Time Domain – Impulse Response - Anritsu MS2024B Manual

Time Domain, Option 2 8-3 VNA Master Implementation
Time Domain – Impulse Response
The screen capture in Figure 8-3 shows both frequency and time domain measurements of a
Beatty standard (a transmission line with a low impedance section in the middle). The left
quadrants shows the frequency response of S and S , and the right quadrants show the
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impulse response of S and S . Time domain responses offer insights about the physical
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characteristics of the DUT.
For example, in the upper right graph, the negative pulse at approximately 1.3 cm is caused
by the reflection from the 50 ohm to low-impedance step in the transmission line. A positive
pulse at approximately 6.3 cm is caused by the reflection from the low-impedance to 50 ohm
step in the transmission line. The bottom right trace shows the impulse response of S
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versus distance. A positive pulse at approximately 7.5 cm indicates the total length of the
Beatty standard. The pulse amplitude is slightly less than unity because some of the energy
from the transmitted impulse was reflected back to Port 1 (the excitation port of S
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measurements).
Figure 8-3. Beatty Standard – Frequency Response versus Impulse Response
Vector Network Analyzer MG PN: 10580-00289 Rev. K 8-5