本論文主要介紹一新式的以FBG構成Fabry-Perot干涉儀之入侵感測系統。此系統總共有四個防區，每個防區皆有一對FBG，四個防區由一條SMF和四對FBG串接在一起，每一對FBG有相同的波長，並且有四個不同波長的雷射提供給四個防區。光從雷射共振腔輸出，經過Fabry-Perot 干涉儀，再反射回相對應波長的PD，然後進入DAQ由電腦來進行觀察。 我們在戶外做實驗，將四個防區的系統設置在山上，並將50公尺防區中的約1公尺長的光纜綁在鐵絲網上，然後由DAQ觀察四個即時訊號波形，透過即時波形，電腦會算出各防區的三個參數visibility, level crossing和frequency ratio，然後再分別找出各個防區的閾值，假設三個閾值都大於設定值，系統可立即得知哪一防區遭受入侵，若有多個防區同時遭受入侵也能同時偵測，不會有防區間干擾情形。本論文之感測系統是只需使用一條單模光纖即可串連四個防區，再通過設計降低成本並改善防區間嚴重干擾的問題。

This thisis introduces fiber-optic perimeter intrusion detection system base on the Fabry-Perot interferometer for the perimeter zones . Specifically, each perimeter zone contains a Fabry-Perot interferometer with a pairs of fiber Bragg gratings used as end mirrors. Four perimeter zones are connected in series using a single SMF(single-mode fiber) with four pairs of fiber Bragg gratings distributed on the single SMF. The pair of fiber Bragg gratings for each perimeter zone have the same Bragg wavelength, while different pairs have different Bragg wavelengths, thus allowing four laser lights at different wavelengths to be used for intrusion detections at different perimeter zones. The lights emitting from respective laser resonators are directed to their respective Fabry-Perot interferometers, and are sent back to respective photodetectors for intrusion detection. . By using a data acquisitim module, the four signal waveforms are loaded into a computer, which then gives three parameters, i.e., visibility, level crossing and frequency ratio for each detected signal for the four perimeter zones. The intrusion detection algorithm is then used to tell which perimeter zone is intruded by examining the three aforementioned parameters. We have tested the proposed four-perimeter-zone intrusion detection system at an outdoor environment, with extremely high alarm rate upon intrusion and zero misalarm rate for the case of non-intrusion.

[1] Z. G. Qin, T. Zhu, L. Chen, and X. Y. Bao,“High sensitivity distributed vibration sensor based on polarization-maintaining configurations of phase-OTDR,” IEEE Photonics Technology Letters, vol. 23, no. 15, pp. 1091-1093, Aug. 2011.
[2] F. Verluise, V. Laude, Z. Cheng, Ch. Spielmann, and P. Tournois, “Amplitude and Phase Control of Ultrashort Pulses by Use of an Acousto-Optic Programmable Dispersive Filter: Pulse Compression and Shaping”,Optics Letters, Optical Society of America, Vol.25, No.8, pp.575-577, 2000.
[3] K. O. Hill, Y. Fujii, D. C. Johnson, and B. S. Kawasaki, “Photosensitivity in optical fiber waveguides: Application to reflection filter fabrication,” Applied Physics Letters, Vol. 32, No. 10, pp.647-649, American Institute of Physics, 1978
[4] M. K. Barnoski and S. M. Jensen, “Fiber Waveguides: a Novel Technique for Investigating Attenuation Characteristics,” Applied Optics, Vol.15, No.9, pp.2112-2115, Optical Society of America, 1976.
[5] Y. Shan, W Ji, and X Dong,“An enhanced distributed acoustic sensor based on UWFBG and self-heterodyne detection,” Journal of Lightwave Technology, vol. 37, no. 11, pp. 2700-2705, Jun. 2019.
[6] S. Qiuheng and P. Hekuo,“A novel weak-scattering michelson interferometer based on PBS for long-distance disturbance localization,” Journal of Lightwave Technology, vol. 38, no. 6, pp. 1543-1549, Nov. 2019.
[7] Y. -H. Lin, B. -H. Zheng and L. Wang, "Cascaded Fiber-Optic Interferometers for Multi-Perimeter-Zone Intrusion Detection With a Single Fiber Used for Each Defended Zone," IEEE Sensors Journal, vol. 21, no. 9, pp. 10685-10694, 1 May1, 2021, doi: 10.1109/JSEN.2021.3059645.
[8] 鄭博鴻，「使用單條光纖架構成環形共振腔干涉儀之分區型人為入侵感測系統之研究」，國立清華大學光電工程研究所碩士班碩士論文，民國一百一十年七月。
[9] 楊議鈞，「使用FBG構成Fabry-Perot干涉儀之防區型感測系統之研究」，國立清華大學光電工程研究所碩士班碩士論文，民國一百一十一年七月。
[10] D.B. Mortimore, "Fiber loop reflectors", Journal of Lightwave Technology, Vol. 6, No. 7, pp. 1217-1224, IEEE, 1988.
