为了降低布里渊频谱展宽造成的拟合误差,提出采用双边带连续光作为探测信号,并利用干涉谱进行传感。与传统的布里渊增益谱相比,所得频谱在共振频谱附近具有更窄的线宽,预泵浦温度传感中双峰拟合的误差减小,系统的频率分辨率得到了提高,从而实现高空间分辨率和高频率分辨率的基于双边带干涉的预泵浦布里渊光时域分析（BOTDA）系统。实验结果表明,利用所提方法在100 m保偏光纤上可以实现50 cm的空间分辨率和0.37 MHz的频率分辨率。与传统的单边带预泵浦系统相比,相同空间分辨率下所提系统的频率分辨率提高2倍。

In order to reduce the fitting error caused by the broadening of the spectrum, this paper proposes to use the double-sideband continuous light as the detection signal and use its interference spectrum for sensing. Compared with the traditional Brillouin gain spectrum, the obtained spectrum has a narrower linewidth near the resonance spectrum, the error of the double-peak fitting in the pre-pump temperature sensor is reduced, and the frequency resolution of the system is improved, so as to achieve high spatial resolution and high frequency resolution of a pre-pump Brillouin optical time domain analysis （BOTDA） system based on double-sideband interference. Experimental results show that 50 cm spatial resolution and 0.37 MHz frequency resolution can be achieved on 100 m polarization maintaining fiber by using this method. Compared with the traditional single side band pre-pump system, the frequency resolution of the system is increased by 2 times under the same spatial resolution.