R
R
F
F
-
-
7
7
0
0
0
0
0
0
E
E
M
M
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i
c
c
r
r
o
o
w
w
a
a
v
v
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RF-7000E Operations Manual
Chapter 3. Mounting the Antennas
— 49
CA
SA
WAVEGUIDE
FEEDLINES
EAST
ANTENNA
WEST
ANTENNA
SPECTRUM
ANALYZER
SIGNAL
GENERATOR
CA
SG
Figure 22 Antenna Isolation Measurement - Equipment Configuration
NOTE:
In all cases, measure antenna isolation with all feedlines, jumpers, cables, and connectors in
place. Record all measurements for future reference.
The equation for antenna isolation measurement is:
ISO = P
GEN
– (L
C-GEN
+ L
C-SA
) - P
SA
Where:
ISO
= Isolation in dB between the antennas.
P
GEN
= Output level of the signal generator (dBm).
L
C-GEN
= Loss of the signal generator cable, CA
SG
(dB).
L
C-SA
= Loss of the spectrum analyzer cable, CA
SA
(dB).
P
SA
= Power indicated on the spectrum analyzer (dBm).
For example:
P
GEN
= 10 dBm
L
C-GEN
= 1.0 dB
L
C-SA
= 1.0 dB
P
SA
= -92 dBm
ISO
= 10 dBm
– (1 dB + 1 dB) – (-92 dBm) = 100 dB