Vaisala RVP900 User Manual

USER’S MANUAL__________________________________________________________________
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When Input #1 is zero, then the arguments take on an alternate form that
allows an array of N (up to 64) trigger periods to be specified, and also
gives much finer time resolution in the choice of each period. The XARGS
command is first used to load an array of N 32-bit words that define the
trigger period(s) in nanoseconds. The RVP900 will then generate triggers
whose shapes (relative starts and widths) are identical for each pulse, but
whose periods follow the selected sequence. Trigger patterns such as these
are intended to support research customers who use the real-time (I,Q) data
stream directly.
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7.15 Load Antenna Synchronization Table
(LSYNC)
The RVP900 can operate in a mode wherein radar data are acquired in
synchronization with the antenna motion along either the azimuth or
elevation axis. This special feature frees the user computer from having to
separately monitor the antenna angles and request each data ray
individually. To use this mode, it is assumed that TAG0-15 are wired to
receive azimuth angles, and that TAG15-31 are wired to receive elevation.
Angle input may be in the form of either 16-bit binary angles, or four-digit
BCD. This synchronization mode is the only one which ascribes any
meaning to the TAG inputs; ordinarily they are merely passed on to the
user computer as ancillary information.
Antenna synchronization is accomplished by way of a table of trigger
angles. This table, which contains between three and 4096 angles, is used
to define the angle boundaries for each processed ray. The trigger angles
need not be uniformly spaced, nor must they span the full 360-degrees of
rotation. This gives considerable flexibility in the choice of angles. For
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
| | | | | | | | | | | | | | | | |
| Desired Trigger Generator Period (0.16667usec Increments) | Input 1
|_______________________________________________________________|
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
| | | | | | | | | | | | | | | | |
| Lower 16–Bits of 32–Bit Trigger Period in Nanoseconds | XARG 1
|_______________________________________________________________|
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
| | | | | | | | | | | | | | | | |
| Upper 16–Bits of 32–Bit Trigger Period in Nanoseconds | XARG 2
|_______________________________________________________________|
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Vaisala RVP900 Specifications

General

Brand	Vaisala
Model	RVP900
Category	Receiver
Language	English