Communications Research Laboratory (CRL) is developing a new C-band radar, which is named COBRA (CRL Okinawa Bistatic polarimetric Radar). The COBRA was installed on a mountain peak in Nago city, Okinawa, and the test observation was started in April 2002. The COBRA has new observation functions, which include six kinds of polarizations (H, V, +45, -45, RC, and LC) transmitted pulse by pulse, variable PRFs (250-3000 Hz) and antenna rotation speeds (0.5-10 rpm), a bistatic Doppler network using the two-faces bistatic antenna technology, and so on. The aim of the COBRA development is to apply the next-generation technology to meteorological and hydrological observations.