Code division multiplexing in interferometric optical fiber sensor networks

Abstract

Code division multiplexing (CDM) is a useful method to address optical fiber sensors in remote networks by means of a single optical carrier. Our past studies of CDM for fiber optic networks of intensity modulating devices revealed that sensor-sensor crosstalk levels in the range of -60 dB are within reach and that a large number of sensor signals can be multiplexed. Our current effort aims to analyse the noise properties of interferometric networks interrogated using this scheme. Typical targeted figures of merits are; noise < 10 /spl mu/rad//spl radic/Hz, dynamic range > 80 dB, sensor bandwidth > 5 kHz, sensor to sensor crosstalk < 40 dB, number of sensors in each subarray > 30.