A sensor device that uses a number of bragg grating (FBG) sensors and
novel interrogation system with a ring cavity configuration for
simultaneous time-division-multiplexex (TDM) and
wavelength-division-multiplexed (WDM) interrogation of FBG sensors. The
ring cavity includes an amplifier, and output coupler and an optical
circulator. The coupler is connected to a wavelength measuring system and
the optical circulator is connected to the FBG sensors. The FBG sensors
can be in a number of groups. TDM interrogation is applied to each group
of FBG sensors while WDM interrogation is applied to each FBG sensors
within each group.