Ocean Surface Backscattering at Extremely Low Grazing Angles Observed by C-band Polarimetric Doppler Weather Radar
نویسندگان
چکیده
RADAR A C-band (5.34 Ghz) multi-parameter radar has been operated in the Okinawa Subtropical Remote Sensing Center, National Institute of Information and Communications Technology (NICT), Japan. It is a full-polarimetric radar with Doppler measurement capability, located on the top of a mountain in the center of the Okinawa Island (128.06oE, 26.59oN, 360m above sea level), southernmost part of Japan. It observes precipitation in sub-tropical maritime climate region, aiming at precise estimates of rainfall rates and classifying precipitation particles [1]. The radar has two Klystron transmitters of 250 kW to transmit alternate polarization (horizontal or vertical) signals by pulse to pulse, and two receivers to receive both horizontal and vertical polarizations of backscattering echo from the targets. The radar has typically 200 km coverage with 0.9 degree beamwidth, transmitting 2.0/1.0/0.5 sec pulses, with its parabolic antenna of 4.5 m diameter. The spatial resolution, therefore, is a few kilometers in azimuth and a few hundreds meters in range.
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