An Enhanced Buffer Management Scheme for Multimedia Traffic in HSDPA

High Speed Downlink Packet Access (HSDPA) enables higher data rate packet switch services over UMTS, creating opportunity to provide a variety of broadband multimedia applications. In HSDPA, buffering of downlink data in the base station (Node B) is required to fulfill the Medium Access Control (MAC) Packet Scheduling functionality. Additionally, flow control over the Iub interface that connects the Node B to the Radio Network Controller (RNC) is standardized in the 3GPP HSDPA technical specifications. Thus, buffer queue management schemes can be conveniently applied to improve downlink traffic QoS performance in HSDPA. Our previous work focused on a novel priority queuing scheme shown to be effective for QoS management of multimedia traffic with concurrent diverse flows towards a HSDPA end user. This paper presents an enhanced scheme that incorporates Iub flow control. A dynamic HSDPA simulator is developed to study the extended scheme, demonstrating the performance improvement achievable.