Abstract: This article describes design construction and characterization of a transistorized X-band ground-based scatterometer. A FM-CW system is adopted. Two antennas transmitter and receiver are parellally mounted on the top of a crane boom(8 to 12 meters above the ground). The measurement of backscattering coefficients σ⁰ can be obtained with four states of polarizations (HH, VV, VH and HV) in the range of azimuth angles 0~330° and elevation angles 0~85°. The system consists of RF assembly and a control box, with a multiple-core between them.