Development of a multiparameter radar system on mobile platform

National Research Institute for Earth Science and Disaster Prevention (NIED) has developed a multiparameter radar system on mobile platform under contract with Mitsubishi Electric Corporation in order to observe cloud and precipitation systems through their whole life cycles. The developed radar system consists of an X-band radar subsystem for rain/snow observation and a dual-millimeter-wavelength (Ka- and W-band) radar subsystem mainly used for non-precipitation clouds observation. Each subsystem is mounted on a truck of 4-tons for field experiments.

Doppler measurements are available at all frequencies, and the X-band and W-band radars have a function of dual-polarization. The polarimetric function is expected to be used for discrimination of particle type and to improve accuracy of rain rate measurements. The cloud radar subsystem uses a single Cassegrain antenna with 2.1 m diameter to make collocated measurements at both Ka- and W-bands. This enables a measurement of liquid water contents in clouds by dual-wavelength method. Since the X-band radar subsystem has equipment for satellite communication, observed radar data can be instantly transmitted to the laboratory and open to public via World Wide Web.

In order to study on the estimation methods of cloud and precipitation parameters and cloud formation and precipitation processes, we are planning several radar observations in combination with the other observations by a microwave radiometer, an instrumented aircraft, video sondes and fine GPS-network in cooperation with the other organizations.