非正交全双工双向中继系统差错性能分析

摘要

全双工(FD)通信方式能够将双向中继(TWR)系统的频谱效率提高一倍,但是解码可靠性受到残留自干扰的恶化.本文研究非正交FD-TWR系统的差错性能.在中继节点自干扰消除性能强于用户节点的条件下,分析成对差错概率在高发射功率区间的渐进表达式,进而导出系统分集增益和编码增益.针对系统编码结构,分析分集增益的可达条件.与频谱效率相同的半双工TWR系统相比,充分抑制自干扰和采用满分集预编码的FD-TWR系统在误比特率为10 －3时具有20dB的差错性能优势.%The combination of full-duplex(FD)communication and two-way relaying(TWR)provides higher spectral efficiency,but the decoding reliability is worsen by residual self-interference(RSI). The error performance of non-orthogonal FD-TWR is investigated. With the assumption that the relay has more efficient self-interference cancellation than the user nodes,the diversity and coding gains are derived with the help of the approximate expression of pair-wise error probability in the high transmission power region. Based on the coding structure,the achievability of the diversity gain is analyzed. Com-pared with the half-duplex TWR system with the same spectral efficiency,the FD-TWR system with suppressed RSI and full-diversity precoder has the superiority of 20dB on the error performance at the bit error rate of 10 －3.