Distributed fiber sensing technology: Currents and challenges

摘要

In this paper, distributed fiber sensing technologies are explained, showing principles andapplications. Time domain technologies have been developed, at first, as ways to analyze thedistributed information along the fiber. For example, in distributed strain measurement through thenature of Brillouin scattering, basic systems showed limitation in spatial resolution of about 1m.However, novel phenomena and new systems have recently been proposed, and the resolution hasbeen much improved. Optical correlation domain techniques, in which interference of continuouslightwaves is manipulated to obtain the distributed information, have already realized superiorperformances, such as 1.6 mm spatial resolution and 1 kHz sampling rate, in the fiber Brillouindistributed strain sensing. Applications, such as aircraft health monitoring, have also beendemonstrated. Recently, “Brillouin dynamic grating” in a polarization maintaining fiber has beenstudied, and created various novel applications, including simultaneous distributed measurement ofstrain and temperature. With the correlation domain technique, other schemes, such as multiplexingsystems for long‐length FBG distributed sensors, have also been developed.