A method and apparatus for simulating real-time radar echo signals based on digital storage

Abstract

This invention discloses a method and apparatus for simulating real-time radar echo signals based on digital storage. The method includes: establishing digital demonstration scene information based on scene information acquired by an external scene input module; collecting, processing, and storing physical radar wireless signals to obtain wireless signal information; processing the wireless signals using an echo parameter module based on the digital demonstration scene information to obtain echo signal parameter information; synchronizing the FPGA module, physical radar, and digital demonstration scene in time, and processing the echo signal parameter information using a signal processing module to obtain simulated radar echo signals. The method employs efficient parallel computation of parameters such as multiple radars, multiple targets, and multiple paths, improving high-speed real-time simulation of echo signals. This invention uses a combination of parallel computing software modeling and FPGA simulation, resulting in higher efficiency, greater flexibility, and more accurate calculations.

Description

Technical Field

[0001] This invention relates to the field of signal processing technology, and specifically to a method and apparatus for simulating real-time radar echo signals based on digital storage. Background Technology

[0002] Modern radar systems are increasingly widely used in both military and civilian fields, and their functions are becoming increasingly complex. For example, in the military field, multi-radar cooperative combat systems can achieve comprehensive monitoring and precision strikes in complex battlefield environments; in the civilian field, multi-radar systems can be used for air traffic control, weather monitoring, and other applications. These applications all require radar systems to be able to process multiple targets simultaneously and to dynamically track and identify these targets.

[0003] Radar echo signal simulation is used to model and simulate the spatial propagation effects of radar radio frequency signals, assisting in the testing of radar functions and performance. With the rapid development and progress in the field of electronic information, various types of radar and other electronic devices are constantly emerging, making the electromagnetic environment increasingly complex and posing greater challenges to wireless signal simulation. To adapt to complex electromagnetic environments, radar echo signal simulation needs to be able to simulate scenarios where multiple radars operate simultaneously, model the position and velocity of moving platforms such as radars, targets, and interference sources, simulate the radar cross-section and other characteristics of target signal reflection, model target echo signals using radio frequency signal propagation theory models, model echo signals with various backgrounds, obtain signal parameter data consisting of target echo signal amplitude, Doppler, and phase parameters, and transmit this data to the signal generation device to achieve signal waveform output.

[0004] Traditional radar echo simulation methods primarily focus on simulating a single radar targeting a single target, failing to meet the demands of complex scenarios involving multiple radars and multiple targets. Furthermore, they exhibit significant limitations in simulating dynamic scenarios. The dynamic characteristics of radar targets (such as trajectory and velocity changes) are crucial aspects of radar system performance evaluation, but existing simulation methods often only simulate static or simply moving targets, failing to realistically reflect the characteristics of radar targets in complex dynamic environments. Additionally, dynamic simulation of multiple radars and multiple targets requires high real-time performance to ensure that the simulation results accurately reflect the actual operating state of the radar system. However, existing methods often suffer from insufficient real-time performance when handling complex scenarios, failing to meet the needs of practical applications. Summary of the Invention

[0005] The main purpose of this invention is to address the shortcomings of existing simulation methods in terms of dynamic scene simulation and real-time performance, and to achieve accurate simulation of dynamic scenes involving multiple radars and multiple targets.

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

[0007] S1. Based on the scene information obtained from the external scene input module, establish digital demonstration scene information; the digital demonstration scene information includes several independent path point information; 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, wireless signals are acquired from the physical radar, processed, and stored to obtain wireless signal information;

[0009] S3. Based on the digital demonstration scenario information, a parallel computing method is used to process the wireless signal using the echo parameter processing module to obtain echo signal parameter information; the echo signal parameters include echo signal amplitude, Doppler frequency, and two-way delay;

[0010] S4. Synchronize the FPGA module, physical radar, and digital demonstration scene in time. 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, in the first aspect of the present invention, the step of using a signal processing module to acquire wireless signals from a physical radar, processing and storing them to obtain wireless signal information includes:

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

[0013] S22. Using the A / D unit in the signal processing module, the acquired radio frequency signal is sampled to obtain a discrete signal;

[0014] Assuming the total sampling time of a continuous signal is T and the discrete time length is L, then the corresponding discrete signal... Represented as:

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

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

[0017] S23. Perform analytical processing on 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 as follows:

[0022]

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

[0024]

[0025] S24. The discrete signal sequence is detected and processed to obtain wireless signal information, which is then stored in the internal storage space of the FPGA unit.

