CN114488056B - High-voltage line confirmation method based on broadband Bragg characteristics - Google Patents

High-voltage line confirmation method based on broadband Bragg characteristics Download PDF

Info

Publication number
CN114488056B
CN114488056B CN202111666072.6A CN202111666072A CN114488056B CN 114488056 B CN114488056 B CN 114488056B CN 202111666072 A CN202111666072 A CN 202111666072A CN 114488056 B CN114488056 B CN 114488056B
Authority
CN
China
Prior art keywords
bragg
point
frequency
angle
kth
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
CN202111666072.6A
Other languages
Chinese (zh)
Other versions
CN114488056A (en
Inventor
陈春风
周建江
刘永俊
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.)
Nanjing University of Aeronautics and Astronautics
Original Assignee
Nanjing University of Aeronautics and Astronautics
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 Nanjing University of Aeronautics and Astronautics filed Critical Nanjing University of Aeronautics and Astronautics
Priority to CN202111666072.6A priority Critical patent/CN114488056B/en
Publication of CN114488056A publication Critical patent/CN114488056A/en
Application granted granted Critical
Publication of CN114488056B publication Critical patent/CN114488056B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

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
    • G01S7/41—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
    • 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
    • G01S13/88—Radar or analogous systems specially adapted for specific applications
    • G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
    • G01S13/933—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of aircraft or spacecraft

Landscapes

  • Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Physics & Mathematics (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • General Physics & Mathematics (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Electromagnetism (AREA)
  • Radar Systems Or Details Thereof (AREA)

Abstract

The invention discloses a high-voltage line confirmation method based on broadband Bragg characteristics, which relates to the technical field of radars. The method can be applied to the design of anti-collision radar algorithm of low-altitude flight aircrafts such as helicopters, fixed-wing aircrafts and unmanned aerial vehicles, and can effectively detect high-voltage lines and prevent false alarms.

