Using Duty Cycle Extension in Time Synchronization and Power Saving

Abstract

Sensor Nodes, as constituents of Wireless Sensor Network, are battery-powered devices and have limited amount of energy available. This limitation must be overcome by using techniques that reduce the consumption of energy effectively. In this article we present a technique called duty cycle extension. It relates to modification of a guard time, and is intended to compensate SN’s quartz frequency instability. In a case when the packet rejection ratio is large, from 40% up to 70%, our intent is to show how duty cycle extension affects both time synchronization, and SN’s battery energy budget. We study how time scales affect duty cycle ratio by varying the time interval between packet transmissions over three orders of magnitude, from 1 s to 3600 s. By implementing this method, an increase of battery capacity from 0.01 % up to 1.406 %, per single year working period, is needed.