CN-121995358-A - Narrow-band radar super-resolution ranging method based on MTD data

CN121995358ACN 121995358 ACN121995358 ACN 121995358ACN-121995358-A

Abstract

The narrow-band radar super-resolution ranging method based on the MTD data comprises the steps of detecting targets of narrow-band radar received data, recording distance units and Doppler units of an MTD plane where the targets are located, extracting one-dimensional distance image data corresponding to the Doppler units, intercepting data of a preset number of distance units before and after the distance units as super-resolution ranging data, conducting distance grid division on the super-resolution ranging data according to super-resolution multiple, determining a searching range of target distances according to the distance grid division condition and the intercepted number of the distance units, constructing a dictionary matrix corresponding to a set formed by the distance grid points in the searching range, and performing cyclic iteration calculation by using a sparse Bayesian algorithm to obtain a super-resolution ranging result. The method designs a processing flow based on MTD data, extracts data for super-resolution ranging, reduces calculated amount, shortens operation time and improves ranging accuracy based on a quick sparse Bayesian algorithm and combining target type information.

Inventors

MA JIANJUN
Kai Genshen
WANG YONG
YANG GANG

Assignees

西安电子工程研究所

Dates

Publication Date: 20260508
Application Date: 20260324

Claims (7)

1. The narrow-band radar super-resolution ranging method based on the MTD data is characterized by comprising the following steps of: S1, performing target detection on the processed narrowband radar received data, and recording a distance unit and a Doppler unit of an MTD plane where a target is located; s2, extracting one-dimensional range profile data corresponding to a Doppler unit according to the Doppler unit where the target is located; S3, intercepting the data of the distance units with preset numbers before and after the distance units by using the distance units where the targets are located, and taking the data as super-resolution distance measurement data; S4, according to the super-resolution ranging data and the prior information of the target type, performing distance grid division on the super-resolution ranging data according to super-resolution multiples; S5, determining a search range of the target distance according to the distance grid division condition and the intercepted distance unit number, and constructing a dictionary matrix corresponding to a set formed by the distance grid points in the search range; And S6, performing cyclic iterative computation by using the super-resolution ranging data and the dictionary matrix and using a sparse Bayesian algorithm to obtain a super-resolution grid point corresponding amplitude vector, wherein the peak point corresponding distance in the amplitude vector is the super-resolution ranging result.
2. The narrow-band radar super-resolution ranging method based on MTD data according to claim 1, wherein S1 comprises the steps of: s101, pulse compression and target detection preprocessing are carried out on the narrow-band radar received data to obtain MTD plane data; s102, target detection is carried out on the MTD plane data, and after the target is detected, a distance unit and a Doppler unit where the target is located are recorded.
3. The method for super-resolution ranging of a narrowband radar based on MTD data according to claim 1, wherein in S3, the super-resolution ranging data is as follows: Wherein, the In the form of a doppler cell number, Is that Is used for the one-dimensional distance image of (a), For the number of distance units that are screen-shot forward or backward, Is the distance unit number.
4. The method for super-resolution ranging of a narrowband radar based on MTD data according to claim 3, wherein the search range in S5 is: Wherein, the For the resolution of the distance grid, The resolution of the distance is represented by the ratio, Is the super resolution multiple of the distance.
5. The method for super-resolution ranging of a narrow band radar based on MTD data as set forth in claim 4, wherein the dictionary matrix in S5 The column vectors of (2) are expressed as follows: Wherein the dictionary matrix The column vectors of (a) are pulse pressure vectors corresponding to different distance values J is the grid point number.
6. The method for super-resolution ranging of a narrowband radar based on MTD data as recited in claim 5, wherein the target type in S4 refers to a target appearance size.
7. Narrowband radar super-resolution range unit based on MTD data, characterized by comprising: The super-resolution range finding data acquisition module is used for carrying out target detection on the processed narrow-band radar received data and recording a distance unit and a Doppler unit of an MTD plane where a target is located; The super-resolution ranging module is used for carrying out distance grid division on super-resolution ranging data according to super-resolution multiple according to the super-resolution ranging data and prior information of the target type, determining a searching range of the target distance according to the distance grid division condition and the number of intercepted distance units, constructing a dictionary matrix corresponding to a set formed by distance grid points in the searching range, and carrying out cyclic iterative computation by utilizing the super-resolution ranging data and the dictionary matrix through utilizing a sparse Bayesian algorithm to obtain a super-resolution grid point corresponding amplitude vector, wherein the peak point corresponding distance in the amplitude vector is the super-resolution ranging result.

