Load custom range normalization (LDRNV)
Reflectivities computed by RVP10 are usually
corrected for range effects by adding an offset in decibels equal to 20 log(R/1
km), where R is the range in kilometers. This correction is based
on a simple filled beam geometry, and is sufficiently accurate for most meteorological
observations.
The LDRNV command is for applications that require an alternate custom range correction, for example, if an external user-supplied STC waveform drives the radar receiver's LNA.
LDRNV loads a
251-word custom correction table holding values in hundredths of decibels over 5 decades of
log(range) from 0.01km ... 1000km. There are 50 table entries per decade of
range. The range in kilometers corresponding to an input word #N is
10[{{N-1}<devide>50}- 2], and the default correction table
(automatically used on power-up) is 40(N - 101).
The table values are stored and interpolated when RVP10 loads a new range mask. Custom values for the user ranges are then computed. See Load Range Mask (LRMSK).
The LDRNV command must be issued only once, before choosing the working set of range bins.
The linear intervening gas attenuation correction (see Setup operating parameters (SOPRM)) is always added to the reflectivity data, regardless of whether default or custom range normalization is enabled. If this is undesirable, set the intervening gas slope to 0.
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
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| | 1 0 1 0 1 | Command
|--------------------------------------------|-------------------| 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
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| | | | | | | | | | | | | | | | |
| Signed Hundredths dB of Range Normalization for Range 0.01 km | Input 1
|----------------------------------------------------------------| 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
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| | | | | | | | | | | | | | | | |
| Signed Hundredths dB of Range Normalization for Range 1000 km | Input 251
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