Eztraction of Shaft-rate Modulated Electric Fields of a Ship in Shallow Sea with Strong Background Noise
The electric field is the intrinsic characteristic of a ship. The measurement of the electric field of a ship is greatly disturbed by noise in shallow sea. The measured signals can be processed using wavelet transform, adaptive filtering or time-frequency analysis. Adaptive filtering can be used to remove a part of ambient noise. But the filtering effect is not obvious because a certain type of industrial interference signal is also of an extremely low frequency, When wavelet transform is used to remove noise, most noises from the electric fields of sea are removed. However, it also has nothing to do with the periodical noises with an extremely low frequency. As far as time frequency method is concerned, the original signals are first analyzed within the frequency band, and then they are compared with the measured ambient signals. After the range of shaft-modulated signals are found, the signals of required frequency band are extracted for further IFFT transform. The processing results show that the traffic characteristic of a ship is very clear, representing the signals are extracted out.
ship electric field shaft-rate modulated wavelet transform adaptive filtering time-frequency analysis
Shen Bina Gong Shen-guang Chen Xin-qin Zhang Fan
Dept. of Weaponry Engineering, Naval Univ. of Engineering, Wuhan 430033, ChinaWuhan non-commisioned Dept. of Weaponry Engineering, Naval Univ. of Engineering, Wuhan 430033, China
国际会议
第五届仪器科学与技术国际学术会议(ISIST 2008)Fifth International Symposium on Instrmentation Science and Technology
沈阳
英文
1-7
2008-09-15（万方平台首次上网日期，不代表论文的发表时间）