基于多用户OFDM认知无线电系统中的功率分配算法

ognitive radio is a radio technology which can find free spectrum intellectually and adaptive adjust parameters for transmitting signals. It gives a new way to deal with the shortage of radio resource. OFDM has high spectrum utilization, its flexibly selecting frequency provides a good platform for cognitive radio system. This paper analyze maximizing the system capacity when the interference which main user has is in a limit extension in a multi-user OFDM system. Based on optimal power allocation algorithm, this paper gives a second optimal algorithm which has lower complexity. The simulation compare the two algorithm and with the other second optimal algorithms. The result shows that algorithm in this paper has better performance than the other second optimal algorithms, enlarge the system capacity.