Improved frequency stepping synthetic aperture radar (SAR) imaging method based on frequency domain frequency spectrum reconstruction

A technology of frequency stepping and imaging method, which is applied in the field of SAR imaging and can solve problems such as distance spectrum aliasing

Inactive Publication Date: 2012-06-27
BEIJING INSTITUTE OF TECHNOLOGYGY
View PDF3 Cites 16 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to address the problem of range spectrum aliasing that may exist in the frequency-stepping SAR imaging method (the second method mentioned in the background technology) th

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
  • Improved frequency stepping synthetic aperture radar (SAR) imaging method based on frequency domain frequency spectrum reconstruction
  • Improved frequency stepping synthetic aperture radar (SAR) imaging method based on frequency domain frequency spectrum reconstruction
  • Improved frequency stepping synthetic aperture radar (SAR) imaging method based on frequency domain frequency spectrum reconstruction

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0035] The present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

[0036] An improved frequency stepped SAR imaging method based on frequency domain spectrum reconstruction. The basic implementation process includes steps one to five, such as figure 1 As shown, specifically:

[0037] Step 1. Simulate the frequency stepped SAR echo data of a point target. The simulation parameters are shown in Table 1. The frequency stepped SAR echo data of the carrier frequency stepped by 4 points are grouped according to the signal carrier frequency to obtain different carrier frequencies 4 groups of sub-band echo data; each group of sub-band echo data contains data of 3500 distance lines.

[0038] Table 1 Simulation parameter table

[0039]

[0040] Step 2. Determine whether the range spectrum of the subband echo data described in step 1 is aliased after two-dimensional focus processing; if spectrum aliasing occurs, expand the range s...

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

An improved frequency stepping synthetic aperture radar (SAR) imaging method based on frequency domain frequency spectrum reconstruction specifically includes: 1 grouping frequency stepping SAR echo data stepping at carrier frequency n points to obtain n groups of sub-band echo data (including data of m distance lines) with different carrier frequencies; 2 judging whether aliasing can happen on distance frequency of the sub-band echo data performed with two-dimensional focus processing, and performing expanding operation on distance frequency spectrum of the sub-band echo data on yes judgment; 3 performing SAR imaging operation on the sub-band echo data, and removing an overlapped part of the frequency spectrum by windowing the distance frequency spectrum in the distance compression process when sub-band echo band width is larger than stepping frequency interval; 4 performing direction registering on n sub-images; and 5 performing distance frequency spectrum reconstruction on data of a kth distance line taken from each sub-image, repeating for m times and obtaining two-dimensional images with high range resolution. The method removes influence of sub-band data distance frequency spectrum aliasing and ensures distance frequency spectrum reconstruction to be performed smoothly.

Description

Technical field [0001] The invention relates to an improved frequency stepped SAR imaging method based on frequency domain spectrum reconstruction, belonging to the technical field of SAR imaging. Background technique [0002] Stepped frequency SAR imaging methods based on frequency domain spectrum reconstruction are mainly divided into two categories: ① first perform range compression and frequency domain spectrum reconstruction, and then perform range migration correction and azimuth focusing processing; ② perform two-dimensional focusing processing first, then do Range frequency spectrum reconstruction. For the first method, the distance compression operation needs to be performed before the distance spectrum reconstruction, but this structure cannot be used in combination with an efficient imaging algorithm—CS algorithm, so its adaptability is worse than the second method. However, the second method has a problem: after the two-dimensional focus processing, the range spectru...

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
IPC IPC(8): G01S13/90G01S7/36
Inventor 田卫明丁泽刚刘荦锶吕争朱动林
Owner BEIJING INSTITUTE OF TECHNOLOGYGY
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap