CN117269907A - DRFM-based high-precision continuous wave radar target simulation method and device - Google Patents
DRFM-based high-precision continuous wave radar target simulation method and device Download PDFInfo
- Publication number
- CN117269907A CN117269907A CN202311229997.3A CN202311229997A CN117269907A CN 117269907 A CN117269907 A CN 117269907A CN 202311229997 A CN202311229997 A CN 202311229997A CN 117269907 A CN117269907 A CN 117269907A
- Authority
- CN
- China
- Prior art keywords
- radar
- signal
- frequency
- target
- module
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000004088 simulation Methods 0.000 title claims abstract description 124
- 238000000034 method Methods 0.000 title claims abstract description 32
- 238000006243 chemical reaction Methods 0.000 claims description 81
- 238000012545 processing Methods 0.000 claims description 47
- 238000005259 measurement Methods 0.000 claims description 15
- 238000005070 sampling Methods 0.000 claims description 15
- 230000003321 amplification Effects 0.000 claims description 9
- 238000003199 nucleic acid amplification method Methods 0.000 claims description 9
- 238000004364 calculation method Methods 0.000 claims description 3
- 230000010355 oscillation Effects 0.000 claims description 3
- 230000005855 radiation Effects 0.000 claims description 3
- 230000007547 defect Effects 0.000 abstract description 3
- 238000001514 detection method Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 5
- 230000005540 biological transmission Effects 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000002592 echocardiography Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/40—Means for monitoring or calibrating
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A90/00—Technologies having an indirect contribution to adaptation to climate change
- Y02A90/10—Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
The invention relates to continuous wave radar target simulation, in particular to a DRFM-based high-precision continuous wave radar target simulation method and equipment, and the channel time delay of target simulation equipment is calibrated; aligning target simulation equipment with a main lobe of the radar to be measured, and measuring an initial distance between the target simulation equipment and the radar to be measured; controlling target simulation equipment and a radar to be tested to enter a working state, receiving radar signals by the target simulation equipment, and measuring the frequency modulation slope of the radar to be tested; calculating the actual frequency shift of the target analog signal based on the channel delay of the target analog device and the frequency modulation slope of the radar to be detected; performing frequency shift and power modulation on the received radar signal based on the actual frequency shift amount of the target analog signal to generate an intermediate frequency digital analog signal; the technical scheme provided by the invention can effectively overcome the defects that the waveform parameters of the radar to be detected need to be accurately known when the target simulation is carried out and the error of the target simulation distance is larger due to the channel time delay and the initial distance in the prior art.
Description
Technical Field
The invention relates to continuous wave radar target simulation, in particular to a DRFM-based high-precision continuous wave radar target simulation method and equipment.
Background
Although continuous wave radar is simple in design and relatively limited in detection distance, continuous wave radar is paid attention again along with the requirements of low interception and low-speed small target detection. The continuous wave radar has low transmitting power and natural low interception advantage, and the low interception is an important precondition of anti-interference, and the typical low interception radar in foreign countries adopts a continuous wave system. On the other hand, the continuous wave radar adopts a large-time-width signal, is more beneficial to modulating broadband waveforms, and realizes low signal interception.
The difficulty of low-speed small target detection comes from two aspects: the radar scattering cross section area of the target is small, which is not beneficial to radar detection; the target is shielded by ground clutter and is not easy to distinguish. The continuous wave radar has the advantages in two aspects, firstly, under the condition of the same power, the accumulation time of the irradiation target of the continuous wave radar is longer, the larger signal-to-noise ratio gain is obtained, meanwhile, the time-free width of the continuous wave radar transmitting signal is limited, and the Doppler spectrum resolution is high; secondly, in a severe clutter environment, the low-speed small target ground detection can be realized by utilizing the Doppler high-resolution capability and combining a super clutter detection technology.
