Jeong, Ji Ho Lee, Kwanil Song, Kwang Yong Jeong, Je-Myung Lee, Sang Bae 2024-01-20T16:30:27Z 2024-01-20T16:30:27Z 2021-09-04 2011-09-12 1094-4087 https://pubs.kist.re.kr/handle/201004/129989 We propose and experimentally demonstrate a novel lock-in detection method to avoid a beat noise in Brillouin optical correlation domain analysis (BOCDA) which appears in the sweep of the sensing position and deteriorates the measurement accuracy by distorting the acquired Brillouin gain spectrum. In our analysis, the origin of the beat noise is shown to be the fluctuation of the Brillouin gain induced by the chopping of the intensity-modulated pump wave, and the optimal relation between the modulation and the lock-in frequencies is developed as an effective solution to circumvent the beat noise. (C) 2011 Optical Society of America English OPTICAL SOC AMER DISTRIBUTED FIBER SENSOR STRAIN-MEASUREMENT BOTDA MODULATION PROPOSAL RANGE Variable-frequency lock-in detection for the suppression of beat noise in Brillouin optical correlation domain analysis Article 10.1364/OE.19.018721 1 OPTICS EXPRESS, v.19, no.19, pp.18721 - 18728 OPTICS EXPRESS 19 19 18721 18728 scie scopus 000294781200105 2-s2.0-80052767947 Optics Optics Article DISTRIBUTED FIBER SENSOR STRAIN-MEASUREMENT BOTDA MODULATION PROPOSAL RANGE strain Brillouin