CN115356691B - Multi-target distance speed coupling solving method based on single-group SFCW radar signals - Google Patents
Multi-target distance speed coupling solving method based on single-group SFCW radar signals Download PDFInfo
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- 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
- G01S7/28—Details of pulse systems
- G01S7/285—Receivers
- G01S7/288—Coherent receivers
- G01S7/2883—Coherent receivers using FFT processing
-
- 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
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
- G01S13/06—Systems determining position data of a target
- G01S13/08—Systems for measuring distance only
- G01S13/10—Systems for measuring distance only using transmission of interrupted, pulse modulated waves
- G01S13/12—Systems for measuring distance only using transmission of interrupted, pulse modulated waves wherein the pulse-recurrence frequency is varied to provide a desired time relationship between the transmission of a pulse and the receipt of the echo of a preceding pulse
-
- 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
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
- G01S13/50—Systems of measurement based on relative movement of target
- G01S13/58—Velocity or trajectory determination systems; Sense-of-movement determination systems
- G01S13/581—Velocity or trajectory determination systems; Sense-of-movement determination systems using transmission of interrupted pulse modulated waves and based upon the Doppler effect resulting from movement of targets
- G01S13/582—Velocity or trajectory determination systems; Sense-of-movement determination systems using transmission of interrupted pulse modulated waves and based upon the Doppler effect resulting from movement of targets adapted for simultaneous range and velocity measurements
-
- 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
- G01S7/28—Details of pulse systems
- G01S7/285—Receivers
- G01S7/292—Extracting wanted echo-signals
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- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
The invention discloses a solution multi-target distance speed coupling method based on single-group SFCW radar signals, wherein the first step is to calculate the target position (called as 'speed-containing distance' herein) with distance speed coupling through an IFFT method; the second step is to solve the speed of the target at the speed-containing distance based on the phase difference of the sampling points at different moments; and thirdly, obtaining the true distance of the target from the speed band to the speed-containing distance. The invention has the advantages that: 1. the distance and speed coupling problem of the SFCW radar can be solved; 2. target decomposition after overlapping of multiple target IFFT points with different distance speeds can be solved; 3. the SFCW radar data refresh rate can be improved; 4. the method has high popularization value for ADAS millimeter wave radars.
Description
Technical Field
The invention relates to the technical field of radars, in particular to a solution multi-target distance speed coupling method based on a single group of SFCW radar signals.
Background
The step frequency radar signal has wide application in military and civil radars because of the wide bandwidth, good distance and Doppler resolution capability, especially narrower instantaneous bandwidth; in the field of automatic driving ADAS millimeter wave radar, step frequency (MFSK) and Linear Frequency Modulation (LFM) are almost all used.
However, the step frequency signal is sensitive to the moving target, and the target position after the IFFT has distance-Doppler (velocity) coupling, so that corresponding measures are needed to be taken for decoupling in practical application, and the MFSK is the SFCW signal of 2 groups of different initial frequencies, and the distance-velocity coupling problem is solved through the phase relation between 2 groups of corresponding IFFT target points.
The invention provides a decoupling solution for distance velocity based on a set of SFCW signals. By sampling each single-frequency pulse a plurality of times, respectively performing IFFT on a plurality of samples, the phase difference of the sampling points at different moments corresponding to a certain target point of the IFFT is in linear relation with the speed of the target, so that the speed of the target point can be obtained through the phase difference, and the distance speed coupling can be solved.
Disclosure of Invention
The technical problem to be solved by the invention is to overcome the technical defects, and provide a solution multi-target distance speed coupling method based on single-group SFCW radar signals.