The continuous wave radar target simulation system can simulate various stationary and moving target echoes according to the reflection characteristics of targets based on the working principle of the continuous wave radar, and is core equipment for debugging and performance testing of the whole continuous wave radar. In the prior art, the target simulation of the continuous wave radar is mainly realized based on a DDS scheme, such as the invention patent application of a continuous wave radar target simulator with the application publication number of CN 112698286A and the invention patent application of a civil continuous wave radar target simulation method with the application publication number of CN 111781569A, which are all implemented by adopting a digital frequency synthesis scheme, the simulation method needs to accurately know the waveform parameters of the radar to be detected, so that the radar parameters need to be recorded in detail before the target simulation is implemented in practical application. Meanwhile, due to errors and noise characteristics of digital frequency synthesis, analog errors are inevitably introduced, and the influence of channel delay of a target simulator and the initial distance between the target simulator and a radar to be measured on the target analog distance is not considered in the scheme. Because the inherent channel delay of the target simulator and the initial distance between the target simulator and the radar to be tested exist, the channel delay and the initial distance can be overlapped into the simulated echo in a delay mode during target simulation, and a large error exists between the target simulation distance and the actual target distance.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention provides a DRFM-based high-precision continuous wave radar target simulation method and device, which can effectively overcome the defects that the waveform parameters of the radar to be tested need to be accurately known when target simulation is carried out and the target simulation distance error is larger due to channel time delay and initial distance in the prior art.
In order to achieve the above purpose, the invention is realized by the following technical scheme:
a DRFM-based high-precision continuous wave radar target simulation method comprises the following steps:
s1, calibrating channel time delay of target simulation equipment;
s2, aligning the target simulation equipment with a main lobe of the radar to be measured, and measuring the initial distance between the target simulation equipment and the radar to be measured;
s3, controlling the target simulation equipment and the radar to be tested to enter a working state, receiving radar signals by the target simulation equipment, and measuring the frequency modulation slope of the radar to be tested;
s4, calculating the actual frequency shift quantity of the target analog signal based on the channel time delay of the target analog device and the frequency modulation slope of the radar to be detected;
s5, performing frequency shift and power modulation on the received radar signal based on the actual frequency shift quantity of the target analog signal to generate an intermediate frequency digital analog signal;
s6, the target simulation equipment performs signal processing on the intermediate frequency digital simulation signals to generate final target simulation signals, and transmits the final target simulation signals to the radar to be detected.
Preferably, the identifying the channel delay of the target simulation device in S1 includes:
s11, connecting an input port and an output port of target simulation equipment through a double female connector;
s12, the display control equipment sends a control instruction to a digital processing module of the target analog equipment, the digital processing module generates a point frequency continuous wave signal, andthe microwave module is output to the target simulation equipment through the DA conversion module, and timing t is started at the same time 0 ；
S13, after passing through the up-conversion module, the amplitude control module and the amplifying module, the point frequency continuous wave signal enters the receiving front end through the double-female connector and returns to the digital processing module through the down-conversion module;
s14, after the digital processing module digitizes the point frequency continuous wave signal through the AD conversion module, the arrival time t is measured s ；
S15, based on initial time t 0 And time of arrival t s Calculating channel time delay t of target simulation equipment d ：
。
Preferably, the measuring the initial distance between the target simulation device and the radar to be measured in S2 includes:
s21, transmitting radar signals by the radar to be detected;
s22, setting the analog frequency shift quantity of the target analog signal to be 0 on a display control interface of display control equipment, and forwarding the radar signal received by the target analog equipment to a radar to be detected;
s23, according to the continuous wave working principle, the distance measured by the radar to be measured is the initial distance R c 。
Preferably, the target simulation device in S3 receives the radar signal and measures a frequency modulation slope of the radar to be measured, including:
s31, the target simulation equipment receives radar signals and sends the radar signals into the microwave module;
s32, the microwave module amplifies radar signals through the receiving front end and the down-conversion module, and sends the radar signals to the digital processing module after down-conversion;
s33, after the digital processing module digitizes the radar signal through the AD conversion module, the frequency modulation slope k of the radar to be measured is obtained through parameter measurement.
Preferably, the obtaining the frequency modulation slope k of the radar to be measured through parameter measurement in S33 includes:
s331, performing frequency domain channelizing on the radar signal after the digitalization, and converting a complex signal output by the frequency domain channelizing into amplitude data and phase data;
s332, confirming the existence of a signal by using the amplitude data, and detecting the peak value of the signal;
s333, after the signal is confirmed, the phase data is utilized to carry out first order difference on the phase according to the following formula, and the frequency of the signal is obtained:
，
wherein,for the signal frequency obtained by the first order difference, < >>For the phase of the nth sample point, +.>For the phase of the n-1 th sampling point, T s Is the sampling period;
s334, performing curve fitting based on the multi-channel frequency measurement data;
s335, after multipoint sampling is carried out on the fitting curve, the frequency modulation slope k of the radar to be detected is obtained through calculation according to the following formula:
，
wherein x is i 、y i For fitting the abscissa and ordinate of any point on the curve, m is the number of sampling points used in calculating the chirp rate k.
