17
EN
The satellite band
In this example the T-100 (ref. 2141) interior/
exterior cable, and 85 m for the length of the
wire have been taken as a reference. The total
attenuation is calculated by multiplying the
attenuation/m by the length of the cable.
Frequency
(MHz)
Attenuation
(dB/m)
Total
attenuation (dB)
200
0.08
6.8
500
0.12
10.2
800
0.15
12.75
1000
0.18
15.3
1750
0.24
20.4
2050
0.27
22.95
Frequency (MHz)
Powering (dBµV)
200
80.0
500
78.5
800
78.9
1000
78.8
1750
79.5
2150
82.5
In the used cable specifications, the attenuation
per meter (dB/m), that the signal undergoes will
appear. This attenuation varies with the frequency,
growing as the frequency increases.
In the following image you can see the signal at the
input (in the terrestrial band):
The terrestrial band
- Connect the noise generator to one end of the
cable.
- Connect the field meter to the other end of the
cable, configure it in spectrum mode and select
“Full Span”. You will see that the spectrum of the
received signal is no longer flat, but that the level
decreases as the frequency increases, as shown in
the following picture:
The terrestrial band
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