Fig. 1. Experimental setup of BOCDR using a PRBS-modulated LD.

Fig. 2. Electrical PRBS: (a) time series; (b) power spectrum.

Fig. 3. Structure of the FUT in our experimental work.

Fig. 4. (a) Measured Brillouin spectra at different temperatures; (b) temperature-dependence of the BFS.

Fig. 5. Distribution of the Brillouin spectrum along the FUT with a 1-m-long heated section.

Fig. 6. Fitted BFS as a function of position along the FUT with a 1-m-long section heated to 50°C. Inset, 54 cm resolution can be achieved by this method.