Date Added: Oct 2012
Improving network lifetime and reliability are the fundamental challenges in Wireless Sensor Networks (WSNs). Most of the research in this area has focused on energy-efficient solutions, but has not thoroughly analyzed the network performance, e.g. in terms of data collection rate and time. A critical aspect of applications with wireless sensor networks is network lifetime. Battery-powered sensors are usable as long as they can communicate captured data to a processing node. Sensing and communications consume energy, therefore judicious power management and scheduling can effectively extend operational time. In this paper, the authors are reviewing some selected techniques or papers which are best describing the lifetime efficiency of the WSN.