A microwave coherent detection system is presented which can be used to simultaneously measure the temperature and
strain distribution along a fiber with high accuracy based on spontaneous Brillouin scattering. The system measures the
Brillouin scattering and Rayleigh scattering in fiber simultaneously, using the ratio of the Rayleigh and spontaneous
Brillouin backscattered light called Landau-Placzek Ratio (LPR), and scans the Brillouin spectrum to obtain the desired
information. The measurement system setup is showed in this paper, and the system performances such as the spatial
resolution, the spectrum, the measurement accuracy, the dynamic range, and the measurement time are analyzed. The
analysis shows that the system can achieve the spatial resolution of 2m, temperature resolution of 1  and strain
resolution of 20με.