Description

High-voltage line confirmation method based on broadband Bragg characteristics
Technical Field
The invention relates to the technical field of radars, in particular to a high-voltage line confirmation method based on broadband Bragg characteristics.
Background
According to foreign helicopter accident statistics data, the highest threat to helicopter flight safety is high-voltage lines, and millimeter wave radar is an effective means for detecting the high-voltage lines all weather. The high-voltage wire is an aluminum stranded wire, and the wire diameter of a single aluminum wire is generally 1-4 mm, so that the high-voltage wire has Bragg scattering characteristics in a millimeter wave radar band, and the millimeter wave radar is generally used for detecting the high-voltage wire based on the Bragg characteristics in the millimeter wave band. However, when the conventional method is used in a complex ground environment (such as a densely built area) or an isolated railing, street lamp and other areas between roads, whether the echo is a high-voltage line Bragg echo or clutter of other ground objects is difficult to distinguish, and the problems cause difficulty in associating the high-voltage line, so that the effect of anti-collision radar is greatly affected. In conclusion, the problem that the high-voltage line is difficult to accurately detect in the complex environment exists in the prior art, and particularly the problem that the high-voltage line association of the conventional helicopter millimeter wave anti-collision radar in the complex ground environment is easy to make mistakes and has too many false alarms is solved.
Disclosure of Invention
The invention aims to solve the technical problem of overcoming the defects of the prior art and providing a high-voltage line confirmation method based on broadband Bragg characteristics.
The invention adopts the following technical scheme for solving the technical problems:
the high-voltage line confirmation method based on the broadband Bragg characteristic provided by the invention comprises the following steps of:
step one, angle measurement is carried out on the vertical point position of the echo of the object to be measuredObtaining the vertical point estimation angle of the echo of the object to be detected
Step two, obtaining the estimated angle of the azimuth angle of the kth Bragg point of the echo of the current object to be detectedAnd the angle difference of the kth Bragg point +.>Wherein k=1, 2 …, K is the total number of Bragg points of the echo of the current object to be detected;
step three, adopting the frequency f for the kth Bragg point 1 ,f 2 ,...f m ......f M Angle measurement is carried out, and the frequency f is calculated m Angle difference of kth Bragg point of (2)Frequency f m Angle difference estimate of kth Bragg point +.>Wherein f m The M frequency points are the M-th frequency points, and M is the total number of the frequency points;
step four, calculatingAnd->Mean square error between->If->The kth Bragg point is the true Bragg point, wherein ρ is the Bragg point confirmation threshold;
and fifthly, finishing judgment of all Bragg points of the echo of the current object to be detected to obtain R real Bragg points, and judging that the echo of the object to be detected is a high-voltage line echo and judging that the object to be detected is a high-voltage line if R is more than ζ and ζ is a judgment threshold of the high-voltage line.
As a further optimization scheme of the high-voltage line confirmation method based on the broadband Bragg characteristic, the method comprises the following steps:
the initial frequency of the working carrier frequency of the radar is f 0 At f 0 Obtaining an echo of an object to be detected under the frequency, wherein the echo of the object to be detected comprises azimuth and road data sigma 1 Position difference path data delta 1 ，∑ 1 The sum of the vertical point positions in (a) isΔ 1 The difference value of the vertical point position in (a) is +.>
Firstly, carrying out vertical point and difference angle measurement to obtain a vertical point estimated angle of an echo of an object to be measuredThe formula of (2) is as follows:
wherein, the liquid crystal display device comprises a liquid crystal display device,beam pointing angle K for vertical point of echo of object to be measured a For the antenna difference angle error gain and constant, imag () represents the value of the imaginary part.
As a further optimization scheme of the high-voltage line confirmation method based on the broadband Bragg characteristic, the second step is as follows:
∑ 1 the sum of the kth Bragg points in (a) isΔ 1 The difference value of the kth Bragg point in (2) is +.>For->And->Performing sum and difference measurement to obtain estimated angle of azimuth of kth Bragg point +.>Wherein k=1, 2 …, K is the total number of Bragg points of the echo of the current object to be detected;
wherein, the liquid crystal display device comprises a liquid crystal display device,beam pointing angle for kth Bragg point;
angle difference of kth Bragg pointObtained by calculation of the following formula:
as a further optimization scheme of the high-voltage line confirmation method based on the broadband Bragg characteristic, the third step is as follows:
the frequency f is adopted for the kth Bragg point 1 ,f 2 ,...f m ......f M Angle measurement is carried out, and the frequency f is calculated m Angle difference of (2)Wherein f m The M frequency points are the M-th frequency points, and M is the total number of the frequency points;
calculating the kth Bragg point at the frequency f m Under estimated angle
Wherein, the liquid crystal display device comprises a liquid crystal display device,the representation frequency is f m Sum of kth Bragg point at time, +.>The representation frequency is f m The difference value of the kth Bragg point;
obtained by calculation of the following formula:
frequency f m Under the angle difference estimation valueThe calculation formula is as follows:
as a further optimization scheme of the high-voltage line confirmation method based on the broadband Bragg characteristic, in the fourth step, the high-voltage line confirmation method is calculated according to the formula (7)And->Mean square error between->
