An energy-efficient media access control protocol for chain-type wireless sensor networks

We present in this paper an energy efficient media access control (MAC) protocol for chain-type wireless sensor networks. The chain-type sensor networks are fundamentally different from traditional sensor networks in that the sensor nodes in this class of networks are deployed along narrow and elongated geographical areas and form a chain-type topology. Recently, we have successfully developed hierarchical network architecture, sensor deployment strategy, and corresponding network initialization and operation protocols for this class of sensor networks¹. In this paper, we present a novel TDMA scheduling protocol that takes full advantages of the available channel reuse inherent in the chain-type sensor networks to develop energy efficient and high data throughput MAC protocols for sensor data transmission. The synchronized TDMA scheduling allows the nodes to power on only when it is scheduled to send and receive and therefore results in additional energy saving. Within a cluster, parallel transmission is made possible because of the linear distribution of nodes within the chain-type topology and this yields the desired high throughput. Preliminary simulations have been carried out to show that the proposed TDMA scheduling outperforms the well-known SMAC scheme in terms of energy efficiency and data throughput under various duty cycles.