Real-time radar echo signal simulation method and device based on digital storage

Abstract

The invention discloses a real-time radar echo signal simulation method and device based on digital storage, and the method comprises the steps: building digital demonstration scene information according to the scene information obtained by an external scene input module; collecting, processing and storing a real object radar wireless signal to obtain wireless signal information; according to the digital demonstration scene information, a parallel computing method is adopted, an echo parameter module is used for processing the wireless signals, and echo signal parameter information is obtained; and performing time synchronization on the FPGA module, the physical radar and the digital demonstration scene, and processing the echo signal parameter information by using the signal processing module to obtain a simulated radar echo signal. High-speed real-time simulation of echo signals is improved by efficient parallel calculation of parameters such as multiple radars, multiple targets and multiple paths; the parallel computing software modeling and FPGA combined simulation method is adopted, and the method has the advantages of being higher in efficiency, more flexible, more accurate in calculation and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of signal processing, and in particular to a method and device for simulating real-time radar echo signals based on digital storage. Background Art

[0002] Modern radar systems are increasingly used in both military and civilian applications, and their functionality is becoming increasingly complex. For example, in the military, multi-radar coordinated combat systems enable comprehensive monitoring and precision strikes in complex battlefield environments. In the civilian sector, multi-radar systems are used for air traffic control and weather monitoring. These applications require radar systems to simultaneously process multiple targets and dynamically track and identify them.

[0003] Radar echo signal simulation is used to model and simulate the spatial propagation effects of radar RF signals, assisting in radar function and performance testing. With the rapid development and advancement of the electronic information field, various types of radars and other electronic equipment are constantly emerging, and the electromagnetic environment has become increasingly complex, posing greater challenges to wireless signal simulation. In order to adapt to complex electromagnetic environments, radar echo signal simulation needs to be able to simulate scenarios where multiple radars are working simultaneously, model the position and speed of moving platforms such as radars, targets, and interference sources, simulate target signal reflection characteristics such as radar scattering cross-sections, model target echo signals using RF signal propagation theoretical models, model echo signals from various backgrounds, obtain target echo signal amplitude, Doppler, and phase parameters to form signal parameter data, and transmit them to the signal generation device to achieve signal waveform output.

[0004] Traditional radar echo simulation methods mainly focus on simulating a single radar for a single target and are unable to meet the requirements of complex scenarios with multiple radars and multiple targets. Furthermore, they are significantly inadequate when simulating dynamic scenarios. The dynamic characteristics of radar targets (such as motion trajectory, velocity changes, etc.) are important aspects of radar system performance evaluation, but existing simulation methods can often only simulate static or simply moving targets and cannot truly reflect the characteristics of radar targets in complex dynamic environments. Furthermore, dynamic simulation of multiple radars and multiple targets requires a high degree of real-time performance to ensure that the simulation results can truly reflect the actual working state of the radar system. However, existing methods often suffer from insufficient real-time performance when dealing with complex scenarios and cannot meet the needs of practical applications. Summary of the Invention

[0005] The main purpose of the present invention is to solve the shortcomings of existing simulation methods in dynamic scene simulation and real-time performance, and to achieve accurate simulation of multi-radar multi-target dynamic scenes.

[0006] To achieve the above-mentioned object, the first aspect of the embodiment of the present invention discloses a method for simulating real-time radar echo signals based on digital storage, the method comprising:

[0007] S1. Establishing digital demonstration scene information based on scene information obtained by an external scene input module; the digital demonstration scene information includes information of a plurality of independent path points; the digital demonstration scene information defines the overall scene position and velocity according to a unified coordinate representation method, and the scene coordinates are defined as ECEF;

[0008] S2. Using the signal processing module, obtain wireless signals from the physical radar, process and store them, and obtain wireless signal information;

[0009] S3. Processing the wireless signal using an echo parameter processing module using a parallel computing method according to the digital demonstration scene information to obtain echo signal parameter information; the echo signal parameters include echo signal amplitude, Doppler frequency, and round-trip delay;

[0010] S4. Time-synchronize the FPGA module, the physical radar, and the digital demonstration scene, and use the D / A unit in the signal processing module to process the echo signal parameter information to obtain a simulated radar echo signal.

[0011] As an optional implementation manner, in the first aspect of the embodiment of the present invention, the using of the signal processing module to obtain wireless signals from the physical radar, and processing and storing the obtained wireless signal information includes:

[0012] S21. Collect and store radio frequency signals emitted by the physical radar device;

[0013] S22, using the A / D unit in the signal processing module to sample the collected radio frequency signal to obtain a discrete signal;

[0014] Assuming that the total sampling time of the continuous signal is T and the discrete time length is L, the corresponding discrete signal Expressed as:

[0015] s[n]=s I [n]+js Q [n],n=0,1,…,L-1;

[0016] Among them, s I [n]、s Q [n] are the in-phase and quadrature components of the discrete signal respectively;

[0017] S23. Analyze the discrete signal to obtain a discrete signal sequence; the discrete signal sequence includes a real-valued IQ sequence and an amplitude and phase AP sequence;

[0018] The real-valued IQ sequence is:

[0019]

[0020] in,

[0021] The amplitude and phase AP sequence is:

[0022]

[0023] in, The amplitude and phase of the i-th element are:

[0024]

[0025] S24. Detect and process the discrete signal sequence to obtain wireless signal information, and store it in the internal storage space of the FPGA unit.

