Priority-coupling-a semi-persistent MAC scheduling scheme for VoIP traffic on 3G LTE

A fully packet switched access network such as 3G LTE imposes new challenges for real time voice services. Packet drop, delay variation, and random channel fading calls for variations of scheduling technique to address the challenging technical difficulties arising due to the migration from circuit switched domain. A new challenge of starvation comes due to provisioning different services with different delay requirements. This paper proposes a new semi-persistent scheme of MAC scheduling to adaptively prioritize VoIP traffic by not forcing other traffics to starve. The proposed scheme, which combines VoIP priority mode with user coupling, allows to utilize the system capacity efficiently. Simulation shows that the scheme performs better than the original persistent scheduling as well as absolute VoIP priority mode.