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CN-116774161-B - Method for estimating multipath delay section under dense false target interference background

CN116774161BCN 116774161 BCN116774161 BCN 116774161BCN-116774161-B

Abstract

The invention discloses a method for estimating multipath delay sections under a dense false target interference background, which comprises the steps of obtaining a first data vector X 'and a second data vector Y' based on target echo signals received by a main antenna and an auxiliary antenna, obtaining a first distance unit vector U based on the first data vector X ', obtaining a second distance unit vector V based on the second data vector Y', and obtaining the number of delay distance units of multipath interference to be estimated relative to direct interference based on the first distance unit vector U and the second distance unit vector V. The invention has simpler realization and more convenient processing process, can avoid a large number of multiplication operations, reduce the calculated amount, accelerate the operation speed and save the storage resources.

Inventors

  • ZHAO YONGBO
  • Ma Wendan

Assignees

  • 西安电子科技大学

Dates

Publication Date
20260512
Application Date
20230511

Claims (9)

  1. 1.A method for estimating multipath delay profile in a dense false target interference context, the method comprising: Based on target echo signals received by a main antenna and an auxiliary antenna, a first data vector corresponding to the main antenna is obtained A second data vector corresponding to the auxiliary antenna ; Based on the first data vector Obtaining first distance units corresponding to all detection threshold elements in the target echo signals received by the main antenna, wherein all the first distance units form a first distance unit vector ; Based on the second data vector Obtaining second distance units corresponding to all over-detection threshold elements in the target echo signals received by the auxiliary antenna, wherein all the second distance units form a second distance unit vector ; Based on the first distance element vector And the second distance element vector Obtaining the number of delay distance units of multipath interference to be estimated relative to direct interference; comprising the steps of 1) vectorizing said first distance unit Each first distance unit of the plurality of first distance units subtracts the number of the current delay distance units Obtaining a third distance unit vector 2) According to the third distance unit vector And the second distance element vector The number of the same distance units is obtained 3) Judging Whether it is true or not, If the number of the maximum delay distance units is the set number, executing the step 4), otherwise, making Returning to the step 1) until 4) Obtaining the curve finally Determining the said According to the maximum value corresponding to the maximum value And obtaining the number of delay distance units of the multipath interference to be estimated relative to the direct interference.
  2. 2. The method for estimating multipath delay profile in dense false target interference context according to claim 1 wherein a first data vector corresponding to a main antenna is obtained based on target echo signals received by the main antenna and an auxiliary antenna A second data vector corresponding to the auxiliary antenna Comprising: Obtaining a first signal vector corresponding to the main antenna based on target echo signals received by the main antenna and the auxiliary antenna A second signal vector corresponding to the auxiliary antenna ; Based on the first signal vector And the second signal vector Obtaining a first data vector corresponding to the main antenna A second data vector corresponding to the auxiliary antenna 。
  3. 3. The method for estimating multipath delay profile in dense false target interference context according to claim 2, wherein a first signal vector corresponding to said main antenna is obtained based on target echo signals received by said main antenna and said auxiliary antenna A second signal vector corresponding to the auxiliary antenna Comprising: performing pulse compression processing on the target echo signal received by the main antenna to obtain the first signal vector Performing pulse compression processing on the target echo signal received by the auxiliary antenna to obtain the second signal vector 。
  4. 4. The method of estimating multipath delay profile in a dense decoy interference context of claim 2, wherein the first signal vector is based on And the second signal vector Obtaining a first data vector corresponding to the main antenna A second data vector corresponding to the auxiliary antenna Comprising: For the first signal vector Square law detection or linear detection is carried out to obtain the first data vector For the second signal vector Square law detection or linear detection processing is carried out to obtain the second data vector 。
  5. 5. The method of estimating multipath delay profile in the context of dense decoy interference according to claim 2, characterized in that it is based on said first data vector Obtaining first distance units corresponding to all detection threshold elements in the target echo signals received by the main antenna, wherein all the first distance units form a first distance unit vector Comprising: For the first data vector Performing constant false alarm detection processing to obtain the first data vector All the first distance units corresponding to all the over-detection threshold elements form a first distance unit vector 。
  6. 6. The method of estimating multipath delay profile in the context of dense decoy interference according to claim 2, characterized in that it is based on said second data vector Obtaining second distance units corresponding to all over-detection threshold elements in the target echo signals received by the auxiliary antenna, wherein all the second distance units form a second distance unit vector Comprising: For the second data vector Performing constant false alarm detection processing to obtain the second data vector A second distance unit corresponding to all the over-detection threshold elements, wherein all the second distance units form a second distance unit vector 。
  7. 7. The method of estimating multipath delay profile in the context of dense decoy interference according to claim 1 wherein the third range bin vector The calculation formula of (2) is as follows: Wherein, the Representing the i-th first distance element, 。
  8. 8. The method for estimating multipath delay profile in the context of dense decoy interference according to claim 1, wherein said step 2) comprises: Counting the number of vectors existing in the third distance unit And is present in the second distance element vector The number of distance units in the graph is obtained 。
  9. 9. The method of estimating multipath delay profile in the context of dense decoy interference according to claim 1, wherein the profile Expressed as: Wherein, the Representing the number of elements of the finite set, Representing taking the intersection.

