Single end structure dynamic measurement's brillouin optical fiber sensing system

The utility model discloses a single end structure dynamic measurement's brillouin optical fiber sensing system, sensing system laser light source enters the input of modulation high extinction ratio module through two way continuous lights of first coupler output, first via continuous light, and modulation high extinction ratio module is connected to the one input of second coupler, second way continuous light enters the phase shift modulation module, and the phase shift modulation module is connected to another input of second coupler, the second coupler inserts 1 port of optical circulator, and 2 ports of optical circulator connect with with single -ended module through sensing fiber, 3 ports and the demodulation module of optical circulator connect with. The nominal measuring distance was effective measuring distance promptly during BOTDA had been realized to the single end structure, and solve prior art system in actual measurement needs the bi -polar to insert and effective sensing distance has only the half the problem of nominal sensing length, improved electric optic modem the extinction ratio, reduced measuring time, realized the monitor function of dynamic measurement, long distance dynamic strain.