WCDMA系统下行功率控制方案

Downlink Power Control Schemes in WCDMA

功率控制是WCDMA移动通信系统中提高系统容量和保证链路通信质量的关键技术。传统的下行链路功率控制方案的实现主要存在两个问题:基站发射功率的失衡和下行链路干扰过大。为了解决这两个问题,主要介绍了两种新的下行功率控制方案:站选择分集发射和调整TPC频率功率控制。其中前一种方案用于减小下行链路干扰,后一种方案用于恢复基站发射功率的平衡。研究表明,利用上述方案能够有效减小软切换中继站发射功率的差异以及下行链路干扰,从而提高了系统容量。

Power control is the key technology of WCDMA mobile communication system which can improve the system capability and ensure the communication quality of links. There are mainly two problems in implementing the conventional downlink power control schemes . They are the unbalance of the bases transmitted powers and the increase of downlink interference. In order to overcome these problems, we introduce two new downlink power control schemes ： adjustment TPC frequency power control and site selection diversity transmission power control. Between the schemes, the first one is , used to restore the balance of the bases transmitted power and the second one is used to reduce the downlink interference. It is Shown that the different of the bases transmitted powers of the downlink interference in soft handoff are reduce effectively with these schemes, and thus the system capacity is improved.