An Adaptive MAC Protocol for Mobile Wireless Sensor Networks

In this paper we propose an adaptive MAC Protocol for WSN with mobile nodes, namely RM-MAC (RSSI-Based Mobility Support MAC).The protocol at first uses RSSI to quantify the nodes’ receiving range for the creating of a list of neighboring nodes. Then, it adopts Kalman filter model to predetermine the mobile nodes’ position after a certain period of time. Finally, by referring to the RSSI values and the predetermine position vector, it builds an adaptive model to coordinate dynamically the synchronizing cycle within the virtual clusters so that the clusters can maintain a high connectivity with the mobile nodes. Simulation results shows that compared with S-MAC, RM-MAC can obtain a higher network connectivity and delivery ratio by dynamically coordinating the synchronizing frequency at the cost of some energy. Furthermore, we find that the delivery ratio has close relationship with the quantification level and the cluster switch thresholds.