[11] J. C. Campbell, A. G. Dentai, W. S. Holden, and B. L. Kasper, “High-Performance Avalanche Photodiode with Separate Absorption, ‘Grading’, and Multiplication Regions”, Electronics Letters, Vol. 19, pp. 818-820, 1983.
[12] Saravanos, C., & Lowe, “Characterization Techniques of Single-Mode Fibers”, Antenna Technology and Applied Electromagnetics, 1877. ANTEM 1988. Symposium on pp. 1-6, IEEE, 1988.
[13] Gloge, D., “Optical Fiber Theory: Opportunities for Advancement Abound,” Radio Science, Vol. 12, No. 4, pp. 479-490, 1977.
[14] Okoshi, T., “Recent Advances in Coherent Optical Fiber Communication Systems”, Journal of Lightwave Technology, Vol. 5, No. 1, pp. 44-52, IEEE, 1987.
[15] Shecheng Gao, Weigang Zhang, Zhi-Yong Bai, Hao Zhang, Wei Lin, Li Wang, and Jieliang Li. “Microfiber-Enabled In-line Fabry–Pérot Interferometer for High-Sensitive Force and Refractive Index Sensing”, Journal of Lightwave Technology, Vol. 32, No. 9, pp. 1682-1688, IEEE, 2014.
[16] Li Wei, Anum Khattak, Connor Martz, Da-Peng Zhou, “Tunable Multimode Fiber Based Filter and Its Application in Cost-Effective Interrogation of Fiber-Optic Temperature Sensors,” IEEE Photonics Journal, Vol. 9, No.2, 2017.
[17] Charusluk Viphavakit, Sinead O’ Keeffe, Minghong Yang, Stefan Andersson-Engels, and Elfed Lewis, “Gold Enhanced Hemoglobin Interaction in a
Fabry–Pérot Based Optical Fiber Sensor for Measurement of Blood Refractive Index”, Journal of Lightwave Technology, Vol.36, No.4, pp.1118-1124, IEEE, 2018.
[18] Lihua Dai, Ming Wang, Dongyan Cai, Hua Rong, Jiali Zhu, Sheng Jia, and Jingjing You, “Optical Fiber Fabry–Pérot Pressure Sensor Based on a Polymer Structure”, IEEE Photonics Technology Letters, Vol. 25, No. 24, pp.2505-2508, 2013.
[19] Yong Chen, Li-Xin Zhou, and Huan-Lin Liu, “A Fiber Bragg Grating Sensor Perimeter Intrusion Localization Method Optimized by Improved
Particle Swarm Optimization Algorithm,” IEEE Sensors Journal, Vol. 18, No. 3, pp.1243-1249, 2018.
[20] D. K. W. Lam, and B. K. Garside, “Characterization of single-mode optical fiber filters,” Applied Optics, No. 20, pp. 440-445, Optical Society of America, 1989.
[21] Bai-Ou Guan, Hwa-Yaw Tam, and Shun-Yee Liu, “Temperature-Independent Fiber Bragg Grating Tilt Sensor,” IEEE Photonics Technology Letters, Vol.16, No.1, pp.224-226, 2004.
[22] Y. S. Hsu, Likarn Wang, Wen-Fung Liu, and Y. J. Chiang, “Temperature Compensation of Optical Fiber Bragg Grating Pressure Sensor,” IEEE Photonics Technology Letters, Vol.18, No.7, pp.874-876, 2006.
[23]Juan C. Juarez, Eric W. Maier, Kyoo Nam Choi, and Henry F. Taylor, “Distributed Fiber-Optic Intrusion Sensor System,” Journal of Lightwave Technology, Vol.23, No.6, pp.2081-2087, IEEE, 2005.
[24] K. -S. Lin, K. -H. Yeh, Y. -J. Chiang and L. Wang, "Fiber-Optic Perimeter Intrusion Detection by Employing a Fiber Laser Cavity in Each Defensed Zone," IEEE Sensors Journal, vol. 18, no. 20, pp. 8352-8360, 15 Oct.15, 2018, doi: 10.1109/JSEN.2018.2866223.
[25] Shihong Huang, Tao Zhu, Zhenzhou Cao, Min Liu, Ming Deng, Jianguo Liu, and Xiong Li, “Laser Linewidth Measurement Based on Amplitude Difference Comparison of Coherent Envelope”, IEEE Photonics Technology Letters, Vol.28, No.7, pp.759-762, 2016.
[26] H. Hsieh, K. -S. Hsu, T. -L. Jong and L. Wang, "Multi-Zone Fiber-Optic Intrusion Detection System With Active Unbalanced Michelson Interferometer Used for Security of Each Defended Zone," IEEE Sensors Journal, vol. 20, no. 3, pp. 1607-1618, 1 Feb.1, 2020, doi: 10.1109/JSEN.2019.2946904.