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Next Generation
Signal Enhancement
using some type of grounded metal screen or wire mesh (so called chicken
wire) between antennas.
The following example illustrates a typical signal level at input of the
repeater and other losses with final EIRP:
Received Signal Level
-62
dBm
Donor Antenna gain
12
dBi
Cable loss (100 ft. of 7/8 inch)
2
dB
Input to Repeater
-52
dBm
Gain of Repeater set
70
dB
Output of Repeater
+18
dBm
Cable loss (100 ft. of 7/8 inch)
2
dB
Server Antenna Gain
7
dBi
Repeater EIRP
+23
dBm
c) Overlapping Coverage
Ideally, the repeater system will be engineered with minimal overlapping
coverage between the donor base station and the repeater. However, the
mobile will occasionally receive signals from both the donor and the
repeater at similar levels. This situation is comparable to a mobile receiving
multiple signals at varying times due to multi-path propagation.
The repeater contributes a maximum signal delay of 5.5 microseconds in
each direction.
d) Call Processing
The mobile communication system perceives calls handled by the repeater
as actually being handled by the donor site (BTS); the repeater is just an
extension of the base station’s coverage. Therefore, the donor handles call
initiation, power control messages, hand-over requests, etc., for mobiles in
the repeater area. When the base station assigns a channel to the mobile,
that channel is sent through the repeater and then reradiated under the
same frequency. Since the repeater is technically part of the base station,
no hand-over takes place when a mobile moves from the repeater’s
coverage area to that of the base station. When the mobile moves from the
repeater’s area to a neighboring site, the base station handles the hand-off
in the same way as for a mobile in the base station area.
8.3. Installation Tools
You will need the following basic tools for installation:
a. Standard wrenches/screwdrivers/cable stripper/cable cutter/pliers set
for installing the DB6MR20 Unit and antennas. (Refer to the
manufacturer’s recommendations for installing the antennas).
