Vaisala RVP900 - Page 243

Threshold
Option
Description
3×3
Switches on the 3x3 2D output filter. See 7.5.3 Speckle Filter Processing (page 210).
RVP900 automatically handles all of the pipelining overhead associated with running the
3×3 filter. Valid output data are always obtained in response to every PROC command.
CCB
Circular autocorrelation bias correction. Setting this bit causes non-windowed spectra to
produce autocorrelation terms that exactly match those that would be computed by
traditional PPP sums, that is, with the spurious end-around term removed.
Lsr
Lsr 1D reflectivity speckle remover. When set, range speckles in dBT, dBTa, dBZ, dBZa,
SNR, ZDR, LDRH, and LDRV are removed.
Dsr
Dsr 1D Doppler speckle remover. When set, range speckles in V, W, PhiDP, PhiH, PhiV,
RhoHV, RhoH, RhoV, and KDP are removed.
Rnv
Range normalization of reflectivity data. This bit also enables intervening gas attenuation
correction.
HClass is 1D speckle-filtered when Lsr or Dsr is set.
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
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| Log Slope65536 * dB / (LSB) | Input 3
|---------------------------------------------------------------|
This number defines the multiplicative constant that converts the signal power in dB to the
units of the 12-bit Log of power in sample time series outputs. One fourth (1/4) of
this slope is used to generate the Log of Measured Noise Level output from GPARM
(word 6). The recommended value is 0.03 (1966). This gives a dynamic range of 122 dB in 12
bits.
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
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| LOG Threshold in 1/16 of dB | Input 4
|---------------------------------------------------------------|
Reflectivity values below this level can result in thresholding of data, if the threshold control
flags (see below) include LOG Noise bits. The threshold value is always non-negative. For
the comparison test, see 7.5 Thresholding (page 207).
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
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| | | | | | | | | | | | | | | | |
| Clutter Correction (CCOR) Threshold in 1/16 of dB | Input 5
|---------------------------------------------------------------|
Chapter 8 – Host Computer Commands
241