Modelling a Radio Admission Control Scheme for Video Telephony Service in Wireless Networks

摘要

Modern 4G wireless networks are multi-service networks, and an important issue is the development of an optimal radio admission control scheme (RAC) specific to various service types. The 3GPP recommendations for LTE and LTE-Advanced networks specify nine service classes that differ in terms of the priority level, bit-rate, and packet error loss. In this paper, we propose an RAC scheme for video telephony service that is provided in two modes: voice and video. Voice telephony users have a higher priority level than video telephony users; this is realised by the possibility of accepting voice calls owing to the degradation in video call quality. We analyse a model of a single cell with video telephony service, and we prove that the system state space is of an explicit form. This enables us to compute the performance measures, such as blocking probabilities, mean number of calls, and utilization factor.