A Reflection Measurement Of Two Cables - Agilent Technologies 8719D User Manual

Figure 6-63. A Reflection Measurement of Two Cables
The ripples in reflection coefficient versus frequency in the frequency domain measurement are
caused by the reflections at each connector "beating" against each other.
One at a time, loosen the connectors at each end of the cable and observe the response in both
the frequency domain and the time domain. The frequency domain ripples increase as each
connector is loosened, corresponding to a larger reflection adding in and out of phase with
the other reflections. The time domain responses increase as you loosen the connector that
corresponds to each response.
Interpreting the bandpass reflection response horizontal axis. In bandpass reflection
measurements, the horizontal axis represents the time it takes for an impulse launched at the
test port to reach a discontinuity and return to the test port (the two-way travel time). In
Interpreting the bandpass reflection response vertical axis. The quantity displayed on the
vertical axis depends on the selected format. The common formats are listed in 'Ihble 6-8. The
default format is LOG MAG (logarithmic magnitude), which displays the return loss in decibels
frequency range of the measurement. Use the REAL format only in low pass mode.
6 - 1 2 2 ApplicationmdOperationConwpts
NETWORK ANALYZER