Preferably, in S4, calculating the actual frequency shift amount of the target analog signal based on the channel delay of the target analog device and the frequency modulation slope of the radar to be measured includes:
s41, channel time delay t based on target simulation equipment d The channel delay t is calculated according to the following formula d Induced distance simulation error R te ：
，
S42, based on the measured initial distance R c And a distance simulation error R te The actual simulation distance R is calculated according to the following equation:
，
wherein R is set Setting an analog distance;
s43, calculating the actual frequency shift of the target analog signal based on the frequency modulation slope k and the actual analog distance R of the radar to be detected：
，
Wherein c is the speed of light.
Preferably, the step S6 of generating a final target analog signal by the target analog device after performing signal processing on the intermediate digital analog signal, and transmitting the final target analog signal to the radar to be detected includes:
s61, the digital processing module performs digital-to-analog conversion on the intermediate frequency digital analog signals through the DA conversion module to obtain intermediate frequency analog signals, and sends the intermediate frequency analog signals to the microwave module;
s62, the microwave module performs up-conversion, attenuation control and amplification on the intermediate frequency analog signal through the up-conversion module, the amplitude control module and the amplification module to obtain a final target analog signal;
s63, the target simulation equipment transmits a final target simulation signal to the radar to be tested through the transmitting antenna.
A DRFM-based high-precision continuous wave radar target simulation device comprises an antenna, a host and display control equipment, wherein the host comprises a microwave module and a digital processing module, and the microwave module comprises a receiving front end, a down-conversion module, an up-conversion module, an amplitude control module, an amplifying module and a frequency source;
the antenna comprises a receiving antenna and a transmitting antenna which are identical, wherein the receiving antenna is used for receiving the space electromagnetic wave, and the transmitting antenna is used for radiating the electromagnetic wave to the space;
the receiving front end receives the radio frequency signal transmitted by the receiving antenna, performs low noise amplification and then sends the radio frequency signal to the down-conversion module;
the down-conversion module is used for receiving the radio frequency signal transmitted by the front end, obtaining an intermediate frequency signal after down-conversion, and sending the intermediate frequency signal to the digital processing module;
the up-conversion module receives the intermediate frequency analog signal sent by the digital processing module, up-converts the intermediate frequency analog signal to obtain a radio frequency signal, and sends the radio frequency signal to the amplitude control module;
the amplitude control module receives the amplitude control signal of the digital processing module and carries out attenuation control on the radio frequency signal sent by the up-conversion module;
the amplifying module is used for receiving the radio frequency signals sent by the amplitude control module, amplifying the power of the radio frequency signals and sending the radio frequency signals to the transmitting antenna to aim at target radiation;
the frequency source provides local oscillation signals for the down-conversion module and the up-conversion module, and provides a reference clock and a sampling clock for the digital processing module;
the digital processing module is used for finishing the digitization of the received signal, digital frequency storage, parameter measurement, generation of an intermediate frequency digital analog signal, generation of an amplitude control signal and digital-to-analog conversion.
Preferably, the digital processing module comprises a control chip, an FPGA, an AD conversion module and a DA conversion module, wherein the control chip is connected between the FPGA and the display control device, the AD conversion module is connected between the down-conversion module and the FPGA, and the DA conversion module is connected between the up-conversion module and the FPGA.
Compared with the prior art, the DRFM-based high-precision continuous wave radar target simulation method and device provided by the invention have the following beneficial effects:
1) The method has the advantages that the target simulation is carried out by combining the digital frequency storage with the frequency shift transmission, the digital frequency shift transmission is carried out by the DRFM, the waveform parameters of the radar to be detected are not required to be known, meanwhile, the frequency shift transmission is adopted, the target simulation precision can be ensured, and the limitation of delay transmission is broken;
2) The method comprises the steps of calibrating the channel time delay of the target simulation equipment, calculating the actual frequency shift quantity of the target simulation signal based on the channel time delay of the target simulation equipment and the frequency modulation slope of the radar to be tested, and effectively eliminating the influence of the channel time delay of the target simulation equipment on the target simulation distance, so that the target simulation precision is greatly improved;
3) By measuring the initial distance between the target simulation device and the radar to be tested and calculating the actual simulation distance based on the initial distance and the distance simulation error, the influence of the initial distance between the target simulation device and the radar to be tested on the target simulation distance can be effectively eliminated, and the target simulation precision is greatly improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It is evident that the drawings in the following description are only some embodiments of the present invention and that other drawings may be obtained from these drawings without inventive effort for a person of ordinary skill in the art.
