Research on ad hoc multicast routing algorithm for GSM-R emergency communication

In this paper, a double-mode terminal, which combined GSM-R terminal and MANET functions, is proposed. When natural disaster, terrorist attack or other accident occurs, GSM-R network´s Base Station (BS) may be destroyed, and then the terminal can switch into MANET mode, and take over the emergency task. Meanwhile, an emergency communication system model is established, based on an example of Wuhan-Guangzhou high-speed railway. Voice Group Call Service (VGCS) is widely used in GSM-R emergency communication, but the existing MANET multicast routing protocol can not support VGCS. We propose a new MANET multicast routing protocol called EGCMRP, which is improved from ODMRP. Then, a simulation comparing EGCMRP with ODMRP by ns2 is given. The simulation results show that the EGCMRP has better performance such as delivery ratio, delay and routing load than ODMRP in the proposed model, and meet with the requirement of the application of railway emergency group call.