基于小波降噪和改进ISFA 的CO-OFDM 信道估计方法

提出了一种基于小波降噪与改进的符号内频域平均(ISFA)联合的相干光正交频分复用(CO-OFDM)系统信道估计方法。该方法利用最小二乘(LS)方法进行信道估计，并对估计后的结果进行小波去噪处理，最后采用Kaiser窗函数改进ISFA 算法对小波处理结果进行ISFA，完成联合去噪。仿真结果表明，该方法可以有效地提高信道估计精度。当光信噪比(OSNR)为17 dB时，该算法的误码性能(BER)比ISFA 算法的误码性能提高将近一个量级。

Abstract

A joint method of coherent optical orthogonal frequency division multiplexing (CO-OFDM) channel estimation based on wavelet denoising and improved intra-symbol frequency domain average (ISFA) is proposed. This method can be divided into three steps. Firstly, channel estimation is performed by least square (LS) method; secondly, the wavelet denoising processing is made for the results of estimation; finally, ISFA algorithm improved by Kaiser- window function is applied to the wavelet processing results. The simulation results show that the proposed method can effectively improve the precision of channel estimation. When the optical signal-tonoise ratio (OSNR) is 17 dB, bit error rate (BER) performance of the proposed method can be improved nearly one order of magnitude than that of ISFA method.

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刘剑飞, 石慧敏, 曾祥烨, 卢嘉, 王蒙军, 刘蓓蕾, 魏春歌. 基于小波降噪和改进ISFA 的CO-OFDM 信道估计方法[J]. 中国激光, 2015, 42(12): 1205002. Liu Jianfei, Shi Huimin, Zeng Xiangye, Lu Jia, Wang Mengjun, Liu Beilei, Wei Chunge. Channel Estimation Method Based on Wavelet and Improved ISFA for CO-OFDM Syetems[J]. Chinese Journal of Lasers, 2015, 42(12): 1205002.

基于小波降噪和改进ISFA 的CO-OFDM 信道估计方法

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