FIG. 1 is a schematic flow chart of the present invention;
FIG. 2 is a schematic diagram of curve fitting based on multi-channel frequency measurement data in the present invention;
FIG. 3 is a schematic diagram of radar signals of a multi-channel measurement continuous wave radar according to the present invention;
FIG. 4 is a hardware diagram of the apparatus of the present invention;
FIG. 5 is a detailed device hardware diagram of FIG. 4 in accordance with the present invention;
fig. 6 is a device hardware diagram of the channel delay for a target simulation device identified in the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It will be apparent that the described embodiments are some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
As shown in FIG. 1, the method for simulating the target of the high-precision continuous wave radar based on the DRFM comprises the following steps of S1, calibrating the channel time delay of target simulation equipment:
s11, connecting an input port and an output port of the target simulation equipment through a double female connector (shown in fig. 6);
s12, the display control equipment sends a control instruction to a digital processing module of the target analog equipment, the digital processing module generates a point frequency continuous wave signal, the point frequency continuous wave signal is output to a microwave module of the target analog equipment through a DA conversion module, and timing t is started at the same time 0 ；
S13, after passing through the up-conversion module, the amplitude control module and the amplifying module, the point frequency continuous wave signal enters the receiving front end through the double-female connector and returns to the digital processing module through the down-conversion module;
s14, after the digital processing module digitizes the point frequency continuous wave signal through the AD conversion module, the arrival time t is measured s ；
S15, based on initial time t 0 And time of arrival t s Calculating channel time delay t of target simulation equipment d ：
。
S2, aligning the target simulation equipment with a main lobe of the radar to be measured, and measuring the initial distance between the target simulation equipment and the radar to be measured.
Specifically, measuring an initial distance between the target simulation device and the radar to be measured includes:
s21, transmitting radar signals by the radar to be detected;
s22, setting the analog frequency shift quantity of the target analog signal to be 0 on a display control interface of display control equipment, and forwarding the radar signal received by the target analog equipment to a radar to be detected;
s23, according to the continuous wave working principle, the test is carried outThe distance measured by the radar is the initial distance R c 。
S3, controlling the target simulation equipment and the radar to be tested to enter a working state, receiving radar signals by the target simulation equipment, and measuring the frequency modulation slope of the radar to be tested.
Specifically, the target simulation device receives radar signals and measures a frequency modulation slope of a radar to be measured, and the target simulation device comprises:
s31, the target simulation equipment receives radar signals and sends the radar signals into the microwave module;
s32, the microwave module amplifies radar signals through the receiving front end and the down-conversion module, and sends the radar signals to the digital processing module after down-conversion;
s33, after the digital processing module digitizes the radar signal through the AD conversion module, the frequency modulation slope k of the radar to be measured is obtained through parameter measurement.
And S33, obtaining the frequency modulation slope k of the radar to be measured through parameter measurement, wherein the frequency modulation slope k comprises the following components:
s331, performing frequency domain channelizing on the radar signal after the digitalization, and converting a complex signal output by the frequency domain channelizing into amplitude data and phase data;
s332, confirming the existence of a signal by using the amplitude data, and detecting the peak value of the signal;
s333, after the signal is confirmed, the phase data is utilized to carry out first order difference on the phase according to the following formula, and the frequency of the signal is obtained:
，
wherein,for the signal frequency obtained by the first order difference, < >>For the phase of the nth sample point, +.>For the phase of the n-1 th sampling point, T s Is the sampling period;
s334, performing curve fitting based on the multi-channel frequency measurement data;
s335, after multipoint sampling is carried out on the fitting curve, the frequency modulation slope k of the radar to be detected is obtained through calculation according to the following formula:
，
wherein x is i 、y i For fitting the abscissa and ordinate of any point on the curve, m is the number of sampling points used in calculating the chirp rate k.