In order to solve the technical problems, the technical scheme provided by the invention is as follows: a method for resolving multi-target distance velocity coupling based on a single group of SFCW radar signals, comprising the steps of:
1) The radar continuously transmits N single-frequency signals with the frequency difference delta f;
2) Down-converting the target echo to a baseband at a receiving end and continuously performing A/D sampling;
3) Setting each single-frequency pulse sampling point as M, and setting N stepping pulse sampling points as N multiplied by M (1, 2 … M, M+ … M, …, (N-1) M+ … N multiplied by M);
4) N-point IFFT (M N-point IFFT) is carried out on sampling points (1, M+1, …, (N-1) M+1, … …, M, 2M, … and NM) corresponding to N single frequencies at different moments;
5) A target is arranged at the K point, and the distance speed is coupled;
6) Comparing the phase of K at the initial 1,2 and … M points;
7) Calculating the phase difference of the two points, and calculating the speed of the point;
8) The distance of the point can be obtained by bringing the speed obtained in the step 7) to the IFFT result, and the multi-target distance and speed coupling of a group of SFCW signals is achieved.
2. The method for solving multi-target distance velocity coupling based on single-group SFCW radar signals according to claim 1, wherein a target is present at a distance R, the radial velocity of which is v, and the maximum value of the target is at a K point by CFAR detection after IFFT; since there is a distance velocity coupling at this time, there are:
Wherein R is the distance of the target at the position, and DeltaR is the distance resolution; v is the target speed at the point and Deltav is the speed resolution; selecting two groups of sampling points (i and j) (i is less than j) to analyze the result of IFFT, and if the two groups of sampling points (i and j) can acquire the target echo at K positions, the two groups can satisfy the formula (1)
According to the IFFT correlation theory, the two points of K i、Kj have the same amplitude and different phases, and the phases have the following formulas:
Wherein the method comprises the steps of The phase is the K i、Kj point phase, theta i、θj is the initial phase at the sampling points i and j, and delta is the coefficient related to the K point; obviously, the first term on the right of the formulas (3) and (4) is different, the second term is equal, and/>The phase difference is:
where v is the speed of the target at point K and c is the speed of light; the phase value of the position can be obtained by performing IFFT on the ith and j groups, and the motion velocity v of the target of the position can be obtained by substituting the phase value into the formula (5). And (3) carrying the obtained speed into a formula (2) to obtain a distance R corresponding to the K position, so that the distance speed coupling can be decoupled.
Compared with the prior art, the invention has the advantages that:
1. The distance and speed coupling problem of the SFCW radar can be solved;
2. Target decomposition after overlapping of multiple target IFFT points with different distance speeds can be solved;
3. the SFCW radar data refresh rate can be improved;
4. the method has high popularization value for ADAS millimeter wave radars.
Drawings
Fig. 1 is a time-frequency diagram of a set of SFCW signals.
FIG. 2 is a schematic diagram of two different range target echoes
Detailed Description
Specific embodiments of the present invention will be further described below with reference to the accompanying drawings.
The invention comprises 3 steps, wherein the first step is to calculate the target position (called as 'speed-containing distance' herein) with distance and speed coupling through an IFFT method; the second step is to solve the speed of the target at the speed-containing distance based on the phase difference of the sampling points at different moments; and thirdly, obtaining the true distance of the target from the speed band to the speed-containing distance.
Fig. 1 is a graph showing a time-frequency domain of a typical SFCW radar waveform.
