Transmission Characteristics of Double Fiber Ring with Fiber Bragg GratingJOSA B
- Biswajit Ghosh and SANJOY MANDAL
- received 11/14/2019; accepted 01/15/2020; posted 01/16/2020; Doc. ID 383167
- Abstract: The Z domain model of double fiber ring (DR) with a uniform fiber Bragg grating (FBG) incorporated using two optical couplers and a DRFBG configuration using three optical couplers is developed. The developed mathematical model is used to determine the transmission response. The performance of double ring with FBG using two optical couplers is compared with previously measured results and is found to be in very close agreement. A similar DRFBG structure with three optical couplers is proposed. By proper optimization of FBG reflectivity and power coupling ratios, a narrow FWHM (Full width at half maximum) with virtually zero crosstalk is achieved. Compared with the double ring configuration using two optical couplers, the proposed structure yields a higher finesse giving much better spectral selectivity. The performance of the proposed structure as strain sensor is investigated using the delay line signal processing technique in Z domain. The detection resolution of strain variation is much enhanced.