| In modern communication system,carrier communication is a kind of communication mode based on physical transmission network for signal transmission,which has the advantages of low cost and strong reliability.According to the voltage strength of power line,the carrier communication can be divided into three types:high-voltage carrier communication,medium voltage carrier communication and low voltage carrier communication.Compared with the other two kinds of carrier communication,the medium voltage carrier channel has the characteristics of high noise,large impedance,complex node and severe attenuation,which leads to the signal attenuation and noise interference in the process of medium voltage channel transmission,therefore,how to effectively suppress the medium voltage carrier signal is particularly important-Combined with the above background,in this paper,an improved algorithm is proposed,which combines wavelet packet algorithm and ICA algorithm to study the denoising of medium voltage carrier signal.The concrete idea is:Firstly,find the optimal threshold and the optimal basis of the wavelet packet algorithm,then use the improved wavelet packet algorithm to decompose the acquired medium voltage carrier signal to obtain the medium voltage carrier signal separated in each frequency band.Secondly,use the ICA algorithm to separate the matrix of frequency signal;Finally,use the modified wavelet packet algorithm to reconstruct the separated signal and realize the effective denoising of the medium voltage carrier signal.The experimental results shows:compared with the single wavelet packet algorithm,the improved wavelet packet ICA algorithm proposed in this paper can effectively improve the signal-to-noise ratio and denoising effect in the application of medium voltage carrier signal denoising. |
