Abstract
Increasing the capacity of an array of sensors is a major challenge in fiber-optic sensing networks. Whereas fiber Bragg grating (FBG) sensors can be discriminated in the spectrum domain, through the popular wavelength-division-multiplexing (WDM) approach, Fabry–Perot interferometry (FPI) sensors have a broad spectrum and are not suitable for WDM. In this paper, a novel approach for the simultaneous detection of multiple FPI sensors is proposed. The key is decoding sensors in the optical cepstrum (spectrum of the optical spectrum) domain, using a Capon estimator. Subsequently, the small cepstrum shifts are accurately detected with a fast-phase correlation method. This approach is labeled cepstrum-division multiplexing (CDM). CDM has been tested on a simulated FPI array, with a coarse wavelength grid typical of most FBG interrogators. Unambiguous and simultaneous detection of 20–39 sensors is achieved, improving over previous methods limited to 1–3 sensors; 0.04-nm accuracy on cavity length estimation has been achieved. A preliminary experimental demonstration has been set up to validate the CDM approach.
© 2016 IEEE
PDF Article
More Like This
Cited By
You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
Contact your librarian or system administrator
or
Login to access Optica Member Subscription