Vaisala RVP900 - Page 126

Configuring a pulse configuration for a hybrid pulse here. In a hybrid pulse, a long
compressed pulse is followed immediately by a shorter (usually fixed frequency) pulse. Data
from the second shorter pulse is used for near ranges, while the longer pulse is used for
farther ranges. Specify the index number of the second pulse (origin 0). Use -1 to mean no
second pulse. You configure the second pulse separately using a dierent Mt <n>
commands.
Check this transmit pulse timing oset in the Pb plot by making sure that the Tx burst is
centered within the FIR data window.
Hybrid pulse chained PW index
RVP900 uses 3 real–valued tuning parameters to make the synthesis of complex waveforms
more
flexible. You can alter and fine-tune each waveform class up to 3° of freedom, making
it possible for a single class (for example, the non–linear FM class) to generate a huge
variety of waveforms. These adjustable constants also form the basis of the automatic
waveform optimization procedure for the Pa command. See 6.8.2 Available Subcommands
In Pa (page 162).
Each parameter has a minimum value, a maximum value, and a current value, which can be
changed from this menu. The Min/Max limits are used in the Pa command to maintain
sensible bounds as the parameters are adjusted. The Min/Max values are usually entered
from the Mt<n> menu, but the values can be tuned using either manual or automatic
procedures in the Pa command.
CWPulse Class
The CWPulse class of waveforms do not use the tuning parameters because the Tx
waveform is determined by the desired bandwidth and pulse width, that is, there are no
remaining degrees of freedom to adjust. These questions do not appear in the CWPulse
case.
TxWave MIN tuning params: 0.0000, 0.0000, 0.0000
TxWave MAX tuning params: 1.0000, 1.0000, 1.0000
TxWave tuning parameters: 0.9500, 1.0000, 0.0490
Linear and Non-Linear FM Class
The linear FM class is specified by the bandwidth and pulse width values, and does not
reference any tuning parameter.
The non–linear FM class is the most flexible of all, and references all three tuning parameters
as follows:
RVP900 User Guide M211322EN-J
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