Measuring A Device In The Time Domain (Option 010 Only); Transmission Response In Time Domain - Agilent Technologies 8719D User Manual

Measuring a Device in the Time Domain (Option 010 Only)

The HP 8719D/20D/22D Option 010 allows 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. The analyzer
measures the frequency response of your device and uses an inverse Fourier transform to
convert the data to the time domain.
Gating
Time domain analysis allows you to mathematically remove individual parts of the time domain
response to see the effect of potential design changes. You can accomplish this by "gating" out
the undesirable responses.
This section shows you how to use the time domain function to measure a device response by
the following measurement examples:
transmission measurement of RF crosstalk and multi-path signal through a surface acoustic
n
wave (SAW) alter
reflection measurement that locates reflections along a terminated transmission line
n

Transmission Response in Time Domain

In this example measurement there are three components of the transmission response:
the main travel path through the device (1.6 ps travel time)
n
the "triple travel" path (4.8 ps travel time)
n
This example procedure also shows you how time domain analysis allows you to mathematically
remove individual parts of the time domain response to see the effect of potential design
changes This is accomplished by "gating" out the undesirable responses. With the "gating"
capability, the analyzer time domain allows you perform "what if" analysis by mathematically
removing selected reflections and seeing the effect in the frequency domain.
1. Connect the device as shown in Figure 2-58.
Figure 2-58. Device Connections for !l!ime Domain Transmission Example Measurement
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