SYSTEM AND METHOD FOR SENSING MANY FIBER SENSORS USING TIME-DIVISION MULTIPLEXING AND WAVELENGTH DIVISION MULTIPLEXING

摘要

A system and method for discriminately measuring the response of a plurality of spatially separated fiber sensors positioned along an optical fiber using a sweep of electromagnetic radiation. Each fiber sensor affects the transmission of a particular wavelength of electromagnetic radiation and the particular wavelength affected by a given fiber sensor is dependent on at least one environmental property of the given fiber sensor. By detecting the particular wavelength affected by a given sensor, it is possible to determine the environmental property of the given sensor.

主权项

1. A system for discriminately measuring the response of a plurality of spatially separated fiber sensors positioned along an optical fiber, the system comprising:
an electromagnetic radiation source configured to emit electromagnetic radiation having a wavelength within an emission wavelength range, wherein the emitted electromagnetic radiation is transmitted by the optical fiber; the optical fiber including the plurality of fiber sensors, wherein:
each fiber sensor affects a transmission of a particular wavelength of the electromagnetic radiation transmitted by the optical fiber; andfor a given fiber sensor of the plurality of fiber sensors:
the particular wavelength affected by the given fiber sensor is dependent on at least one environmental property of the given fiber sensor; andthe particular wavelength affected by the given fiber sensor is constrained within a defined subrange of the emission wavelength range; a controller configured to control the electromagnetic radiation output by the electromagnetic radiation source, such that:
at a given time, the electromagnetic radiation source outputs a specified wavelength of electromagnetic radiation; andthe specified wavelength is varied in time to produce an output sweep within the emission wavelength range, wherein:
the output sweep includes at least two repetitions of a combination of a subsweep followed by a pause;each of the repetitions begins at an initial wavelength and ends at an ending wavelength;each subsweep comprises a sweep across a subrange of wavelengths beginning with the initial wavelength and ending at the ending wavelength;during each pause following the subsweep, the wavelength of the electromagnetic radiation output by the electromagnetic radiation source is maintained for a period of time at a pause wavelength; andthe initial wavelength differs for each repetition of the subsweep and the ending wavelength differs for each repetition of the subsweep; and a detector configured to detect wavelengths of the electromagnetic radiation effected by the fiber sensors, wherein the detector is configured to record the detected effected wavelengths and a time at which each effected wavelength was detected.