| Overview
The Precipitation Radar (PR) onboard TRMM is the first spaceborne rain radar in the world, and was developed by JAXA(Old:NASDA) in cooperation with NICT(Old:CRL).
Major objectives of PR are;(1) to provide 3-dimensional rainfall structure, (2) to achieve quantitative rainfall measurement over land as well as the oceans, and (3) to improve the accuracy of TRMM Microwave Imager (TMI) measurement by providing the rain structure information.
Characteristic
System Parameters
| Radar Type |
Active Phased-array Radar |
| Frequency |
13.796 GHz and 13.802 GHz
(Two-channel frequency agility) |
| Swath Width |
About 215km |
| Observable Range |
Over 20km |
| Range Resolution |
250km |
| Horizontal Resolution |
4.3 km (nadir) |
| Sensitivity |
S/N per pulse >= 0 dB for 0.5 mm/h rain at rain top |
| Independent Samples |
64 |
| Data Rate |
93.5kbps |
| Weight |
465kg |
| Power |
213W |
Antenna
| Antenna Type |
128-element slotted wave guide array antenna |
| Beam Width |
10.71deg. * 0.71deg. |
| Aperture |
2.1m * 2.1m |
| Scan Angle |
+-17deg. |
| Gain |
About 47.4dB |
Transmitter/Receiver Subsystem
| Transmitter Type |
Solid-State Power Amplifiers (SSPAs)(* 128) |
| Peak Power |
Over 700W |
| Pule Width |
1.6ms * 2ch. |
| Pulse Repetition Frequency |
2776Hz |
| Dynamic Range |
About 81.5dB |
Sample Images
 |
Typhoon no.28(1997.12.25) |
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