CN109444869A - A kind of radar extension target component tunable detector for SLM Signal Label Mismatch - Google Patents

A kind of radar extension target component tunable detector for SLM Signal Label Mismatch Download PDF

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Publication number
CN109444869A
CN109444869A CN201811559480.XA CN201811559480A CN109444869A CN 109444869 A CN109444869 A CN 109444869A CN 201811559480 A CN201811559480 A CN 201811559480A CN 109444869 A CN109444869 A CN 109444869A
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detector
mismatch
detection
radar
signal
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CN109444869B (en
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刘维建
王永良
段克清
张西川
陈威
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Air Force Early Warning Academy
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Air Force Early Warning Academy
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
    • G01S13/04—Systems determining presence of a target
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
    • 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
    • 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
    • G01S7/418—Theoretical aspects
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
    • G01S2013/0236—Special technical features
    • G01S2013/0245—Radar with phased array antenna
    • G01S2013/0254—Active array antenna
    • 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

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

Abstract

The invention discloses a kind of radars for SLM Signal Label Mismatch to extend target component tunable detector.This method is based on multi-channel adaptive and detects thought, introduces adjustable parameter, by adjusting flexible detection of the adjustable parameter realization to mismatch signal.The present invention is primarily based on multichannel phased-array radar system, carries out data receiver using multiple airspace channels, determines data to be tested and training sample data, and form sample covariance matrix using training sample data；Further according to system requirements, adjustable parameter size is determined, and then form Parameter adjustable adaptive detector；The false-alarm probability according to needed for system determines detection threshold；It finally calculates and detection statistic and is compared with thresholding, if being higher than thresholding, adjudicate target presence, it is on the contrary then there is no targets.Compared to traditional detection method, this method can realize robust detection or the inhibition to mismatch signal by adjusting adjustable parameter, have flexible control characteristic；Meanwhile detector itself has CFAR characteristic, there is no need to additional CFAR treatment processes.