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

[0027] S241. Process the discrete signal sequence to obtain the pulse period;

[0028] S242. According to the threshold detection model, the wireless signal information is obtained through threshold comparison;

[0029] The single pulse period signal is:

[0030]

[0031] In the formula, thi is the set detection threshold; T p The pulse period;

[0032] The pulse period T p Based on 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 periods.

[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 the work efficiency.

[0035] As an optional implementation, in the first aspect of the present invention, the step of processing the wireless signal using a parallel computing method and an echo parameter processing module based on the digital demonstration scenario information to obtain echo signal parameter information includes:

[0036] S31. Based on the digital demonstration scene information, through high-order modeling, the independent path point parameter information is processed to obtain dynamic parameter information;

[0037] S32. Based on the dynamic parameter information, the wireless signal information is calculated and processed to obtain the echo signal parameter information.

[0038] As an optional implementation, in the first aspect of the present invention, the step of processing the independent path point parameter information through high-order modeling based on the digital demonstration scene information to obtain dynamic parameter information includes:

[0039] S311. Perform time difference processing on the simulation time of the digital demonstration scene information and the acquisition time of the wireless signal information to obtain the time difference value and 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] In the formula, t represents the current time of the platform, integer represents the interval number of the independent path point at the current time, and time_vec[i] represents the time information of the independent path point i. The time_vec[] stores the time information of the independent path point.

[0045] S312. Based on the time difference value and time difference coefficient, the independent path point parameter information is processed to obtain target dynamic parameter information, which includes target position, target speed, target azimuth angle, 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] In the formula, x represents the position information of the target on the X-axis at the current time, y represents the position information of the target on the Y-axis at the current time, z represents the position information of the target on the Z-axis at the current time, waypoints[i] represents the state information of the independent path point i, and waypoints[] stores the state information of all waypoints;

[0051] The target speed is:

[0052]

[0053] in,

[0054]

[0055] ν x ν represents the target's velocity on the X-axis at the current moment. y ν represents the target's velocity on the Y-axis at the current moment. z This represents the target's velocity along the Z-axis at the current moment.

[0056] The target azimuth angle is:

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

[0058] +waypoints[integer].yaw

[0059] In the formula, yaw represents the azimuth angle of the target's motion at the current moment, and waypoints[i].yaw represents the azimuth angle of 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] In the formula, 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] In the formula, roll represents the roll angle of the target motion at the current moment, and waypoints[i].roll represents the roll angle of independent path point i;

[0068] S313. Parallel processing is adopted, and multi-threaded synchronous execution of S311 to S312 is used to complete the dynamic parameter information of the execution time of all independent path points.

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

[0070] S321. Obtain the interpolation time point;

[0071] S322. Based on the dynamic parameter information and interpolation time points, determine whether the radar and the target are visible to each other, and obtain the first judgment result;

[0072] If the first judgment result is negative, then proceed to step S321;

[0073] If the first judgment result is yes, then proceed to step S323;

[0074] S323. Calculate and process the input environmental parameter information to obtain the path attenuation parameter;

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

[0076] S325. Based on the radar cross section of the target and the path attenuation parameters, the wireless signal information is calculated and processed to obtain echo signal parameter information.

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

[0078] S3241. Determine if there is an externally input target radar cross section file to obtain the second determination result;

[0079] If the second judgment result is yes, then proceed to step S3242;

[0080] If the second judgment result is negative, then proceed to step S3243;

[0081] S3242. Obtain the radar cross section of the target based on the externally 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 can be the SwellingX model.

