Product specifications

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In pulse-to-pulse measurements, PRI has to be wide enough for the PNA-X to
keep up with the data acquisition from one pulse to the next. The minimum PRI
becomes slightly longer with narrower IF bandwidth as the data acquisition time
becomes longer. Table 2 is the minimum PRI by IF bandwidth for 26.5 GHz PNA-X
with DSP version 4 and 1.5 GHz CPU board as a reference. The minimum PRI
could be improved as the data processing time becomes shorter with a faster
CPU and/or DSP.
Table 2. Minimum PRI in wideband pulse-to-pulse measurement
IF bandwidth (kHz)
Minimum PRI in wideband pulse-to-pulse
measurements (us)
100 47
150 43
200 41
280 40
360 39
600 37
1000 36
1500 34
2000 34
3000 33
5000 32
If the data acquisition process is not ready when the second pulse comes, it waits
for the next pulse to take data for the second data point. Thus the missing pulses
cannot be easily seen in pulse-to-pulse measurements. To verify every single pulse
is measured in a particular setup, an oscilloscope may be used to compare the
PNA-X’s AUX trigger output to the pulse trigger. Figure 15 shows the setup and the
screen shots from the oscilloscope for every pulse and missing pulses.
Figure 15. Wideband pulse-to-pulse measurement verification