基于小波去噪与能量均值的DCT信道估计阈值改进算法  

Improved DCT Channel Estimation Algorithm Based on Wavelet Denoising and Average Energy

作　　者：陈琴[1] 

机构地区：[1]江西理工大学信息工程学院,江西赣州341000

出　　处：《科技广场》2016年第10期4-9,共6页Science Mosaic

基　　金：国家自然科学基金(编号:61363076);江西省自然科学基金(编号:20142BAB207020)

摘　　要：针对DCT的OFDM信道估计传统算法不能有效抑制循环前缀内部噪声的问题,本文介绍了一种基于小波去噪与能量均值的DCT信道估计阈值改进算法。首先,利用小波变换对最小二乘(LS)方法得到的估计结果进行去噪处理,然后求出循环前缀长度内各采样点上的能量均值,并将其作为DCT线性插值过程中的阈值,最后用此阈值对循环前缀内的噪声进行优化,达到降低信道噪声影响的效果。仿真实验表明:在相同的实验环境下,与经典DCT信道估计算法相比,当误码率相同时,改进算法的信噪比大约提高了2dB,当均方误差相同时,改进算法的信噪比大约提高了3dB。Aiming at solving the problem that traditional OFDM channel estimation algorithm based on DCT can not effectively suppress the noise in the cyclic prefix, this paper introduces a new algorithm of DCT channel estimation based on wavelet de-noising and improved threshold. Firstly, the method of LS was used for channel estimation, and then the estimated results was processed through wavelet de-noising; secondly, the average energy of all sampling points within the cyclic prefix was calculated, which is regarded as the threshold in the process of DCT interpolation. Finally, the noise in the cyclic prefix is optimized by the threshold to lower the noise affection on channel. The simu- lation results show that under the same experimental environment, compared with the traditional DCT estimation al- gorithm, the SNR of improved algorithm increases 2 dB when the Bit-Error-Rate is not different, and with the same Mean-Square-Error, the SNR of improved algorithm increases 3 dB.

关 键 词：正交频分复用 DCT信道估计 小波去噪 能量均值 阈值 

分 类 号：TN911[电子电信—通信与信息系统]