Description

A kind of radar extension target component tunable detector for SLM Signal Label Mismatch
Technical field
The present invention relates to a kind of radars for SLM Signal Label Mismatch to extend target component tunable detector, especially suitable for multi-pass Road Connectors for Active Phased Array Radar.
Background technique
Radar is since birth, and function constantly extends and perfect, but target detection is one of most important function always. Due to the limitation of component manufacturing technology level, the radar of early stage often only has single channel, and the target information got is limited, Constrain the performance of radar fighting efficiency.Phased-array radar can be obtained by multiple array element independent transmissions and reception data More information.In addition, multi-channel model can portray the correlation properties of signal between different channels, to be mentioned by signal processing The performance for rising radar system provides possibility.
Tradition and active service advocate war radar be all made of first filtering after constant false alarm (CFAR) handle substep detection method carry out mesh Mark detection, i.e., realize the inhibition of clutter and interference first with matched filtering, letter miscellaneous noise ratio or Signal to Interference plus Noise Ratio is improved, then to matching Filtered output signal carries out CFAR processing, to complete final target detection, determines that target whether there is.Above-mentioned substep inspection Survey method is used to all degree of freedom in systems the design of filter, and filtered data only have one degree of freedom, cannot be into one Step promotes detection performance.Moreover, substep detection needs additional CFAR processing step, processing is relatively complicated, and cost is higher.And from Detection technique is adapted to not using the step independent as one is filtered, is directly examined using data to be tested and training sample data Device design is surveyed, integrated detection method is belonged to.Self-adapting detecting technology has the advantage of multiple protrusions, such as: (1) self-adapting detecting Device usually has CFAR characteristic, does not need additional CFAR processing；(2) self-adapting detecting technology generally has than substep detection technique There is better detection performance；(3) adaptive detector flexible design has multiple design criterias and performance metric available.
With the theoretical promotion with manufacturing process, the resolving power of radar is continuously improved, target echo tend to take up it is multiple away from It from resolution cell, this time point day marks model and is no longer applicable in, and become extending target.In addition, for due to phased-array radar, data Multichannel characteristic while lifting system freedom degree, also bring certain problem, the error between each channel is often led There are mismatches for the steering vector for the number of writing.At this stage for the detection of extension target, and there are multichannels when SLM Signal Label Mismatch Target detection studies deficiency.
Summary of the invention
It is an object of the invention to Solving Multichannel Connectors for Active Phased Array Radar, there are detection extension targets when SLM Signal Label Mismatch Problem.
In order to realize above-mentioned goal of the invention, the present invention provides a kind of radars for SLM Signal Label Mismatch to extend target component Tunable detector design method, including following technical step:
(1) it is based on multichannel phased-array radar system, carries out data receiver using multiple airspace channels；
(2) data to be tested and training sample data are determined, form sample covariance matrix using training sample data；
(3) it according to system requirements, determines adjustable parameter, forms Parameter adjustable adaptive detector；
(4) it calculates and detection statistic and is compared with thresholding, be higher than thresholding, then adjudicate target presence, it is on the contrary then adjudicate There is no targets.
The present invention has the advantages that
(1) the present invention is based on self-adapting detecting thoughts to carry out target detection, compared to traditional substep detection method, has more Good detection performance.
(2) detector that the present invention designs has CFAR characteristic, without additional CFAR treatment process.
(3) detector designed by the present invention can flexibly detect mismatch signal, and reduction adjustable parameter can be realized pair The robust detection of mismatch signal, the inhibition to mismatch signal can be realized by increasing adjustable parameter.
Detailed description of the invention
Fig. 1 is the structural block diagram of the embodiment of the present invention.Sample covariance matrix calculating, quasi- albefaction, detector in figure Etc. treatment processes realization can be programmed on general programmable signal-processing board.
Specific embodiment
It is as follows to implement the principle of the present invention: forming sample covariance matrix, sample covariance matrix pair using training sample Signal guide vector sum data to be tested carry out quasi- albefaction to eliminate clutter, choose reasonable adjustable parameter, form detector Detection statistic determines detection threshold according to preset false-alarm probability value, the detection statistic and detection door of detector Limit is compared, and target is adjudicated if being higher than thresholding and is existed, otherwise target is not present.
Detailed step of the invention is as follows:
(1) the extension target for being K for extended distance dimension, radar echo signal are tieed up matrix with N × K and are expressed as
X=[x1, x2..., xK] (1)
Wherein, the dimensional vector of N × 1Indicate the echo data for the kth distance unit that extension target occupies.
(2) L training sample is utilized, sample covariance matrix is constructed
Wherein, xE, lIndicate first of training sample, subscript ()HIndicate conjugate transposition.
(3) according to system needs, reasonable adjustable parameter γ is chosen.If wishing, detector has steady inspection to mismatch signal Characteristic is surveyed, then needs to meet 0 < γ < 1, and γ is smaller more steady；If wishing, detector has mismatch sensibility to mismatch signal (i.e. inhibition mismatch signal, not using the excessive signal of amount of mismatch as real interested signal), then need to meet γ > 1, and The bigger γ the more steady, but γ should not be too large, and need to meet 1 < γ < 3 of range.
(4) detection statistic as follows is constructed
Wherein, s is signal guide vector, subscript ()-1Representing matrix inversion operation.
(5) detection threshold is determined using Monte Carlo simulation and made decisions, if detection statistic is greater than detection threshold Determine that, there are target, target is not present on the contrary then judgement, Monte Carlo simulation number of run is 100/Pfa, wherein PfaFor system Preset false-alarm probability.
Although the embodiments of the invention are described in conjunction with the attached drawings, but those of ordinary skill in the art can be in appended power Benefit makes various deformations or amendments in the range of requiring.

Claims (3)

