Application of Modified Particle Swarm Optimization Algorithms to Multi-user Detection in Uplink MIMO-OFDM Systems

• Main Authors: Yi-Ruei Juang, 莊佾叡
• Other Authors: 譚旦旭
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/dt8zeh

碩士 === 國立臺北科技大學 === 電機工程系所 === 97 === This study applies modified particle swarm optimization (PSO) algorithms to MIMO-OFDM uplink systems for multiuser detection. Multiuser interference (MUI) is a major factor that degrades system performance. To overcome this problem, optimal multiuser detector (OMD) is recognized as the best solution, but its computational complexity is too high to be implemented for practical applications. To achieve a best compromise between system performance and complexity, many suboptimal detectors, such as genetic algorithm-based multiuser detector (GA-based MUD), have been proposed. However, experimental result reveals that the performance and convergence speed of GA-based detector are still not acceptable. This study replaces GA with PSO algorithm, and use MMSE receiver to generate initial values for PSO. Furthermore, we combine various mutation schemes which are fixed mutation (FM_PSO), non-fixed mutation (NFM_PSO) and simulated annealing (SA), to increase the population diversity for better solution. Experimental result indicates that the performances of PSO algorithm combining mutation schemes are better than that of conventional PSO and GA-based schemes, and SA_PSO-MUD is among the best one.