CN113534066B - Method and system for eliminating landing measurement radar altitude multi-reflection wild value - Google Patents

Method and system for eliminating landing measurement radar altitude multi-reflection wild value Download PDF

Info

Publication number
CN113534066B
CN113534066B CN202110697011.XA CN202110697011A CN113534066B CN 113534066 B CN113534066 B CN 113534066B CN 202110697011 A CN202110697011 A CN 202110697011A CN 113534066 B CN113534066 B CN 113534066B
Authority
CN
China
Prior art keywords
radar
landing
value
distance
radial distance
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.)
Active
Application number
CN202110697011.XA
Other languages
Chinese (zh)
Other versions
CN113534066A (en
Inventor
徐秋锋
孙武
贾学振
柯腾伦
丁凯生
陈枭煜
陈睿容
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Beijing Institute of Remote Sensing Equipment
Original Assignee
Beijing Institute of Remote Sensing Equipment
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Beijing Institute of Remote Sensing Equipment filed Critical Beijing Institute of Remote Sensing Equipment
Priority to CN202110697011.XA priority Critical patent/CN113534066B/en
Publication of CN113534066A publication Critical patent/CN113534066A/en
Application granted granted Critical
Publication of CN113534066B publication Critical patent/CN113534066B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

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
    • G01S7/35—Details of non-pulse systems
    • G01S7/352—Receivers
    • G01S7/354—Extracting wanted echo-signals
    • 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
    • G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
    • G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
    • G01S17/06—Systems determining position data of a target
    • G01S17/08—Systems determining position data of a target for measuring distance only
    • G01S17/32—Systems determining position data of a target for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated
    • G01S17/34—Systems determining position data of a target for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal
    • 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
    • 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
    • G01S7/41—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00 using analysis of echo signal for target characterisation; Target signature; Target cross-section
    • G01S7/414—Discriminating targets with respect to background clutter
    • 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)
  • Physics & Mathematics (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Electromagnetism (AREA)
  • Radar Systems Or Details Thereof (AREA)

Abstract

The invention provides a method and a system for eliminating a landing measurement radar altitude multi-reflection field value, wherein the method comprises the following steps: acquiring a radar echo baseband signal of an intermediate frequency signal after digital down conversion, performing FFT processing on the baseband signal, analyzing amplitude-frequency characteristics of a radar echo, and performing radar echo signal gravity center estimation processing to obtain the gravity center of the frequency characteristics of the radar echo; the method comprises the steps of measuring the frequency gravity centers of radar echoes of corresponding beams in a time-sharing mode through a plurality of beams with different angles with the normal direction of a radar antenna, selecting the pointing vectors of at least three beams with the maximum angles between the beam directions and the normal direction of the radar antenna, and resolving the radial distance value of the landing ground to obtain the plane characteristics of the landing ground; and calculating the absolute value of the difference between the distance estimation value from the landing intersection point of the landing ground intersection to the radar and the radial distance value of the beam with the minimum radar antenna normal included angle to the landing ground. The method is simple to realize, and can reject and correct any type of outliers.

