Blind spot reduction in wavelet transform‐based time–frequency domain reflectometry using Gaussian chirp as mother wavelet. Issue 7 (1st September 2014)

• Record Type: Journal Article
• Authors: Lee, Sin Ho; Park, Jin Bae; Choi, Yoon Ho
• Is Part Of: IET signal processing. Volume 8:Issue 7(2014)
• Page Start: 703
• Page End: 709
• Publication Date: 2014-09-01
• Subjects: blind source separation -- fault location -- Gaussian processes -- time‐domain reflectometry -- wavelet transforms; wavelet transform‐based time‐frequency domain reflectometry -- Gaussian chirp -- mother wavelet -- blind spot reduction method -- WTFDR -- fault localisation -- electric cable -- network cable -- power cable -- overlapped reference signal -- wavelet analysis; Signal processing -- Periodicals; 621.3822
• DOI: 10.1049/iet-spr.2013.0077
• Languages: English
• ISSNs: 1751-9675

Abstract

Abstract : In this study, the authors propose a blind spot reduction method in wavelet transform‐based time–frequency domain reflectometry (WTFDR) by using the Gaussian chirp as the mother wavelet. The blind spot is one of the intrinsic weak points in reflectometry and it means the overlapping ranges of the reference and the reflected signals when the fault is generated at a close distance. Owing to the blind spot, it is difficult to localise the close range fault. Thus, many researchers study the blind spot which is generated in various cables such as electric cable in flight, network cable and power cable. In this study, two methods are used to reduce the blind spot. Firstly, by using the linearity of a complex wavelet transform, the overlapped reference signal at the measured signal is separated and the blind spot is reduced by obtaining the difference of the moduli of the wavelet coefficients for the reference and the reflected signals. Secondly, by using the Gaussian chirp as the mother wavelet, which is designed by considering the characteristics of the cable, the wavelet analysis and the resolution of the WTFDR are improved. Finally, the computer simulations and the real experiments are performed to confirm the effectiveness and the accuracy of the proposed method.