A long-range and high-resolution reflectometry by synthesis of optical coherence function at region beyond the coherence length is proposed. We discuss and simulate the principle of the reflectometry system. In basic experiments, the reflectivity distribution is successfully measured at the region beyond the coherence length with a spatial resolution of 19cm and a measurement range of 1km. We have also proposed two methods to improve dynamic range of the system. In the experiments, dynamic range of 45dB is successfully achieved.