Agilent Technologies E8257D, Руководство пользователя

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8 Chapter 1
Signal Generator Overview
Modes of Operation
Analog Modulation
In this mode, the signal generator modulates a CW signal with an analog signal. The analog
modulation types available depend on the installed options.
Option UNT provides amplitude, frequency, and phase modulations. Some of these modulations can be
used together. Options UNU and UNW provide standard and narrow pulse modulation capability,
respectively. Option UNU is standard on the E8663D.
Option 1SM provides improved Exponential (Log) AM mode.
Digital Modulation
In this mode, the signal generator modulates a CW signal with either a real–time I/Q signal or
arbitrary I/Q waveform. I/Q modulation is only available on the E8267D. An internal baseband
generator (Option 601/602) adds the following digital modulation formats:
• Custom Arb Waveform Generator mode can produce a single–modulated carrier or
multiple–modulated carriers. Each modulated carrier waveform must be calculated and generated
before it can be output; this signal generation occurs on the internal baseband generator. Once a
waveform has been created, it can be stored and recalled, which enables repeatable playback of
test signals. To learn more, refer to
“Custom Arb Waveform Generator” on page 159 .
• Custom Real Time I/Q Baseband mode produces a single carrier, but it can be modulated with
real–time data that allows real–time control over all of the parameters that affect the signal. The
single–carrier signal that is produced can be modified by applying various data patterns, filters,
symbol rates, modulation types, and burst shapes. To learn more, refer to
“Custom Real Time I/Q
Baseband” on page 181 .
• Two Tone mode produces two separate continuous wave signals (or tones). The frequency spacing
between the two signals and the amplitudes are adjustable. To learn more, refer to “ Two–Tone
Waveform Generator” on page 231 .
• Multitone mode produces up to 64 continuous wave signals (or tones). Like Two Tone mode, the
frequency spacing between the signals and the amplitudes are adjustable. To learn more, refer to
“Multitone Waveform Generator” on page 221 .
• Dual ARB mode is used to control the playback sequence of waveform segments that have been
written into the ARB memory located on the internal baseband generator. These waveforms can
be generated by the internal baseband generator using the Custom Arb Waveform Generator
mode, or downloaded through a remote interface into the ARB memory. To learn more, refer to
“Using the Dual ARB Waveform Player” on page 91 .