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

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

[0085] S3252. Based on the radar cross section of the target and the path attenuation parameters, the transmitted signal of radar i is processed to obtain the echo signal parameters;

[0086] The echo signal is represented as:

[0087]

[0088] In the formula, S i,echo,p (t) represents the echo signal of target i; A i,echo,p Indicates the amplitude of the echo signal; S i,t (t) represents the transmitted signal of radar i; t i,echo,p f represents the two-way time delay between target p and radar i; d,i,p This represents the Doppler frequency between radar i and target p;

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

[0090]

[0091] In the formula, P t G represents the transmit power of radar i; t G represents the transmit antenna gain of radar i; r λ represents the receiving antenna gain of radar i; i σ represents the wavelength of the signal transmitted by radar i; p L represents the radar cross section of target p; s R represents the path attenuation parameter between radar i and target p; i,p This represents the distance between radar i and target p when radar i's signal arrives at target p. The calculation method is as follows:

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

[0093] In the formula, R 0,i,p This represents the distance between target p and radar i when radar i transmits a signal; v i,p This 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 as follows:

[0095]

[0096] Two-way time delay t between target p and radar i i,echo,p The calculation model is as follows:

[0097]

[0098] In the formula, c represents the speed of light;

[0099] S3253. Repeatedly execute steps S451 to S452 to complete all echo signal parameters between the radar and the target, and obtain echo signal parameter information.

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

[0101] S41. Synchronize the FPGA module, physical radar, and digital demonstration scene in time;

[0102] It should be noted that this solution employs parallel processing, with each module executing synchronously. To improve operational efficiency, the FPGA module, physical radar, and digital demonstration scene need to be synchronized with high precision in time.

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

[0104] S43. Modulate any set of echo signal parameters using an FPGA to obtain a modulated signal; the modulated signal is represented as follows:

[0105]

[0106] S44. Repeat steps S42 to S43 to obtain a set of multi-channel modulated signals;

[0107] S45. The multi-channel modulated signal set is combined to obtain a simulated radar echo signal. Specifically, the multi-channel signal combining model is expressed as follows:

[0108]

[0109] In the formula, 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 this invention discloses a digital storage-based real-time radar echo signal simulation device for implementing a digital storage-based real-time radar echo signal simulation method as disclosed in the first aspect of this invention. The device includes:

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

[0112] The signal processing module utilizes an FPGA unit, an A / D unit, and a D / A unit to process and store signals, generating analog echo signals. The FPGA unit includes a processor and a memory for signal calculation, processing, and storage. The A / D unit converts the wireless signal from analog to digital. The D / A unit converts the wireless signal from digital to analog.

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

[0114] A physical radar module; the physical radar module represents a radar 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] This invention discloses a method and apparatus for simulating real-time radar echo signals based on digital storage. Based on FPGA resources for real-time acquisition, storage, and signal processing, this invention acquires radar output RF signals in real time, maps changes in software-modeled calculation parameters to the generated radar echo signals in real time, and directly simulates and generates the radar echo signals using the FPGA, fully leveraging the flexibility of radar simulation technology. This application provides solutions for relative changes in parameters such as signal amplitude, frequency, and time delay caused by signal propagation, multi-point target reflection attenuation, and dynamic changes between the target and the radar. Compared to current software simulation technology, using FPGA to increase spatial physical signal output provides higher characteristics of radar echo signals; compared to simple hardware simulation sources, the combined software modeling + FPGA simulation method offers greater flexibility and more accurate calculation precision. Therefore, this invention proposes a complete architecture and method for radar echo simulation and signal parameter modulation, applicable to tasks such as radar signal modeling, propagation modeling, and radar testing in complex scenarios. In this architecture, parallel computing and multi-threading are employed to further improve efficiency and enhance simulation realism. Attached Figure Description

[0117] Figure 1 This is a schematic diagram of a method for simulating real-time radar echo signals based on digital storage, as disclosed in an embodiment of the present invention.

[0118] Figure 2 This is a schematic diagram of parallel computation for signal parameter processing disclosed in an embodiment of the present invention;

[0119] Figure 3 This is a schematic 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 an FPGA module structure disclosed in an embodiment of the present invention. Detailed Implementation

[0121] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0122] Example 1

[0123] Please see Figure 1 . Figure 1 This is a schematic diagram of the 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 in the embodiment of the present invention, a method for simulating real-time radar echo signals based on digital storage is disclosed. The method includes:

[0125] S1. Based on the scene information obtained from the external scene input module, establish digital demonstration scene information; the digital demonstration scene information includes several independent path point information; 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, wireless signals are acquired from a physical radar, processed, and stored to obtain wireless signal information; the physical radar represents a radar that exists in a physical sense.