S4, calculating the actual frequency shift amount of the target analog signal based on the channel delay of the target analog device and the frequency modulation slope of the radar to be detected, wherein the method specifically comprises the following steps:
s41, channel time delay t based on target simulation equipment d The channel delay t is calculated according to the following formula d Induced distance simulation error R te ：
，
S42, based on the measured initial distance R c And a distance simulation error R te The actual simulation distance R is calculated according to the following equation:
，
wherein R is set Setting an analog distance;
s43, calculating the actual frequency shift of the target analog signal based on the frequency modulation slope k and the actual analog distance R of the radar to be detected：
，
Wherein c is the speed of light.
S5, performing frequency shift and power modulation on the received radar signal based on the actual frequency shift amount of the target analog signal, and generating an intermediate frequency digital analog signal.
The fundamental principle of the continuous wave radar detection target is to solve the echo delay by combining the frequency difference obtained by measurement with the known frequency modulation slope. Therefore, in the target simulation, the distance simulation may employ a time delay method or a frequency shift method, and the velocity simulation may employ a method of increasing the doppler shift.
The distance simulation precision of the time delay method depends on the time delay precision, and the time delay precision can only reach the inverse of the clock frequency (namely one CLK) at the highest, so the distance simulation precision of the time delay method is not high generally, and the distance simulation is carried out by adopting the frequency shift method.
S6, the target simulation equipment generates a final target simulation signal after performing signal processing on the intermediate frequency digital simulation signal, and transmits the final target simulation signal to the radar to be detected, and the method specifically comprises the following steps:
s61, the digital processing module performs digital-to-analog conversion on the intermediate frequency digital analog signals through the DA conversion module to obtain intermediate frequency analog signals, and sends the intermediate frequency analog signals to the microwave module;
s62, the microwave module performs up-conversion, attenuation control and amplification on the intermediate frequency analog signal through the up-conversion module, the amplitude control module and the amplification module to obtain a final target analog signal;
s63, the target simulation equipment transmits a final target simulation signal to the radar to be tested through the transmitting antenna.
In the technical scheme, as shown in fig. 4 and 5, a high-precision continuous wave radar target simulation device based on DRFM is also disclosed, which comprises an antenna, a host and a display control device, wherein the host comprises a microwave module and a digital processing module, and the microwave module comprises a receiving front end, a down-conversion module, an up-conversion module, an amplitude control module, an amplifying module and a frequency source;
the antenna comprises a receiving antenna and a transmitting antenna which are identical, wherein the receiving antenna is used for receiving the space electromagnetic wave, and the transmitting antenna is used for radiating the electromagnetic wave to the space;
the receiving front end receives the radio frequency signal transmitted by the receiving antenna, performs low noise amplification and then sends the radio frequency signal to the down-conversion module;
the down-conversion module is used for receiving the radio frequency signal transmitted by the front end, obtaining an intermediate frequency signal after down-conversion, and sending the intermediate frequency signal to the digital processing module;
the up-conversion module receives the intermediate frequency analog signal sent by the digital processing module, up-converts the intermediate frequency analog signal to obtain a radio frequency signal, and sends the radio frequency signal to the amplitude control module;
the amplitude control module receives the amplitude control signal of the digital processing module and carries out attenuation control on the radio frequency signal sent by the up-conversion module;
the amplifying module is used for receiving the radio frequency signals sent by the amplitude control module, amplifying the power of the radio frequency signals and sending the radio frequency signals to the transmitting antenna to aim at target radiation;
the frequency source provides local oscillation signals for the down-conversion module and the up-conversion module, and provides a reference clock and a sampling clock for the digital processing module;
the digital processing module is used for finishing the digitization of the received signal, digital frequency storage, parameter measurement, generation of an intermediate frequency digital analog signal, generation of an amplitude control signal and digital-to-analog conversion.
Specifically, the digital processing module comprises a control chip, an FPGA, an AD conversion module and a DA conversion module, wherein the control chip is connected between the FPGA and the display control equipment, the AD conversion module is connected between the down-conversion module and the FPGA, and the DA conversion module is connected between the up-conversion module and the FPGA.
