Airborne synthetic aperture radar self-focusing method

A synthetic aperture radar and self-focusing technology, which is applied in the direction of radio wave reflection/re-radiation, utilization of re-radiation, measurement devices, etc., can solve problems such as algorithm failure

Inactive Publication Date: 2017-02-15
SHANGHAI RADIO EQUIP RES INST
View PDF6 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Generally, well-focused SAR images can be obtained by using these algorithms, but when the imaging scene does not match the model assumptions, these algorithms will fail

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Airborne synthetic aperture radar self-focusing method
  • Airborne synthetic aperture radar self-focusing method
  • Airborne synthetic aperture radar self-focusing method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0069] based on the following Figure 1 ~ Figure 3 , specifically explain the preferred embodiment of the present invention.

[0070] Such as figure 1 As shown, the present invention provides an airborne synthetic aperture radar self-focusing method, comprising the following steps:

[0071] Step S1, in the range time domain and azimuth Doppler frequency domain, establish a multi-channel convolution model for the self-focusing problem of airborne synthetic aperture radar;

[0072] Autofocus algorithms usually start with a two-dimensional time domain where the range is compressed but the azimuth is not compressed. In the SAR echo signal, if the range-space variability of the phase error is ignored, the phase error can be considered as a 1-dimensional function that only changes along the azimuth direction;

[0073] Assuming that the 1-dimensional phase error function is φ(m), the data containing the phase error The relationship between and the ideal data s(m,n) can be expres...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to an airborne synthetic aperture radar self-focusing method. According to the method, a channel cross correlation model is established in a noise-ignoring multichannel convolution model, an underdetermined homogeneous linear equation set about the ideal data is acquired, unknown parts exceeding doppler bandwidth partially realize zero setting, a non-zero solution is acquired, frequency spectrum leakage and additive noise are considered, singular value decomposition for a coefficient matrix is carried out, a unique solution under the Euclidean norm is acquired, the ideal data of zero is partially combined with the unique solution, the integral ideal data after recovery is acquired, and azimuth compression for the ideal data is carried out to acquire a focusing image. Through the method, an SAR imaging scene has not any hypothesis, good robustness is realized, the method can be applicable to any SAR imaging scenes, derivation under a theory framework of linear algebra is directly carried out, phase error estimation and compensation without iteration can be carried out to realize focusing of an SAR image, and thereby estimation and compensation of motion errors of the airborne synthetic aperture radar echo data can be effectively realized.

Description

technical field [0001] The invention relates to the technical field of radar signal processing, in particular to an airborne synthetic aperture radar self-focusing method. Background technique [0002] Synthetic Aperture Radar (SAR) is an active two-dimensional high-resolution imaging radar. In the azimuth direction (the direction of platform movement, usually perpendicular to the range direction), the trajectory formed by the relative motion of the target and the radar is used to form a synthetic aperture to replace the huge array of real apertures to obtain high resolution. [0003] Different from spaceborne SAR, due to the influence of atmospheric turbulence and human control, the antenna phase center of airborne SAR always deviates from the ideal uniform linear motion state, so motion compensation must be performed during airborne SAR imaging. So far, SAR motion compensation methods can be divided into two categories: motion compensation methods based on IMU / DGPS (Inert...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01S13/90
CPCG01S13/90G01S13/9019
Inventor 李银伟卢护林盛佳恋魏维伟
Owner SHANGHAI RADIO EQUIP RES INST
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products