An intensity modulated broadband optical signal source is arranged to
produce optical signals in a plurality of wavelength bands. A
demultiplexer/multiplexer pair receives optical signals from the optical
signal source and produces a separate optical signal for each wavelength
band. An optical coupler is arranged to receive the separate optical
signals. Optical fiber loops connected to the optical coupler guides both
clockwise and counter clockwise waves for each of the separate optical
signals. The optical signals propagate through a sensor in each loop and
then combine in the optical coupler to form a plurality of interference
signals in each wavelength band. A multiplexer is optically coupled to
the optical coupler to receive the interference signals therefrom, and a
detector array having a selected detector corresponding to the each of
the plurality of wavelength bands is arranged to provide an electrical
signal that indicates the interference signals for each wavelength band.