Study On Joint Power Control Algorithms In The CDMA Uplink System

There are always multi-access interference(MAI) and near-far problem in CDMA communication system.All these will not only induce the decrease of the system capacity but also make the communication quality deteriorate and the serve range reduce ,and so on .In order to overcome the near-far problem at the present time people have manufactured the CDMA receivers with much complex power-control equipment among the mobile users and the bases .So it can realize equal power reception .Presently power control has become a key technology which makes CDMA system feasible . These days people use multiuser detection to combat MAI . If the advantage of power control and multiuser detection combined with each other, a better scheme can be gotten which can resist MAI and near-far problem more effectively ;As is called joint power control .This paper mainly searches for the power control in the CDMA uplink system.The original scheme of the joint power control improved which is according to the standard of MMSE and the channel estimation induced into the system,as makes it own the ability of resisting the variance of the channel;or the play game induced into it,as makes it able to satisfy the need of the communication of all kinds of of target SINR by modulating its system parameters—cost gene and utility gene.Simulation indicates that these algorithms not only are simple to compute but also can control power soon and concisely ,as is very significant for the content of CDMA system.