摘要
传统理论认为,当信号以超Nyquist码元速率进行传输,必会引起码间串扰(ISI),误码性能大幅下降。然而1975年Mazo通过理论推导证明,信号在加性高斯白噪声信道下,以超过Nyquist码元速率25%以内的速率进行传输,误码性能可以不下降。本文针对上述理论运用线性最小均方误差均衡(MMSE)和加窗Chase均衡(WCE)两级均衡,在加性高斯白噪声信道下,提出了一种超Nyquist码元速率(FTN)信号的解调接收方案。仿真实验表明在加性高斯白噪声信道下,信号以超过Nyquist码元速率25%以内的速率进行传输,运用本方案进行解调接收误码性能不下降,从而验证了MAZO的理论。
Inter-symbol interference(ISI) will be caused when Faster-Than-Nyquist(FTN) signaling is applied,and it will degrade the system performance according to the traditional communication theory.In 1975,however,Mazo told us that system performance will not be degraded as long as the transmission rate is not beyond 25% faster than the Nyquist rate,because the minimum euclidean distance is not changed though ISI exists.In this paper,a realization scheme in AWGN channel based on two-stage equalization for FTN transmission system is proposed,which is composed of a linear minimum mean square error(MMSE) equalizer followed by a windowed Chase equalizer.Simulation results show that the receive scheme can work normally and keep the BER performance invariable if the transmission rate is not beyond 25% faster than Nyquist,which validates the theory of Mazo through experiment.
出处
《电路与系统学报》
北大核心
2013年第2期119-122,118,共5页
Journal of Circuits and Systems
基金
解放军理工大学预研基金项目(KYTYZLXY1210)