The above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims (9)
1. The DRFM-based high-precision continuous wave radar target simulation method is characterized by comprising the following steps of: the method comprises the following steps:
s1, calibrating channel time delay of target simulation equipment;
s2, aligning the target simulation equipment with a main lobe of the radar to be measured, and measuring the initial distance between the target simulation equipment and the radar to be measured;
s3, controlling the target simulation equipment and the radar to be tested to enter a working state, receiving radar signals by the target simulation equipment, and measuring the frequency modulation slope of the radar to be tested;
s4, calculating the actual frequency shift quantity of the target analog signal based on the channel time delay of the target analog device and the frequency modulation slope of the radar to be detected;
s5, performing frequency shift and power modulation on the received radar signal based on the actual frequency shift quantity of the target analog signal to generate an intermediate frequency digital analog signal;
s6, the target simulation equipment performs signal processing on the intermediate frequency digital simulation signals to generate final target simulation signals, and transmits the final target simulation signals to the radar to be detected.
2. The DRFM-based high precision continuous wave radar target simulation method of claim 1, wherein: s1, identifying channel delay of target simulation equipment, comprising:
s11, connecting an input port and an output port of target simulation equipment through a double female connector;
s12, the display control equipment sends a control instruction to a digital processing module of the target analog equipment, the digital processing module generates a point frequency continuous wave signal, the point frequency continuous wave signal is output to a microwave module of the target analog equipment through a DA conversion module, and timing t is started at the same time 0 ；
S13, after passing through the up-conversion module, the amplitude control module and the amplifying module, the point frequency continuous wave signal enters the receiving front end through the double-female connector and returns to the digital processing module through the down-conversion module;
s14, after the digital processing module digitizes the point frequency continuous wave signal through the AD conversion module, the arrival time t is measured s ；
S15, based on initial time t 0 And time of arrival t s Calculating channel time delay t of target simulation equipment d ：
。
3. The DRFM-based high precision continuous wave radar target simulation method of claim 2, wherein: s2, measuring an initial distance between target simulation equipment and a radar to be measured, wherein the initial distance comprises the following steps:
s21, transmitting radar signals by the radar to be detected;
s22, setting the analog frequency shift quantity of the target analog signal to be 0 on a display control interface of display control equipment, and forwarding the radar signal received by the target analog equipment to a radar to be detected;
s23, according to the continuous wave working principle, the distance measured by the radar to be measured is the initial distance R c 。
4. The DRFM-based high precision continuous wave radar target simulation method of claim 3, wherein: s3, the target simulation equipment receives radar signals and measures the frequency modulation slope of the radar to be measured, and the method comprises the following steps:
s31, the target simulation equipment receives radar signals and sends the radar signals into the microwave module;
s32, the microwave module amplifies radar signals through the receiving front end and the down-conversion module, and sends the radar signals to the digital processing module after down-conversion;
s33, after the digital processing module digitizes the radar signal through the AD conversion module, the frequency modulation slope k of the radar to be measured is obtained through parameter measurement.
5. The DRFM-based high accuracy continuous wave radar target simulation method of claim 4, wherein: and S33, obtaining the frequency modulation slope k of the radar to be measured through parameter measurement, wherein the frequency modulation slope k comprises the following components:
s331, performing frequency domain channelizing on the radar signal after the digitalization, and converting a complex signal output by the frequency domain channelizing into amplitude data and phase data;
s332, confirming the existence of a signal by using the amplitude data, and detecting the peak value of the signal;
s333, after the signal is confirmed, the phase data is utilized to carry out first order difference on the phase according to the following formula, and the frequency of the signal is obtained:
，
wherein,for the signal frequency obtained by the first order difference, < >>For the phase of the nth sample point, +.>For the phase of the n-1 th sampling point, T s Is the sampling period;
s334, performing curve fitting based on the multi-channel frequency measurement data;
s335, after multipoint sampling is carried out on the fitting curve, the frequency modulation slope k of the radar to be detected is obtained through calculation according to the following formula:
，
wherein x is i 、y i For fitting the abscissa and ordinate of any point on the curve, m is the number of sampling points used in calculating the chirp rate k.
6. The DRFM-based high accuracy continuous wave radar target simulation method of claim 5, wherein: s4, calculating the actual frequency shift of the target analog signal based on the channel delay of the target analog device and the frequency modulation slope of the radar to be detected, wherein the method comprises the following steps:
s41, channel time delay t based on target simulation equipment d The channel delay t is calculated according to the following formula d Induced distance simulation error R te ：
，
S42, based on the measured initial distance R c And a distance simulation error R te The actual simulation distance R is calculated according to the following equation:
，
wherein R is set Setting an analog distance;
s43, calculating the actual frequency shift of the target analog signal based on the frequency modulation slope k and the actual analog distance R of the radar to be detected：
，
Wherein c is the speed of light.