[0026] As an optional implementation manner, in the first aspect of the embodiment of the present invention, the detecting and processing of the discrete signal sequence to obtain wireless signal information and storing it in the internal storage space of the FPGA unit includes:

[0027] S241, processing the discrete signal sequence to obtain a pulse period;

[0028] S242. Obtain wireless signal information through threshold comparison according to the threshold detection model;

[0029] The single pulse period signal is:

[0030]

[0031] Where thi is the set detection threshold; T p is the pulse period;

[0032] The pulse period T p , according to the radar pulse period, establish the minimum simulation time segment. If there are multiple radars, define the simulation segment according to the greatest common divisor of the radar period.

[0033] S243. Input the wireless signal information into the internal storage space of the FPGA unit for storage.

[0034] It should be noted that, in this embodiment, the wireless signal is stored in the internal storage space of the FPGA unit. When performing multi-radar multi-target simulation, the wireless signal can be directly called from the storage space and processed in parallel with the echo parameter calculation, which speeds up the processing speed and improves work efficiency.

[0035] As an optional implementation manner, in the first aspect of the embodiment of the present invention, the method of processing the wireless signal using an echo parameter processing module according to the digital demonstration scene information using a parallel computing method to obtain echo signal parameter information includes:

[0036] S31, processing the independent path point parameter information through high-order modeling according to the digital demonstration scene information to obtain dynamic parameter information;

[0037] S32. Calculate and process the wireless signal information according to the dynamic parameter information to obtain echo signal parameter information.

[0038] As an optional implementation, in the first aspect of the embodiment of the present invention, the independent path point parameter information is processed by high-order modeling according to the digital demonstration scene information to obtain dynamic parameter information, including:

[0039] S311, performing time difference processing on the simulation time of the digital demonstration scene information and the acquisition time of the wireless signal information to obtain a time difference value and a time difference coefficient;

[0040] The time difference value is expressed as:

[0041] remaining=t-time_vec[integer];

[0042] The time difference coefficient is expressed as:

[0043] Ratio=remaind / ((time_vec[integer+1]-time_vec[integer]));

[0044] Where t represents the current time of the platform being sought, integer represents the number of the independent path point interval at the current time, time_vec[i] represents the time information of the independent path point i, and time_vec[] stores the time information of the independent path point;

[0045] S312. Process the independent path point parameter information according to the time difference value and the time difference coefficient to obtain target dynamic parameter information, where the target dynamic parameter information includes target position, target speed, target azimuth, target pitch angle, and target roll angle;

[0046] The target location is:

[0047] x=(waypoints[integer+1].x-waypoints[ineger].x)*Ratio+waypoints[integer].x

[0048] y=(waypoints[integer+1].y-waypoints[ineger].y)*Ratio+waypoints[integer].y

[0049] z=(waypoints[integer+1].z-waypoints[ineger].z)*Ratio+waypoints[integer].z

[0050] Where x represents the current position of the target on the X axis, y represents the current position of the target on the Y axis, z represents the current position of the target on the Z axis, waypoints[i] represents the status information of the independent waypoint i, and waypoints[] stores the status information of all waypoints.

[0051] The target speed is:

[0052]

[0053] in,

[0054]

[0055] ν x Indicates the target's current speed on the X-axis, ν y Indicates the target's current velocity on the Y axis, ν z Indicates the target's current speed on the Z axis;

[0056] The target azimuth is:

[0057] yaw=(waypoints[integer+1].yaw-waypoints[integer].yaw)*Ratio

[0058] +waypoints[integer].yaw

[0059] Where yaw represents the azimuth of the target motion at the current moment, and waypoints[i].yaw represents the azimuth of the independent path point i;

[0060] The target pitch angle is:

[0061] pitch=(waypoints[integer+1].pitch-waypoints[integer].pitch)*Ratio

[0062] +waypoints[integer].pitch

[0063] Where pitch represents the pitch angle of the target motion at the current moment, and waypoints[i].pitch represents the pitch angle of the independent path point i;

[0064] The target roll angle is:

[0065] roll=(waypoints[integer+1].roll-waypoints[integer].roll)*Ratio

[0066] +waypoints[integer].roll

[0067] Where roll represents the roll angle of the target motion at the current moment, and waypoints[i].roll represents the roll angle of the independent path point i;

[0068] S313 , adopting a parallel processing method, using multiple threads to synchronously execute S311 to S312 to complete the dynamic parameter information of the execution time of all independent path points.

[0069] As an optional implementation manner, in the first aspect of the embodiment of the present invention, the calculating and processing the wireless signal information according to the dynamic parameter information to obtain the echo signal parameter information includes:

[0070] S321, obtaining an interpolation time point;

[0071] S322: Determine whether the radar and the target are visible based on the dynamic parameter information and the interpolation time point, and obtain a first determination result;

[0072] If the first judgment result is no, executing step S321;

[0073] If the first judgment result is yes, execute step S323;

[0074] S323, calculating and processing the input environmental parameter information to obtain a path attenuation parameter;

[0075] S324. Process the input target information to obtain radar cross sections of all targets;

[0076] S325: Calculate and process the wireless signal information according to the radar scattering cross section of the target and the path attenuation parameter to obtain echo signal parameter information.