Description

Method and system for eliminating landing measurement radar altitude multi-reflection wild value
Technical Field
The invention relates to the technical field of outlier eliminating methods, in particular to a method for eliminating a landing measurement radar height-direction multiple reflection outlier.
Background
The landing measurement radar adopts pseudo code modulated linear frequency modulation interruption continuous wave to perform ranging, and receives and transmits the receiving average power of the asynchronous receiving linear frequency modulation interruption continuous wave radar according to the random signal radar principle
Figure BDA0003128897980000011
The method comprises the following steps:
Figure BDA0003128897980000012
wherein t is 0 For measuring the delay time corresponding to the distance in two passes, T P For symbol width, P r Is the received average power of the chirped continuous wave. In actual operation, in order to ensure complete time sharing of receiving and transmitting, when the receiving switch is switched, a protection time Deltat, deltat < T, is added in the receiving switch time sequence P Then
Figure BDA0003128897980000013
Figure BDA0003128897980000014
Wherein M is more than or equal to 1 and less than 2, and N is more than or equal to 1 and less than or equal to 2.
As can be seen from the above, the closer the distance is, the delay time t of the chirp interruption continuous wave radar is due to asynchronous transceiving 0 The shorter. Landing radar time-sharing four-beam measurement, wherein the pointing angles of three beams are offsetThe distance from the normal direction of the antenna is not less than 30 degrees, and the number of the distance is respectively beam 2, beam 3 and beam 4; the other beam is directed at an angle 5 degrees from the normal to the antenna, numbered beam 1. When landing in close distance, the distance is not more than 50 meters, and the normal direction of the antenna is basically consistent with the gravity direction. When landing ground is flat, the highly reflected clutter is strong, and the direction of the beam 1 is basically consistent with the highly, so that the beam is contained in the main lobe echo at a short distance. The secondary altitude clutter reflection landing platform enters the landing radar through the reflection ground, and the generated delay time is 2t 0 In some cases, the secondary altitude clutter is more powerful than the mainlobe echo. The consequent problems are that under the condition of no prior information, which is the main lobe echo signal and which is the clutter signal can not be judged, so that the landing radar measurement is wrong, the radial distance value of the wave beam 1 is in a wild value, if the scene change is small, the wild value is continuously present, a spot-type wild value is formed, and the wild value elimination algorithm is severely tested. The other three beams have larger beam pointing deviation from the normal direction of the antenna, the height-direction clutter is greatly inhibited by the side lobes of the antenna, the delay time is longer than that of the beam 1, the height-direction clutter is basically covered by noise, and the wild value can not appear in measurement. Aiming at the problem that the landing measurement radar has a high-directional multi-reflection field value in a short-distance gravity beam, the prior proposal lacks an effective means for solving the technical problem.
Disclosure of Invention
The invention aims to provide a method and a system for eliminating a landing measurement radar height-direction multi-reflection wild value, which can solve the problem of the measurement wild value generated by short-distance height-direction multi-reflection.
In view of the above, the present invention provides a method for rejecting a landing measurement radar altitude-to-multiple reflection field value, which is characterized by comprising:
acquiring a radar echo baseband signal of an intermediate frequency signal after digital down conversion, performing FFT processing on the baseband signal, performing CFAR detection based on the FFT processing result, judging whether radar echo exists, if not, ending, otherwise, giving an identification of the existence of the radar echo;
analyzing amplitude-frequency characteristics of the radar echo according to the identification of the radar echo, and performing radar echo signal gravity center estimation processing by utilizing the amplitude-frequency characteristics of the radar echo to obtain the gravity center of the frequency characteristics of the radar echo;
measuring the frequency gravity centers of radar echoes of corresponding beams in a time-sharing manner through a plurality of beams with different angles with the normal direction of a radar antenna to obtain radial distance values of each beam against the land, and selecting the pointing vectors of at least three beams with the largest angles between the beam directions and the normal direction of the radar antenna to calculate the radial distance values of the land so as to obtain the plane characteristics of the land;
analyzing the plane characteristics of the landing ground, and calculating an estimated value of the distance from the landing intersection point intersected with the landing ground to the radar according to a pointing unit vector of a wave beam with the minimum included angle between the wave beam direction and the normal direction of the radar antenna;
calculating the absolute value of the difference between the distance estimation value of the intersection point of the landing ground and the radar and the radial distance value of the beam with the minimum normal angle of the radar antenna to the landing ground, and when the absolute value of the difference is larger than a certain threshold, judging that the radial distance value of the beam with the minimum normal angle of the radar antenna to the landing ground is a reflection wild value, at the moment, replacing the radial distance value of the beam with the minimum normal angle of the radar antenna to the landing ground with the distance of the intersection point of the landing ground to the radar, and obtaining the actual measurement value of the distance of the intersection point of the radar with the landing ground to the radar.
Further, the method further comprises the following steps: and calculating the width of a radar echo signal at the current moment according to the actual measurement value of the distance from the landing intersection point intersected with the landing ground to the radar and the incident angle of each beam to the land, and calculating the amplitude-frequency characteristic of the radar echo of the next measuring period.
Further, performing FFT processing on the baseband signal, including: and respectively carrying out FFT processing on the positive and negative frequency modulation received signals subjected to dechirp processing and quadrature down-conversion to obtain FFT processing results.
Further, performing CFAR detection to determine whether radar echo exists, including: opening a detection window with the width of N sampling points near the maximum amplitude of the FFT processing result, and judging that the detection window passes through CFAR detection if M sampling points are judged to pass through a detection threshold in the detection window, wherein N is more than or equal to M and more than or equal to 1; if no M sampling points in the detection window can pass the detection threshold, the CFAR detection is judged not to pass.
Further, the radar echo signal center of gravity estimation processing is performed by using the amplitude-frequency characteristic of the radar echo, including:
firstly, acquiring a waveguide gate center, a beam proximal width and a beam distal width;
then, a beam with a near side width W is opened up near the center of the wave gate near A plurality of sampling points and a beam distal width W far And a detection window of each sampling point, and center of gravity estimation processing is carried out on the detection window to obtain the center of gravity of the echo signal.
Further, the method for measuring the frequency center of gravity of the radar echo of the corresponding beam in a time-sharing manner through a plurality of beams with different angles from the normal direction of the radar antenna comprises the following steps: and judging the validity of radial distance values of at least three beams with the maximum included angles between the beam directions and the normal directions of the radar antennas.
Further, determining the validity of radial distance values of at least three beams with the maximum included angles between the beam directions and the normal direction of the radar antenna comprises:
firstly, at least three beams with the largest included angles between the beam direction and the normal direction of a radar antenna are measured in a time-sharing mode, and the radial distance to the ground is obtained respectively;
then, measuring the beam with the smallest included angle between the beam direction and the normal direction of the radar antenna to obtain the radial distance to the ground, completing the measurement of four beams to be a complete current measurement period, and starting to perform distance validity judgment when the next measurement period is reached;
and finally, calculating to obtain the absolute value of the distance difference between the front measuring period and the rear measuring period of the same beam.
Another object of the present invention is to provide a landing measurement radar altitude-to-multiple reflection outlier rejection system, characterized by comprising:
the acquisition unit is used for acquiring a radar echo baseband signal after the intermediate frequency signal is subjected to digital down conversion, carrying out FFT processing on the baseband signal, carrying out CFAR detection based on the FFT processing result, judging whether radar echo exists, if not, ending, otherwise, giving an identification of the existence of the radar echo;
the analysis unit is used for analyzing the amplitude-frequency characteristics of the radar echo according to the identification of the radar echo, and carrying out radar echo signal gravity center estimation processing by utilizing the amplitude-frequency characteristics of the radar echo to obtain the gravity center of the frequency characteristics of the radar echo;
