在传统的布里渊光时域反射(BOTDR)技术中，空间分辨率和自发布里渊散射谱宽相互制约。针对这一问题，将探测光改进为超短双脉冲，并利用检测频谱包络的方法得到BOTDR系统的空间分辨率。该方法提高了BOTDR系统的空间分辨率，同时可避免压窄脉冲引起的布里渊增益谱展宽对测量精度的影响。实验表明，该方案能实现0.5 m空间分辨率的温度测量，避免自发布里渊散射谱发生较大展宽。

In conventional Brillouin optical time domain reflectometry (BOTDR), mutual restraint between the spatial resolution and the width of spontaneous Brillouin scattering spectrum can not be avoided. To solve this problem, we ameliorated the approach using double ultra-short pulses as probe light. By detecting spectral envelope, the spatial resolution of BOTDR can be extracted. This method improves the spatial resolution of the BOTDR system and meanwhile avoids the influence of Brillouin gain spectrum broadening caused by narrowing pulse on measurement accuracy. The experimental results show that with this novel BOTDR system, the temperature measurement can be realized at a 0.5 m spatial resolution, and the large broadening of the spontaneous Brillouin scattering spectrum can be avoided.