为了降低MIMO-OFDM (多输入多输出正交频分复用)系统中传统 SLM (选择性映射)算法的计算复杂度，文章提出将原始频域信号分成实部和虚部后分别进行不同的相位旋转，再通过IFFT（快速傅里叶逆变换）调制模块得到相应的时域序列，最后通过多天线间实部和虚部序列的不同组合来产生更多的具有不同PAPR (峰均功率比)的备选序列。仿真结果表明，所提算法能有效地抑制MIMO-OFDM信号的PAPR。相比传统SLM算法能有效降低计算复杂度。

In this paper, we propose a new method to reduce the computational complexity of the conventional Selective Mapping (SLM) algorithm in the Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing(MIMO-OFDM) system. The original frequency domain signals are first divided into real and imaginary parts. Then the two parts are operated by different phase rotation respectively. The corresponding time domain signals are finally obtained by using inverse fast Fourier transform operations. It can produce more candidates with different Peak to Average Power Ratio (PAPR) by different combination of real and imaginary parts in antennas. The simulation results show that the proposed method can reduce the PAPR of MIMO-OFDM signals effectively. In addition, compared with conventional SLM algorithm, the proposed method can reduce the algorithm computation complexity significantly.