Wireless packet scheduling in an integrated CDMA system using channel status information

Abstract

A fair queueing algorithm is proposed for data services in an integrated voice/data code-division multiple access (CDMA) system. After delay-sensitive voice users are allocated first, residual resources are allocated to data users according to the throughput maximization strategy. In order to fairly allocate data users, we use power resource concept which considers the BER and the rate requirement of data users, and apply weighted fair queueing (WFQ) to CDMA systems with consideration of a generalized processor sharing fluid-flow model. In order to implement this fair resource allocation scheme, a virtual clock for short-term fairness and a credit table method for long-term fairness are used. Based on these concepts, we propose weighted fair queueing with state control. This scheme allocates resources in the consideration of each channel state. When this scheme is applied to wireless channels, the throughput and delay of data services are shown. Numerical results show that the throughput of each data user has the same characteristics under wireless channel conditions. The throughput of data users can also be increased compared with a conventional WFQ scheme because available resources for data users in bad state are used by other users in good state. (C) 2004 Elsevier B.V. All rights reserved.