一种降低SFBC MIMO-OFDM系统峰均功率比的新算法

A New PAPR Reduction Algorithm for SFBC MIMO-OFDM System

为了降低SFBC MIMO-OFDM系统的峰均功率比,提出了二次部分传输序列(twice-partial transmit sequence,T-PTS)算法.该算法首先对序列进行相邻分割,再对每一个相邻分割子块进行交织分割,然后对相邻子块和交织子块进行两次相位旋转,从中选择具有最小峰均功率比的序列进行传输,以降低峰均功率比.为简化权值的搜索过程,利用SFBC的编码特性及IFFT的圆周移位特性和共轭特性,对T-PTS算法进行次优化处理,引出RT-PTS(reduced T-PTS)算法,旨在最大程度地降低运算复杂度.仿真结果表明,与传统抑制算法相比,RT-PTS算法可以在降低运算复杂度的同时,取得较好的峰均功率比抑制效果.

A new algorithm named twice-partial transmit sequence（T-PTS） algorithm is proposed to reduce the PAPR of SFBC MIMO-OFDM system.In this algorithm,a transmit sequence is partitioned adjacently,and then every adjacent partitioned subblock is repartitioned in an interlacing way.After rotating both the adjacent and interlaced subblocks twice,a best sequence whose PAPR is minimal is chosen to transmit so as to reduce PAPR.To simplify the search process of weights,a RT-PTS（reduced T-PTS） algorithm,which takes advantage of SFBC in combination with the circular shift and conjugation of IFFT,is proposed to suboptimize the T-PTS algorithm,thus reducing the computation complexity.Simulation results showed that the RT-PTS algorithm can restrict the PAPR effectively at the same time of keeping low computation complexity in comparison with conventional methods.