The Research Of Detection Algorithm For MIMO System

With the continues develop of the socio-economic, the wireless communicationsystem capacity requirements continue to increase,promote the development andappalication of wireless communication systems. Multiple-Input and Multiple-Ouput(MIMO) technology can increase system capacity and spectrum efficiencyexponentially without increase the bandwidth. In the ideal case, the channel capacityof the MIMO system increases linearly with the minimum number between transmitantennas and receiving antennas, which can provide the greatly capacity potentialwhile other technologies can not. Coupled with access to the diversity gain can resistfading channel, which improved the reliability of communication systems greatly.MIMO technique has become one of the main technologies for broadband wirelesscommunication system in the future.Because the transmitter of the MIMO system have many antennas, so for eachantenna of the receiver, the signal received is the superposition of transmit signals,which launched in the present moment by all the transmit antennas. Therefore, how toachieve a higher performance of detection, and the same time have a lowercomplexity of signal detecion has become an issue in MIMO development. For thisproblem, the paper focused on several signal detection menthods based on MIMOtechnology.The content of this paper are listed as follows:1.Analyzing the fading characteristics of the wireless mobile communicationchannel, modeling the MIMO channel using several channel modeling methods, anddeducing the channel capacity expressed by mathematics of MIMO system under flatfading.2.Deep research the general space-time system model and the V-BLAST system,Analyzing and comparing the performance of signal detection for MIMO systemsbased on maximum likelihood, least squares and minimum mean square error and soon traditional detection algorithm, Analyzing the BER performance andcomputational complexity for very detection algorithms, as well as a number offactors affect the bit error rate performance.3.Analysis the basic principles of the sphere decoding algorithm deeply, some derivations and optimizations are made for using in signal detection of the MIMOsystem, and analyze the BER performance and computational complexity.4.Researches on the principle of particle swarm opimization, discreting thetraditional continuous particle swarm optimization algorithms, and will be applied tothe signal detection of MIMO system. In order to prevent falling into local optimum,improving the algorithm and used the improved hybrid discrete binary particle swarmalgorithm applied to the signal detection of MIMO system,analyzing the performanceand computational complexity.The experimental results show that the detection methods which based on spheredecoding algorithm, disrete binary particle swarm optimization algorithm and hybriddiscrete binary particle swarm have a better bit error rate performance, at the sametime, it have a lower computational complexity.