Performance Analysis of a Semi-fixed Mapping Scheme for VoIP Services in Wireless OFDMA Systems

Informing users about new resource assignments has to be broadcast, thus generating a substantial amount of the mapping overhead that influences the system throughput. In particular, the performance of voice-over-Internet protocol (VoIP) services is seriously affected by the mapping overhead because the VoIP packet size is small. In order to reduce the mapping overhead, a semi-fixed mapping scheme based on the periodicity of VoIP traffic was introduced. However, up to now, the detailed operation and the analysis of the semi-fixed mapping scheme have not been studied. This paper develops analytical and simulation models and evaluates the performance of a semi-fixed mapping scheme for VoIP services in wireless orthogonal frequency division multiple access systems.