[0127] S3. Based on the digital demonstration scenario information, a parallel computing method is used to process the wireless signal using the echo parameter processing module to obtain echo signal parameter information; the echo signal parameters include echo signal amplitude, Doppler frequency, and two-way delay;

[0128] S4. Synchronize the FPGA module, physical radar, and digital demonstration scene in time. 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 step of using a signal processing module to acquire wireless signals from a physical radar, processing and storing them to obtain wireless signal information includes:

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

[0131] S22. Using the A / D unit in the signal processing module, the acquired radio frequency signal is sampled to obtain a discrete signal;

[0132] Assuming the total sampling time of a continuous signal is T and the discrete time length is L, then the corresponding discrete signal... Represented as:

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

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

[0135] S23. Perform analytical processing on 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 as follows:

[0140]

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

[0142]

[0143] S24. The discrete signal sequence is detected and processed to obtain wireless signal information, which is then stored in the internal storage space of the FPGA unit.

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

[0145] S241. Process the discrete signal sequence to obtain the pulse period;

[0146] S242. According to the threshold detection model, the wireless signal information is obtained through threshold comparison;

[0147] The single pulse period signal is:

[0148]

[0149] In the formula, thi is the set detection threshold; T p The pulse period;

[0150] The pulse period T p Based on 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 periods.

[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 the work efficiency.

[0153] In another optional embodiment, the step of processing the wireless signal using a parallel computing method based on the digital demonstration scenario information and employing an echo parameter processing module to obtain echo signal parameter information includes:

[0154] S31. Based on the digital demonstration scene information, through high-order modeling, the independent path point parameter information is processed to obtain dynamic parameter information;

[0155] S32. Based on the dynamic parameter information, the wireless signal information is calculated and processed to obtain the echo signal parameter information.

[0156] In another optional embodiment, the step of processing the independent path point parameter information to obtain dynamic parameter information through high-order modeling based on the digital demonstration scene information includes:

[0157] S311. Perform time difference processing on the simulation time and the acquisition time of the wireless signal information in the digital demonstration scene information to obtain the time difference value and the 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] In the formula, t represents the current time of the platform, integer represents the interval number of the independent path point at the current time, and time_vec[i] represents the time information of the independent path point i. The time_vec[] stores the time information of the independent path point.

[0163] S312. Based on the time difference value and time difference coefficient, the independent path point parameter information is processed to obtain target dynamic parameter information, which includes target position, target speed, target azimuth angle, 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] In the formula, x represents the position information of the target on the X-axis at the current time, y represents the position information of the target on the Y-axis at the current time, z represents the position information of the target on the Z-axis at the current time, waypoints[i] represents the state information of the independent path point i, and waypoints[] stores the state information of all waypoints;

[0169] The target speed is:

[0170]

[0171] in,

[0172]

[0173] ν x ν represents the target's velocity on the X-axis at the current moment. y ν represents the target's velocity on the Y-axis at the current moment. z This represents the target's velocity along the Z-axis at the current moment.

[0174] The target azimuth angle is:

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

[0176] +waypoints[integer].yaw

[0177] In the formula, yaw represents the azimuth angle of the target's motion at the current moment, and waypoints[i].yaw represents the azimuth angle of 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] In the formula, 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] In the formula, roll represents the roll angle of the target motion at the current moment, and waypoints[i].roll represents the roll angle of independent path point i;

[0186] S313. Parallel processing is adopted, and multi-threaded synchronous execution of S311 to S312 is used to complete the dynamic parameter information of the execution time of all independent path points.

[0187] It should be noted that in reality, radar and targets exist in physical form. Radar simulation requires calculating the dynamic parameters between the radar and the target. In existing technologies, when using a single radar or target, the computational load is small and the resulting time delay is negligible. However, this application requires simulating echo signals between multiple radars and multiple targets. If the existing serial processing method is used, it will result in a significant time delay. Therefore, in the technical solution provided in this application, if... Figure 2 As shown, a multi-threaded parallel processing method is adopted to simultaneously calculate the dynamic parameters between multiple radars and multiple targets, thereby improving computational efficiency and meeting practical requirements.

