Joint iterative compressed sensing algorithm eliminating clipping noise in underwater acoustic communication system  

作　　者：WU Jinqiu QIAO Gang ZEESHAN Babar ZHENG Wenting 

机构地区：[1]Science and Techonology on Underwater Acoustic Laboratory of Underwater Acoustic Engineering College,Harbin Engineering University [2]College of Electronic and Communication Engineering,Qiqihar University

出　　处：《Chinese Journal of Acoustics》2017年第4期501-512,共12页声学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(61431004,11304056,6140114,11274079);Education Department of Heilongjiang Province(135209239);Science and Technology Bureau of Qiqihar(GYGG-201622)

摘　　要：Due to the intricacy characteristics of the Underwater Acoustic（UWA） channel especially the limited bandwidth, Orthogonal Frequency Division Multiplexing（OFDM） is used because of its high spectrum efficiency. However, relatively high Peak-to-Average-Power Ratio（PAPR） limits the efficiency of OFDM in UWA communication, leading to saturation in the power amplifier and consequent distortion of the signal. Clipping and C companding as the most classic and convenient algorithms, are widely applied to address the high PAPR issue. However clipping introduces additional noise which degrades the system＇s performance and traditional C companding is also not suitable for underwater acoustic field. Thus, an improved C companding combined with clipping is proposed here. Due to the sparseness of clipping noise, Compressed Sensing（CS） can be utilized to estimate it. The scheme exploits pilot tones and data tones as observations instead of reserve tones, which is different from the previous works and improves data rate. Furthermore, to minimize the effect of the underwater acoustic channel, the channel is also estimated using the CS technique, which provides more accurate channel characteristics than Least Square（LS） or Minimum Mean Square Error（MMSE） estimation algorithms. The effectiveness of the proposed algorithm is proved in computer simulations as well as in a pool experiment.Due to the intricacy characteristics of the Underwater Acoustic（UWA） channel especially the limited bandwidth, Orthogonal Frequency Division Multiplexing（OFDM） is used because of its high spectrum efficiency. However, relatively high Peak-to-Average-Power Ratio（PAPR） limits the efficiency of OFDM in UWA communication, leading to saturation in the power amplifier and consequent distortion of the signal. Clipping and C companding as the most classic and convenient algorithms, are widely applied to address the high PAPR issue. However clipping introduces additional noise which degrades the system＇s performance and traditional C companding is also not suitable for underwater acoustic field. Thus, an improved C companding combined with clipping is proposed here. Due to the sparseness of clipping noise, Compressed Sensing（CS） can be utilized to estimate it. The scheme exploits pilot tones and data tones as observations instead of reserve tones, which is different from the previous works and improves data rate. Furthermore, to minimize the effect of the underwater acoustic channel, the channel is also estimated using the CS technique, which provides more accurate channel characteristics than Least Square（LS） or Minimum Mean Square Error（MMSE） estimation algorithms. The effectiveness of the proposed algorithm is proved in computer simulations as well as in a pool experiment.

关 键 词：UNDERWATER PAPR ITERATIVE CLASSIC SATURATION compressed amplifier eliminating instead utilized 

分 类 号：TN929.3[电子电信—通信与信息系统] TP301.6[电子电信—信息与通信工程]