Energy efficient analysis with end-to-end delay constraints in wireless sensor networks

Longer time sleep (low duty cycle) of sensor nodes with sleep-wake mechanism in wireless sensor networks will result in longer delay for transmitting of data-collected, although it can reduce node's energy consumption and extend node's lifetime. Therefore, it is an important and significant topic to balance energy consumption and delay in wireless sensor networks. In this paper, we mainly focus on energy efficient mechanism with end-to-end delay constraints. We divide input flows into multiple sub-flows in terms of a configurable weight of links in order to avoid excessive energy consumption of sensor nodes caused by forwarding too much data-collected. So, data-collected pass through multiple different links and sensor nodes to reach the sink node. We establish an analytic framework for end-to-end delay based on network calculus according to arrival process of flows and service process of sensor nodes. On the other hand, sensor nodes provide rate-latency guaranteed service for arrival flow based on their active time and the maximum capacity of links. The case study and numerical results show that the proposed method can provide an effectively balanced strategy between energy consumption and delay by adjusting the duty cycle of sensor nodes properly in wireless sensor networks.