[0188] In another optional embodiment, the step of calculating and processing the wireless signal information based on the dynamic parameter information to obtain the echo signal parameter information includes:

[0189] S321. Obtain the interpolation time point;

[0190] S322. Based on the dynamic parameter information and interpolation time points, determine whether the radar and the target are visible to each other, and obtain the first judgment result;

[0191] If the first judgment result is negative, then proceed to step S321;

[0192] If the first judgment result is yes, then proceed to step S323;

[0193] S323. Calculate and process the input environmental parameter information to obtain the path attenuation parameter;

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

[0195] S325. Based on the radar cross section of the target and the path attenuation parameters, the wireless signal information is calculated and processed to obtain echo signal parameter information.

[0196] It should be noted that the above processing steps can improve the prediction accuracy of radar signal path power attenuation based on the actual dynamic scene conditions.

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

[0198] S3231. Determine whether the impact of the environment on path decay needs to be considered, and obtain the third judgment result;

[0199] If the third judgment result is negative, then step S3232 is executed;

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

[0201] S3232. Based on the dynamic parameter information, the wireless signal information is calculated and processed to obtain the path attenuation parameter;

[0202] The path attenuation parameter is calculated as follows:

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

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

[0205]

[0206] Among them, L s L represents the path attenuation parameter. f Indicates free space path decay; L v The dynamic path attenuation is indicated by F; the radio frequency is indicated by F; α, β, and γ represent the azimuth, elevation, and roll angles, respectively; c represents the speed of light; B represents the radio signal bandwidth; and v represents the relative speed between the radar and the target.

[0207] S3233. Based on the input meteorological and water vapor parameter information, the dynamic parameter information, the wireless signal information is calculated and processed to obtain the path attenuation parameter;

[0208] The path attenuation parameter is calculated as follows:

[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 L represents the path attenuation parameter. f Indicates free space path decay; L v Indicates dynamic path attenuation; F represents the radio frequency; α, β, and γ represent the azimuth, elevation, and roll angles, respectively; c represents the speed of light; B represents the radio signal bandwidth; v represents the relative velocity between the radar and the target; ρ w Water vapor density (unit: g / m³) 3 );γ w,ref It 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, the processing of the input target information to obtain the radar cross sections of all targets includes:

[0215] S3241. Determine if there is an externally input target radar cross section file to obtain the second determination result;

[0216] If the second judgment result is yes, then proceed to step S3242;

[0217] If the second judgment result is negative, then proceed to step S3243;

[0218] S3242. Obtain the radar cross section of the target based on the externally input target radar cross section file;

[0219] S3243. Calculate the target's radar cross section based on the Swelling X model.

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

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

[0222] S3252. Based on the radar cross section of the target and the path attenuation parameters, the transmitted signal of radar i is processed to obtain the echo signal parameters;

[0223] The echo signal is represented as:

[0224]

[0225] In the formula, S i,echo,p (t) represents the echo signal of target i; A i,echo,p Indicates the amplitude of the echo signal; S i,t (t) represents the transmitted signal of radar i; t i,echo,p f represents the two-way time delay between target p and radar i; d,i,p This represents the Doppler frequency between radar i and target p;

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

[0227]

[0228] In the formula, P t G represents the transmit power of radar i; t G represents the transmit antenna gain of radar i; r λ represents the receiving antenna gain of radar i; i σ represents the wavelength of the signal transmitted by radar i; p L represents the radar cross section of target p; s R represents the path attenuation parameter between radar i and target p; i,p This represents the distance between radar i and target p when radar i's signal arrives at target p. The calculation method is as follows:

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

[0230] In the formula, R 0,i,p This represents the distance between target p and radar i when radar i transmits a signal; v i,p This 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 as follows:

[0232]

[0233] Two-way time delay t between target p and radar i i,echo,p The calculation model is as follows:

[0234]

[0235] In the formula, c represents the speed of light;

[0236] S3253. Repeatedly execute steps S3251 to S3252 to complete all echo signal parameters between the radar and the target, and obtain echo signal parameter information.