[0077] As an optional implementation manner, in the first aspect of the embodiment of the present invention, processing the input target information to obtain radar cross sections of all targets includes:

[0078] S3241. Determine whether there is an external input target radar cross section file, and obtain a second determination result;

[0079] If the second judgment result is yes, execute step S3242;

[0080] If the second judgment result is no, executing step S3243;

[0081] S3242. Obtaining the radar cross section of the target according to an external input target radar cross section file;

[0082] S3243. Calculate the radar cross section of the target using a preset radar cross section calculation model. Preferably, the preset radar cross section calculation model may adopt a SwerlingX model.

[0083] As an optional implementation manner, in the first aspect of the embodiment of the present invention, the calculating and processing the wireless signal information based on the radar scattering cross section of the target and the path attenuation parameter to obtain the echo signal parameter information includes:

[0084] S3251. Select any signal from the wireless signal information as a transmission signal of radar i; select any target p from the input target information;

[0085] S3252: Process the transmitted signal of the radar i according to the radar cross section of the target and the path attenuation parameter to obtain echo signal parameters;

[0086] The echo signal is expressed as:

[0087]

[0088] Where S i,echo,p (t) represents the echo signal of the target i; A i,echo,p Indicates the echo signal amplitude; S i,t (t) represents the transmitted signal of radar i; t i,echo,p represents the round-trip delay between target p and radar i; f d,i,p represents the Doppler frequency between radar i and target p;

[0089] Echo signal amplitude A i,echo,p The calculation model is:

[0090]

[0091] Where, P t represents the transmitting power of radar i; G t represents the transmitting antenna gain of radar i; G r represents the receiving antenna gain of radar i; λ i represents the wavelength of the signal sent by radar i; σ p represents the radar cross section of target p; L s represents the path attenuation parameter between radar i and target p; R i,p It represents the distance between radar i and target p when the radar i signal reaches target p. The calculation method is:

[0092] R i,p =R 0,i,p -v i,p t;

[0093] Where R 0,i,p represents the distance between target p and radar i when radar i transmits the signal; v i,p represents the target velocity between target p and radar i;

[0094] The Doppler frequency f between radar i and target p d,i,p The calculation model is:

[0095]

[0096] The round-trip delay t between target p and radar i i,echo,p The calculation model is:

[0097]

[0098] Where c represents the speed of light;

[0099] S3253, looping through steps S451 to S452 to complete the echo signal parameters between all radars and targets, and obtaining echo signal parameter information.

[0100] As an optional implementation, in the first aspect of the embodiment of the present invention, the FPGA module, the physical radar, and the digital demonstration scene are time synchronized, and the echo signal parameter information is processed using the D / A unit in the signal processing module to obtain a simulated radar echo signal, including:

[0101] S41, time-synchronizing the FPGA module, the physical radar, and the digital demonstration scene;

[0102] It should be noted that this solution uses parallel processing and each module is executed synchronously. In order to improve operating efficiency, the FPGA module, physical radar and digital demonstration scene need to be synchronized with high precision.

[0103] S42. Acquire any set of echo signal parameters from the echo signal parameter information;

[0104] S43. Use FPGA to modulate any one group of echo signal parameters to obtain a modulated signal; the modulated signal is expressed as:

[0105]

[0106] S44, looping through steps S42 to S43 to obtain a multi-channel modulated signal set;

[0107] S45. Combine the multi-channel modulated signal set to obtain a simulated radar echo signal. Specifically, a multi-channel signal combination processing model is expressed as:

[0108]

[0109] Where S i,echo (t) represents the radar i echo signal; S i,echo,p (t) represents the echo signal of target p to radar i; P represents the number of targets.

[0110] A second aspect of an embodiment of the present invention discloses a real-time radar echo signal simulation device based on digital storage, which is used to implement a real-time radar echo signal simulation method based on digital storage as disclosed in the first aspect of the embodiment of the present invention. The device includes:

[0111] External scene input module; used to receive scene information input by the user, and use the input scene information to establish digital demonstration scene information, and input the digital demonstration scene information into the echo parameter calculation module;

[0112] Signal processing module; using FPGA unit, A / D unit and D / A unit to perform signal processing and storage to generate analog echo signal; the FPGA unit includes a processor and memory for signal calculation, processing and storage; the A / D unit is used to convert the wireless signal from analog signal to digital signal; the D / A unit is used to convert the wireless signal from digital signal to analog signal;

[0113] Echo parameter processing module; used to calculate echo signal parameter information based on digital demonstration scene information and wireless signals;

[0114] Physical radar module; the physical radar module represents a radar that exists in a physical sense and is used to transmit radar wireless signals and receive echo signals.

[0115] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0116] The present invention discloses a real-time radar echo signal simulation method and device based on digital storage. Based on the real-time acquisition, storage, and signal processing resources of an FPGA, this invention acquires radar output RF signals in real time, maps changes in software modeling calculation parameters to the generated radar echo signal in real time, and directly simulates the radar echo signal using the FPGA, fully leveraging the flexibility of radar simulation technology. This application provides a solution for relative changes in signal parameters such as amplitude, frequency, and delay caused by signal propagation, reflection attenuation from multiple targets, and dynamic changes between the target and the radar. Compared to current software simulation technology, the use of an FPGA to increase spatial physical signal output provides higher radar echo signal characteristics. Compared to simple hardware simulation sources, the combined simulation method of software modeling and FPGA offers greater flexibility and more accurate calculation accuracy. This invention proposes a complete architecture and method for radar echo simulation and signal parameter modulation, suitable for tasks such as radar signal modeling, propagation modeling, and radar testing in complex scenarios. In this architecture, parallel computing and multithreading are used to further improve efficiency and enhance simulation fidelity. BRIEF DESCRIPTION OF THE DRAWINGS

[0117] Figure 1 A flowchart of a real-time radar echo signal simulation method based on digital storage disclosed in an embodiment of the present invention;

[0118] Figure 2 A schematic diagram of parallel calculation for signal parameter processing disclosed in an embodiment of the present invention;

[0119] Figure 3 This is a schematic structural diagram of a real-time radar echo signal simulation device based on digital storage disclosed in an embodiment of the present invention;

[0120] Figure 4 This is a schematic diagram of the FPGA module structure disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0121] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0122] Example 1

[0123] See also Figure 1 . Figure 1 This is a flow chart of a real-time radar echo signal simulation method based on digital storage disclosed in an embodiment of the present invention.

[0124] like Figure 1 As shown, the embodiment of the present invention discloses a real-time radar echo signal simulation method based on digital storage, the method comprising:

[0125] S1. Establishing digital demonstration scene information based on scene information obtained by an external scene input module; the digital demonstration scene information includes information of a plurality of independent path points; the digital demonstration scene information defines the overall scene position and velocity according to a unified coordinate representation method, and the scene coordinates are defined as ECEF;

[0126] S2. Using a signal processing module, acquiring a wireless signal from a physical radar, processing and storing the signal to obtain wireless signal information; the physical radar represents a radar that exists in a physical sense;

[0127] S3. Processing the wireless signal using an echo parameter processing module using a parallel computing method according to the digital demonstration scene information to obtain echo signal parameter information; the echo signal parameters include echo signal amplitude, Doppler frequency, and round-trip delay;

[0128] S4. Time-synchronize the FPGA module, the physical radar, and the digital demonstration scene, and use the D / A unit in the signal processing module to process the echo signal parameter information to obtain a simulated radar echo signal.

[0129] In another optional embodiment, the method of using a signal processing module to obtain wireless signals from a physical radar, and processing and storing the wireless signal information includes:

[0130] S21. Collect and store radio frequency signals emitted by the physical radar device;

[0131] S22, using the A / D unit in the signal processing module to sample the collected radio frequency signal to obtain a discrete signal;

[0132] Assuming that the total sampling time of the continuous signal is T and the discrete time length is L, the corresponding discrete signal Expressed as:

[0133] s[n]=s I [n]+js Q [n],n=0,1,…,L-1;

[0134] Among them, s I [n]、s Q [n] are the in-phase and quadrature components of the discrete signal respectively;

[0135] S23. Analyze the discrete signal to obtain a discrete signal sequence; the discrete signal sequence includes a real-valued IQ sequence and an amplitude and phase AP sequence;

[0136] The real-valued IQ sequence is:

[0137]

[0138] in,

[0139] The amplitude and phase AP sequence is:

[0140]

[0141] in, The amplitude and phase of the i-th element are:

[0142]

[0143] S24. Detect and process the discrete signal sequence to obtain wireless signal information, and store it in the internal storage space of the FPGA unit.

[0144] In yet another optional embodiment, detecting and processing the discrete signal sequence to obtain wireless signal information and storing the information in an internal storage space of the FPGA unit includes:

[0145] S241, processing the discrete signal sequence to obtain a pulse period;

[0146] S242. Obtain wireless signal information through threshold comparison according to the threshold detection model;

[0147] The single pulse period signal is:

[0148]

[0149] Where thi is the set detection threshold; T p is the pulse period;

[0150] The pulse period T p , according to the radar pulse period, establish the minimum simulation time segment. If there are multiple radars, define the simulation segment according to the greatest common divisor of the radar period.

[0151] S243. Input the wireless signal information into the internal storage space of the FPGA unit for storage.

[0152] It should be noted that, in this embodiment, the wireless signal is stored in the internal storage space of the FPGA unit. When performing multi-radar multi-target simulation, the wireless signal can be directly called from the storage space and processed in parallel with the echo parameter calculation, which speeds up the processing speed and improves work efficiency.

[0153] In another optional embodiment, the method of processing the wireless signal using an echo parameter processing module according to the digital demonstration scene information using a parallel computing method to obtain echo signal parameter information includes:

[0154] S31, processing the independent path point parameter information through high-order modeling according to the digital demonstration scene information to obtain dynamic parameter information;

[0155] S32. Calculate and process the wireless signal information according to the dynamic parameter information to obtain echo signal parameter information.