7. The DRFM-based high accuracy continuous wave radar target simulation method of claim 6, wherein: s6, the target simulation equipment generates a final target simulation signal after performing signal processing on the intermediate frequency digital simulation signal, and transmits the final target simulation signal to the radar to be detected, and the method comprises the following steps:
s61, the digital processing module performs digital-to-analog conversion on the intermediate frequency digital analog signals through the DA conversion module to obtain intermediate frequency analog signals, and sends the intermediate frequency analog signals to the microwave module;
s62, the microwave module performs up-conversion, attenuation control and amplification on the intermediate frequency analog signal through the up-conversion module, the amplitude control module and the amplification module to obtain a final target analog signal;
s63, the target simulation equipment transmits a final target simulation signal to the radar to be tested through the transmitting antenna.
8. An apparatus for performing the DRFM-based high precision continuous wave radar target simulation method of claim 7, characterized by: the system comprises an antenna, a host and display control equipment, wherein the host comprises a microwave module and a digital processing module, and the microwave module comprises a receiving front end, a down-conversion module, an up-conversion module, an amplitude control module, an amplifying module and a frequency source;
the antenna comprises a receiving antenna and a transmitting antenna which are identical, wherein the receiving antenna is used for receiving the space electromagnetic wave, and the transmitting antenna is used for radiating the electromagnetic wave to the space;
the receiving front end receives the radio frequency signal transmitted by the receiving antenna, performs low noise amplification and then sends the radio frequency signal to the down-conversion module;
the down-conversion module is used for receiving the radio frequency signal transmitted by the front end, obtaining an intermediate frequency signal after down-conversion, and sending the intermediate frequency signal to the digital processing module;
the up-conversion module receives the intermediate frequency analog signal sent by the digital processing module, up-converts the intermediate frequency analog signal to obtain a radio frequency signal, and sends the radio frequency signal to the amplitude control module;
the amplitude control module receives the amplitude control signal of the digital processing module and carries out attenuation control on the radio frequency signal sent by the up-conversion module;
the amplifying module is used for receiving the radio frequency signals sent by the amplitude control module, amplifying the power of the radio frequency signals and sending the radio frequency signals to the transmitting antenna to aim at target radiation;
the frequency source provides local oscillation signals for the down-conversion module and the up-conversion module, and provides a reference clock and a sampling clock for the digital processing module;
the digital processing module is used for finishing the digitization of the received signal, digital frequency storage, parameter measurement, generation of an intermediate frequency digital analog signal, generation of an amplitude control signal and digital-to-analog conversion.
9. The apparatus according to claim 8, wherein: the digital processing module comprises a control chip, an FPGA, an AD conversion module and a DA conversion module, wherein the control chip is connected between the FPGA and the display control equipment, the AD conversion module is connected between the down-conversion module and the FPGA, and the DA conversion module is connected between the up-conversion module and the FPGA.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311229997.3A CN117269907B (en) | 2023-09-22 | 2023-09-22 | DRFM-based high-precision continuous wave radar target simulation method and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311229997.3A CN117269907B (en) | 2023-09-22 | 2023-09-22 | DRFM-based high-precision continuous wave radar target simulation method and device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN117269907A true CN117269907A (en) | 2023-12-22 |
| CN117269907B CN117269907B (en) | 2024-02-13 |
Family
ID=89220891
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311229997.3A Active CN117269907B (en) | 2023-09-22 | 2023-09-22 | DRFM-based high-precision continuous wave radar target simulation method and device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117269907B (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104965197A (en) * | 2015-06-30 | 2015-10-07 | 南京理工大学 | FPGA-based radar echo signal simulator |
