Time Correction And Analog Demodulation - Agilent Technologies 89410A Operator's Manual

Analog Demodulation Concepts

Time Correction and Analog Demodulation

Time correction applies the correction factors which are derived during calibration.
Time calibrations are used to correct for magnitude and phase distortion in the
time record prior to the demodulation process. Left uncorrected these distortions,
which are introduced by the analog and digital filters, create errors in the
demodulated signal and also introduce cross modulation products such as
PM-to-AM conversions.
Time calibrations only correct for distortion over the selected span. Sidebands
which fall outside of the displayed span, but have not been completely attenuated
by the digital filter, are subject to severe distortion and can create errors in the
measurement. For this reason it is important that the signal reside completely
within the span and that all unwanted signals be well outside of the span. See
"Checking for interfering signals" later in this chapter.
Time correction is automatically enabled when you enter Analog Demodulation
mode, and is disabled when you return to Vector mode.
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