Compared with the prior art, the technical scheme provided by the invention has the following technical effects:
(1) According to the invention, the candidate high-voltage line echoes are subjected to multi-frequency radiation to confirm Bragg point characteristics, so that the high-voltage line detection performance of the helicopter anti-collision radar can be greatly improved, and the method has a wide application prospect; aiming at the frequency characteristics of Bragg points, the method fully considers the change relation of Bragg angle and vertical angle difference values under different frequency points, effectively distinguishes clutter from Bragg echo points of real high-voltage lines, and solves the problem of false alarm and error association of the high-voltage lines;
(2) The method can be applied to the design of anti-collision radar algorithm of low-altitude flight aircrafts such as helicopters, fixed-wing aircrafts and unmanned aerial vehicles, and can effectively detect high-voltage lines and prevent false alarms.
Drawings
FIG. 1 is a schematic representation of the Bragg characteristics of a high voltage line at no frequency;
FIG. 2 is a flow chart of an example of an implementation of the present invention;
FIG. 3 is an echo high voltage line and line graph;
FIG. 4 is a graph showing the calculation of the angle difference between different frequency points f1 to f13 and the vertical point;
fig. 5 shows the angle difference between the frequency points f1 to f13 and the vertical point calculated by the radar actual radiation.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.
According to the invention, high-voltage line detection is carried out based on the fact that Bragg scattering azimuth angles of the high-voltage line under different frequency irradiation are different (as shown in figure 1), a mode of measuring a plurality of frequencies is adopted aiming at potential Bragg points of the candidate high-voltage line, and a millimeter wave radar single pulse azimuth angle measurement method is combined, so that Bragg angle change of the candidate high-voltage line is obtained, a real echo of the Bragg point of the high-voltage line is finally identified, error rate of the high-voltage line under complex conditions is reduced, and detection rate of the high-voltage line is improved. Specifically, the method uses a preselected high-voltage line detected by a traditional method, such as a Hough transformation method, as an object to be detected, detects a Bragg point of the high-voltage line of the object to be detected by a conventional CFAR (computational fluid dynamics) method, carries out back-lighting at the Bragg position by a frequency hopping mode, then carries out angle measurement on irradiation echoes with different frequencies, compares angle measurement results with angle expected results of the Bragg point under different frequency conditions, and further judges whether the high-voltage line is a real Bragg point of the high-voltage line, wherein the specific steps are shown in figure 2.
A high-voltage line confirmation method based on broadband Bragg characteristics comprises the following steps:
step one, angle measurement is carried out on the vertical point position of the echo of the object to be measured; the method comprises the following steps:
the example shares the initial frequency f of the working carrier frequency of the radar of the high-voltage line (figure 3) of the object to be detected 0 =93 GHz, at f 0 Obtaining a high-voltage line echo to be detected under the frequency, wherein the high-voltage line echo to be detected comprises azimuth and line data sigma 1 Sum and orientation path data delta 1 ，∑ 1 The sum of the vertical point positions in (a) is(point 3 in FIG. 3), Δ 1 The difference value of the vertical point position in (a) is +.>(point No. 3 in fig. 3);
firstly, carrying out vertical point and difference angle measurement to obtain a vertical point estimated angleCalculated according to equation 1 to obtain->
Step two, estimating the angle difference between Bragg points of the echo of the current object to be detected and the vertical points; the method comprises the following steps:
wherein k=1, 2, 3, 4, the total number of Bragg points of the echo of the current object to be detected is 4 points, and the echo of the first Bragg point isAnd->Calculated according to equation 2, an estimated angle +.>
Wherein, the liquid crystal display device comprises a liquid crystal display device,the beam pointing angle for the radar to strike this Bragg spot is-7.5 DEG, compensated +.>
The angle difference between Bragg point and vertical point of the high voltage lineCalculated by the following formula, 10.1 °:
step three, angle measurement is carried out on the 1 st Bragg point by using different frequencies, and angles under different frequencies are estimated; the method comprises the following steps:
the 1 st Bragg point was calculated by calculating the value of the angle deviation from the vertical point for 13 frequency points of 90GHz,90.5GHz, 93GHz, 96GHzWith a frequency f m Angle difference of +.>Obtain->As a result, as shown in fig. 4, the estimation formula is as follows:
frequency f m Angle difference at the timeObtained by calculation of the following formula:
and the frequency 90GHz,90.5GHz, 93GHz, 96GHzAs shown in fig. 5, the calculation formula is as follows:
step four, calculating according to the formula (7)And->Mean square error between->
Let ρ=0.15, calculatedSatisfy->So the point Bragg point No. 1 is true.
And fifthly, repeating the third step and the fourth step, and similarly calculating 2, 4 and 5 points Bragg to be true to obtain 4 conditions which all meet the fact that the fourth Bragg point is true, wherein ζ=3, R > ζ, and judging the high-voltage line to be true. And (5) judging the true or false of the high-voltage line.
The foregoing is merely illustrative of the present invention, and the present invention is not limited thereto, and any changes or substitutions easily contemplated by those skilled in the art within the scope of the present invention should be included in the scope of the present invention.

