Vaisala RVP900, User Manual

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Parameter Description 8-bit Format 16-bit Format
ZDR
Selects differential
reflectivity data.
The level in decibels is computed
from the unsigned byte N as:
��� = �128
16
The overall range is from -7.935 dB
to +7.935 dB in 1\16 dB steps as
follows:
0
Indicates no reflectivity
data available at this range
1
-7.9375 dB
128
0.0000 dB
255
+7.9375 dB
Same as 16-bit decibel format for
Z .
KDP
Selects dual
polarization specific
differential phase
data.
Values are coded into an unsigned
byte using a logarithmic scale.
The KDP angles are multiplied by
the wavelength in cm (to reduce
dynamic range) and then
converted to a log scale
separately for both signs.
The minimum value is 0.25
deg*cm/km.
The maximum value is 150.0
deg*cm/km.
A code of zero represents no data
A code of 128 represents 0
deg*cm/km.
The conversion equation for
positive values (codes from 129 to
255) is:
��� × � = 0.25 × 600 � − 129
126
The conversion equation for
negative values (codes from 1 to
127) is:
��� × � = − 0.25
× 600 127 − �
126
Same as 16-bit decibel format for
Z , except that the units are
hundredths of degrees per
kilometer. No weighting by
wavelength is introduced.
RVP900 User Guide M211322EN-J
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