the calculation unit is used for measuring the frequency gravity centers of the radar echoes of the corresponding beams in a time-sharing manner through a plurality of beams with different angles with the normal direction of the radar antenna to obtain radial distance values of the corresponding beams to the landing ground, and selecting the pointing vectors of at least three beams with the maximum angles between the beam directions and the normal direction of the radar antenna to calculate the radial distance values of the landing ground to obtain the plane characteristics of the landing ground;
the estimating unit is used for analyzing the plane characteristics of the landing ground and calculating an estimated value of the distance from the landing intersection point intersected with the landing ground to the radar according to the pointing unit vector of the wave beam with the minimum included angle between the wave beam direction and the normal direction of the radar antenna;
and the determining unit is used for calculating the absolute value of the difference between the distance estimation value of the landing intersection point of the landing ground intersection to the radar and the radial distance value of the beam with the minimum normal included angle of the radar antenna to the land surface, and judging that the radial distance value of the beam with the minimum normal included angle of the radar antenna to the land surface is a reflection wild value when the absolute value of the difference is larger than a certain threshold, and at the moment, replacing the radial distance value of the beam with the minimum normal included angle of the radar antenna to the land surface with the distance of the landing intersection point of the landing ground intersection to the radar to obtain the actual measurement value of the distance of the landing intersection point of the landing ground intersection to the radar.
Further, the determining unit comprises an outlier eliminating module, which is used for eliminating the outlier of the beam measurement result with the minimum normal included angle with the radar antenna according to the estimated distance of the beam with the minimum normal included angle with the radar antenna in the measuring period.
Further, the method also comprises an iteration unit, which is used for calculating the width of the radar echo signal at the current moment according to the actual measurement value of the distance from the landing intersection point intersected with the landing ground to the radar and the incidence angle of each beam to the landing ground, and calculating the amplitude-frequency characteristic of the radar echo of the next measuring period.
The invention realizes the following remarkable beneficial effects:
the realization is simple, including: acquiring a radar echo baseband signal of an intermediate frequency signal after digital down conversion, performing FFT processing on the baseband signal, performing CFAR detection based on the FFT processing result, judging whether radar echo exists, if not, ending, otherwise, giving an identification of the existence of the radar echo; analyzing amplitude-frequency characteristics of the radar echo according to the identification of the radar echo, and performing radar echo signal gravity center estimation processing by utilizing the amplitude-frequency characteristics of the radar echo to obtain the gravity center of the frequency characteristics of the radar echo; measuring the frequency gravity centers of radar echoes of corresponding beams in a time-sharing manner through a plurality of beams with different angles with the normal direction of a radar antenna to obtain radial distance values of each beam against the land, and selecting the pointing vectors of at least three beams with the largest angles between the beam directions and the normal direction of the radar antenna to calculate the radial distance values of the land so as to obtain the plane characteristics of the land; analyzing the plane characteristics of the landing ground, and calculating an estimated value of the distance from the landing intersection point intersected with the landing ground to the radar according to a pointing unit vector of a wave beam with the minimum included angle between the wave beam direction and the normal direction of the radar antenna; calculating the absolute value of the difference between the distance estimation value of the intersection point of the landing ground and the radar and the radial distance value of the beam with the minimum normal angle of the radar antenna to the landing ground, and when the absolute value of the difference is larger than a certain threshold, judging that the radial distance value of the beam with the minimum normal angle of the radar antenna to the landing ground is a reflection wild value, at the moment, replacing the radial distance value of the beam with the minimum normal angle of the radar antenna to the landing ground with the distance of the intersection point of the landing ground to the radar, and obtaining the actual measurement value of the distance of the intersection point of the radar with the landing ground to the radar. The wild value can be judged and corrected by a relatively accurate estimated distance, and the result after the wild value is removed is fed back to the gate selection of the next measuring period to prevent the misunderstanding of the next measuring period.
Drawings
FIG. 1 is a flow chart of a method for eliminating the altitude-to-multiple reflection field value of a landing measurement radar according to the present invention;
fig. 2 is a schematic structural diagram of a landing measurement radar altitude-to-multiple reflection outlier rejection system according to the present invention.
Reference numerals indicate
1-FFT processing module 2-CFAR detection module 3-OCOG processing module 4-measuring distance dissociation calculation module
5- -distance effectiveness decision module 6- -estimated distance dissociation calculation module 7- -outlier rejection module
8-radial distance value feedback module
Description of the preferred embodiments
The advantages and features of the present invention will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings and detailed description. It should be noted that the drawings are in a very simplified form and are adapted to non-precise proportions, merely for the purpose of facilitating and clearly aiding in the description of embodiments of the invention.
It should be noted that, in order to clearly illustrate the present invention, various embodiments of the present invention are specifically illustrated by the present embodiments to further illustrate different implementations of the present invention, where the various embodiments are listed and not exhaustive. Furthermore, for simplicity of explanation, what has been mentioned in the previous embodiment is often omitted in the latter embodiment, and therefore, what has not been mentioned in the latter embodiment can be referred to the previous embodiment accordingly.
While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood that the invention is not to be limited to the particular embodiments disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit or scope of the invention as defined by the appended claims. The same element numbers may be used throughout the drawings to refer to the same or like parts.
Referring to fig. 1, the method for removing the altitude-direction multiple reflection field value of the landing measurement radar of the present invention includes:
step S101, obtaining a radar echo baseband signal of an intermediate frequency signal after digital down conversion, carrying out FFT processing on the baseband signal, carrying out CFAR detection based on the FFT processing result, judging whether radar echo exists, if not, ending, otherwise, giving an identification of the existence of the radar echo;
step S102, analyzing amplitude-frequency characteristics of the radar echo according to the identification of the radar echo, and performing radar echo signal gravity center estimation processing by utilizing the amplitude-frequency characteristics of the radar echo to obtain the gravity center of the frequency characteristics of the radar echo;
step S103, measuring the frequency gravity centers of radar echoes of corresponding beams in a time-sharing manner through a plurality of beams with different angles from the normal direction of a radar antenna to obtain radial distance values of each beam against the land, and selecting at least three directional vectors of the beams with the largest angles between the beam directions and the normal direction of the radar antenna to calculate the radial distance values of the land so as to obtain the plane characteristics of the land;
step S104, analyzing the plane characteristics of the landing ground, and calculating an estimated value of the distance from the radar to a landing intersection point intersected with the landing ground according to a pointing unit vector of a beam with the minimum included angle between the beam direction and the normal direction of the radar antenna;
step 105, calculating the absolute value of the difference between the distance estimation value from the landing intersection point of the landing ground intersection to the radar and the radial distance value of the beam with the minimum normal angle of the radar antenna to the land surface, when the absolute value of the difference is larger than a certain threshold, determining that the radial distance value of the beam with the minimum normal angle of the radar antenna to the land surface is a reflection wild value, and at the moment, replacing the radial distance value of the beam with the minimum normal angle of the radar antenna to the land surface with the distance from the landing intersection point of the landing ground intersection to the radar to obtain the actual measurement value of the distance from the landing intersection point of the landing ground intersection to the radar.
In one embodiment of the present application, specifically, further includes: and calculating the width of a radar echo signal at the current moment according to the actual measurement value of the distance from the landing intersection point intersected with the landing ground to the radar and the incident angle of each beam to the land, and calculating the amplitude-frequency characteristic of the radar echo of the next measuring period.
