Title
Low-power high-accuracy timing systems for efficient duty cycling
Abstract
Time keeping and synchronization are important services for networked and embedded systems. High quality timing information allows embedded network nodes to provide accurate time-stamping, fast localization, efficient duty cycling schedules, and other basic but essential functions - all of which are required for low power operation. In this paper we present a new type of local clock source called Crystal Compensated Crystal based Timer (XCXT) and a number of novel algorithms that effectively utilize it to achieve low power consumption in wireless sensor networks. The XCXT has timing accuracies similar to timers based on temperature compensated crystal oscillators (TCXO) but has a lower implementation cost and requires less power. Our initial 8MHz prototype unit, using the simplest algorithm, achieves an effective frequency stability of ±1.2ppm and consumes only 1.27mW. On the other hand, commercially available TCXOs with similar stability can cost over 10 times as much and consume over 20mW. In addition to the prototype, we will present algorithms that will improve the XCXT's power consumption by at least 48%, depending on application and environmental conditions. We will also show how XCXT's power efficiency can be improved even further by employing clocks at different frequency when different time granularities are required by an application.
Year
DOI
Venue
2008
10.1145/1393921.1393943
ISLPED
Keywords
Field
DocType
oscillator,crystal oscillators,duty cycle,embedded system,emulation,wireless sensor network,synchronization,oscillators,temperature measurement,embedded systems,oscillations,synchronisation,power efficiency,low power electronics,crystals
Electrical efficiency,Synchronization,Crystal oscillator,Computer science,Node (networking),Real-time computing,Electronic engineering,Schedule,Timer,Wireless sensor network,Low-power electronics
Conference
Citations 
PageRank 
References 
9
1.08
3
Authors
5
Name
Order
Citations
PageRank
Thomas Schmid140740.11
Jonathan Friedman258454.98
Zainul Charbiwala315012.93
Young H. Cho430229.05
Mani Srivastava5130521317.38