Adaptive QoS control in HSDPA systems

The high end-user data rates provided by HSDPA makes it a realistic alternative of wired Internet access. New 3GPP releases and the migration to packet based transport are further improving the capabilities of HSDPA. As a result, mobile data traffic is continuously increasing, various packet based services and applications with different QoS requirements are now accessible through HSDPA systems. This evolution requires efficient radio and transport QoS solutions and traffic differentiation methods. The HSDPA QoS framework specified by 3GPP and the air interface packet scheduling disciplines such as PF-RAD enforce the QoS and differentiation per connection level. In contrast, transport QoS architectures such as DiffServ are class based; differentiation is possible only per traffic aggregate level. The different approaches might result in inefficient system operation where the end-to-end QoS can be offered only by reducing the resource usage. This paper proposes a solution that aligns the operation of the transport and radio QoS mechanisms by continuously reconfiguring the transport schedulers. The performance of the proposed solution is investigated with simulations.