A resource allocation scheme for VoIP traffic under high speed train scenario

This paper investigates the resource allocation schemes for Voice over Internet Protocol (VoIP) traffic under high speed train scenario, in which 2-state VoIP traffic model based on Markov chain is considered. Unlike the full-buffer traffic, in which the transmitter buffer is always full of data to be transmitted, VoIP traffic can be characterized by small packets in regular intervals with tight delay constraints. Considering this, two different resource allocation schemes are discussed in this paper. One is an existing scheme adopting fixed Modulation and Coding scheme (MCS) without packet-bundling, which is commonly used for VoIP scheduling in traditional cellular networks; the other one is our proposed scheme, which uses adaptive MCS with packet-bundling and is suitable for broadband wireless communication under high-speed train scenario. System-level simulation is conducted and the simulation results show that the proposed scheme outperforms the conventional resource allocation scheme in terms of the VoIP outage probability and VoIP capacity under high-speed train scenario.