A Background To Return Loss Measurement With The Hp 81534A; Measuring The Reflected Power From A Component With Known Reflection Factor - Agilent Technologies 8163A User Manual

A Background to Return Loss Measurement with the HP 81534A

Agilent 8163A Lightwave Multimeter, Agilent 8164A Lightwave Measurement System, & Agilent 8166A Lightwave
Multichannel System, Fourth Edition
A Background to Return Loss
Measurement with the
HP 81534A
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 is component is called the reflection reference.
P
src
k
1
P
Ref
Figure 100 Measuring the Power from a Component with Known Reflection Factor
This measured power from the reflection reference is called P
The following two components are recommended for use as a reflection
reference:
• a Reflection Reference Cable or
• the Agilent 81000BR Back Reflector.
N O TE Note you can only measure the Front Panel Delta if you use a Reflection
Reference Cable.
The reflection factor for the component is called R
the component (RL
HP 81534A
P
in
k
2
P
r
) is specified, but these values are related:
R
RL = – 10
R
Return Loss Measurement
Reflection
Reference
Reflectivity
R
Ref
. Normally the return loss for
R
P
r
log R = – 10 log -------
R
P
in
.
Ref
145