Dynamic Slot Allocation for Improving Traffic Performance in Wireless Sensor Network

Wireless sensor networks have recently received increased attention for a broad array of applications such as surveillance, environment monitoring, medical diagnostics, and industrial control. A wireless sensor network (WSN) contains numerous small sized sensor nodes that have computation power. In WSNs serious incident data collected by the sensor nodes are to be reliably delivered to the sink for successful monitoring of an environment. The battery is the main energy source in the wireless sensor network. For better performance battery power should be sufficient. More energy consumption reduces the lifetime of the wireless sensor network. Also, if the channel utilization is more than throughput of the wireless sensor network reduces. Thus, wireless sensor networks medium access control (MAC) protocols for energy efficiency comes at the cost of extra packet delay and limited throughput, since a sender is allowed to transmit in the short active periods, only. However, typical applications, in addition to low rate periodic traffic, also present burst traffic triggered upon event detections. Therefore, there is an emerging need for a MAC protocol that adapts its offered bandwidth to a dynamic traffic load, i.e., maintain low duty-cycle in light traffic condition and schedule more transmission opportunities when traffic increases so that the energy is only used for carrying the application traffic whenever needed. In this paper we propose a scheme which reduces the traffic in the network using dynamic channel allocation. The duty cycle of the network is also improved.