Optimal Number of Relays in Cooperative Communication in Wireless Sensor Networks

Wail Mardini,Yaser Khamayseh,Shorouq Al-Eide

doi:10.4236/cn.2012.42014

Abstract

Wireless Sensor Networks (WSN) typically consist of resource constrained micro sensors that organize itself into multihop wireless network. Sensors collect data and send it directly, or through intermediate hops in cooperative communication system, to the collection point. These sensors are powered up by batteries, for which the replacement or recharging is very difficult. With finite energy, we can transmit a finite amount of information. Therefore, minimizing the power consumption for data transmission becomes a most important design consideration for wireless sensor networks. In this paper, we discuss the optimal power consumption in cooperative wireless sensor network that are placed on a grid. We study different cases for the optimal power consumption in such grids by varying the grid distance and number of nodes in the grid. We assume the cases of grids from 2 × 2 up to 5 × 5 in increasing complexity of calculations. The results show that the optimal path that consumes the least power is the path along the diagonal using of the grid when the source and the destination and the furthest two nodes in the grid. This path takes intermediate nodes (relays) along it based on some threshold distances. For example, in 5 × 5 cases; the first threshold between the direct distance and between using one relay in the middle is 31.6 m the second threshold distance is 63.3 m after which using three relays is the best in power consumption between the source and the destination.

Highlights

Due to the tremendous growth in new and innovated wireless technologies that made it cheap and accessible, SN is steered toward wireless domain
Wireless Sensor Networks (WSN) typically consist of resource constrained micro sensors that organize itself into multihop wireless network
Advancements in Global Positions System (GPS), cellular phones, and military applications, highlight the need for self-organized Wireless Sensor Networks (WSN) that can be characterized with optimal characteristics such as shortest route, lowest power consumption, and extended life time

Summary

Introduction

Due to the tremendous growth in new and innovated wireless technologies that made it cheap and accessible, SN is steered toward wireless domain. The accuracy of the result and information obtained by such networks (WSNs) make them preferred by the researchers and the industry. This is due to their close proximity to physical phenomena, ease of deployment, low obtrusiveness and uniform coverage. One of the important features of WSNs nodes is the power consumption since WSNs are usually deployed in remotely or inaccessible sites such as natural habitats, wild fires, and earthquake regions This gives the need to find optimal routing paths and efficient power consumption algorithms for WSNs. WSN can be viewed as data acquisition network which is used to sense natural or man-made phenomena. The lack of easy access to a continuous energy source in most scenarios and the limited lifetime of batteries have hindered the deployment of such network [1,2]

Methods

Discussion

Conclusion