Circular-layer algorithm for ad hoc sensor networks to balance power consumption

Abstract

In senor networks, the data traffic from the sensors are directional towards a data sink and are therefore uneven. The areas nearer the data sink experience higher data traffic and will run out of energy sooner. Circular-layer geometry takes into account the radial data traffic towards the data sink. We may construct an algorithm to divide the network into equal-area circular-layers, which are analogous to the square design in geographical adaptive fidelity (GAF). However, the circular-layer geometry alone has not taken into account the uneven data traffic. This paper proposes a circular-layer algorithm that schedules the sensors into active and sleep states in such a way as to evenly distribute the power consumption throughout the sensor networks. We divide the network into circular layers with the data sink at the center. The algorithm equalizes the lifetime time of all layers so that the nodes near the data sink will not run out of energy sooner. Energy is also wasted in reactive routing where the sensors flood the network with omni-directional route discovery messages to find a suitable route towards the data sink. This algorithm reduces such flooding by directing the route request messages towards the data sink, resulting in more energy saving. The circular-layer geometry alone is serving to save energy. In addition, balancing the power consumption throughout the network yields an additional lifetime extension of 21% in our simulation results of a four-layer scenario.