基于回归算法的OFDM系统帧同步和信道估计研究

Simulation of Frame Synchronization and Channel Estimation Based on Regression Method in OFDM System

提出了一种基于回归方法的联合帧同步和信道估计方案。该方案通过添加在OFDM帧格式中的伪噪声码可以得到帧定时和信道冲击响应,由估计到的信道信息,使频域单抽头均衡器完成信号补偿。仿真结果表明:在瑞利信道下,该方案的帧头丢失率要比滑动平均方案和Beek方案低,并且信噪比大于-10 dB时,帧定时的精确度更高。采用该信道估计方案的均方误差要比LS方案和MMSE方案小。最后比较了采用该方案和传统方案的误码性能。

A joint frame synchronization and channel estimation scheme based on the regression method is proposed. According to an orthogonal frequency division multiplexing （OFDM） frame format by adding the pseudo-noise code, the frame timing and the channel impulse response may be obtained from the proposed scheme. With the estimated channel information, a frequency domain one-tap equalizer is able to achieve the signal compensation. The simulation results show the missing probability of frame starting with the proposed algorithm which performs better than that with the moving average scheme and Beck＇ s scheme in the Rayleigh channel. Also, the frame timing could be exactly obtained with the pro- posed schemes when signal-to-noise raio （SNR） is large than - 10 dB. Besides, the estimator mean square error with the proposed channel estimation scheme is better than that with the least squared （LS） scheme and minimum mean square error （MMSE）scheme. At last, the bit error rate（BER） performance of the proposed scheme is compared with that of traditional method.