A comparison of opportunistic scheduling algorithms for streaming media in high-speed downlink packet access (HSDPA)

High-Speed Downlink Packet Access (HSDPA) is the release 5 extension of WCDMA standard which provides high data rates (up to 10.8 Mbps) by using Adaptive Modulation/Coding (AMC) and fast packet scheduling. This paper presents a comparison of opportunistic scheduling algorithms for streaming media in HSDPA. We first present a discrete event model for HSDPA multimedia system and express stochastic QoS constraints that reflect the requirement for uninterrupted play-out. Next, we present a general structure of the opportunistic scheduling policies which exploit channel and/or buffer content variations for achieving the required QoS. By using computer simulations, we compare the performance of several special cases of the general policy in terms of the maximum number of the users that can be supported with the desired QoS constraint.