A node scheduling scheme for energy conservation in large wireless sensor networks

Abstract

In wireless sensor networks that consist of a large number of low‐power, short‐lived, unreliable sensors, one of the main design challenges is to obtain long system lifetime without sacrificing system original performances (sensing coverage and sensing reliability). In this paper, we propose a node‐scheduling scheme, which can reduce system overall energy consumption, therefore increasing system lifetime, by identifying redundant nodes in respect of sensing coverage and then assigning them an off‐duty operation mode that has lower energy consumption than the normal on‐duty one. Our scheme aims to completely preserve original sensing coverage theoretically. Practically, sensing coverage degradation caused by location error, packet loss and node failure is very limited, not more than 1% as shown by our experimental results. In addition, the experimental results illustrate that certain redundancy is still guaranteed after node‐scheduling, which we believe can provide enough sensing reliability in many applications. We implement the proposed scheme in NS‐2 as an extension of the LEACH protocol and compare its energy consumption with the original LEACH. Simulation results exhibit noticeably longer system lifetime after introducing our scheme than before. Copyright © 2003 John Wiley & Sons, Ltd.

Energy management in sensor networks

“…In addition to the aforementioned approach, we can apply other coverage algorithms to select sentries. For example, one can use off-duty eligibility rules [59] to turn nodes off as long as the neighbouring nodes can cover the area for them. We can also adopt a probing mechanism [60] to select sentries.…”

Probabilistic Approach to Provisioning Guaranteed QoS for Distributed Event Detection

“…The length of this timer should be sufficient for sensor nodes to exchange their computed probabilities. After timer tm 2 fires, the refinement procedure commences. Firstly, the sensor node computes a new feasible active probability that takes into account of the contributions from its stakeholders.…”

“…A lot of principles from them can benefit design of energy-efficient sensor networks for event detection. Many algorithms select a subset of sensor nodes to keep vigilant for event detection and put the others in power-save mode for energy conservation, such as PEAS [1], sponsored coverage [2] and differentiated scheduling [3]. They typically aim at providing full coverage in both the spatial and the temporal dimensions.…”

A Case Study on Prototyping Power Management Protocols for Sensor Networks

“…Related work on power management protocols for sensor networks include [7][8][9][10][11][12][13]. In [9], a sensor is allowed to go to sleep if and only if one of its neighbors can completely cover its sensing area. As identified by [7], this approach underestimates the coverage provided by neighboring sensors and, hence, it leads to energy waste.…”

“…Specifically, existing platforms (e.g., nesC/TinyOS [4]) for programming sensor networks use event-driven programming model and, hence, require the designer be responsible for stack management, buffer management, and flow control [5,6]. Therefore, to rapidly prototype and quickly evaluate protocols, the designers of existing power management protocols (e.g., [7][8][9][10][11][12][13]) implement their own simulators or model their protocols in specialized simulators (e.g., GloMoSim [14]). However, it is desirable that the designers prototype their protocols in nesC/TinyOS platform as it provides a framework for generating both simulation as well as production code from the same source.…”