Setting: the initial frequency of the transmitting signal is f0, the pulse width Tp, the frequency difference between adjacent pulses, namely the step frequency value is delta f, and N pulses are continuously transmitted;
down-converting the echo signal into a baseband signal, and then sampling the baseband signal to make sampling points 1, 2, …, # M (sampling of 1 st pulse), M+1, M+2, …, # 2M (sampling of 2 nd pulse), … …, (N-1) M+1, (N-1) M+2, … …, NM (sampling of N th pulse); thus, each pulse has M sampling points, and N stepping pulses have NM sampling points;
Firstly, performing N-point IFFT according to a conventional method, wherein the different points in the technical scheme are to perform a plurality of N-point IFFT, and performing M-time IFFT on the corresponding sampling points at M different times, namely performing IFFT on M N points of 1, M+1, …, (N-1) M+1,2, M+2, …, (N-1) M+2, …, M, 2M, … and NM respectively; these M sets of N-point IFFT are called 1 st, 2 … M sets of sample point IFFT, respectively;
assuming that a target exists at the distance R, the radial speed of the target is v, after IFFT, the target is detected by CFAR, and the maximum value of the target is at the K point; since there is a distance velocity coupling at this time, there are:
Wherein R is the distance of the target at the position, and DeltaR is the distance resolution; v is the target speed at the point and Deltav is the speed resolution; selecting two groups of sampling points (i and j) (i is less than j) to analyze the result of IFFT, and if the two groups of sampling points (i and j) can acquire the target echo at K positions, the two groups can satisfy the formula (1)
According to the IFFT correlation theory, the two points of K i、Kj have the same amplitude and different phases, and the phases have the following formulas:
Wherein the method comprises the steps of The phase is the K i、Kj point phase, theta i、θj is the initial phase at the sampling points i and j, and delta is the coefficient related to the K point; obviously, the first term on the right of the formulas (3) and (4) is different, the second term is equal, and/>The phase difference is:
where v is the speed of the target at point K and c is the speed of light; the phase value of the position can be obtained by performing IFFT on the ith and j groups, and the motion velocity v of the target of the position can be obtained by substituting the phase value into the formula (5). And (3) carrying the obtained speed into a formula (2) to obtain a distance R corresponding to the K position, so that the distance speed coupling can be decoupled.
The technical method of the invention is also characterized in that the method can solve the problem of target decomposition after the overlapping of multiple target IFFT points with different distances and speeds, and the targets with different distance speeds are assumed to exist, the distance speeds are (R 1,v1)、(R2,v2) and (R 1＜R2) respectively, and if the two target IFFT after the IFFT appear at the same point, namely:
Since the phase after the IFFT is affected by the different speeds and echo amplitudes of the two targets, the two targets cannot be resolved according to the existing method, such as the phase difference method of the two groups of IFFT results of the MFSK; in the invention, as each single-frequency pulse is sampled at multiple points, two targets with different distances can be separated in the time domain, so that a time period exists, namely, the sampling point only has a target echo with a smaller distance, and the phenomenon of superposition of the two targets is avoided; the distance and velocity of each target can be solved separately. Specifically as shown in fig. 2:
The middle solid line in the figure represents a transmitting signal, is a single-frequency signal with the time width of T P, and the dotted line at the lower side represents an echo signal of a target 1, and is delayed by the time length of T 1 in time compared with the transmitting signal; the upper dash-dot line represents the echo signal of the target 2, and compared with the transmitted signal, the time delay is T 2; since 1 to M samples are sampled at equal intervals in the time period corresponding to the transmission signal, namely, the time period from 0 to T P, it is obvious that the target position after the IFFT at the sampling moment in the time interval between T 1 and T 2 only contains the target 1 echo, and the target 1 and the target 2 are separated in the time domain in the time period; thus, the distance velocity of target 1 can be solved using the methods described above during time periods T 1 and T 2, and the distance velocity of target 2 can be solved at time interval T 2 and TP since R 1,v1 is known.
The invention and its embodiments have been described above with no limitation, and only some, but not all embodiments of the invention are shown in the detailed description, with the true construction not being limited thereto. In summary, if one of ordinary skill in the art is informed by this disclosure, a structural manner and an embodiment similar to the technical solution should not be creatively devised without departing from the gist of the present invention.