| JP2017166940A (en) * | 2016-03-16 | 2017-09-21 | 日本無線株式会社 | Target distance simulation device |
| CN112068091A (en) * | 2020-07-20 | 2020-12-11 | 杭州永谐科技有限公司 | Method for performing radar target mode by using signal source |
| CN112748411A (en) * | 2020-12-25 | 2021-05-04 | 北京理工大学 | Close-range target echo simulation method and system for sawtooth radar |
| CN113238196A (en) * | 2021-05-22 | 2021-08-10 | 中国船舶重工集团公司第七二三研究所 | Radar echo simulation method based on radio frequency scene storage |
| US20220107389A1 (en) * | 2020-10-06 | 2022-04-07 | Rohde & Schwarz Gmbh & Co. Kg | Radar target simulator with continuous distance emulation and corresponding simulation method |
| CN114859308A (en) * | 2022-07-11 | 2022-08-05 | 陕西昱琛航空设备股份有限公司 | Radar target simulator and calibration method thereof |
| KR20220139715A (en) * | 2021-04-08 | 2022-10-17 | 엘아이지넥스원 주식회사 | Simulated target signal generating apparatus and radar test system having the same |
-
2023
- 2023-09-22 CN CN202311229997.3A patent/CN117269907B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104965197A (en) * | 2015-06-30 | 2015-10-07 | 南京理工大学 | FPGA-based radar echo signal simulator |
| JP2017166940A (en) * | 2016-03-16 | 2017-09-21 | 日本無線株式会社 | Target distance simulation device |
| CN112068091A (en) * | 2020-07-20 | 2020-12-11 | 杭州永谐科技有限公司 | Method for performing radar target mode by using signal source |
| US20220107389A1 (en) * | 2020-10-06 | 2022-04-07 | Rohde & Schwarz Gmbh & Co. Kg | Radar target simulator with continuous distance emulation and corresponding simulation method |
| CN112748411A (en) * | 2020-12-25 | 2021-05-04 | 北京理工大学 | Close-range target echo simulation method and system for sawtooth radar |
| KR20220139715A (en) * | 2021-04-08 | 2022-10-17 | 엘아이지넥스원 주식회사 | Simulated target signal generating apparatus and radar test system having the same |
| CN113238196A (en) * | 2021-05-22 | 2021-08-10 | 中国船舶重工集团公司第七二三研究所 | Radar echo simulation method based on radio frequency scene storage |
| CN114859308A (en) * | 2022-07-11 | 2022-08-05 | 陕西昱琛航空设备股份有限公司 | Radar target simulator and calibration method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN117269907B (en) | 2024-02-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107728127B (en) | Radar simulation test system | |
| CN111183741B (en) | Broadband radar target simulation method and system | |
| CN109239684B (en) | Radar target echo simulation system based on electromagnetic scattering model and simulation method thereof | |
| US7554486B2 (en) | System and method for dual polarization radar with automatic built-in test equipment and calibration | |
| EP2290392B1 (en) | Enhanced impulse response measurement of an FM radar transmitter pulse | |
| CN106353748B (en) | Signal processing apparatus and method for fmcw radar range-measurement system | |
| US7592948B2 (en) | System and method for dual polarization radar with automatic built-in test equipment and calibration | |
| CN105158763A (en) | Meteorological radar system based on continuous wave system and control method | |
| CN104635218B (en) | Millimeter wave radiometer semi-physical simulation system, signal generating method and linearity testing method | |
| CN104166126A (en) | Echo signal simulation method used for continuous wave radar | |
| US8325084B2 (en) | System for calibration of dual polarization radar with built-in test couplers | |
| CN105204023A (en) | Echo signal processing method and device of weather radar system based on continuous wave system | |
| CN113009436B (en) | Spatial angular position parameter calibration method | |
| CN104931797A (en) | Method for measuring dielectric constant of lossy medium based on wave-transparent mechanism | |
| CN101464514B (en) | Calibration method and calibration processor for step frequency radar system | |
| CN110850380A (en) | Method for realizing weather radar digital calibration unit | |
| CN103954937B (en) | A kind of wide region High-precision Microwave range radar design method | |
| CN113608183B (en) | Hypersonic broadband radio frequency target simulation system | |
| CN102798769B (en) | Narrow-band antenna test method based on return loss compensation | |
| CA2711460C (en) | An improved system and method for dual polarization radar with automatic built-in test equipment and calibration | |
| CN117269907B (en) | DRFM-based high-precision continuous wave radar target simulation method and device | |
| CN111856425A (en) | Non-rigid body target electromagnetic characteristic simulation test method | |
| CN112684421A (en) | Coherent calibration source system for linear frequency modulation continuous wave radar | |
| CN112859021B (en) | Method and system for testing full-link dynamic range and sensitivity of phased array radar | |
| CN114325084B (en) | High-power pulse measuring device and measuring method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |