认知无线网络中功率和信道接入的联合优化

摘要

在认知无线网络中,针对系统中所有用户能否接入同一信道进行通信的问题,提出了适用于不同情形的联合优化方案.在系统不可行的情形下,提出了联合优化功率和接入控制的方案.由于接入控制是NP问题,于是利用所提LP-PSO算法来实现优化控制,并分析和证明了所提算法的收敛性.在系统可行的情形下,提出了联合优化功率和传输速率分配的方案,通过改进拉格朗日对偶(Lagrange duality)算法来实现优化控制.数值结果分析表明,相比其他接入控制算法,虽然所提算法的时间复杂度有所增加但能够快速收敛,在有效地提高接入量的同时还能降低功率消耗,并能使传输速率得到更公平的分配.%In cognitive radio networks,according to the problem of all users can access the same channel to communicate,two joint optimization schemes for different scenarios were proposed.When the system is infeasible,a scheme of joint optimal power and admission control was proposed.As admission control is the NP problem,the LP-SO was used to achieve optimize control.At the same time,the convergence of the proposed algorithm was analyzed and proved.When the system is feasible,a scheme of joint optimal power and transmission rate allocation was proposed,using the improved Lagrange duality algorithm to achieve optimize control.The numerical results show that compared with other admission control algorithms,the time complexity of proposed algorithm is increased,but it can converge quickly,effectively improves the number of admitted uses while reducing power consumption.In addition,the proposed algorithm can allocate transmission rate more fairly.