title: Simple and highly accurate technique for time delay measurement in optical fibers by free-running laser configuration.
abstract: A novel and simple technique for the measurement of time delay in the optical fiber by a free-running laser is proposed and demonstrated. The fiber to be measured was spliced to an erbium-doped fiber so as to form a ring-cavity laser. The mode beating frequency of the laser was measured to determine the round-trip time delay. This precise and efficient technique has an accuracy of 10(-8) for a fiber length of 100 km and of 10(-6) for a several-meters-long one.
authors.affiliation: Institute of Quantum Electronics, School of Electronics Engineering and Computer Science, State Key Laboratory of Advanced Optical Communication Systems and Networks, Peking University, Beijing 100871, China. keyun@stanford.edu
authors.forename: Ke
authors.initials: K
authors.lastname: Yun
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Guangxiao
authors.initials: G
authors.lastname: Zhang
authors.forename: Lingling
authors.initials: L
authors.lastname: Chen
authors.forename: Weijian
authors.initials: W
authors.lastname: Yang
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Zhang