Open loop correction method for LFMCW SAR nonlinear error

A non-linear error and open-loop correction technology, applied in radio wave measurement systems, instruments, etc., can solve the problems of low calculation and robustness, and achieve the effect of simple implementation, low algorithm calculation and improved signal pulse compression performance
CN104459653AActive Publication Date: 2015-03-25NAT UNIV OF DEFENSE TECH
3 Cites 2 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
NAT UNIV OF DEFENSE TECH
Publication Date
2015-03-25

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention provides an open loop correction method for an LFMCW SAR nonlinear error. According to the technical scheme, an LFMCW SAR VCO signal containing the frequency modulation nonlinear error is collected and subjected to frequency modulation nonlinear analysis, in other words, fitting is performed on all-order error coefficients, the all-order error coefficients having been subjected to fitting are substituted into a frequency modulation nonlinear error correction model, and therefore corrected pre-distortion voltage data can be obtained, and whether pre-distortion voltage is optimal pre-distortion voltage or not can be judged by judging the iteration stopping condition. The correction method is easy to implement, computation burden of an algorithm is low, and pulse compression performance is remarkably improved after correction.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention belongs to the technical field of SAR (Synthesized Aperture Radar, Synthetic Aperture Radar) signal processing, in particular to a method for correcting and processing LFMCW (Linear Frequency Modulated Continuous Wave, Linear Frequency Modulated Continuous Wave) SAR FM nonlinear signals. Background technique

[0002] LFMCW SAR usually uses linear frequency modulation continuous wave as the transmission signal, which is generated by VCO (Voltage Controlled Oscillator, voltage-controlled oscillator), DDS (Direct Digital Synthesizer, direct digital synthesizer) and DAC (Digital-Analog Converter, analog digital conversion) and so on. Compared with linear frequency modulation signal generation methods such as DDS and DAC, VCO has the characteristics of high frequency point, wide bandwidth, and ease of use. However, VCO has the problem of frequency modulation nonlinearity during operation, and the nonlinear error will cause the compressed signa...

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