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

[0238] S41. Synchronize the FPGA module, physical radar, and digital demonstration scene in time;

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

[0240] S43. Modulate any set of echo signal parameters using an FPGA to obtain a modulated signal; the modulated signal is represented as follows:

[0241]

[0242] S44. Repeat steps S42 to S43 to obtain a set of multi-channel modulated signals;

[0243] S45. The multi-channel modulated signal set is combined to obtain a simulated radar echo signal. Specifically, the multi-channel signal combining model is expressed as follows:

[0244]

[0245] In the formula, 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] Please see Figure 3 . Figure 3 This is a schematic diagram of a real-time radar echo signal simulation device based on digital storage, as 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, used to implement a real-time radar echo signal simulation method based on digital storage as disclosed in the first aspect of the present invention. The device includes:

[0249] External scene input module 201; 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 to the echo parameter calculation module;

[0250] Signal processing module 202; utilizes an FPGA unit, an A / D unit, and a D / A unit to perform signal processing and storage, generating 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 wireless signals from analog to digital signals; the D / A unit is used to convert wireless signals from digital to analog signals.

[0251] Echo parameter processing module 203; used to calculate echo signal parameter information based on digital demonstration scene information and wireless signals;

[0252] Physical radar module 204; the physical radar module represents a radar 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. The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical modules; that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0254] Through the detailed description of the above embodiments, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, including read-only memory (ROM), random access memory (RAM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), one-time programmable read-only memory (OTPROM), electrically-Erasable Programmable Read-Only Memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disc storage, disk storage, magnetic tape storage, or any other computer-readable medium that can be used to carry or store data.

[0255] Finally, it should be noted that the method and apparatus for simulating real-time radar echo signals based on digital storage disclosed in the embodiments of the present invention are merely preferred embodiments of the present invention and are only used to illustrate the technical solutions of the present invention, not to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for simulating real-time radar echo signals based on digital storage, characterized in that, The method includes: S1. Based on the scene information obtained from the external scene input module, establish digital demonstration scene information; the digital demonstration scene information includes several independent path point information; S2. Using the signal processing module, wireless signals are acquired from the physical radar, processed, and stored to obtain wireless signal information; S3. Based on the digital demonstration scenario information, a parallel computing method is used to process the wireless signal using the echo parameter processing module to obtain echo signal parameter information; specifically: S31. Based on the digital demonstration scene information, through high-order modeling, the independent path point parameter information is processed to obtain dynamic parameter information, including: S311. Perform time difference processing on the simulation time of the digital demonstration scene information and the acquisition time of the wireless signal information to obtain the time difference value and time difference coefficient; The time difference value is expressed as: ； The time difference coefficient is expressed as: ； In the formula, t Indicates the current moment of the requested platform. This indicates the index of the independent path point interval at the current time. Indicates independent path points The time information, the It stores the time information of independent path points; S312. Based on the time difference value and the time difference coefficient, the independent path point parameter information is processed to obtain target dynamic parameter information; the target dynamic parameter information includes target position, target speed, target azimuth angle, target pitch angle, and target roll angle; The target location is: In the formula, This indicates the target's current position on the X-axis. This indicates the target's current position on the Y-axis. This indicates the target's current position on the Z-axis. This represents the state information of the independent path point i. It stores the status information of all waypoints; The target speed is: ； in, This represents the target's velocity on the X-axis at the current moment. This represents the target's velocity on the Y-axis at the current moment. This represents the target's velocity along the Z-axis at the current moment. The target azimuth angle is: In the formula, This indicates the azimuth angle of the target's motion at the current moment. Indicates independent path points The azimuth angle; The target pitch angle is: In the formula, This represents the pitch angle of the target motion at the current moment. Indicates independent path points The pitch angle; The target roll angle is: In the formula, This represents the roll angle of the target motion at the current moment. Indicates the roll angle of independent path point i; S313. Parallel processing is adopted, and multi-threaded synchronous execution of S311 to S312 is used to complete the dynamic parameter information of the execution time of all independent path points. S32. Based on the dynamic parameter information, the wireless signal information is calculated and processed to obtain echo signal parameter information; the echo signal parameters include echo signal amplitude, Doppler frequency, and two-way delay; S4. Synchronize the FPGA module, physical radar, and digital demonstration scene in time. 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 method of using a signal processing module to acquire wireless signals from a physical radar, processing and storing them to obtain wireless signal information includes: S21. Collect and store the radio frequency signals emitted by the physical radar equipment; S22. Using the A / D unit in the signal processing module, the acquired radio frequency signal is sampled to obtain a discrete signal; S23. Perform analytical processing on 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. The discrete signal sequence is detected and processed to obtain wireless signal information, which is then stored 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 step of calculating and processing the wireless signal information based on the dynamic parameter information to obtain echo signal parameter information includes: S321. Obtain the interpolation time point; S322. Based on the dynamic parameter information and interpolation time points, determine whether the radar and the target are visible to each other, and obtain the first judgment result; If the first judgment result is negative, then proceed to step S321; If the first judgment result is yes, then proceed to step S323; S323. Calculate and process the input environmental parameter information to obtain the path attenuation parameter; S324. Process the input target information to obtain the radar cross section of all targets; S325. Based on the radar cross section of the target and the path attenuation parameters, the wireless signal information is calculated and processed to obtain echo signal parameter information.