[0156] In another optional embodiment, the independent path point parameter information is processed by high-order modeling based on the digital demonstration scene information to obtain dynamic parameter information, including:

[0157] S311, performing time difference processing on the simulation time in the digital demonstration scene information and the acquisition time of the wireless signal information to obtain a time difference value and a time difference coefficient;

[0158] The time difference value is expressed as:

[0159] remaining=t-time_vec[integer];

[0160] The time difference coefficient is expressed as:

[0161] Ratio=remaind / ((time_vec[integer+1]-time_vec[integer]));

[0162] Where t represents the current time of the platform being sought, integer represents the number of the independent path point interval at the current time, time_vec[i] represents the time information of the independent path point i, and time_vec[] stores the time information of the independent path point;

[0163] S312. Process the independent path point parameter information according to the time difference value and the time difference coefficient to obtain target dynamic parameter information, where the target dynamic parameter information includes target position, target speed, target azimuth, target pitch angle, and target roll angle;

[0164] The target location is:

[0165] x=(waypoints[integer+1].x-waypoints[ineger].x)*Ratio+waypoints[integer].x

[0166] y=(waypoints[integer+1].y-waypoints[ineger].y)*Ratio+waypoints[integer].y

[0167] z=(waypoints[integer+1].z-waypoints[ineger].z)*Ratio+waypoints[integer].z

[0168] Where x represents the current position of the target on the X axis, y represents the current position of the target on the Y axis, z represents the current position of the target on the Z axis, waypoints[i] represents the status information of the independent waypoint i, and waypoints[] stores the status information of all waypoints.

[0169] The target speed is:

[0170]

[0171] in,

[0172]

[0173] ν x Indicates the target's current speed on the X-axis, ν y Indicates the target's current velocity on the Y axis, ν z Indicates the target's current speed on the Z axis;

[0174] The target azimuth is:

[0175] yaw=(waypoints[integer+1].yaw-waypoints[integer].yaw)*Ratio

[0176] +waypoints[integer].yaw

[0177] Where yaw represents the azimuth of the target motion at the current moment, and waypoints[i].yaw represents the azimuth of the independent path point i;

[0178] The target pitch angle is:

[0179] pitch=(waypoints[integer+1].pitch-waypoints[integer].pitch)*Ratio

[0180] +waypoints[integer].pitch

[0181] Where pitch represents the pitch angle of the target motion at the current moment, and waypoints[i].pitch represents the pitch angle of the independent path point i;

[0182] The target roll angle is:

[0183] roll=(waypoints[integer+1].roll-waypoints[integer].roll)*Ratio

[0184] +waypoints[integer].roll

[0185] Where roll represents the roll angle of the target motion at the current moment, and waypoints[i].roll represents the roll angle of the independent path point i;

[0186] S313 , adopting a parallel processing method, using multiple threads to synchronously execute S311 to S312 to complete the dynamic parameter information of the execution time of all independent path points.

[0187] It should be noted that in reality, radars and targets exist in physical form, and in radar simulation, it is necessary to calculate the dynamic parameters between the radar and the target. In the prior art, when a single radar or a single target is used, the amount of calculation is small and the delay caused by the calculation can be ignored. However, in this application, it is necessary to simulate the echo signals between multiple radars and multiple targets. If the serial processing method in the prior art is used, a large delay will be generated. Therefore, in the technical solution provided by this application, if Figure 2 As shown in the figure, a multi-threaded parallel processing method is used to simultaneously calculate the dynamic parameters between multiple radars and multiple targets, thereby improving the computing efficiency and meeting the actual needs.

[0188] In yet another optional embodiment, the calculating and processing the wireless signal information according to the dynamic parameter information to obtain the echo signal parameter information includes:

[0189] S321, obtaining an interpolation time point;

[0190] S322: Determine whether the radar and the target are visible based on the dynamic parameter information and the interpolation time point, and obtain a first determination result;

[0191] If the first judgment result is no, executing step S321;

[0192] If the first judgment result is yes, execute step S323;

[0193] S323, calculating and processing the input environmental parameter information to obtain a path attenuation parameter;

[0194] S324. Process the input target information to obtain radar cross sections of all targets;

[0195] S325: Calculate and process the wireless signal information according to the radar scattering cross section of the target and the path attenuation parameter to obtain echo signal parameter information.

[0196] It should be noted that, through the above processing, the prediction accuracy of radar signal path power attenuation can be improved according to the actual situation of dynamic scenes.

[0197] In yet another optional embodiment, the calculating and processing the input environmental parameter information to obtain the path attenuation parameter includes:

[0198] S3231. Determine whether it is necessary to consider the impact of the environment on path attenuation, and obtain a third determination result;

[0199] If the third judgment result is no, executing step S3232;

[0200] If the third judgment result is yes, execute step S3233;

[0201] S3232: Calculate and process the wireless signal information according to the dynamic parameter information to obtain a path attenuation parameter;

[0202] The path attenuation parameter calculation is expressed as:

[0203] L s =L f +L v ;

[0204] L f =32.5+20lg (F) +20lg (D) ;

[0205]

[0206] Among them, L s represents the path attenuation parameter; L f represents the free space path attenuation; L v represents the dynamic impact path attenuation; F represents the wireless signal frequency; α, β, and γ represent the azimuth, pitch, and roll angles, respectively; c represents the speed of light; B represents the wireless signal bandwidth; and v represents the relative speed between the radar and the target.

[0207] S3233. Calculate and process the wireless signal information based on the input meteorological and water vapor parameter information and the dynamic parameter information to obtain a path attenuation parameter.

[0208] The path attenuation parameter calculation is expressed as:

[0209] L s =L f +L v +L w ;

[0210] L f =32.5+20lg (F) +20lg (D) ;

[0211]

[0212] L w =ρ w γ w,ref ;

[0213] Among them, L s represents the path attenuation parameter; L f represents the free space path attenuation; L v represents the dynamic impact path attenuation; F represents the wireless signal frequency; α, β, and γ represent the azimuth, pitch, and roll angles, respectively; c represents the speed of light; B represents the wireless signal bandwidth; v represents the relative speed between the radar and the target; ρ w Indicates water vapor density (unit: g / m 3 );γ w,ref is the water vapor attenuation coefficient at the reference frequency, γ w,ref It can be calculated using meteorological data or formulas in ITU-R Recommendations.

[0214] In yet another optional embodiment, processing the input target information to obtain radar cross sections of all targets includes:

[0215] S3241. Determine whether there is an external input target radar cross section file, and obtain a second determination result;

[0216] If the second judgment result is yes, execute step S3242;

[0217] If the second judgment result is no, executing step S3243;

[0218] S3242. Obtaining the radar cross section of the target according to an external input target radar cross section file;

[0219] S3243, calculate the radar cross section of the target based on the SwerlingX model

[0220] In yet another optional embodiment, the calculating and processing the wireless signal information based on the radar cross section of the target and the path attenuation parameter to obtain the echo signal parameter information includes:

[0221] S3251. Select any signal from the wireless signal information as a transmission signal of radar i; select any target p from the input target information;

[0222] S3252: Process the transmitted signal of the radar i according to the radar cross section of the target and the path attenuation parameter to obtain echo signal parameters;

[0223] The echo signal is expressed as:

[0224]

[0225] Where S i,echo,p (t) represents the echo signal of the target i; A i,echo,p Indicates the echo signal amplitude; S i,t (t) represents the transmitted signal of radar i; t i,echo,p represents the round-trip delay between target p and radar i; f d,i,p represents the Doppler frequency between radar i and target p;

[0226] Echo signal amplitude A i,echo,p The calculation model is:

[0227]

[0228] Where, P t represents the transmitting power of radar i; G t represents the transmitting antenna gain of radar i; G r represents the receiving antenna gain of radar i; λ i represents the wavelength of the signal sent by radar i; σ p represents the radar cross section of target p; L s represents the path attenuation parameter between radar i and target p; R i,p It represents the distance between radar i and target p when the radar i signal reaches target p. The calculation method is:

[0229] R i,p =R 0,i,p -v i,p t;

[0230] Where R 0,i,p represents the distance between target p and radar i when radar i transmits the signal; v i,p represents the target velocity between target p and radar i;

[0231] The Doppler frequency f between radar i and target p d,i,p The calculation model is:

[0232]

[0233] The round-trip delay t between target p and radar i i,echo,p The calculation model is:

[0234]

[0235] Where c represents the speed of light;

[0236] S3253, loop through steps S3251 to S3252 to complete the echo signal parameters between all radars and targets, and obtain echo signal parameter information.

[0237] In yet another optional embodiment, the step of time-synchronizing the FPGA module, the physical radar, and the digital demonstration scene, and processing the echo signal parameter information using a D / A unit in a signal processing module to obtain a simulated radar echo signal includes:

[0238] S41, time-synchronizing the FPGA module, the physical radar, and the digital demonstration scene;

[0239] It should be noted that this solution uses parallel processing and each module executes synchronously. In order to improve operating efficiency, the FPGA module, physical radar, and digital demonstration scene need to be synchronized with high precision. S42. Obtain any set of echo signal parameters from the echo signal parameter information;

[0240] S43. Use FPGA to modulate any one group of echo signal parameters to obtain a modulated signal; the modulated signal is expressed as:

[0241]

[0242] S44, looping through steps S42 to S43 to obtain a multi-channel modulated signal set;

[0243] S45. Combine the multi-channel modulated signal set to obtain a simulated radar echo signal. Specifically, a multi-channel signal combination processing model is expressed as:

[0244]

[0245] Where S i,echo (t) represents the radar i echo signal; S i,echo,p (t) represents the echo signal of target p to radar i; P represents the number of targets.

[0246] Example 2

[0247] See also Figure 3 . Figure 3 This is a structural diagram of a real-time radar echo signal simulation device based on digital storage disclosed in an embodiment of the present invention.

