Research On Arq Trasmission Technology In MIMO Wireless Communication System

In the process of transmission,the signal will be affected by the channel environment,which will lead to some errors in the receiving signal.This phenomenon is particularly significant in wireless communication systems.Error is inevitable,but how to reduce the error is the goal of our study.In order to deal with the interference caused by fading,noise and other factors in the transmission,multiple input multiple output(MIMO)and automatic repeat request(ARQ)emerge as the times require.MIMO technology is multi antenna technology,which mainly uses diversity gain and multiplexing gain to improve the reliability of link transmission data and system capacity.Usually,STBC(space division coding)is used in diversity mode,and the V-BLAST structure is used in multiplex mode.ARQ technology is a kind of backward error correction technology,which can bring good time diversity to the system.It is of great significance to improve the transmission reliability of the system.In this paper,we make a theoretical analysis of the compromise relation between diversity and multiplexing mode of the MIMO system by the existing literature.Furthermore,we study the compromise relation between diversity and multiplexing mode of the MIMO ARQ system,which is based on the combination of MIMO technology and ARQ technology,and study the mode switching point of the MIMO ARQ system.Based on the above research,this paper presents an adaptive handover algorithm for MIMO ARQ system in the CSIT scenario.In this paper,the influence of the maximum retransmission times and the maximum packet loss rate on the switching point of the MIMO ARQ system is analyzed.In the MIMO system,precoding technology is a key method to improve the reliability of the system when the transmitter can get perfect or partial channel state information.In this paper,we analyze the gain of MIMO system diversity and multiplexing mode in the different scenarios.Then,when the perfect or partial CSIT is available,the novel MIMO ARQ precoder is proposed to solving the waste power problem in the LTE systems.