Optimal design for digital phase-locked demodulator

被引：0
|
作者：
Li Y. [1 ]
Liu Z. [1 ]
Zhao P. [1 ]
Huo J. [1 ]
Lin Y. [1 ]
机构：
[1] School of Electronic and Information Engineering, Beijing Jiaotong University, Beijing
来源：
Beijing Hangkong Hangtian Daxue Xuebao/Journal of Beijing University of Aeronautics and Astronautics | 2019年 / 45卷 / 02期
基金：
中国国家自然科学基金;
关键词：
Anti-noise; Digital phase-locked demodulator; Dynamic tracking; Electromagnetic non-destructive testing; Kalman filter;
D O I：
10.13700/j.bh.1001-5965.2018.0296
中图分类号：
学科分类号：
摘要：
Digital phase-locked demodulator is an important method for weak signal processing in electromagnetic non-destructive testing. For its performance optimization, a digital phase-locked demodulator with Kalman filter is designed, which has strong anti-noise ability and good dynamic tracking features. By using the characteristic that the cut-off frequency of Kalman low-pass filter decreases with the number of iterations and combining with the zero frequency, we design a low-pass filter in a digital phase-locked demodulator and then realize very narrow phase-locked bandpass, which improves the ability of strong noise resistance. In addition, using the predictive-update feature of the Kalman filter, the smaller response time of the digital phase-locked demodulator is realized, thereby improving the dynamic tracking characteristics of the digital phase-locked demodulator. Simulation and detection experiments show that the designed digital phase-locked demodulator has high noise immunity and good dynamic tracking response. It can accurately and quickly capture the defect information contained in the detection signal in electromagnetic non-destructive testing. © 2019, Editorial Board of JBUAA. All right reserved.
引用
收藏
页码：299 / 308
页数：9
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