Agilent Technologies 8719D, User Manual

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6-8. Time Domain Reflection Formats
Reflection (unitless) (0 1)
REAL Reflection (-1 1)
LOGMAG Return
Standing Wave Ratio (unitless)
Transmission Measurements Using Mode
The mode can also transform transmission measurements to the time domain. For
example, this mode can provide information about a surface acoustic wave (SAW) that
is not apparent in the frequency domain. Figure 6-64 illustrates a time domain
measurement of a 321 MHz SAW lllter.
Figure 6-64. Transmission Measurement in Time Domain Mode
Interpreting the transmission response horizontal axis.
In time domain
transmission measurements, the horizontal axis is displayed in units of time. The time axis
indicates the propagation delay through the device. Note that in time transmission
measurements, the value displayed is the actual delay (not The marker provides the
propagation delay in both time and distance.
Marker 2 in Figure
indicates the main path response through the test device, which
has a propagation delay of 655.6 ns, or about 196.5 meters in electrical length. Marker 4 in
Figure indicates the triple-travel path response at 1.91 or about 573.5 meters The
response at marker 1 (at 0 seconds) is an RF feedthru leakage path. In addition to the triple
travel path response, there are several other multi-path responses through the test device,
which are inherent in the design of a SAW
Interpreting the transmission response vertical
axis. In the log magnitude
format, the vertical displays the transmission loss or gain in in the linear magnitude
format it displays the transmission coefficient Think of this as an average of the
response over the measurement frequency range.
Application and Operation Concepts