In one embodiment of the present application, specifically, performing FFT processing on the baseband signal includes: and respectively carrying out FFT processing on the positive and negative frequency modulation received signals subjected to dechirp processing and quadrature down-conversion to obtain FFT processing results.
In one embodiment of the present application, specifically, performing CFAR detection, determining whether radar echo is present includes: opening a detection window with the width of N sampling points near the maximum amplitude of the FFT processing result, and judging that the detection window passes through CFAR detection if M sampling points are judged to pass through a detection threshold in the detection window, wherein N is more than or equal to M and more than or equal to 1; if no M sampling points in the detection window can pass the detection threshold, the CFAR detection is judged not to pass.
In an embodiment of the present application, specifically, using the amplitude-frequency characteristic of the radar echo, the radar echo signal center of gravity estimation processing includes:
firstly, acquiring a waveguide gate center, a beam proximal width and a beam distal width;
then, a beam with a near side width W is opened up near the center of the wave gate near A plurality of sampling points and a beam distal width W far A detection window of sampling points, in which detectionAnd carrying out gravity center estimation processing on the window to obtain the gravity center of the echo signal.
In one embodiment of the present application, specifically, measuring the frequency center of gravity of the radar echo of the corresponding beam in a time-sharing manner through a plurality of beams having different angles from the normal direction of the radar antenna includes: and judging the validity of radial distance values of at least three beams with the maximum included angles between the beam directions and the normal directions of the radar antennas.
In one embodiment of the present application, specifically, determining the validity of radial distance values of at least three beams in which the beam direction has the largest angle with the radar antenna normal direction includes:
firstly, at least three beams with the largest included angles between the beam direction and the normal direction of a radar antenna are measured in a time-sharing mode, and the radial distance to the ground is obtained respectively;
then, measuring the beam with the smallest included angle between the beam direction and the normal direction of the radar antenna to obtain the radial distance to the ground, completing the measurement of four beams to be a complete current measurement period, and starting to perform distance validity judgment when the next measurement period is reached;
and finally, calculating to obtain the absolute value of the distance difference between the front measuring period and the rear measuring period of the same beam.
Another object of the present invention is to provide a landing measurement radar altitude-to-multiple reflection outlier rejection system, comprising:
the acquisition unit is used for acquiring a radar echo baseband signal after the intermediate frequency signal is subjected to digital down conversion, carrying out FFT processing on the baseband signal, carrying out CFAR detection based on the FFT processing result, judging whether radar echo exists, if not, ending, otherwise, giving an identification of the existence of the radar echo;
the analysis unit is used for analyzing the amplitude-frequency characteristics of the radar echo according to the identification of the radar echo, and carrying out radar echo signal gravity center estimation processing by utilizing the amplitude-frequency characteristics of the radar echo to obtain the gravity center of the frequency characteristics of the radar echo;
the calculation unit is used for measuring the frequency gravity centers of the radar echoes of the corresponding beams in a time-sharing manner through a plurality of beams with different angles with the normal direction of the radar antenna to obtain radial distance values of the corresponding beams to the landing ground, and selecting the pointing vectors of at least three beams with the maximum angles between the beam directions and the normal direction of the radar antenna to calculate the radial distance values of the landing ground to obtain the plane characteristics of the landing ground;
the estimating unit is used for analyzing the plane characteristics of the landing ground and calculating an estimated value of the distance from the landing intersection point intersected with the landing ground to the radar according to the pointing unit vector of the wave beam with the minimum included angle between the wave beam direction and the normal direction of the radar antenna;
and the determining unit is used for calculating the absolute value of the difference between the distance estimation value of the landing intersection point of the landing ground intersection to the radar and the radial distance value of the beam with the minimum normal included angle of the radar antenna to the land surface, and judging that the radial distance value of the beam with the minimum normal included angle of the radar antenna to the land surface is a reflection wild value when the absolute value of the difference is larger than a certain threshold, and at the moment, replacing the radial distance value of the beam with the minimum normal included angle of the radar antenna to the land surface with the distance of the landing intersection point of the landing ground intersection to the radar to obtain the actual measurement value of the distance of the landing intersection point of the landing ground intersection to the radar.
In an embodiment of the present application, specifically, the determining unit includes a outlier rejection module, configured to complete outlier rejection processing of a beam measurement result with a minimum normal angle with the radar antenna according to an estimated distance of a beam with a minimum normal angle with the radar antenna in the measurement period.
In an embodiment of the present application, specifically, the method further includes an iteration unit, configured to calculate a radar echo signal width at a current moment according to an actual measurement value of a distance from a landing intersection point intersecting with the landing ground to the radar and an incident angle of each beam against the landing ground, and calculate an amplitude-frequency characteristic of a radar echo of a next measurement period.
The invention adopts redundant measurement information of landing radar multi-beam measurement to remove the wild value of the near gravity beam. The method for eliminating the altitude multi-reflection wild value of the landing measurement radar comprises the following steps of:
the system comprises an FFT processing module 1, a CFAR detection module 2, an OCOG processing module 3, a measurement distance resolving module 4, a distance effectiveness judging module 5, an estimated distance dissociation calculating module 6, a outlier rejecting module 7 and a radial distance value feedback module 8, wherein:
the measurement result of the FFT processing module 1 is output to the CFAR detection module 2, the detection result of the CFAR detection module 2 is output to the OCOG processing module 3, the solution result of the OCOG processing module 3 is output to the measurement distance solution module 4, the measurement result of the measurement distance solution module 4 is output to the distance validity judgment module 5, the judgment result of the distance validity judgment module 5 is output to the estimated distance dissociation calculation module 6, the solution result of the estimated distance dissociation calculation module 6 is output to the outlier rejection module 7, the processing result of the outlier rejection module 7 is output to the radial distance value feedback module 8, and the feedback result of the radial distance value feedback module 8 is output to the OCOG processing module 3;
the landing radar firstly measures a beam 2, a beam 3 and a beam 4, and then measures a beam 1;
the estimated distance dissociation calculation module 6 obtains the estimated distance of the beam 1 according to the combined solution of the effective distances of the beam 2, the beam 3 and the beam 4 in the measurement period;
the outlier eliminating module 7 completes outlier eliminating processing of the beam 1 measurement result according to the estimated distance of the beam 1 in the measurement period.
The radial distance value feedback module 8 completes the gate selection of the next measurement period according to the radial distance value of the current measurement period.
The following describes the execution system of each step of the preferred embodiment of the present invention in detail:
in one embodiment, the FFT processing module 1 performs N on the positive and negative fm received signals s (t) after the dechirp processing and quadrature down-conversion, respectively FFT And (3) carrying out point FFT processing to obtain an FFT processing result S (f), wherein the formula is as follows:
S(f)＝FFT{s(t)}
formula (1);
in one embodiment, the CFAR detection module 2 performs CFAR detection on the FFT processing result S (f), opens up a detection window with a width of N sampling points near the maximum amplitude of S (f), and if M sampling points are judged to pass through a detection threshold in the detection window, N is greater than or equal to M and greater than or equal to 1, then judges that the detection is performed through CFAR; if no M sampling points in the detection window can pass the detection threshold, the CFAR detection is judged not to pass.
In one embodiment, after CFAR detection, the center k of the wave gate is obtained by a solution from the radial distance value feedback module 8 Z Beam proximal width W near And beam distal width W far At the center k of the wave gate Z The near side of a beam is opened up to be W near A plurality of sampling points and a beam distal width W far Detecting window of sampling points, and performing OCOG processing on the detecting window to obtain the gravity center of echo signals
