He Chenguang

An Energy-Efficient Message Passing Approach in MAC Design for Wireless Sensor Networks

As wireless sensor networks are used more widely, the design of medium access control protocol will be largely various. The paper reviews Sensor MAC (S-MAC), which is the basic MAC protocol for wireless sensor networks, and points its advantages and disadvantages. Several improving S-MAC protocols that focus on different problems in S-MAC are introduced. The Fragment Indication Message Passing (FIMP), a new energy-efficient message passing approach, is proposed to solve the turnaround consumption problem in S-MAC. It exploits a set of special binary codes to indicate each fragment. Thus, the receiver can easily check the failed fragments. Moreover two ACK packets are used to reduce the possible of retransmission.

An ant colony-based direct communication model routing algorithm for wireless emergency communications system

In this paper, we propose an ant colony-based direct communication model routing (AntDMR) algorithm aimed at wireless emergency communication system. When network infrastructure is destroyed, direct communication mode is employed for guaranteeing system availability. Accordingly, the selection of effective transmission path is a key problem. Considering delay, energy consumption and pheromone track model, the next hop node selection probability function is redefined. Furthermore, the optimal route is achieved. Finally, by comparing with traditional routing algorithm, the performance is impoved more in AntDMR from time-delay and energy-efficiency perspective.