Fiber optic interferometric hydrophone using fiber Bragg grating with wavelength division multiplexing

A study was conducted to evaluate the application of the wavelength division multiplexing (WDM) scheme to construct an array system of fiber optic interferometric hydrophones by using fiber Bragg grating (FBG). FBG reflectors simplifies the construction of the distributed chain of the hydrophones by eliminating the large number of couplers, joints, and other interconnects in fibre optic hydrophones. The study found that the WDM allows many TDM signals at different wavelengths to combined on a single fiber. The study stated that WDM helps to construct a multiplexing scheme with high sampling frequency in contrast with TDM. The study found that the sensitivities of hydrophones with WDM and a single scheme are similar and the frequency noise property of the fiber optic hydrophones remains same using WDM schemes.