APPENDICES Page
64
Document id: 7000 108-011 A2
APPENDIX A.5 – GPS-CABLE SELECTOR
The table below gives recommendation on cables that can be used
for the GPS-antenna connections. Due to the high frequency it’s
important that the attenuation in the cable is low for the specific
frequency (1.5 GHz).
Type
Attenuation @ 1.5
GHz (dB/m)
∅
(mm)
Weight (kg/100m)
RG 400
0.6
4.95
6.3
RG 223
0.6
5.40
5.5
RG 214
0.35
10.8
18.5
RG 225
0.3
10.9
23.3
For optimum performance of the transponder approxi10dB
gain should be available when the cable attenuation has been
subtracted from the GPS-antenna preamplifier gain.
Example:
Cable type
Preamplifier
Gain (dB)
Recommended min
cable length (m)
Recommended max.
cable length (m)
RG 223
12
0
20
RG 223
26
20
45
RG 223
36
45
60
RG 214
12
0
35
RG 214
26
35
70
RG 214
36
70
100
Min. length = (Preamp. Gain – 10 dB)/Cable attenuation per meter
Max length = Preamp. Gain/Cable attenuation per meter
