Anritsu MG369 C Series, Руководство по программированию

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Programming with GPIB Commands 2-9 Modulation Commands
MG369xC GPIB PM PN: 10370-10374 Rev. F 2-25
Pulse Modulation
Two pulse modulation modes are available—Internal and External. In Internal mode, pulse modulation of the
output signal is accomplished by using a modulating signal from the internal pulse generator. In External
mode, pulse modulation of the output signal is achieved using a modulating signal from an external source.
The internal pulse generator has four pulse modes —single, doublet (double pulse), triplet (triple pulse), and
quadruplet (quadruple pulse). Individual pulse widths and delays can be set for each of the pulses in a mode.
The pulse generator has two clock rates—100 MHz (or 40 MHz with Option 24) and 10 MHz. The 100 MHz
clock rate produces higher resolution pulses and allows higher PRFs; the 10 MHz clock rate produces lower
resolution pulses and lower PRFs.
The internal pulse generator can be internally triggered, externally triggered, internally and externally
triggered with delay, and gated. There is also a composite trigger mode in which an external pulse is summed
with the internal pulse to pulse modulate the output signal. (Refer to Chapter 3 of the Operation Manual for a
description of each trigger mode. )
Internal Pulse Modulation Function
The
IP
command turns on the internal pulse modulation function. The internal pulse mode is selected using
the
PMD(x)
command and the internal pulse trigger is selected using the
PTG(x)
command. The pulse period
can be set using the
PER
parameter entry command; the pulse frequency can be set using the
PR
parameter
entry command. Individual pulse widths can be set using the
W1
(or
PW
),
W2
,
W3
, and
W4
parameter entry
commands. Individual pulse delays can be set using the
D1
(or
PDY
),
D2
,
D3
, and
D4
parameter entry
commands. The
P0
(or
SW0
) command turns off the pulse modulation function.
Square wave pulse modulation of the output signal by one of four internal modulating signals is available
using the following commands:
•
SW1
turns on square wave pulse modulation at 400 Hz
•
SW2
(or
SQP
) turns on square wave pulse modulation at 1 kHz
•
SW3
turns on square wave pulse modulation at 7.8125 kHz
•
SW4
turns on square wave pulse modulation at 27.8 kHz
Programming Example:
Programming “
IP PC4 PMD2 PTG1 PER 1 MS W1 2.5 US D2 10 US W2 2 US
” turns on the internal pulse
modulation function; selects the 100 MHz (40 MHz with Option 24) pulse clock rate, doublet pulse mode, and
free run trigger mode; and sets the pulse period to 1 ms, pulse width1 to 2.5

s, delay2 to 10

s, and pulse
width2 to 2

s.
Note
At a 100 MHz pulse clock rate, the pulse period must be 50 ns longer than the pulse delays;
at a 40 MHz pulse clock rate, the pulse period must be 125 ns longer than the pulse delays;
at a 10 MHz pulse clock rate, the pulse period must be 500 ns longer than the pulse delays.
Note
Use the
EP0
and
EP1
commands to select the polarity of the signal (TTL-low or TTL-high) that turns
the RF on during pulse modulation.