Roger GPSR-BP, Как пользоваться инструкцией

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What to consider when planning a ROGER GPS Repeater installation
1. Distance between the outdoor antenna and the repeater.
The Roger GPS repeater system needs ~ 15 dB RF gain from the antenna includ-
ing cable losses for best performance. The antenna supplied with the basic repeater
package has an RF gain of 35 dB, which results in a cable loss budget of approxi-
mately -20 dB. Using an RG-58/RG-223 cable to connect the antenna therefore limits
the distance between the antenna and the repeater to ~ 30 m as the typical loss of a
RG-58 cable is ~ 0,65 dB/m @ 1575 MHz. If the distance between the outdoor
antenna and the repeater requires longer cable runs different methods can be used.
a) Use a lower loss cable.
Using RG214/RG213 cable will allow a cable run of 65 - 70 meters, as the typical
attenuation for this cable is ~ 0,3 dB/m @ 1575 MHz
b) Use a Line Amplifier to compensate cable losses.
Connecting the ROGER Line Amplifier between the antenna and the repeater provides
an addi18dB gain, which increases the allowed cable length to 58 m with RG-
58/RG-223 cable and 125 m with RG214/RG213 cable. The ROGER Line Amplifier
should be placed as close as possible to the outdoor antenna and as it is powered by
the ROGER GPSR-1 repeater through the coaxial cable, no separate power
line connection is required. Two ROGER Line Amplifiers can be connected in series,
increasing the maximum cable length to ~ 180 m using RG-214/RG-213 and ~ 85 m
using RG-58/RG-223 cable.
2. Area to be covered by the repeater.
The area covered by the repeater typically has a radius of 10 - 15 m. This means that
for some installations, like in parking houses or garages, multiple repeaters will be
needed to provide the desired coverage.
In this example five repeaters and a 1:5 Signal Splitter are used to cover the area of a
garage. The ROGER Signal Splitter allows up to 5 repeaters to be connected to one
receive antenna. One splitter output is DC-coupled, has -4 dB coupling loss and must
always be connected to a repeater to allow DC to be fed to the receive antenna and /
or line amplifier. The four remaining outputs are DC-blocked, have -12 dB coupling
loss and should be terminated if not used. To cover bigger areas, additional signal
splitters can be connected in a chain configuration using the DC-coupled output.
Important!
In applications using multiple repeaters, the loss budget for each repeater must be
calculated to make sure – 20 dB of link loss is not exceeded.
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