@ARTICLE{Dwivedi_Krishna_Mohan_Design_2020,
 author={Dwivedi, Krishna Mohan and Trivedi, Gaurav and Khijwania, Sunil K. and Osuch, Tomasz},
 volume={vol. 27},
 number={No 2},
 journal={Metrology and Measurement Systems},
 pages={289-300},
 howpublished={online},
 year={2020},
 publisher={Polish Academy of Sciences Committee on Metrology and Scientific Instrumentation},
 abstract={A π-phase-shifted fiber Bragg grating (π-FBG) shows high sensitivity to the ultrasonic (US) wave as compared to the conventional FBG due to the strong slow-light phenomenon at the resonance peak. However, its sensitivity is limited by the interrogation schemes. A combination of π-FBG and unbalanced fiber Mach– Zehnder interferometer (F-MZI) are theoretically analyzed and optimized for the highly sensitive acoustic sensor. The coupled-mode theory (CMT) and transfer matrix method (TMM) are used to establish the numerical modelling of π-FBG. For the optimized grating parameters of π-FBG, the proposed sensing system shows the high strain sensitivity of 1.2 × 108/ε, the highest dynamic strain resolution of 4.1fε/√Hz, and the highest wavelength shift resolution of 4.9 × 10−9 pm. Further, the proposed sensing system strongly supports both time andwavelength division multiplexing techniques. Therefore, the proposed sensing system shows extreme importance in single as well as quasi-distributed US acoustic wave sensing networks.},
 type={Article},
 title={Design and numerical analysis of a highly sensitive ultrasonic acoustic sensor based on -phase-shifted fiber Bragg grating and fiber Mach–Zehnder interferometer interrogation},
 URL={http://journals.pan.pl/Content/116013/PDF/art06.pdf},
 doi={10.24425/mms.2020.132775},
 keywords={π-FBG, unbalanced F-MZI, strain sensitivity, ultrasonic acoustic sensor},
}