Agilent Technologies Measuring Electrical Length and Phase Distortion

1-43
Making Measurements
Measuring Electrical Length and Phase Distortion
Measuring Electrical Length and Phase Distortion
Electrical Length
The analyzer mathematically implements a function similar to the mechanical “line
stretchers” of earlier analyzers. This feature simulates a variable length lossless
transmission line, which you can add to or remove from the analyzer's receiver input to
compensate for interconnecting cables, etc. In this example, the electronic line stretcher
measures the electrical length of a SAW filter.
Phase Distortion
The analyzer allows you to measure the linearity of the phase shift through a device over a
range of frequencies and the analyzer can express it in two different ways:
• deviation from linear phase
• group delay
Measuring Electrical Length
1. Connect your test device as shown in Figure 1-33.
Figure 1-33 Device Connections for Measuring Electrical Length
2. Press and choose the measurement settings. For this example, the
measurement settings include reducing the frequency span to eliminate under - s ampled
phase response. Press the following keys as shown:
or on ET models:
Preset
Meas
Trans:FWD S21 ( B/R)
TRANSMISSN
Center 134 M/µ
Span 2M/µ
Format
PHASE
Scale Ref
AUTO SCALE