摘要
超Nyquist码元速率(FTN)理论的出现为提高通信系统数据传输速率奠定了基础。但是,FTN是以引入码间串扰(ISI)为代价的。这给接收端信号检测工作增加了难度。目前已有学者提出了基于线性频域均衡器(FDE)的FTN接收方案。但是FDE在设计抽头系数时没有考虑接收滤波器对信道噪声的影响,而且FDE输出的结果仍然存在残余的ISI,因此性能略差。针对上述问题,将接收滤波器对信道噪声的影响考虑进均衡器设计中,并进一步提出了基于预测型判决反馈均衡器(NPDFE)的FTN接收方案,提高了接收性能。仿真结果表明:在BER=10-4条件下,当ρ=0.8时,NPDFE以提升一倍复杂度的代价使得所需的SNR比FDE减少约5 d B。
The theory of faster-than-Nyquist（FTN） provides the opportunity of increasing data rate at the expense of introducing inter-symbol interference（ISI） ,which increases the degree of difficulty of estimating signals.To solve this problem, a frequency-domain equalizer （FDE）-assisted FTN receiver architecture is provided by a Japanese scholar Shinya Sugiura.However, the equalizer ignores the influence of receiving filter to the noise at the moment of calculating the weights. Furthermore, residual ISI can still be found in the output of the equalizer.So its performance is lower.To address this issue, an improved FDE is provided in the paper,which considers the influence of the receiving filter to the noise. Then, an improved receiving algorithm is proposed, which is based on noise predicted decision feedback equalizer（NPDFE） .The results of simulation show that when the acceleration factor is 0.8 and the number of iteration is 2,the NPDFE requires a SNR 5dB less than the existed FDE to achieve a BER of 10-4 ,although the complexity has to be doubled.
出处
《无线电通信技术》
2016年第5期56-59,63,共5页
Radio Communications Technology
基金
国家自然科学基金项目(61301157)
