We present a signal formula for correlation domain Brillouin analysis that uses short pulse trains arranged at different power intervals. The proposed signal can be realized by using only an intensity modulator, and the signal period (the measurement range) and the signal length can be independently realized without using an additional modulator for time gating. In the numerical analysis, we show that the proposed scheme obtains a gain advantage over the conventional scheme for fibers under test of approximately a few hundred meters when the available pump average power is limited. In the experiment, it was demonstrated that Brillouin frequency shifts can be discriminated with a spatial resolution of 5 cm over a 95-m-long fiber.
展开▼