Vaisala RVP900, User Manual

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A standard output is the
I
/
Q
time series on gigabit network (1000 BaseT). These are sent
using UDP broadcast to an
I
/
Q
archiving system or an independent parallel processing
system.
More Information
‣
Host Computer Command Overview (page 235)
3.4 Radar Control Functions
Table 10 Radar Control Functions
Function Description
Trigger generation Up to 12 programmable triggers.
Pulse width control Four states controlled by 4 bits.
Angle/data
synchronization Used to collect data at precise azimuth intervals (for example, every 0.5°, 1°, 1.5°)
based on the
AZ / EL angle inputs.
Phase shifter Used to control the phase on legacy Klystron systems.
New or upgraded Klystron or TWT systems can use the RVP900/Tx card to
provide accurate phase shifting.
Z
dr
switch control For horizontal/vertical or other polarization switching scheme.
AFC digital output Based on the burst pulse analysis for magnetron systems
Pulse Width and Trigger Control
Four TTL output lines can be programmed to drive external relays that control the
transmitter pulse width.
The internal trigger generator drives 8 separate lines - each can be programmed to produce
a desired waveform. The waveforms are stored in RAM, and can be modified interactively by
the software.
Precisely delayed and jitter-free strobes and gates can be easily produced. For each pulse
width, there is a corresponding maximum trigger rate that can be generated. The processor
measures the trigger period between pulses, so that user software can monitor it as needed.
RVP900 can also operate from an external user-supplied trigger.
Trigger Blanking
In trigger blanking, one or more (selectable) of the transmit triggers can be inhibited. Using
one of the following techniques, trigger blanking is used to avoid interference with other
electronic equipment and to protect nearby personnel from radiation hazard:
• 2D AZ/EL sector blanking areas can be defined in RVP900
• An external trigger blanking signal (switch closure to ground, TTL, or RS422) can be
supplied, for example, from a proximity switch that triggers when the antenna goes
below a safe elevation angle or connected to the radome access hatch
RVP900 User Guide M211322EN-J
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