Research On Delay Constratined Energy Efficient Protocols In Wireless Sensor Network

The wireless sensor networks are composed by energy limited sensor nodes which are deployed in monitored region to sense the phenomenon, cooperate each other to send the collected data to sink node. The application of wireless sensor network includes environmental monitoring, disaster management system and target tracking. The sensor node in wireless sensor network has limited energy and is not empowered. Most routing protocols in wireless sensor network treat the energy efficient as their objective without considering the constrained delay and throughput. The paper addresses this issue by introducing two novel routing algorithms.Making the delay less than the constrained value is one of the problems of the new design routing protocols in real-time wireless sensor networks. The DCEA-WFQ and DCEA-WFQ-AGG protocols proposed in this paper can be applied to the networks where the real-time data and non real-time data coexist. The DCEA-WFQ use Weighted Fair Queue packet scheduling model to differentiate services of the real time data and non real-time data. The criteria which the DCEA-WFQ use to select the routing path includes the evaluate energy consumption and the end to end delay bound.The DCEA-WFQ-AGG extends the DCEA-WFQ by introducing the data aggregation scheme which also considers the on-time delivery of delay-constrained data. In DCEA-WFQ-AGG, the most hop path from the source to the sink which is lower than the end to end delay bound is selected and called main path. Other sources connect to the main path via branch path on the relay node where the aggregation occurs. The DCEA-WFQ-AGG is not only energy-efficient but also makes the real-time data's delay within the constrained bound.The simulation experiment proves that in DCEA-WFQ, the real-time delay decreases dramatically and satisfies the need of the real-time application. The simulation experiment also shows that DCEA-WFQ-AGG not only guarantee the real-time's constrained delay but also achieve the decrease of the energy consumption in wireless sensor network.