Description

Method for estimating multipath delay section under dense false target interference background Technical Field The invention belongs to the technical field of radars, and particularly relates to a method for estimating multipath delay sections under a dense false target interference background. Background Dense decoy interference is one of common deception interference signals, and because the interference signals have stronger coherence with radar echo signals, the interference signals can generate relatively high pulse compression gain after matched filtering processing, namely a plurality of false peaks appear. In general, the power of the interference signal is greater than that of the radar echo signal, so that a plurality of false peaks are mixed with the real target, so that the detection performance of the radar is reduced, and the real target and the deceptive false target cannot be identified after the radar antenna receives the target echo. Side lobe concealment (English holly: sidelobe Blanking, english abbreviation: SLB) is widely used as a common anti-interference technology because of its simplicity and good anti-interference effect. The side lobe shadow hiding technology is an effective method for inhibiting deception interference such as false targets entering from antenna side lobes, and is realized by utilizing an auxiliary antenna to simultaneously receive signals with a main antenna, then carrying out the same processing such as pulse compression, detection, constant false alarm detection and the like on the signals received by the radar main antenna and the auxiliary antenna, comparing two paths of processing results based on corresponding distance units, and then carrying out shadow hiding judgment on the comparison result so as to make a decision on whether the main antenna signal passes or not, thereby achieving the purposes of eliminating radar interference signals and retaining target signals. The performance of side-lobe concealment techniques is related to the multipath effects of the signal in propagation. In the process of propagation of electromagnetic waves, due to reflection or scattering of the ground or a building, a plurality of paths appear in propagation, and the time for the electromagnetic waves of each path to reach a radar receiver is different, so that multipath effect is generated. The interference of the interference signal sent from the interference source and received by the radar antenna is direct interference, and the multipath interference is the interference of the direct interference received by the radar antenna after being reflected or scattered. Due to the difference of propagation mediums of signals in the propagation process, the loss of interference signals can be different, and the amplitude of signals received by the radar antenna is different. Therefore, the multipath effect causes the direct interference and the multipath interference to be different in the pulse distance unit position and strength, i.e. the multipath interference has a time delay relative to the direct interference. The side lobe shadow hiding technology is an effective method for inhibiting deceptive interference such as false targets entering from antenna side lobes, but under the condition of multipath effect, weak multipath interference signals are possibly received by a main antenna main lobe, so that the side lobe shadow hiding technology cannot completely eliminate false target interference, and further the radar cannot accurately detect a real target. In the prior art, the multipath interference is eliminated by firstly calculating the number of delay sections of the multipath interference relative to the direct interference through the estimation of the cross-correlation function of interference signals of a main channel and an auxiliary channel, then adding the delay sections in the auxiliary channel, and carrying out the combined side lobe shadow hiding processing, so that the multipath interference inhibition capability is improved, but when the delay sections are estimated by using the cross-correlation function method, a large amount of multiplication operations are required in an actual system, and a large amount of storage space is occupied. Disclosure of Invention In order to solve the problems in the prior art, the invention provides a method for estimating a multipath delay section under a dense false target interference background, which can directly estimate a time delay section between multipath interference and direct interference when a side lobe shadow technique is used for suppressing dense false target interference under a multipath environment. The technical problems to be solved by the invention are realized by the following technical scheme: A method of estimating multipath delay profile in a dense false target interference context, the method comprising: based on target echo signals received by a main antenna and an auxiliary antenna, a first data