Pendulum CNT-90 Series User Manual

Pulsed Signals
[CNT-90 XL option 28 only]
I NTRODUCTION
The option 28, named Pulsed RF option, allows the CNT-90XL
counter to measure pulsed RF signal characteristics. A pulsed signal
can be defined by some parameters, as described below.
Frequency in pulse (FP): also known as carrier frequency or
frequency in burst is the signal frequency within the pulse.
Pulse Width (PW): it is the pulse duration.
Pulse Repetition Interval (PRI): it is the pulse period of repetition.
Pulse Repetition Frequency (PRF): it is the reciprocal of the PRI.
Pulse Power level (P
on
) is the signal level and is showed in dBm.
S ETTINGS
To be able to measure pulsed signal main characteristics, the
CNT-90XL option 28 has a special set of measurement settings.
Start Delay: internal signals may need some time to be properly
established. Start delay is useful to skip initial signal transient
response to make sure that measurement starts when signal is stable.
Measurement time is the time during which the measurement is
actually done. NOTE that measurement time must be shorter than the
pulse width with some margin.
Pulse Sensitivity setting ; High/Medium/Low, corresponds to the
trigger level selected for the internal pulse envelope detector signal.
This setting depends on the RF signal power level.
RECOMMENDED S ETTINGS
In most cases, best values to use for start delay and measurement
time are respectively 10% and 80% of pulse width.
NOTE: Measurement time should end min. 40 ns before end of pulse!
Example: For a 100ns pulse, the recommended start delay is 10 ns
and Meas. Time is 50ns
Sensitivity
P
on
< -8dBm
HIGH sensitivity
-8dBm < P
on
< -3dBm MEDIUM sensitivity
P
on
> -3dBm LOW sensitivity
settings:
NEEDED S ETTINGS
Depending on selected measurement, some parameters need to be
properly defined to get a correct result. The following table
summarizes needed settings for each measurement function.
Manual Acq & Center freq. Start Delay Measurement Time Sensitivity
Frequency in Pulse X X X X
Pulse Width X X
Pulse repetition interval X X
Power in pulse X X X
4-29
USER MANUAL ● CNT 9x Series ● Rev.22 February 2020
Measuring Functions

Pendulum CNT-90 Series Specifications

General

Brand	Pendulum
Model	CNT-90 Series
Category	Measuring Instruments
Language	English