MULTIPLEXED FIBER OPTIC SENSING SYSTEM AND METHOD

摘要

A sensing system includes plurality of sensors along the lengths of input and output optical fibers. Each sensor receives broadband pulses from the input fiber, dynamically senses a plurality of physical parameters in a one-to-one correspondence with a plurality of predefined wavelength bands, and forms signal pulses from the broadband pulses by transmitting only a single wavelength within each wavelength band. Each single wavelength has a dynamically-varying peak wavelength value indicative of the corresponding sensed physical parameter. The signal pulses from the output optical fiber are directed into one or more interferometers, which produce a phase deviation corresponding to each dynamically-varying peak wavelength value.

主权项

1. A distributed system for measuring physical parameters, comprising:
a source of broadband light; at least one input optical fiber coupled to the source of broadband light; a plurality of sensors coupled to the input optical fiber at spaced locations along the fiber, at least some of the sensors including a plurality of detectors for measuring a physical parameter at the respective location of the sensor, each detector producing an output optical signal by varying a characteristic of the light in response to the physical parameter; a multiplexer configured to selectively couple the light from the at least one input optical fiber to different sensors of the plurality of sensors; at least one output optical fiber coupled to the plurality of sensors and configured to receive and communicate the sensor output optical signals; and an interrogation module coupled to the at least one output optical fiber, the interrogation module comprising,
a demultiplexer coupled to the at least one output optical fiber and configured to separate the output optical signals from different ones of the sensors and from different ones of the detectors; anda converter for converting the output optical signals to electrical output signals.