对流层散射信道下MIMO-OFDM系统性能分析

Performance Analysis of MIMO-OFDM System in Troposcatter Channel

针对对流层散射信道下的通信存在信号微弱和多变的问题,采用MIMO-OFDM技术能够有效解决。论文分析了对流层散射信道的突出特性,建立了散射信道模型;在MIMO-OFDM系统模型基础上,结合实际进行了参数选取,搭建了散射信道下MIMO-OFDM系统实验平台;在验证散射信道下MIMO-OFDM系统性能的基础上,对不同传输速率和不同调制方式在同一散射信道下的系统性能进行了仿真分析。仿真结果表明,MIMO-OFDM在高速率信号传输情况下带来的信道容量的提升是明显的,在满足系统BER要求前提下,能够实现高速率散射通信;在高速率传输时,64QAM调制更加有利于降低散射通信中的BER,而BPSK、QPSK和16QAM调制方式差别不大。该仿真为散射通信设备中多速率多体制调制解调器设计与优化提供了思路,为实现大容量高可靠度散射通信提供了方向指导。

The communication problem of weak and variable signal in troposcatter channel can be effectively solved using MIMO-OFDM technology.This paper analyzes the troposcatter channel characteristics and builds a scattering channel model.Then based on the MIMO-OFDM system model,combined with the ac-tual situation,the parameters are selected and the experimental platform of the MIMO-OFDM system in scattering channel is established.And then under the promise of verification of performance of MIMO-OFDM system,the different transmission rate and different modulation system performance in the same scattering channel are simulated and analyzed.The simulation results show that,the communication capac-ity increase brought by MIMO-OFDM is obvious and on the premise of meeting the BER requirements,it can realize high speed scattering communication.And they also show than in the high speed transmission, 64QAM modulation is more conductive to reduce BER in scatter communication,meanwhile BPSK,QPSK and 1 6QAM modulation have little difference.The simulation provides a way for design and optimization of scattering equipment,which has multi rare and multi modem.It provides direction for the realization of large capacity and high reliability scattering communication.