METHOD AND APPARATUS FOR MOTION COMPENSATION IN INTERFEROMETRIC SENSING SYSTEMS

摘要

An optical interrogation system, e.g., an OFDR-based system, measures local changes, of index of refraction of a sensing light guide subjected to a time-varying disturbance. Interferometric measurement signals detected for a length of the sensing light guide are transformed into the spectral domain. A time varying signal is determined from the transformed interferometric measurement data set. A compensating signal is determined from the time varying signal which is used to compensate the interferometric measurement data set for the time-varying disturbance. Further robustness is achieved using averaging and strain compensation. The compensation technique may be applied along the length of the light guide.

主权项

1. An optical interrogation system for measuring a parameter of a sensing light guide subjected to a time-varying disturbance, comprising:
an optical interferometric interrogator; optical detection circuitry, coupled to the optical interferometric interrogator, for detecting optical interferometric measurement signals for a length of the sensing light guide; and data processing circuitry configured to:
receive interferometric measurement signals from the optical detection circuitry,generate an interferometric measurement data set for the length of the sensing light guide;transform the interferometric measurement data set into the spectral domain;determine a time varying signal from the transformed interferometric measurement data set;determine a compensating signal from the time varying signal; anduse the compensating signal to compensate the interferometric measurement data set for the time-varying disturbance to enhance the measurement of the parameter.