Description

Narrow-band radar super-resolution ranging method based on MTD data Technical Field The invention relates to the technical field of radar ranging, in particular to a narrow-band radar super-resolution ranging method based on MTD data. Background The target-precision distance measurement is a core requirement in the fields of automatic driving, early warning monitoring, topographic mapping and the like, and the range resolution of the radar directly determines the application efficiency of a radar system. The traditional pulse Doppler radar ranging is to realize signal acquisition based on the Nyquist sampling theorem, realize distance measurement through a pulse compression technology, and the distance resolution depends on the time domain main lobe width of a waveform after pulse compression, namely the bandwidth of a transmitted signal. The method for improving the range resolution is characterized in that the bandwidth of a transmitted signal is required to be increased, the bandwidth is increased to obviously improve the data transmission and hardware cost of a radar system, the range resolution is still limited by sampling frequency after the bandwidth is increased, the requirement for high-precision measurement of a target in a complex scene is difficult to solve, and a method for improving the range resolution is required to be searched from the viewpoint of signal processing. In recent years, along with the continuous development of super-resolution theory technology, the super-resolution theory is possible to be applied to the field of high-precision distance measurement, and the idea is that the scattering property of an original target can be recovered from a sparse sample based on the sparse distribution property of strong scattering points of the target in a one-dimensional range profile. To explain its principle, starting from the traditional signal model, it is assumed that the radar transmits a chirp signalThe target is modeled as a point target under narrow-band conditions, but in practice the target is composed ofThe scattering points are formed, and the scattering intensities of the scattering points are different. At this time, the radar receives the target reflected signalThe method comprises the following steps: (1) Wherein, the Represent the firstThe scattering intensity of the individual scattering points,Represent the firstThe propagation delay corresponding to the distance of the individual scattering points,Representing the received noise signal. The echo signal after the conventional pulse compression process can be expressed as: (2) Wherein, the ,Representing the bandwidth of the transmitted signal,Represent the firstPulse pressure post-magnitude at the scattering points. From this expression, it can be seen that when the time delay of each scattering pointThe traditional pulse pressure process cannot distinguish, and different scattering points are compressed into the same distance unit at the same time. When the sampling rate is fixed and the distance unit corresponding to the received data is fixed, the range has inherent error, and the target distance is set asThe distance between the pulse pressure and the sampling point isThen,Representing the corresponding unit size of the current sampling rate, the lower the sampling rate is, the correspondingThe larger the intrinsic error of the ranging is. Aiming at the problem of larger distance measurement error in the traditional pulse compression process, the echo signal after pulse pressure is regarded as a time domain sparse signal, and the pulse pressure signal can be expressed as: (3) Wherein the number of sampling points And only a few scattering points in the target are strong scattering points, and the amplitudes of other scattering points are smaller or tend to be zero, namelyThe number of the larger elements in the method is far smaller than the total number of scattering points。 By utilizing the sparse characteristic of the target scattering points and combining with the sparse theory, the distance parameter solving and converting can be converted into a distance super-resolution solving process: (4) Different sparse solving algorithms can be used for obtaining the super-resolution distance estimation result of the target, however, engineering application is difficult in practical application due to the problems of model adaptation and high algorithm complexity. Accordingly, there is a need to improve one or more problems in the related art as described above. It is noted that this section is intended to provide a background or context for the technical solutions of the present disclosure as set forth in the claims. The description herein is not admitted to be prior art by inclusion in this section. Disclosure of Invention The present invention is directed to a method of super-resolution ranging of a narrowband radar based on MTD data, which, in turn, at least to some extent, overcomes one or more of the problems due to