SC-FDE系统中基于UW的联合信道估计均衡算法

Joint channel estimation and equalization algorithm based on UW for SC-FDE system

针对基于特殊字(unique word,UW)帧结构的单载波频域均衡(single carrier frequency domain equalization,SC-FDE)系统提出一种联合信道估计噪声预测最小均方误差-残留码间干扰消除(minimum mean square error-residual intersymbol interference cancellation,MMSE-RISIC)均衡算法。该算法包括噪声预测MMSE-RISIC均衡算法与基于UW的噪声消除时域信道估计算法,并将频域均衡算法与信道估计算法相结合。最后,利用华北地区300 km的9径散射链路参数进行仿真,结果表明基于UW的噪声消除时域信道估计算法较基于UW的时域信道估计算法总体性能有所提高,当误码率为10^(-2)时信噪比大约有1.2 dB的性能增益;联合信道估计噪声预测MMSE-RISIC均衡算法相比改进MMSE-RISIC均衡算法性能也有提高,当误码率为10^(-2)时信噪比大约有3.2 dB的性能增益。

A joint channel estimation and equalization algorithm with noise-predictive minimum mean square error-residual intersymbol interference cancellation(MMSE-RISIC)is proposed for single carrier frequency domain equalization(SC-FDE)system with frame structure based on unique word(UW).The algorithm includes noise-predictive MMSE-RISIC equalization algorithm and UW based noise elimination time domain channel estimation algorithm,and combines frequency domain equalization algorithm with channel estimation algorithm.The parameters based on the 300 km troposcatter channel in north China are utilized to make a simulation,the results show that the performance of the noise elimination time-domain channel estimation algorithm based on UW is better than that of the UW based time-domain channel estimation algorithm,when the bit error rate(BER)is 10^(-2),the signal to noise ratio(SNR)has about 1.2 dB performance gain.The noise predictive MMSE-RISIC equalization algorithm has better performance than the improved MMSE-RISIC equalization algorithm and yield SNR gain of about 3.2 dB at BER=10^(-2).