Exploiting manufacturing variations for compensating environment-induced clock drift in time synchronization

Time synchronization is an essential service in distributed computing and control systems. It is used to enable tasks such as synchronized data sampling and accurate time-offlight estimation, which can be used to locate nodes. The deviation in nodes' knowledge of time and inter-node resynchronization rate are affected by three sources of time stamping errors: network wireless communication delays, platform hardware and software delays, and environment-dependent frequency drift characteristics of the clock source. The focus of this work is on the last source of error, the clock source, which becomes a bottleneck when either required time accuracy or available energy budget and bandwidth (and thus feasible resynchronization rate) are too stringent. Traditionally, this has required the use of expensive clock sources (such as temperature compensation using precise sensors and calibration models) that are not cost-effective in low-end wireless sensor nodes. Since the frequency of a cr...

• Type: Journal
• Year: 2008
• Where: SIGMETRICS
• Authors: Thomas Schmid, Zainul Charbiwala, Jonathan Friedman, Young H. Cho, Mani B. Srivastava
• Keywords: Clock Sources, Hardware, Inter-node Resynchronization Rate, Resynchronization Rate, SIGMETRICS 2008