[0248] like Figure 3 As shown, an embodiment of the present invention discloses a real-time radar echo signal simulation device based on digital storage, which is used to implement a real-time radar echo signal simulation method based on digital storage as disclosed in the first aspect of the embodiment of the present invention. The device includes:

[0249] External scene input module 201; for receiving scene information input by the user, and using the input scene information to establish digital demonstration scene information, and inputting the digital demonstration scene information into the echo parameter calculation module;

[0250] Signal processing module 202; using FPGA unit, A / D unit and D / A unit to process and store signals and generate analog echo signals; the FPGA unit includes a processor and a memory for signal calculation, processing and storage, such as Figure 4 As shown, the FPGA unit includes a memory 301 and a processor 302; the A / D unit is used to convert the wireless signal from an analog signal to a digital signal; the D / A unit is used to convert the wireless signal from a digital signal to an analog signal;

[0251] The echo parameter processing module 203 is used to calculate the echo signal parameter information according to the digital demonstration scene information and the wireless signal;

[0252] Physical radar module 204; the physical radar module represents a radar that exists in a physical sense and is used to transmit radar wireless signals and receive echo signals.

[0253] The device embodiments described above are merely illustrative. Modules described as separate components may or may not be physically separate, and components shown as modules may or may not be physical modules, i.e., they may be located in one place or distributed across multiple network modules. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0254] Through the detailed description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus the necessary general hardware platform, or of course, by means of hardware. Based on this understanding, the above technical solution, in essence, or the portion that contributes to the prior art, can be embodied in the form of a software product, which can be stored in a computer-readable storage medium, including a read-only memory (ROM), a random access memory (RAM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), a one-time programmable read-only memory (OTPROM), an electronically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disk storage, magnetic disk storage, magnetic tape storage, or any other computer-readable medium capable of carrying or storing data.

[0255] Finally, it should be noted that the method and device for simulating real-time radar echo signals based on digital storage disclosed in the embodiments of the present invention are only preferred embodiments of the present invention, and are only used to illustrate the technical solutions of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the aforementioned embodiments, it should be understood by those skilled in the art that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A real-time radar echo signal simulation method based on digital storage, characterized in that: The method comprises: S1. Establishing digital demonstration scene information based on scene information obtained by an external scene input module; the digital demonstration scene information includes information of a plurality of independent path points; S2. Using the signal processing module, obtain wireless signals from the physical radar, process and store them, and obtain wireless signal information; S3. Processing the wireless signal using an echo parameter processing module using a parallel computing method according to the digital demonstration scene information to obtain echo signal parameter information; the echo signal parameters include echo signal amplitude, Doppler frequency, and round-trip delay; S4. Time-synchronize the FPGA module, the physical radar, and the digital demonstration scene, and use the D / A unit in the signal processing module to process the echo signal parameter information to obtain a simulated radar echo signal.

2. The method for simulating real-time radar echo signals based on digital storage according to claim 1, characterized in that: The signal processing module is used to obtain wireless signals from the physical radar, and the wireless signal information is obtained after processing and storage, including: S21. Collect and store radio frequency signals emitted by the physical radar device; S22, using the A / D unit in the signal processing module to sample the collected radio frequency signal to obtain a discrete signal; S23. Analyze the discrete signal to obtain a discrete signal sequence; the discrete signal sequence includes a real-valued IQ sequence and an amplitude and phase AP sequence; S24. Detect and process the discrete signal sequence to obtain wireless signal information, and store it in the internal storage space of the FPGA unit.

3. The method for simulating real-time radar echo signals based on digital storage according to claim 1, characterized in that: The method of processing the wireless signal using an echo parameter processing module according to the digital demonstration scene information to obtain echo signal parameter information includes: S31, processing the independent path point parameter information through high-order modeling according to the digital demonstration scene information to obtain dynamic parameter information; S32. Calculate and process the wireless signal information according to the dynamic parameter information to obtain echo signal parameter information.

4. The method for simulating real-time radar echo signals based on digital storage according to claim 1, characterized in that: The method of processing the independent path point parameter information by high-order modeling based on the digital demonstration scene information to obtain dynamic parameter information includes: S311, performing time difference processing on the simulation time of the digital demonstration scene information and the acquisition time of the wireless signal information to obtain a time difference value and a time difference coefficient; The time difference value is expressed as: remaining=t-time_vec[integer]; The time difference coefficient is expressed as: Ratio=remaind / ((time_vec[integer+1]-time_vec[integer])); Where t represents the current time of the platform being sought, integer represents the number of the independent path point interval at the current time, time_vec[i] represents the time information of the independent path point i, and time_vec[] stores the time information of the independent path point; S312. Process the independent path point parameter information according to the time difference value and the time difference coefficient to obtain target dynamic parameter information; the target dynamic parameter information includes target position, target speed, target azimuth, target pitch angle, and target roll angle; The target location is: x=(waypoints[integer+1].x-waypoints[ineger].x)*Ratio+waypoints[integer].x y=(waypoints[integer+1].y-waypoints[ineger].y)*Ratio+waypoints[integer].y z=(waypoints[integer+1].z-waypoints[ineger].z)*Ratio+waypoints[integer].z Where x represents the current position of the target on the X axis, y represents the current position of the target on the Y axis, z represents the current position of the target on the Z axis, waypoints[i] represents the status information of the independent waypoint i, and waypoints[] stores the status information of all waypoints. The target speed is: in, ν x Indicates the target's current speed on the X-axis, ν y Indicates the target's current velocity on the Y axis, ν z Indicates the target's current speed on the Z axis; The target azimuth is: yaw=(waypoints[integer+1].yaw-waypoints[integer].yaw)*Ratio +waypoints[integer].yaw Where yaw represents the azimuth of the target motion at the current moment, and waypoints[i].yaw represents the azimuth of the independent path point i; The target pitch angle is: pitch=(waypoints[integer+1].pitch-waypoints[integer].pitch)*Ratio +waypoints[integer].pitch Where pitch represents the pitch angle of the target motion at the current moment, and waypoints[i].pitch represents the pitch angle of the independent path point i; The target roll angle is: roll=(waypoints[integer+1].roll-waypoints[integer].roll)*Ratio +waypoints[integer].roll Where roll represents the roll angle of the target motion at the current moment, and waypoints[i].roll represents the roll angle of the independent path point i; S313 , adopting a parallel processing method, using multiple threads to synchronously execute S311 to S312 to complete the dynamic parameter information of the execution time of all independent path points.

