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TRMM_readme_PR_RayHeader.shtml

PR Power Ray Header
Name Format Description
Ray Start 2-byte integer Starting range bin number of Normal sample
Ray Size 2-byte integer Number of Normal samples in the ray
Angle 4-byte float Angle (degrees) of the ray from nadir. The sign of the angle is consistent with the sensor y-axis, i.e., the angle is positive to the right of the direction of travel if the spacecraft is in normal mode.
Starting Bin Distance 4-byte float Distance (m) between the satellite and the starting bin number of the Normal sample for the ray
Rain Threshold 1 4-byte float Threshold used in minimum echo test (unitless). Value set by NASDA
Rain Threshold 2 4-byte float Threshold used in minimum echo test (unitless). Value set by NASDA
Transmitter Antenna Gain 4-byte float Transmitted radar antenna effectiveness (dB)
Receiver Antenna Gain 4-byte float Received radar antenna effectiveness (dB)
One-way 3dB Along-track Beamwidth 4-byte float Radar beamwidth (radians) at the point transmitted power reaches one half of peak power in the along-track direction.
One-way 3dB Cross-track Beamwidth 4-byte float Radar beamwidth (radians) at the point transmitted power reaches one half of peak power along the cross-track.
Equivalent wavelength 4-byte float Equivalent wavelength (m).
Radar Constant 4-byte float Radar constant dC (units are dB), which relates Received Power to Radar Reflectivity. dC depends on angle.
PR Internal delayed time 4-byte float The time (seconds) between when echo returns at antenna and when echo is recorded in onboard processor.
Range Bin Size 4-byte float The vertical resolution of Normal sample bin (250 m).
Logarithmic Averaging Offset 4-byte float The offset value (dB) between logarithmic average and normal average (+2.507dB).
Mainlobe Clutter Edge 1-byte integer Absolute value of the difference in Range Bin Numbers between the detected surface and the edge of the clutter from the mainlobe.
Sidelobe Clutter Range [3] 3 X 1-byte integer Absolute value of the difference in Range Bin Numbers between the detected surface and the clutter position from the sidelobe. A zero means no clutter indicated in this field since less than 3 bins contained significant clutter.
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Last updated: Sep 09, 2009 02:26 PM ET
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