Claims (1)
1. A method for resolving multi-target distance velocity coupling based on a single group of SFCW radar signals, comprising the steps of:
1) The radar continuously transmits N single-frequency signals with the frequency difference delta f;
2) Down-converting the target echo to a baseband at a receiving end and continuously performing A/D sampling;
3) Setting each single-frequency pulse sampling point as M, and setting N stepping pulse sampling points as N multiplied by M, namely 1,2 … M, M+ … M and …, (N-1) M+ … N multiplied by M;
4) N-point IFFT is carried out on N sampling points 1, M+1, …, (N-1) M+1, … …, M, 2M, … and NM corresponding to N single frequencies at different moments, namely M N-point IFFT;
5) A target is arranged at the K point, and the distance speed is coupled;
6) Comparing the phase of K at the initial 1,2 and … M points;
7) Calculating the phase difference of the two points, and obtaining the target speed of the point;
8) The distance of the point can be obtained by bringing the target speed obtained in the step 7) to the IFFT result, so that the coupling of a group of SFCW signals for solving the multi-target distance and speed is realized;
A target exists at the distance R, the target speed is v, after IFFT, CFAR detection is carried out, and the maximum value of the target is at the K point; since there is a distance velocity coupling at this time, there are:
Wherein R is the distance of the target at the position, and DeltaR is the distance resolution; v is the target speed at the point and Deltav is the speed resolution; selecting two groups of sampling points (i and j) to perform IFFT result analysis, wherein i is less than j, and if the two groups of sampling points (i and j) can acquire target echoes at K positions, the two groups can satisfy the formula (1)
According to the IFFT correlation theory, the two points of K i、Kj have the same amplitude and different phases, and the phases have the following formulas:
Wherein the method comprises the steps of The phase is the K i、Kj point phase, theta i、θj is the initial phase at the sampling points i and j, and delta is the coefficient related to the K point; obviously, the first term on the right of the formulas (3) and (4) is different, the second term is equal, and/>The phase difference is:
Wherein v is the speed of the target at the K point, c is the speed of light, f0 is the starting frequency of the transmitted signal, and T P is the pulse width; the phase value of the position can be obtained by performing IFFT on the ith and jth groups, the target speed v of the target of the position can be obtained by substituting the phase value into the formula (5), and the distance R corresponding to the position K can be obtained by bringing the obtained target speed into the formula (2), so that the distance speed coupling can be solved.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20070096009A (en) * | 2007-08-07 | 2007-10-01 | 미쓰비시덴키 가부시키가이샤 | Target detecting device |
| JP2010230643A (en) * | 2009-03-03 | 2010-10-14 | Univ Of Electro-Communications | Radar device |
| CN101980046A (en) * | 2010-10-14 | 2011-02-23 | 西安电子科技大学 | Motion compensation method of composite speed measurement of frequency modulation stepping radar |
| CN102224432A (en) * | 2008-11-24 | 2011-10-19 | 奥托里夫Asp股份有限公司 | Method and apparatus for radar signal processing |
| CN105487071A (en) * | 2015-11-23 | 2016-04-13 | 芜湖森思泰克智能科技有限公司 | Multi-moving-object signal processing method based on stepped frequency radar |
| WO2021197960A1 (en) * | 2020-03-31 | 2021-10-07 | Interdigital Ce Intermediate | Methods, apparatuses and systems directed to sensing a target based on a radar processing of a signal |
-
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- 2022-07-27 CN CN202210890729.5A patent/CN115356691B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20070096009A (en) * | 2007-08-07 | 2007-10-01 | 미쓰비시덴키 가부시키가이샤 | Target detecting device |
| CN102224432A (en) * | 2008-11-24 | 2011-10-19 | 奥托里夫Asp股份有限公司 | Method and apparatus for radar signal processing |
| JP2010230643A (en) * | 2009-03-03 | 2010-10-14 | Univ Of Electro-Communications | Radar device |
| CN101980046A (en) * | 2010-10-14 | 2011-02-23 | 西安电子科技大学 | Motion compensation method of composite speed measurement of frequency modulation stepping radar |
| CN105487071A (en) * | 2015-11-23 | 2016-04-13 | 芜湖森思泰克智能科技有限公司 | Multi-moving-object signal processing method based on stepped frequency radar |
| WO2021197960A1 (en) * | 2020-03-31 | 2021-10-07 | Interdigital Ce Intermediate | Methods, apparatuses and systems directed to sensing a target based on a radar processing of a signal |
Non-Patent Citations (2)
| Title |
|---|
| Chirp Sub-pulse Stepped Frequency Radar Signal Processing;Wei Chongyu, et.;《Third International Symposium on Information Processing》;20101017;251-254 * |
| 步进频连续波采样频率跟随技术;郑刚 等;《现代导航》;20120625(第3期);176-181 * |
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