5. The method for simulating real-time radar echo signals based on digital storage according to claim 1, characterized in that: The calculating and processing the wireless signal information according to the dynamic parameter information to obtain the echo signal parameter information includes: S321, obtaining an interpolation time point; S322: Determine whether the radar and the target are visible based on the dynamic parameter information and the interpolation time point, and obtain a first determination result; If the first judgment result is no, executing step S321; If the first judgment result is yes, execute step S323; S323, calculating and processing the input environmental parameter information to obtain a path attenuation parameter; S324. Process the input target information to obtain radar cross sections of all targets; S325: Calculate and process the wireless signal information according to the radar scattering cross section of the target and the path attenuation parameter to obtain echo signal parameter information.

6. The method for simulating real-time radar echo signals based on digital storage according to claim 5, characterized in that: The input target information is processed to obtain radar cross sections of all targets, including: S3241. Determine whether there is an external input target radar cross section file, and obtain a second determination result; If the second judgment result is yes, execute step S3242; If the second judgment result is no, executing step S3243; S3242. Obtaining the radar cross section of the target according to an external input target radar cross section file; S3243. Calculate the radar cross section of the target using a preset radar cross section calculation model.

7. The method for simulating real-time radar echo signals based on digital storage according to claim 5, characterized in that: The calculating and processing the wireless signal information according to the radar scattering cross section of the target and the path attenuation parameter to obtain the echo signal parameter information includes: S3251. Select any signal from the wireless signal information as a transmission signal of radar i; select any target p from the input target information; S3252: Process the transmitted signal of the radar i according to the radar cross section of the target and the path attenuation parameter to obtain echo signal parameters; The echo signal is expressed as: Where S i,echo,p (t) represents the echo signal of the target i; A i,echo,p Indicates the echo signal amplitude; S i,t (t) represents the transmitted signal of radar i; t i,echo,p represents the round-trip delay between target p and radar i; f d,i,p represents the Doppler frequency between radar i and target p; Echo signal amplitude A i,echo,p The calculation model is: Where, P t represents the transmitting power of radar i; G t represents the transmitting antenna gain of radar i; G r represents the receiving antenna gain of radar i; λ i represents the wavelength of the signal sent by radar i; σ p represents the radar cross section of target p; L s represents the path attenuation parameter between radar i and target p; R i,p It represents the distance between radar i and target p when the radar i signal reaches target p. The calculation method is: R i,p =R 0,i,p -v i,p t; Where R 0,i,p represents the distance between target p and radar i when radar i transmits the signal; v i,p Indicates the target speed; The Doppler frequency f between radar i and target p d,i,p The calculation model is: The round-trip delay t between target p and radar i i,echo,p The calculation model is: Where c represents the speed of light; S3253, loop through steps S3251 to S3252 to complete the echo signal parameters between all radars and targets, and obtain echo signal parameter information.

8. The method for simulating real-time radar echo signals based on digital storage according to claim 1, characterized in that: The FPGA module, the physical radar, and the digital demonstration scene are time-synchronized, and the echo signal parameter information is processed using the D / A unit in the signal processing module to obtain a simulated radar echo signal, including: S41, time-synchronizing the FPGA module, the physical radar, and the digital demonstration scene; S42. Acquire any set of echo signal parameters from the echo signal parameter information; S43. Use FPGA to modulate any one group of echo signal parameters to obtain a modulated signal; the modulated signal is expressed as: S44, looping through steps S42 to S43 to obtain a multi-channel modulated signal set; S45 , combining the multi-path modulated signal set to obtain a simulated radar echo signal.

9. A real-time radar echo signal simulation device based on digital storage, characterized in that: For implementing the method for simulating real-time radar echo signals based on digital storage according to any one of claims 1 to 8, the device comprises: External scene input module; used to receive scene information input by the user, and use the input scene information to establish digital demonstration scene information, and input the digital demonstration scene information into the echo parameter calculation module; Signal processing module; using FPGA unit, A / D unit and D / A unit to perform signal processing and storage to generate analog echo signal; the FPGA unit includes a processor and memory for signal calculation, processing and storage; the A / D unit is used to convert the wireless signal from analog signal to digital signal; the D / A unit is used to convert the wireless signal from digital signal to analog signal; Echo parameter processing module; used to calculate echo signal parameter information based on digital demonstration scene information and wireless signals; Physical radar module; the physical radar module represents a radar that exists in a physical sense and is used to transmit radar wireless signals and receive echo signals.

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