一种改进的降低MIMO-OFDM系统峰均比的联合算法*

多输入多输出频分复用(MIMO-OFDM)技术是将OFDM与MIMO技术相结合的无线通信系统,它在继承OFDM与MIMO技术诸多优点的同时,具有OFDM系统存在的峰均比(PAPR)较高的问题。选择性映射法(SLM)和预留子载波保留算法(TR)具有很好地抑制PAPR的性能,但是把传统的TR或SLM方法直接运用到MIMO-OFDM系统中却难以达到很好地抑制PAPR效果。为了寻求在MIMO-OFDM系统中改善PAPR性能的同时降低算法实现复杂度,提出一种TR与SLM算法相结合的适合MIMO-OFDM系统的改进算法TR-SLM。通过理论分析与仿真结果表明,TR-SLM级联算法不仅能有效抑制MIMO-OFDM系统的PAPR,同时可减小算法的计算复杂度与系统实现的复杂度。

Modified united algorithm for reducing PAPR of MIMO-OFDM system

The major drawback of multiple input multiple output orthogonal frequency division multiplexing system (MIMO-OFDM) is its high peak-to-average power ratio (PAPR). Selected mapping (SLM) and tone reservation (TR) has good PAPR reduction performance, but it will be very complicated if the traditional method of TR or SLM is directly applied in MIMO-OFDM systems. In order to solve this problem, this paper proposed an improved TR-SLM method: simple TR algorithm combined the SLM algorithm that the transmission of side information was reduced. The proposed method further reduced the system PAPR, but also significantly reduced the computational complexity of the system. Theoretical analysis and simulation results show that the improved TR-SLM algorithm can effectively suppress PAPR, at the same time it reduce the algorithm complexity and system complexity.