μs-Scale time synchronization for energy-constrained mission-critical DTSNs
Journal
9th IEEE International Conference on Networked Sensing Systems (INSS 2012)
Date Issued
2012-06
Author(s)
Seng-Yong Lau
Ling-Jyh Chen
Yu-Te Huang
Po-Yen Lin
Yi-Hsuan Chiang
Jyh-How Huang
Kun-chan Lan
Hao-hua Chu
Abstract
It is generally considered a trivial task to synchronize time in a distributed sensor network having a GPS module on board for each sensor node. This is not quite true depending on the application at hand. Commissioned to implement YuShanNet, a delay-tolerant sensor network (DTSN) enabling encounter information collection for hiker search and rescue, we find that the naive use of standard GPSs time acquisition functionalities gives a synchronization error at the scale of 10-100s milliseconds, which is not sufficient given two application-specific considerations: (1) data goodput and (2) energy efficiency. The two requirements are crucial in that the matter is life or death and the hiking trips usually take days. Towards efficient use of the intermittent connectivity in YuShanNet, we design, implement, and evaluate a time synchronization mechanism that improves the synchronization accuracy by approximately two orders of magnitude. This enables TDMA-fashioned MAC for high-goodput data transmission while the GPS is duty-cycled for energy efficiency. © 2012 IEEE.
SDGs
Other Subjects
Delay tolerant; Distributed sensor networks; Energy-constrained; Good put; Information collections; Intermittent connectivity; Orders of magnitude; Search and rescue; Synchronization error; Time synchronization; Data communication systems; Energy efficiency; Sensor networks; Sensor nodes; Sensors; Time division multiple access; Synchronization
Type
conference paper