Resource allocation for multimedia services on the UMTS downlink

Efficient radio resource allocation techniques are vital for providing acceptable capacity over the UMTS Radio Access Network (RAN). Interaction among services and power requirements according to service bit rates can seriously limit the capacity. This work presents a resource allocation framework based on service differentiation and analyzes the capacity benefits achieved through service prioritization and dynamic rate adaptation. Conversational, streaming, interactive and background service classes are considered in the investigation. Real Time (RT) services are offered over dedicated radio access bearers. Non Real Time (NRT) services use downlink shared channels to achieve multiplexing and better resource utilization. Combining prioritized connection admission control based on service class to minimize interference and dynamic rate adaptation for NRT services leads to significant improvements in overall system capacity. Without these capacity enhancement techniques the UMTS downlink can be fairly limited by interference and resource availability in the presence of multiple services operating at various rates and requiring diverse QoS.