Adaptive traffic admission for integrated services in CDMA wireless-access networks

Abstract

Code-division multiple-access (CDMA) is a serious candidate for personal communication systems at 1.9 GHz in North America. We consider the issue of bandwidth management in a CDMA integrated wireless-access network with heterogeneous services. A framework for adaptive connection admission in the up-link direction is proposed. It is based on estimation of the interference at the base station receivers. The estimation algorithm employs a linear Kalman filter which is driven by a measurement of the interference and by predicted traffic parameters of the admitted connections. We derived several generic variants of the control architecture for the up-link direction to assess the main characteristics of the framework and to determine the trade-offs between complexity and performance. They vary from a fixed strategy with fixed power control to an adaptive strategy with full information about network state and adaptive power control. A numerical study of the proposed framework shows that the estimated value of the average interference adapts well to the real value under nonstationary and nonuniform environment. This feature results in high network utilization for arbitrary traffic conditions.