Extended-rtPS+ Considering Characteristics of VoIP Codecs in Mobile WiMAX

We review previous resource allocation algorithms for voice over IP (VoIP) services in Mobile WiMAX based on the IEEE 802.16e-2005 standard, and propose a new algorithm that allocates radio resources in the consideration of packet-size and packet-generation period variations of wireless VoIP codecs; hence, we can improve the efficiency of resource utilization in Mobile WiMAX. Through simulations, we demonstrate the outstanding performance of our proposed algorithm with respect to packet dropping probability and VolP capacity for various VolP codecs, such as adaptive multi-rate wideband (AMR-WB) codec, enhanced variable rate codec (EVRC), and G.729B codec. In addition, we compare VolP capacity of each algorithm according to the application of VolP header compression schemes, such as payload header suppression (PHS) and robust header compression (ROHC).