The packet-level Reed-Solomon (PRS) code can help to recover burst loss packets for VoIP service over wireless networks. A detailed study on PRS code over a burst loss channel is carried out by means of simulation in this paper.The Gilbert model based on a two-state Markov chain is established for the burst-loss channel. The encoding and decoding algorithms of the PRScode including the truncated code are given. The performance of different PRS codes with three burst-loss channel parameters is obtainedand the relationship between the improved performance and the PRS codes over burst-loss channels is discussed. Based on our study, a method of choosing the suitable PRS codes over burst-loss channel is advised at the end of the paper.

In this paper, we simulate the network running different routing protocols by adding energy module to the node model in the OPNET simulation software. Differences of the network lifetime and end-to-end delay among routing protocols are compared and analyzed. The MPR (multipoint relay) selection mechanism in OLSR (Optimized Link State Routing) leads to rapid consumption of energy of MPR nodes, which cause the OLSR network lifetime to be short. In order to extend the network lifetime, we improve the MPR selection mechanism by taking into consideration node energy when selecting MPR nodes.