4. The method for simulating real-time radar echo signals based on digital storage according to claim 3, characterized in that, The process of processing the input target information to obtain the radar cross sections of all targets includes: S3241. Determine if there is an externally input target radar cross section file to obtain the second determination result; If the second judgment result is yes, then proceed to step S3242; If the second judgment result is negative, then proceed to step S3243; S3242. Obtain the radar cross section of the target based on the externally input target radar cross section file; S3243. Calculate the target's radar cross section using a preset radar cross section calculation model.

5. The method for simulating real-time radar echo signals based on digital storage according to claim 3, characterized in that, The step of calculating and processing the wireless signal information based on the radar cross section of the target and the path attenuation parameters to obtain echo signal parameter information includes: S3251. Select any signal from the wireless signal information as the transmission signal of radar i; select any target p from the input target information; S3252. Based on the radar cross section of the target and the path attenuation parameters, the transmitted signal of radar i is processed to obtain the echo signal parameters; The echo signal is represented as: In the formula, This represents the echo signal of target i; Indicates the amplitude of the echo signal; This indicates the transmitted signal of radar i; This represents the two-way time delay between target p and radar i; This represents the Doppler frequency between radar i and target p; echo signal amplitude The calculation model is as follows: ； In the formula, This indicates the transmit power of radar i; This represents the transmit antenna gain of radar i; This represents the receiving antenna gain of radar i; Indicates the wavelength of the signal transmitted by radar i; The radar cross section of target p; This represents the path attenuation parameter between radar i and target p; This represents the distance between radar i and target p when radar i's signal arrives at target p. The calculation method is as follows: ； In the formula, This represents the distance between target p and radar i when radar i transmits a signal; Indicates the target speed; Doppler frequency between radar i and target p The calculation model is as follows: ； Two-way time delay between target p and radar i The calculation model is as follows: ； In the formula, Represents the speed of light; S3253. Repeatedly execute steps S3251 to S3252 to complete all echo signal parameters between the radar and the target, and 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 process of synchronizing the FPGA module, physical radar, and digital demonstration scene in time, and processing the echo signal parameter information using the D / A unit in the signal processing module to obtain a simulated radar echo signal includes: S41. Synchronize the FPGA module, physical radar, and digital demonstration scene in time; S42. Obtain any set of echo signal parameters from the echo signal parameter information; S43. Modulate any set of echo signal parameters using an FPGA to obtain a modulated signal; the modulated signal is represented as follows: S44. Repeat steps S42 to S43 to obtain a set of multi-channel modulated signals; S45. The multi-channel modulated signal set is combined to obtain a simulated radar echo signal.

7. A real-time radar echo signal simulation device based on digital storage, characterized in that, The apparatus for implementing the real-time radar echo signal simulation method based on digital storage as described in any one of claims 1-6 includes: External scene input module; used to receive scene information input by the user, and to use the input scene information to establish digital demonstration scene information, and input the digital demonstration scene information to the echo parameter calculation module; The signal processing module utilizes an FPGA unit, an A / D unit, and a D / A unit to process and store signals, generating analog echo signals. The FPGA unit includes a processor and a memory for signal calculation, processing, and storage. The A / D unit converts the wireless signal from analog to digital. The D / A unit converts the wireless signal from digital to analog. Echo parameter processing module; used to calculate echo signal parameter information based on digital demonstration scene information and wireless signals; A physical radar module; the physical radar module represents a radar in a physical sense and is used to transmit radar wireless signals and receive echo signals.

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