Performance Analysis of VoIP Services in the IEEE 802.16e OFDMA System With Inband Signaling

Although the voice over Internet protocol (VoIP) service is expected to be widely supported in wireless mobile networks, the feasibility and capacity of the protocol have not previously been studied in relation to the emerging IEEE 802.16e orthogonal frequency-division multiple access (OFDMA) system. Informing subscriber stations about new downlink or uplink resource assignments creates a signaling overhead that influences the system throughput. In particular, the performance of VoIP services is seriously affected by the signaling overhead because the symmetry between the downlink and uplink causes immense downlink overheads. However, previous research on the IEEE 802.16e OFDMA system has not taken the signaling overhead into consideration. In the analytical model presented here, the signaling overhead is considered in the evaluation of the uplink and downlink performance of VoIP services in the IEEE 802.16e OFDMA system.