Agilent Technologies 20ET ユーザーズマニュアル
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Making Time Domain Measurements
Introduction to Time Domain Measurements
Introduction to Time Domain Measurements
The analyzers with Option 010 allow you to measure the time domain response of a device.
Time domain analysis is useful for isolating a device problem in time or in distance. Time
and distance are related by the velocity factor of your device under test (DUT) which is
described in
Time domain analysis is useful for isolating a device problem in time or in distance. Time
and distance are related by the velocity factor of your device under test (DUT) which is
described in
The analyzer measures the frequency response of your device and uses an inverse Fourier
transform (a mathematical calculation) to convert the frequency domain information into
the time domain, with time as the horizontal display axis. The analyzer’s internal
computer makes this mathematical calculation using the chirp-Z Fourier transform
technique.
transform (a mathematical calculation) to convert the frequency domain information into
the time domain, with time as the horizontal display axis. The analyzer’s internal
computer makes this mathematical calculation using the chirp-Z Fourier transform
technique.
The resulting measurement is the fully error-corrected time domain reflection or
transmission response of the test device, displayed in near real-time. Response values
(measured on the vertical axis) now appear separated in time or distance, providing
valuable insight into the behavior of the test device beyond simple frequency
characteristics.
transmission response of the test device, displayed in near real-time. Response values
(measured on the vertical axis) now appear separated in time or distance, providing
valuable insight into the behavior of the test device beyond simple frequency
characteristics.
With Option 010, the analyzer can transform frequency domain data to the time domain or
time domain data to the frequency domain.
time domain data to the frequency domain.
NOTE
The analyzer can be ordered with Option 010, or the option can be added at a
later date.
later date.
The transform used by the analyzer resembles time domain reflectometry (TDR)
measurements. TDR measurements, however, are made by launching an impulse or step
into the test device and observing the response in time with a receiver similar to an
oscilloscope. In contrast, the analyzer makes swept frequency response measurements,
and mathematically transforms the data into a TDR-like display.
measurements. TDR measurements, however, are made by launching an impulse or step
into the test device and observing the response in time with a receiver similar to an
oscilloscope. In contrast, the analyzer makes swept frequency response measurements,
and mathematically transforms the data into a TDR-like display.
illustrates the frequency and time domain reflection responses of a test device.
The frequency domain reflection measurement is the composite of all the signals reflected
by the discontinuities present in the test device over the measured frequency range.
by the discontinuities present in the test device over the measured frequency range.