Claims (4)

1. The high-voltage line confirmation method based on the broadband Bragg characteristic is characterized by comprising the following steps of:
step one, angle measurement is carried out on the vertical point position of the echo of the object to be measured, and the estimated vertical point angle of the echo of the object to be measured is obtained
Step two, obtaining the estimated angle of the azimuth angle of the kth Bragg point of the echo of the current object to be detectedAnd the angle difference of the kth Bragg point +.>Wherein k=1, 2 …, K is the total number of Bragg points of the echo of the current object to be detected;
step three, adopting the frequency f for the kth Bragg point 1 ,f 2 ,...f m ......f M Angle measurement is carried out, and the frequency f is calculated m Angle difference of kth Bragg point of (2)Frequency f m Angle difference estimate of kth Bragg point +.>Wherein f m The M frequency points are the M-th frequency points, and M is the total number of the frequency points;
step four, calculatingAnd->Mean square error between->If->The kth Bragg point is the true Bragg point, wherein ρ is the Bragg point confirmation threshold;
step five, completing judgment of all Bragg points of the echo of the current object to be detected, obtaining R real Bragg points, and judging that the echo of the object to be detected is a high-voltage line echo and that the object to be detected is a high-voltage line if R is more than ζ and ζ is a judgment threshold of the high-voltage line;
the first step is as follows:
the initial frequency of the working carrier frequency of the radar is f 0 At f 0 Obtaining an echo of an object to be detected under the frequency, wherein the echo of the object to be detected comprises azimuth and road data sigma 1 Position difference path data delta 1 ，∑ 1 The sum of the vertical point positions in (a) isΔ 1 The difference value of the vertical point position in (a) is +.>
Firstly, carrying out vertical point and difference angle measurement to obtain a vertical point estimated angle of an echo of an object to be measuredThe formula of (2) is as follows:
wherein, the liquid crystal display device comprises a liquid crystal display device,beam pointing angle K for vertical point of echo of object to be measured a For the antenna difference angle error gain and constant, imag () represents the value of the imaginary part.
2. The method for confirming a high voltage line based on broadband Bragg characteristics according to claim 1, wherein the second step is as follows:
∑ 1 the sum of the kth Bragg points in (a) isΔ 1 The difference value of the kth Bragg point in (2) is +.>For->And->Performing sum and difference measurement to obtain estimated angle of azimuth of kth Bragg point +.>Wherein k=1, 2 …, K is the total number of Bragg points of the echo of the current object to be detected;
wherein, the liquid crystal display device comprises a liquid crystal display device,beam pointing angle for kth Bragg point;
angle difference of kth Bragg pointObtained by calculation of the following formula:
3. the method for confirming a high voltage line based on broadband Bragg characteristics according to claim 2, wherein the third step is as follows:
the frequency f is adopted for the kth Bragg point 1 ,f 2 ,...f m ......f M Angle measurement is carried out, and the frequency f is calculated m Angle difference of (2)Wherein f m The M frequency points are the M-th frequency points, and M is the total number of the frequency points;
calculating the kth Bragg point at the frequency f m Under estimated angle
Wherein, the liquid crystal display device comprises a liquid crystal display device,the representation frequency is f m Sum of kth Bragg point at time, +.>The representation frequency is f m The difference value of the kth Bragg point;
obtained by calculation of the following formula:
frequency f m Under the angle difference estimation valueThe calculation formula is as follows:
4. the method for confirming a high voltage line based on broadband Bragg characteristics according to claim 3, wherein in the fourth step, the high voltage line is calculated according to formula (7)And->Mean square error between->
CN202111666072.6A 2021-12-31 2021-12-31 High-voltage line confirmation method based on broadband Bragg characteristics Active CN114488056B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111666072.6A CN114488056B (en) 2021-12-31 2021-12-31 High-voltage line confirmation method based on broadband Bragg characteristics

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111666072.6A CN114488056B (en) 2021-12-31 2021-12-31 High-voltage line confirmation method based on broadband Bragg characteristics

Publications (2)

