Variable bit rate packet data over the WCDMA uplink

Abstract

This paper presents a comprehensive packet data transmission strategy for the WCDMA uplink with quality of service control for multimedia traffic. A centralised admission controller with a noise rise target is used to admit new users into the uplink. A state-based rate scheduler determines the transmission rate to be employed for each schedule period depending on the input buffer size and the channel condition. In addition, the use of a transmission rate variability profile for each user is proposed with a dual purpose. The profile ensures that a user adheres to the carrier to total interference target negotiated during admission though the transmission rate is adapted to match input data rates. Secondly, the profile is used to estimate the spare capacity that would be necessary to provide limited throughput variability to variable bit rate users (VBR). All VBR users share the spare capacity in the system to improve channel utilisation efficiency.