDR selected by the digital frequency storage module according to the target simulation maximum delay τmax and the size of the injected clutter data; DDR storage depth = number of AD bits of digital frequency storage module * sampling rate of digital frequency storage module * τmax, The counting clock frequency of the digital frequency storage module determines the target distance simulation accuracy. The target distance simulation accuracy = c / (2*f), where c is the speed of light and f is the counting clock frequency of the digital frequency storage module. The receiving instantaneous dynamic range determines the effective number of bits of AD in the intermediate frequency digital frequency storage module; in, Receive instantaneous dynamic range = 20*log(2^AD effective number of bits / 1); Determine the sampling rate of the selected DDS based on the velocity simulation accuracy and Doppler accuracy; Since DDS is usually implemented using a digitally controlled oscillator, n is the number of bits of the NCO, so: Doppler frequency accuracy = sampling frequency of the digital frequency storage module / 2^n; After confirming the parameters of instantaneous working bandwidth, clock frequency, number of bits of AD and sampling rate of DDS, the selection of hardware for intermediate frequency digital frequency storage module is determined.

2. A target clutter simulation device according to claim 1, characterized in that: The switch filter module includes: an uplink switch filter module and a downlink switch filter module; The downlink switch filtering module is used to receive a first radio frequency signal to be processed, and perform amplitude limiting and bandpass filtering of a preset frequency band on the first radio frequency signal according to a first control parameter to obtain a first radio frequency signal; The uplink switch filtering module is used to filter, amplify and attenuate the second radio frequency signal according to the first control parameter to obtain a target signal.

3. A target clutter simulation device according to claim 2, characterized in that: The downlink switch filter module includes: a limiter, a first switch, a first bandpass filter group and a second switch; The limiter, the first switch, the first bandpass filter group and the second switch are connected in sequence; The first bandpass filter group includes a plurality of bandpass filters of different frequency bands, and the bandpass filter of each frequency band is connected to the first switch and the second switch respectively.

4. A target clutter simulation device according to claim 2, characterized in that: The uplink switch filter module includes: a third switch, a second bandpass filter group, a fourth switch, an amplifier and a programmable attenuator; The third switch, the second bandpass filter group, the fourth switch, the amplifier and the programmable attenuator are connected in sequence; The programmable attenuator is connected to the third switch and the fourth switch respectively; The second band-pass filter group includes a plurality of band-pass filters of different frequency bands, and the band-pass filter of each frequency band is connected to the third switch and the fourth switch respectively.

5. A target clutter simulation device according to claim 1, characterized in that: The control module includes: control software and display control module; The control software is used to receive the target simulation parameters, calculate the first control parameter, the second control parameter and the third control parameter according to the target simulation parameters, and output them to the display and control module; The display and control module is used to display the first control parameter, the second control parameter and the third control parameter.

6. A target clutter simulation method, characterized in that: A target clutter simulation device according to any one of claims 1 to 5 comprises: receiving a first radio frequency signal to be processed, and performing a first filtering process on the first radio frequency signal according to a first control parameter sent by a control module to obtain a first radio frequency signal; Performing a first frequency conversion process on the first radio frequency signal according to a second control parameter sent by the control module to obtain an intermediate frequency signal; Performing target signal simulation processing on the intermediate frequency signal according to the third control parameter issued by the control module; Performing a second frequency conversion process on the preset processed intermediate frequency signal according to the second control parameter to obtain a second radio frequency signal; Perform a second filtering process on the second radio frequency signal according to the first control parameter to obtain a target signal.

7. A target clutter simulation method according to claim 6, characterized in that: The receiving a first radio frequency signal to be processed and performing a first filtering process on the first radio frequency signal according to a first control parameter to obtain the first radio frequency signal specifically includes: The first radio frequency signal is subjected to amplitude limiting and band-pass filtering of a preset frequency band according to the first control parameter to obtain a first radio frequency signal.

8. A target clutter simulation method according to claim 6, characterized in that: The performing a second filtering process on the second radio frequency signal according to the first control parameter to obtain the target signal specifically includes: performing filtering, amplifying and attenuating processes on the second radio frequency signal according to the first control parameter to obtain the target signal.

9. A radar testing device, characterized in that: include: A target clutter simulation device according to any one of claims 1 to 5 is used.

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