1. a kind of radar for SLM Signal Label Mismatch extends target component tunable detector, including following technical step:
(1) it is based on multichannel phased-array radar system, carries out data receiver using multiple airspace channels；
(2) data to be tested and training sample data are determined, form sample covariance matrix using training sample data；
(3) it according to system requirements, determines adjustable parameter, forms Parameter adjustable adaptive detector；
(4) it calculates and detection statistic and is compared with thresholding, be higher than thresholding, then adjudicate target presence, it is on the contrary then adjudicate and do not deposit In target.
2. a kind of radar for SLM Signal Label Mismatch according to claim 1 extends target component tunable detector, feature It is that the radar in step (1) using multichannel phased array system, connects radar echo signal using multiple airspace channels It receives.
3. a kind of radar for SLM Signal Label Mismatch according to claim 1 extends target component tunable detector, feature It is that the detector designed in step (3) includes an adjustable parameter, the value by reducing adjustable parameter can be achieved to believe mismatch Number robust detection, inhibition to mismatch signal can be achieved in the value by increasing adjustable parameter, and the detection statistic of detector is
Wherein, s is signal guide vector,For sample covariance matrix, xE, lFor first of training sample, L is Number of training, X=[x1, x2..., xK] it is data to be tested, K is the extension dimension of target, and non-negative scalar γ is adjustable ginseng Number, subscript ()HFor conjugate transposition, subscript ()-1For matrix inversion operation, if desired robust detection device, then be arranged 0 < γ < 1,1 < γ < 3 is set if needing mismatch sensitive detectors.
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CN110764066A (en) * 2019-08-14 2020-02-07 西安电子科技大学 Target detection method based on real signal subspace under existence of error
CN110988831A (en) * 2019-04-20 2020-04-10 中国人民解放军空军预警学院 Parameter adjustable detector for signal mismatch in clutter and interference coexistence environment
CN111123252A (en) * 2019-12-27 2020-05-08 中国人民解放军空军预警学院 Parameter adjustable direction detection method during signal mismatching in clutter environment
CN111126318A (en) * 2019-12-27 2020-05-08 中国人民解放军空军预警学院 Parameter-adjustable double-subspace signal detection method under signal mismatch
CN112558034A (en) * 2021-02-23 2021-03-26 中国人民解放军空军预警学院 Extended target sensitive detector and system during subspace signal mismatch
CN112558014A (en) * 2021-02-23 2021-03-26 中国人民解放军空军预警学院 Method and system for detecting adjustable subspace of extended target parameters in clutter
CN113030928A (en) * 2021-02-05 2021-06-25 中国人民解放军空军预警学院 Polarization radar extended target self-adaptive detection method and system in non-uniform environment
CN113238211A (en) * 2021-02-05 2021-08-10 中国人民解放军空军预警学院 Parameterized adaptive array signal detection method and system under interference condition

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Publication number Priority date Publication date Assignee Title
CN110988831A (en) * 2019-04-20 2020-04-10 中国人民解放军空军预警学院 Parameter adjustable detector for signal mismatch in clutter and interference coexistence environment
CN110988831B (en) * 2019-04-20 2022-07-01 中国人民解放军空军预警学院 Parameter adjustable detector for signal mismatch in clutter and interference coexistence environment
CN110764066A (en) * 2019-08-14 2020-02-07 西安电子科技大学 Target detection method based on real signal subspace under existence of error
CN110764066B (en) * 2019-08-14 2021-08-13 西安电子科技大学 Target detection method based on real signal subspace under existence of error
CN111123252A (en) * 2019-12-27 2020-05-08 中国人民解放军空军预警学院 Parameter adjustable direction detection method during signal mismatching in clutter environment
CN111126318A (en) * 2019-12-27 2020-05-08 中国人民解放军空军预警学院 Parameter-adjustable double-subspace signal detection method under signal mismatch
CN111123252B (en) * 2019-12-27 2022-04-05 中国人民解放军空军预警学院 Extended target detection method during signal mismatching in clutter environment
CN113030928A (en) * 2021-02-05 2021-06-25 中国人民解放军空军预警学院 Polarization radar extended target self-adaptive detection method and system in non-uniform environment
CN113238211A (en) * 2021-02-05 2021-08-10 中国人民解放军空军预警学院 Parameterized adaptive array signal detection method and system under interference condition
CN113238211B (en) * 2021-02-05 2022-05-10 中国人民解放军空军预警学院 Parameterized adaptive array signal detection method and system under interference condition
CN112558034A (en) * 2021-02-23 2021-03-26 中国人民解放军空军预警学院 Extended target sensitive detector and system during subspace signal mismatch
CN112558014A (en) * 2021-02-23 2021-03-26 中国人民解放军空军预警学院 Method and system for detecting adjustable subspace of extended target parameters in clutter

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