Figure BDA0003128897980000101
Figure BDA0003128897980000102
Formula (2); s (f) m ) For FFT result, FFT frequency point m E [ R ] left ,R right ]。
Wherein k is Z Negative number, k, in positive frequency modulation Z Positive numbers when negative frequency modulation is performed; left radius
Figure BDA0003128897980000103
Right radius>
Figure BDA0003128897980000104
P n The mean value of noise is calculated outside the detection window n ：
Figure BDA0003128897980000105
Formula (3);
wherein the noise statistics range
Figure BDA0003128897980000106
Constant N y ≥10，N lpf The number of FFT frequency points corresponding to the bandwidth of the intermediate frequency filter.
Center of gravity of actual echo signal
Figure BDA0003128897980000107
The average of the respective barycenter of the positive and negative frequency modulation echo signals is as follows:
Figure BDA0003128897980000108
formula (4);
wherein, the liquid crystal display device comprises a liquid crystal display device,
Figure BDA0003128897980000111
the center of gravity of the positive frequency modulation echo signal; />
Figure BDA0003128897980000112
The center of gravity of the negative frequency modulation echo signal is positive.
In one embodiment, the radial distance value is calculated by the measured distance dissociation module 4. The OCOG processing module 3 calculates the processing result
Figure BDA0003128897980000113
The radial distance value R of the wave beam k is obtained by calculation k K=1, 2,3,4, the formula is as follows:
Figure BDA0003128897980000114
formula (5);
wherein Δf FFT Frequency resolution for FFT; k (k) LFM Is the slope of the chirp signal; c is the speed of light.
In one embodiment, the validity of the radial distance values for beam 2, beam 3, and beam 4 is determined by distance validity determination module 5.
Firstly, measuring a beam 2, a beam 3 and a beam 4 in a time sharing way to obtain a radial distance R to the ground 2 、R 3 And R is 4 The method comprises the steps of carrying out a first treatment on the surface of the And measuring beam 1 again to obtain a radial distance R to ground 1 And completing the measurement of the four beams as a complete measurement period, and starting to perform distance validity judgment when the second measurement period is reached. T th k When measuring the period, the absolute value delta R of the distance difference between the front measuring period and the rear measuring period of the same beam is obtained by calculation k ：
ΔR k ＝|R k (t k )-R k (t k-1 )| k＝2,3,4
Formula (6); r is R k (t k ) For beam k (k e 1,4]) At t k Radial distance of time.
If DeltaR k ＜μ 1 R k (t k )+μ 2 ，0.15≤μ 1 ≤0.25，μ 2 1. Gtoreq., t of beam k k The distance measurement data of each measurement period is valid; otherwise, the data is invalid, and the radial distance value feedback module 8 is reinitialized.
In one embodiment, if the data for beam 2, beam 3, and beam 4 are all valid, then the estimated distance for beam 1 is resolved by the estimated distance-resolving module 6.
Since the beam pointing angles of the beam 2, the beam 3 and the beam 4 in the rectangular coordinate system of the landing radar antenna are known, the beam pointing unit vector of the beam 2, the beam 3 and the beam 4 is vec 2 、vec 3 And vec 4 ：
Figure BDA0003128897980000121
Formula (7);
wherein alpha is k The angle of elevation of the beam k in the rectangular coordinate system of the landing radar antenna is defined as the included angle between the beam pointing and the projection of the beam pointing on the XY plane; beta k The directional azimuth angle of the beam k under the rectangular coordinate system of the landing radar antenna is defined as the included angle between the projection of the beam pointing on the XY plane and the X axis;
from this, beam 2, beam 3, beam 4 phases are availableThe beam pointing vector to the ground is R 2 vec 2 、R 3 vec 3 And R is 4 vec 4 。
Since the high-order reflection clutter of beam 1 occurs substantially under ground leveling conditions, it is a reasonable assumption to assume that the ground is a plane. The normalized ground plane equation can be determined according to the directional vectors of the beam 2, the beam 3 and the beam 4 relative to the ground:
ax+by+cz＝1
formula (8);
where a, b, c are constants describing the spatial characteristics of the ground plane.
The constants of the ground plane spatial features are solved as:
Figure BDA0003128897980000122
formula (9);
according to the known ground plane equation ax+by+cz=1, since the beam pointing angle of the beam 1 is known, the beam pointing unit vector of the beam 1 is obtained as vec 1 ：
vec 1 ＝[cos(α 1 )cos(β 1 ) cos(α 1 )sin(β 1 ) sin(α 1 )]
Formula (10);
then the linear equation for beam 1 can be derived:
Figure BDA0003128897980000131
formula (11);
the ground plane equation and the linear equation of the beam 1 are jointly solved to obtain the intersection point coordinate [ x ] of the beam 1 pointing on the ground 1 y 1 z 1 ]Then the estimated distance R of beam 1 can be obtained 1ref ：
Figure BDA0003128897980000132
Formula (12);
in one embodiment, the outlier rejection module 7 is based on the estimated distance R 1ref Performing outlier rejection on the radial distance value of the beam 1, and calculating the radial distance value R of the beam 1 1 And estimated distance R 1ref Is a difference DeltaR of (1) 1 ：
ΔR 1 ＝|R 1 -R 1ref |
Formula (13);
if DeltaR 1 ＜γ 1 R 1ref +γ 2 ，0.15≤γ 1 ≤0.25，γ 2 The radial distance value of the wave beam 1 is effective if the radial distance value is not less than 1; otherwise, the radial distance value of beam 1 is invalidated to estimate distance R 1ref As radial distance value of beam 1, i.e. R 1 ＝R 1ref 。
In one embodiment, the beam center and beam width of the next measurement period are solved by the radial distance value feedback module 8.
During the first measurement period after starting measurement or data invalidation, the frequency point with the maximum amplitude of S (f) is taken as the beam center k Z 。
At t k After a measuring period t k Not less than 2, at t k R of each measurement period k Estimating the beam center k of the next measurement period Z ：
Figure BDA0003128897980000133
Formula (14);
wherein Round [ ] is a rounding operation.
While the beam proximal width W near And beam distal width W far The solution formula of (2) is as follows:
Figure BDA0003128897980000141
formula (15);
wherein the method comprises the steps ofConstant 0.45.ltoreq.eta 1 A constant of 0.5.ltoreq.eta.0.5 2 A constant 2.ltoreq.η of 0.8 3 ≤10。
In summary, in the invention, the estimated distance of the beam 1 is obtained through the distance measurement information of the beam 2, the beam 3 and the beam 4, the wild value can be judged and corrected by comparing the estimated distance with the actually measured distance, and the wild value is fed back to the gate selection of the next measurement period according to the result after the wild value is removed, so that the misunderstanding of the next measurement period is prevented, the wild value removing algorithm fully utilizes the measurement redundant information of the landing radar, and any type of wild value of the beam 1 can be removed and corrected.
From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:
the realization is simple, including: acquiring a radar echo baseband signal of an intermediate frequency signal after digital down conversion, performing FFT processing on the baseband signal, performing CFAR detection based on the FFT processing result, judging whether radar echo exists, if not, ending, otherwise, giving an identification of the existence of the radar echo; analyzing amplitude-frequency characteristics of the radar echo according to the identification of the radar echo, and performing radar echo signal gravity center estimation processing by utilizing the amplitude-frequency characteristics of the radar echo to obtain the gravity center of the frequency characteristics of the radar echo; measuring the frequency gravity centers of radar echoes of corresponding beams in a time-sharing manner through a plurality of beams with different angles with the normal direction of a radar antenna to obtain radial distance values of each beam against the land, and selecting the pointing vectors of at least three beams with the largest angles between the beam directions and the normal direction of the radar antenna to calculate the radial distance values of the land so as to obtain the plane characteristics of the land; analyzing the plane characteristics of the landing ground, and calculating an estimated value of the distance from the landing intersection point intersected with the landing ground to the radar according to a pointing unit vector of a wave beam with the minimum included angle between the wave beam direction and the normal direction of the radar antenna; calculating the absolute value of the difference between the distance estimation value of the intersection point of the landing ground and the radar and the radial distance value of the beam with the minimum normal angle of the radar antenna to the landing ground, and when the absolute value of the difference is larger than a certain threshold, judging that the radial distance value of the beam with the minimum normal angle of the radar antenna to the landing ground is a reflection wild value, at the moment, replacing the radial distance value of the beam with the minimum normal angle of the radar antenna to the landing ground with the distance of the intersection point of the landing ground to the radar, and obtaining the actual measurement value of the distance of the intersection point of the radar with the landing ground to the radar. The wild value can be judged and corrected by a relatively accurate estimated distance, and the result after the wild value is removed is fed back to the gate selection of the next measuring period to prevent the misunderstanding of the next measuring period.
Any other suitable modification may also be made according to the technical solution and the idea of the invention. All such alternatives, modifications and improvements will readily occur to those skilled in the art and are intended to be within the scope of the invention as defined in the appended claims.