Publication Number Publication Date
CN114488056A CN114488056A (en) 2022-05-13
CN114488056B true CN114488056B (en) 2023-08-01

Family

ID=81508243

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111666072.6A Active CN114488056B (en) 2021-12-31 2021-12-31 High-voltage line confirmation method based on broadband Bragg characteristics

Country Status (1)

Country Link
CN (1) CN114488056B (en)

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102981154A (en) * 2012-12-05 2013-03-20 西安电子工程研究所 Flight track processing method for chain points and whole chain of high voltage wires

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB9822161D0 (en) * 1998-10-12 1998-12-02 Marconi Electronic Syst Ltd Detection of objects
CN106529416A (en) * 2016-10-18 2017-03-22 国网山东省电力公司电力科学研究院 Electric-power line detection method and system based on millimeter wave radar decision tree classification
CN106908791B (en) * 2017-03-03 2020-02-21 中国科学院电子学研究所 Power transmission line extraction method based on full-polarization circular track SAR data
CN107561509B (en) * 2017-08-28 2021-04-30 电子科技大学 Airborne millimeter wave radar power line detection method
CN111695548B (en) * 2020-07-20 2022-12-13 内蒙古工业大学 High-voltage line detection method based on millimeter wave radar
CN112084955B (en) * 2020-09-11 2024-04-05 中国航空工业集团公司雷华电子技术研究所 High-voltage line detection and identification method and device and electronic equipment

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102981154A (en) * 2012-12-05 2013-03-20 西安电子工程研究所 Flight track processing method for chain points and whole chain of high voltage wires

Also Published As

Publication number Publication date
CN114488056A (en) 2022-05-13

Similar Documents

Publication Publication Date Title
US10830874B2 (en) Method to determine the suitability of a radar target as a positional landmark
Ezuma et al. Micro-UAV detection with a low-grazing angle millimeter wave radar
CN107576963B (en) Estimation method of dual-polarization radar differential propagation phase shift based on particle filtering
CN107942305B (en) Online calibration method for initial differential phase of dual-polarization radar system
EP2172789A2 (en) System and method for obstacle detection and warning
US20130328715A1 (en) Millimeter wave radar system for and method of weather detection
US10585172B2 (en) Radar detection method distinguishing rain echoes and radar implementing such a method
CN112068104B (en) Ice crystal identification method and device, electronic equipment and dual-polarization meteorological radar
Lapierre et al. New methods for handling the range dependence of the clutter spectrum in non-sidelooking monostatic STAP radars
CN114488056B (en) High-voltage line confirmation method based on broadband Bragg characteristics
Xia et al. Signal chain architectures for efficient airport surface movement radar video processing
CN110488239B (en) Target detection method based on frequency modulation continuous wave radar
CN109581366B (en) Discrete sidelobe clutter identification method based on target steering vector mismatch
Qin et al. A novel GOSD-CFAR for millimeter wave radar detection
KR102326564B1 (en) System and Method for Correcting Wind Filed of Dual Doppler Radar using Wind Profiler
CN114488145A (en) Image domain DPCA false alarm suppression method based on polarization classification
Kanz et al. Surface Clutter Analysis for Detectability Prediction of Buried Objects with a UAV-Based GPSAR
Ryzhikov et al. Selection of Pulse Repetition Frequency in Radar for Flight Prediction to Detect Flight Trajectories of Small Aircraft and Unmanned Aerial Vehicles at Low Altitudes
CN112068084B (en) Interference echo and ground clutter identification method based on direction spectrum
CN114137539A (en) Method for identifying weather and ground clutter of airborne weather radar
Li et al. Spread E, F layer ionospheric clutter identification in range-Doppler map for HFSWR
Wu Characteristic Parameter Optimization of Wireless Flaw Sensing System Based on Active Interference Suppression Algorithm
Yanovsky et al. Airborne sensor for passive determination of the distance up to lightning source
Guo et al. Forward-looking clutter suppression approach of airborne radar based on ka-jdl algorithm of object filtering
Ohno et al. Automatic target recognition method based on polsar images with circular polarimetric basis conversion

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