Power control and scheduling for wireless data communications

Abstract

Data traffic will be a major part of the future wireless communication systems. We focus on the power management issues and the information dissemination issues in this thesis. First, we propose a power control algorithm in a DS-CDMA system under multipath environments. The motivation for this study is two fold, limiting interuser interference to increase system throughput and reducing power consumption to prolong battery life. We utilize the delay insensitive property of the data traffic to automatically control the transmit power base on the channel quality through SIR estimation, trying to achieve an optimal trade-off between the transmit power and delay. Simulation results show significant improvement in terms of throughput and power consumption has been achieved, in comparison with other power control algorithms.Second, we propose a new class of scheduling strategies for the data dissemination in mobile networks. We show by analysis and simulation that the network performance depends on both the number of nodes in the network and the number of packets to be disseminated. Our results have showed significant capacity improvement. Our scheduling strategies also achieve higher packet dissemination success probability. Furthermore, we point out that such distributed scheduling is very simple and induces no additional communication overhead to the mobile networks.