10 km 以上遠方での傾斜利用 BOCDR の動作に関する李（M2）の論文が Electronics Letters に掲載されました。
H. Lee, K. Noda, Y. Mizuno, and K. Nakamura, “Distributed temperature sensing based on slope-assisted Brillouin optical correlation-domain reflectometry with over 10 km measurement range,” Electron. Lett., vol. 55, no. 5, pp. 276-278 (2019).
We demonstrate distributed temperature sensing based on slope-assisted Brillouin optical correlation-domain reflectometry (BOCDR) with a long measurement range of >10 km. We find that, to achieve such a long-range measurement, a delay line in a reference path needs to be at least 4 times longer than the sensing fibre. In addition, we show that the use of such a long delay line induces forward-propagating Brillouin-scattered light in the reference path, which deteriorates the signal-to-noise ratio (SNR) of the system and should be suppressed. Finally, by exploiting a beyond-nominal-resolution effect of the slope-assisted BOCDR, we detect a 3-m-long heated section in a 13-km-long silica fibre in a distributed manner; the reason for its low SNR is also discussed.