A new noise mitigation method based on normalization time frequency peak filtering in broadband power line communication system

摘要

In the power line communication system(PLC), due to the commercial PLC modems feature low power transmission and the large amount of noise, the communication system has a very low signal to noise ratio(SNR) which seriously affects the reliability of the signal transmission. Considering the situation of low SNR, this paper presents a noise mitigation method based on normalization time-frequency peak filtering (NTFPF). NTFPF is a signal enhancement method based on the principle of instantaneous frequency estimation and signal normalization. In NTFPF, the observed noisy signal is firstly normalized and transformed to be processed into instantaneous frequency (IF) of the analysis signal by frequency modulation, and then the peak of time-frequency distribution of analysis signal is taken as the estimation of IF for the concentration of time frequency distribution of analysis signal along with IF. Numerical experiments have shown that the NTFPF method has a good performance in PLC system at low SNR.