Ruiz Lombera, RubénUrricelqui Polvorinos, JavierSagüés García, MikelMirapeix, JesúsLópez Higuera, José MiguelLoayssa Lara, Alayn2016-11-152016-11-152015R. Ruiz-Lombera, J. Urricelqui, M. Sagues, J. Mirapeix, J. M. López-Higuera and A. Loayssa, "Overcoming Nonlocal Effects and Brillouin Threshold Limitations in Brillouin Optical Time-Domain Sensors," in IEEE Photonics Journal, vol. 7, no. 6, pp. 1-9, Dec. 2015. doi: 10.1109/JPHOT.2015.24985431943-0655 (Print)1943-0655 (Electronic)10.1109/JPHOT.2015.2498543https://academica-e.unavarra.es/handle/2454/22707We demonstrate, for the first time to our knowledge, a Brillouin optical time domain analysis (BOTDA) sensor that is able to operate with a probe power larger than the Brillouin threshold of the deployed sensing fiber and that is free from detrimental non-local effects. The technique is based on a dual-probe-sideband setup in which an optical frequency modulation of the probe waves along the fiber is introduced. This makes the optical frequency of the Brillouin interactions induced by each probe wave on the pump to vary along the fiber so that two broadband Brillouin gain and loss spectra that perfectly compensate are created. As a consequence, the pulse spectral components remain undistorted avoiding non-local effects. Therefore, a very large probe power can be injected, which improves the signal-to-noise ratio in detection for long-range BOTDA. Moreover, the probe power can even exceed the Brillouin threshold limit due to their frequency modulation, which reduces the effective amplification of spontaneous Brillouin scattering in the fiber. Experiments demonstrate the technique in a 50-km sensing link in which 8 dBm of probe power is injected.application/pdfeng© 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Brillouin distributed sensorsBrillouin optical time domain analysisNon-local effectsBrillouin thresholdOptical fiber sensorsStimulated Brillouin scatteringinfo:eu-repo/semantics/articleinfo:eu-repo/semantics/openAccess