Time-division multiplexing is a promising method for the interrogation of fiber-optic Bragg grating sensors arrays for measurement of strain and temperature. We examine the performance of these systems to determine the parameters for high-sensitivity, low-cross-talk operation. It is shown that the performance can be greatly improved by use of a short time resolution in the demultiplexing process. We propose a new method of demultiplexing with an electro-optic modulator to read out the sensor pulses by gating the signal with 400-ps resolution. The system is demonstrated experimentally to provide 0.15−με/√Hz strain resolution in a 50-Hz bandwidth within a full-scale range of 8000 με. The system parameters are capable of handling at least 50 time-addressed sensors on a single fiber.
© 2001 Optical Society of America
[Optical Society of America ]
(060.2370) Fiber optics and optical communications : Fiber optics sensors
(060.4230) Fiber optics and optical communications : Multiplexing
(230.1480) Optical devices : Bragg reflectors
(230.2090) Optical devices : Electro-optical devices
David J. F. Cooper, Trent Coroy, and Peter W. E. Smith, "Time-Division Multiplexing of Large Serial Fiber-Optic Bragg Grating Sensor Arrays," Appl. Opt. 40, 2643-2654 (2001)