Claims (10)

1. A method for eliminating the altitude multi-reflection wild value of a landing measurement radar is characterized by comprising the following steps:
acquiring a radar echo baseband signal of an intermediate frequency signal after digital down conversion, performing FFT processing on the baseband signal, performing CFAR detection based on the FFT processing result, judging whether radar echo exists, if not, ending, otherwise, giving an identification of the existence of the radar echo;
analyzing amplitude-frequency characteristics of the radar echo according to the identification of the radar echo, and performing radar echo signal gravity center estimation processing by utilizing the amplitude-frequency characteristics of the radar echo to obtain the gravity center of the frequency characteristics of the radar echo;
measuring the frequency gravity centers of radar echoes of corresponding beams in a time-sharing manner through a plurality of beams with different angles with the normal direction of a radar antenna to obtain radial distance values of each beam against the land, and selecting the pointing vectors of at least three beams with the largest angles between the beam directions and the normal direction of the radar antenna to calculate the radial distance values of the land so as to obtain the plane characteristics of the land;
analyzing the plane characteristics of the landing ground, and calculating an estimated value of the distance from the landing intersection point intersected with the landing ground to the radar according to a pointing unit vector of a wave beam with the minimum included angle between the wave beam direction and the normal direction of the radar antenna;
calculating the absolute value of the difference between the distance estimation value of the intersection point of the landing ground and the radar and the radial distance value of the beam with the minimum normal angle of the radar antenna to the landing ground, and when the absolute value of the difference is larger than a certain threshold, judging that the radial distance value of the beam with the minimum normal angle of the radar antenna to the landing ground is a reflection wild value, at the moment, replacing the radial distance value of the beam with the minimum normal angle of the radar antenna to the landing ground with the distance of the intersection point of the landing ground to the radar, and obtaining the actual measurement value of the distance of the intersection point of the radar with the landing ground to the radar.
2. The method for removing the altitude-to-multiple reflection field value of the landing measurement radar according to claim 1, further comprising: and calculating the width of a radar echo signal at the current moment according to the actual measurement value of the distance from the landing intersection point intersected with the landing ground to the radar and the incident angle of each beam to the land, and calculating the amplitude-frequency characteristic of the radar echo of the next measuring period.
3. The method for removing the altitude-to-multiple reflection field value of the landing measurement radar according to claim 1, wherein performing FFT processing on the baseband signal comprises: and respectively carrying out FFT processing on the positive and negative frequency modulation received signals subjected to dechirp processing and quadrature down-conversion to obtain FFT processing results.
4. The method for removing the altitude of the landing measurement radar from the multiple reflection field as set forth in claim 3, wherein performing CFAR detection to determine whether radar echo is present comprises: opening a detection window with the width of N sampling points near the maximum amplitude of the FFT processing result, and judging that the detection window passes through CFAR detection if M sampling points are judged to pass through a detection threshold in the detection window, wherein N is more than or equal to M and more than or equal to 1; if no M sampling points in the detection window can pass the detection threshold, the CFAR detection is judged not to pass.
5. The method for removing the altitude value of the landing measurement radar from the multiple reflection field of claim 4, wherein the radar echo signal center of gravity estimation processing is performed by using the amplitude-frequency characteristic of the radar echo, and the method comprises the following steps:
firstly, acquiring a waveguide gate center, a beam proximal width and a beam distal width;
then, a beam with a near side width W is opened up near the center of the wave gate near A plurality of sampling points and a beam distal width W far And a detection window of each sampling point, and center of gravity estimation processing is carried out on the detection window to obtain the center of gravity of the echo signal.
6. The method of claim 5, wherein measuring the frequency center of gravity of the radar echo of the corresponding beam in a time-sharing manner by a plurality of beams having different angles from the normal direction of the radar antenna, comprises: and judging the validity of radial distance values of at least three beams with the maximum included angles between the beam directions and the normal directions of the radar antennas.
7. The method of claim 6, wherein determining the validity of the radial distance values of at least three beams having the greatest beam direction and radar antenna normal angle comprises:
firstly, at least three beams with the largest included angles between the beam direction and the normal direction of a radar antenna are measured in a time-sharing mode, and the radial distance to the ground is obtained respectively;
then, measuring the beam with the smallest included angle between the beam direction and the normal direction of the radar antenna to obtain the radial distance to the ground, completing the measurement of four beams to be a complete current measurement period, and starting to perform distance validity judgment when the next measurement period is reached;
and finally, calculating to obtain the absolute value of the distance difference between the front measuring period and the rear measuring period of the same beam.
8. A landing measurement radar altitude-to-multiple reflection outlier rejection system, comprising:
the acquisition unit is used for acquiring a radar echo baseband signal after the intermediate frequency signal is subjected to digital down conversion, carrying out FFT processing on the baseband signal, carrying out CFAR detection based on the FFT processing result, judging whether radar echo exists, if not, ending, otherwise, giving an identification of the existence of the radar echo;
the analysis unit is used for analyzing the amplitude-frequency characteristics of the radar echo according to the identification of the radar echo, and carrying out radar echo signal gravity center estimation processing by utilizing the amplitude-frequency characteristics of the radar echo to obtain the gravity center of the frequency characteristics of the radar echo;
the calculation unit is used for measuring the frequency gravity centers of the radar echoes of the corresponding beams in a time-sharing manner through a plurality of beams with different angles with the normal direction of the radar antenna to obtain radial distance values of the corresponding beams to the landing ground, and selecting the pointing vectors of at least three beams with the maximum angles between the beam directions and the normal direction of the radar antenna to calculate the radial distance values of the landing ground to obtain the plane characteristics of the landing ground;
the estimating unit is used for analyzing the plane characteristics of the landing ground and calculating an estimated value of the distance from the landing intersection point intersected with the landing ground to the radar according to the pointing unit vector of the wave beam with the minimum included angle between the wave beam direction and the normal direction of the radar antenna;
and the determining unit is used for calculating the absolute value of the difference between the distance estimation value of the landing intersection point of the landing ground intersection to the radar and the radial distance value of the beam with the minimum normal included angle of the radar antenna to the land surface, and judging that the radial distance value of the beam with the minimum normal included angle of the radar antenna to the land surface is a reflection wild value when the absolute value of the difference is larger than a certain threshold, and at the moment, replacing the radial distance value of the beam with the minimum normal included angle of the radar antenna to the land surface with the distance of the landing intersection point of the landing ground intersection to the radar to obtain the actual measurement value of the distance of the landing intersection point of the landing ground intersection to the radar.
9. The system for removing the outlier from the altitude of the landing measurement radar according to claim 8, wherein the determining unit includes an outlier removing module configured to perform outlier removing processing on the beam measurement result having the smallest angle with the normal direction of the radar antenna according to the estimated distance of the beam having the smallest angle with the normal direction of the radar antenna in the present measurement period.
10. The system for removing the altitude value of the landing measurement radar from the multiple reflection field value according to claim 8, further comprising an iteration unit for calculating the amplitude-frequency characteristic of the radar echo of the next measurement period based on the actual measurement value of the distance from the landing intersection point intersecting the landing ground to the radar, and the incident angle of each beam to the land surface.
CN202110697011.XA 2021-06-23 2021-06-23 Method and system for eliminating landing measurement radar altitude multi-reflection wild value Active CN113534066B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110697011.XA CN113534066B (en) 2021-06-23 2021-06-23 Method and system for eliminating landing measurement radar altitude multi-reflection wild value

