Return Loss Measurement A Background to Return Loss Measurement
196 Agilent 8163A/B, 8164A/B & 8166A/B Mainframes, Sixth Edition
If we divide equation 11 by equation 12, this gives the following equation:
The loss variation, ∆L, due to exchanging the reference cable for the
measurement cable is given by:
When you enter a value for the Front Panel Delta, <FPDelta>, the
instrument automatically performs the following calculation:
Calculating the Insertion Loss of the DUT
Insertion Loss is explained in “What is Insertion Loss?” on page 165.
To measure the insertion loss you must measure the power transmitted
through the measurement cable, see “Measuring the Power Transmitted
Through the Measurement Patchcord” on page 191 and the power
transmitted through the DUT, see “Measuring the Power Transmitted
Through the DUT” on page 192.
The equation below gives the insertion loss of the DUT, IL
DUT
:
E
Ref
E
Meas
---- ----- ---- ---
a
Ref
a
Meas
----- ---- ---- ---=
(15)
(16)
RL RL
DUT
2∆L+=
(17)
(18)