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Recently, Bragg grating fibers are developed successfully for
fiber optic communication and sensing fields. Fiber Bragg
grating (FBG) sensors hold not only the original advances:
light, small, embeddable, and immunity to theelectric-magnetic
interference in optical fiber sensors, but also have
moreadvantages in multiplexing. Since Kersey proposed a simple
method using tunable Fabry-Perot filter to demultiplex multi-
point measurements, it hasbeen a standard method for
multiplexing Bragg grating sensors. However,due to the intensity
variations in the optical fiber system and the nonideal optical
devices, this system still needs to modify for optimization
designs. In this thesis we will discuss that the methods of
compensating the intensity variations of light source, FBG
sensor, and Fabry-Perot tunable filter. All of these
compensating configurations could be constructed by using simple
and cheap electric circuits and devices. Shot noise effect of
these systems will be also analyzed and compared. Furthermore,
the nonlinear response problem of Fabry-Perot tunable filter
will be discussed and solved by utilizing a stable and simple
configuration of Fabry-Perot Etalon.
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