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110697011.XA CN113534066B (en) 2021-06-23 2021-06-23 Method and system for eliminating landing measurement radar altitude multi-reflection wild value

Publications (2)

Publication Number Publication Date
CN113534066A CN113534066A (en) 2021-10-22
CN113534066B true CN113534066B (en) 2023-06-20

Family

ID=78096425

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110697011.XA Active CN113534066B (en) 2021-06-23 2021-06-23 Method and system for eliminating landing measurement radar altitude multi-reflection wild value

Country Status (1)

Country Link
CN (1) CN113534066B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115371719B (en) * 2022-10-10 2023-01-24 福思(杭州)智能科技有限公司 Parameter calibration method and device for detection equipment, storage medium and electronic device

Citations (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101493526A (en) * 2008-11-28 2009-07-29 北京工业大学 Lunar vehicle high speed three-dimensional laser imaging radar system and imaging method
CN101960327A (en) * 2008-02-25 2011-01-26 Iad信息自动化及数据处理有限公司 Carry out the apparatus and method that direction is estimated and decoded by means of the secondary radar signal with improvement
CN102384755A (en) * 2010-09-02 2012-03-21 何平 High-accuracy method for measuring instant navigational speed of airborne phased array whether radar
CN102506892A (en) * 2011-11-08 2012-06-20 北京航空航天大学 Configuration method for information fusion of a plurality of optical flow sensors and inertial navigation device
CN102866397A (en) * 2012-10-12 2013-01-09 中国测绘科学研究院 Combined positioning method for multisource heterogeneous remote sensing image
CN105277974A (en) * 2014-07-23 2016-01-27 中国石油化工股份有限公司 Stratum data interpolation method
CN108132461A (en) * 2017-10-13 2018-06-08 西安电子科技大学 Inhibit the method for CW with frequency modulation landing radar direct current leakage
CN108196221A (en) * 2017-12-20 2018-06-22 北京遥感设备研究所 A kind of elimination of burst noise method based on multi-baseline interference instrument direction ambiguity section
CN108802716A (en) * 2017-12-29 2018-11-13 西安电子科技大学 CW with frequency modulation landing radar distance measuring method based on center of gravity correction
CN109839623A (en) * 2019-02-14 2019-06-04 北京遥感设备研究所 A kind of objects outside Earth landing instrumentation radar Area Objects echo-signal ranging processing method
CN110095760A (en) * 2019-04-24 2019-08-06 中国气象局气象探测中心 A kind of test device and method of weather radar
CN110261857A (en) * 2019-07-17 2019-09-20 南京信息工程大学 A kind of weather radar spatial interpolation methods
CN110554375A (en) * 2019-08-22 2019-12-10 北京遥感设备研究所 Phased array radar for measuring landing of extraterrestrial celestial body
CN111381239A (en) * 2018-12-29 2020-07-07 华为技术有限公司 Laser measurement module and laser radar
CN111879545A (en) * 2020-09-01 2020-11-03 中国科学院空天信息创新研究院 Ground laboratory remote sensing flight simulation platform and control method
CN112368663A (en) * 2019-11-04 2021-02-12 深圳市大疆创新科技有限公司 Terrain prediction method and device for sloping field, radar, unmanned aerial vehicle and operation control method
CN112470032A (en) * 2019-11-04 2021-03-09 深圳市大疆创新科技有限公司 Topographic prediction method and device for undulating ground, radar, unmanned aerial vehicle and operation control method
CN112558019A (en) * 2020-12-14 2021-03-26 北京遥感设备研究所 Pseudo code modulation-based extra-terrestrial celestial body landing measurement radar transmitting and receiving isolation system

