Energy-Efficient Opportunistic Transmission Scheduling for Sparse Sensor Networks with Mobile Relays

Wei Liu,Qingtian Ma,Xiaojie Zhao,Xiangjun Dai,Hongjian Guo,Yuan An

doi:10.1155/2016/7024737

Abstract

Wireless sensing devices have been widely used in civilian and military applications over the past decade. In some application scenarios, the sensors are sparsely deployed in the field and are costly or infeasible to have stable communication links for delivering the collected data to the destined server. A possible solution is to utilize the motion of entities that are already present in the environment to provide opportunistic relaying services for sensory data. In this paper, we design and propose a new scheduling scheme that opportunistically schedules data transmissions based on the optimal stopping theory, with a view of minimizing the energy consumption on network probes for data delivery. In fact, by exploiting the stochastic characteristics of the relay motion, we can postpone the communication up to an acceptable time deadline until the best relay is found. Simulation results validate the effectiveness of the derived optimal strategy.

Highlights

In the past decade, wireless sensing technology has attracted much attention from researchers and engineers
We propose an opportunistic transmission scheduling scheme for sparse sensor networks with mobile relays, by means of the optimal stopping approach [12, 13]
This paper studies the problem of finding the optimal time for a sensor node to choose a passing-by mobile relay for data forwarding to minimize the energy consumption on network probes, considering that the relay arrivals reflect the stochastic characteristics of the communication opportunities

Summary

Introduction

Wireless sensing technology has attracted much attention from researchers and engineers. In the case of asteroid belt exploration, the spacecrafts roving in the space can act as messengers to perform this role [7] This solution has already been used in traditional sensor networks, most of previous researches focus on how to control the motion behaviour of Mathematical Problems in Engineering the relay to reduce sensor nodes’ energy consumption [8, 9] or communication delay [10, 11]. These works cannot be directly used in our target applications, where the sensor nodes are mobile [6] or the motion control is costly [7].

System Model

Data Transmission as an Optimal

Performance Evaluation

Conclusion