TIME-AND-SPATIAL-MULTIPLEXING TREE TOPOLOGY FOR FIBEROPTIC BRAGG-GRATING SENSORS WITH INTERFEROMETRIC WAVELENGTH-SHIFT DETECTION

A combined time-and-spatial-division-multiplexed tree topology with ei ght fiber-optic Bragg-grating sensors operating at the 830-nm waveleng th was constructed and tested for both quasistatic and periodic strain and temperature measurements. The system uses a interferometric wavel ength-shift discriminator and incorporates a reference channel for the rmal drift compensation in the output. Dynamic sensor sensitivity, as determined by primary noise sources, is evaluated, and numerical resul ts are presented and compared with experimental results. (C) 1996 Opti cal Society of America