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3121620B1 (en) * 2015-07-21 2017-12-20 HENSOLDT Sensors GmbH Method for segmenting the data of a 3d sensor, produced in the presence of aerosol clouds, for increasing situational awareness and the detection of the position of obstacles
US10514456B2 (en) * 2017-11-29 2019-12-24 Qualcomm Incorporated Radar aided visual inertial odometry outlier removal

Patent Citations (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101960327A (en) * 2008-02-25 2011-01-26 Iad信息自动化及数据处理有限公司 Carry out the apparatus and method that direction is estimated and decoded by means of the secondary radar signal with improvement
CN101493526A (en) * 2008-11-28 2009-07-29 北京工业大学 Lunar vehicle high speed three-dimensional laser imaging radar system and imaging method
CN102384755A (en) * 2010-09-02 2012-03-21 何平 High-accuracy method for measuring instant navigational speed of airborne phased array whether radar
CN102506892A (en) * 2011-11-08 2012-06-20 北京航空航天大学 Configuration method for information fusion of a plurality of optical flow sensors and inertial navigation device
CN102866397A (en) * 2012-10-12 2013-01-09 中国测绘科学研究院 Combined positioning method for multisource heterogeneous remote sensing image
CN105277974A (en) * 2014-07-23 2016-01-27 中国石油化工股份有限公司 Stratum data interpolation method
CN108132461A (en) * 2017-10-13 2018-06-08 西安电子科技大学 Inhibit the method for CW with frequency modulation landing radar direct current leakage
CN108196221A (en) * 2017-12-20 2018-06-22 北京遥感设备研究所 A kind of elimination of burst noise method based on multi-baseline interference instrument direction ambiguity section
CN108802716A (en) * 2017-12-29 2018-11-13 西安电子科技大学 CW with frequency modulation landing radar distance measuring method based on center of gravity correction
CN111381239A (en) * 2018-12-29 2020-07-07 华为技术有限公司 Laser measurement module and laser radar
CN109839623A (en) * 2019-02-14 2019-06-04 北京遥感设备研究所 A kind of objects outside Earth landing instrumentation radar Area Objects echo-signal ranging processing method
CN110095760A (en) * 2019-04-24 2019-08-06 中国气象局气象探测中心 A kind of test device and method of weather radar
CN110261857A (en) * 2019-07-17 2019-09-20 南京信息工程大学 A kind of weather radar spatial interpolation methods
CN110554375A (en) * 2019-08-22 2019-12-10 北京遥感设备研究所 Phased array radar for measuring landing of extraterrestrial celestial body
CN112368663A (en) * 2019-11-04 2021-02-12 深圳市大疆创新科技有限公司 Terrain prediction method and device for sloping field, radar, unmanned aerial vehicle and operation control method
CN112470032A (en) * 2019-11-04 2021-03-09 深圳市大疆创新科技有限公司 Topographic prediction method and device for undulating ground, radar, unmanned aerial vehicle and operation control method
CN111879545A (en) * 2020-09-01 2020-11-03 中国科学院空天信息创新研究院 Ground laboratory remote sensing flight simulation platform and control method
CN112558019A (en) * 2020-12-14 2021-03-26 北京遥感设备研究所 Pseudo code modulation-based extra-terrestrial celestial body landing measurement radar transmitting and receiving isolation system

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Comparisons between multiple in-situ aircraft turbulence measurements and radar in the troposphere;Armin Dehghan;Journal of Atmospheric and Solar-Terrestrial Physics;第64-77页 *
基于单超声传感器的移动机器人沿墙导航;周慧;中国会议;第1-3页 *
多传感器数据融合技术在无人机导航系统的研究应用;禤家裕;中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑;C031-61 *

Also Published As

Publication number Publication date
CN113534066A (en) 2021-10-22

Similar Documents

Publication Publication Date Title
US7969345B2 (en) Fast implementation of a maximum likelihood algorithm for the estimation of target motion parameters
JP4368852B2 (en) Radar equipment
US8884810B2 (en) Compact beacon radar and full ATC services system
US7961147B1 (en) Long baseline phase interferometer ambiguity resolution using frequency differences
EP3494404B1 (en) System and method for detecting heading and velocity of a target object
US20050179579A1 (en) Radar receiver motion compensation system and method
JP2008134256A (en) System and method for central association and tracking in passive coherent location application
JPWO2007015288A1 (en) Axis deviation amount estimation method and axis deviation amount estimation device
CN113009448B (en) Method, device, equipment and storage medium for detecting multipath target
CA2688654C (en) An apparatus for estimating the height at which a target flies over a reflective surface
JP7295317B2 (en) Noise elimination device and method for weather radar
US11249171B2 (en) Method of determining an alignment error of an antenna and vehicle with an antenna and a detection device
CN113534066B (en) Method and system for eliminating landing measurement radar altitude multi-reflection wild value
CN109884337B (en) Method for detecting sea surface wind direction by using high-frequency ground wave radar
US6137439A (en) Continuous wave doppler system with suppression of ground clutter
JP2013152157A (en) Signal selection device, signal selection method, and rader system
KR20180081283A (en) Low power Frequency Modulated Continuous Waveform system and controlling method thereof
US6982668B1 (en) Tangential velocity measurement using interferometric MTI radar
CN110940973B (en) Angle measurement method and device for radar target detection
EP3835822B1 (en) Signal processing device and signal processing method
CN116027288A (en) Method and device for generating data, electronic equipment and storage medium
JP2002071795A (en) Radar device for acquiring and tracking target
CN113687342B (en) Millimeter wave radar real-time ranging method in close-range complex multipath environment
US11879970B2 (en) Signal processing apparatus and signal processing method
CN115372956B (en) Hybrid system radar track starting method based on forward and reverse logic Hough transformation

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