A Background to Return Loss Measurement Return Loss Measurement
Agilent 8163A/B, 8164A/B & 8166A/B Mainframes, Sixth Edition 189
A Background to Return Loss
Measurement
Measuring the Reflected Power from a
Component with Known Reflection Factor
First, attach a component with a known reflection factor in place of the
DUT, and measure the power reflected. This component is called the
reflection reference.
Figure 111 Measuring the Power from a Component with a Known Reflection Factor
This measured power from the reflection reference is called P
Ref
.
The following two components are recommended for use as a reflection
reference:
• the Agilent 81610CC Reference Cable, or
• the Agilent 81000BR Back Reflector.
The reflection factor for the component is called R
R
. Normally the return
loss for the component (RL
R
) is specified, but these values are related:
Reflection
Reference
R
ref
M
ref
P
ref
Agilent 81610A
Reflectivity
P
in
P
r
You can only measure the Front Panel Delta if you use a Reflection
Reference Cable.
NOTE