A Dynamic MAC Protocol with Adaptive Power Control for WCDMA Networks

In Wideband code-division multiple-access (WCDMA) systems, all users share the same time and frequency resources and may lead to near far problem, where power control forms an effective solution. A power control algorithm aims to reduce transmission power and interference level, and to maximize system capacity. In this paper, we propose an adaptive power control mechanism for multimedia traffic in WCDMA networks. The proposed algorithm uses two most recent Transmit Power Control (TPC) commands to compute the Adaptive Factor (AF) based on a predefined Adaptive Control Factor (ACF). We introduce another parameter, Power Determining Factor (PDF) based on the data traffic rate to determine the power. Based on this parameter, the power is increased or decreased. Depending on the traffic rate, the PDF factor is updated i.e., if the observed traffic rate is high, then it will increase the parameter and subsequently increases the power and if it is low, then the parameter will be decreased and correspondingly the power also. By simulation results, we show that the proposed power control algorithm reduces the power consumption of multimedia traffic.

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