Determining Duty Cycle and Beacon Interval with Energy Efficiency and QoS for Low Traffic IEEE 802.15.4/ZigBee Wireless Sensor Networks

Abstract

Wireless Sensor Networks (WSNs) are becoming integral part of today's world due to their wide range of applications. WSNs are used in industrial applications such as factory automation and control, environmental monitoring etc. which are of low data rate but demand Quality of Service (QoS) in terms of reliability and timeliness along with energy efficiency. A WSN's lifetime depends on the rate of consumption of energy by the sensors. One way to save energy is the judicious use of active and inactive periods in the duty cycle based Medium Access Control (MAC) protocols. The slotted IEEE 802.15.4 MAC protocol provides for it. The duty cycle mechanism however has the potential to affect the performance of the network in terms of QoS due to possible higher packet collision rate in the active periods with reduction in duty cycle. For such applications an appropriate selection of duty cycle that maintains the required QoS is vital while ensuring longevity of the network. Another important MAC parameter that has a role in the performance of WSNs based on IEEE 802.15.4/ ZigBee is the length of the Beacon Interval (BI). In this paper we present the results of our simulation experiments for determining appropriate Duty Cycle and Beacon Interval that maximizes energy efficiency while ensuring the QoS requirements of the application. © Springer International Publishing Switzerland 2014.