Operation & Maintenance Manual

TELCOSAT RPT 700
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Document use is restricted to that described on the cover
Downlink Signal From the Remote Cell Tower to the Cell Phones
Downlink RF signals from a donor cell site are received by the pick-up antenna connected to the
repeater. This signal is then passed through a Diplexer. The RF output from the diplexer is then
passed through a signal filter chain to reject out-of-band Inter Modulation products and
unwanted radio signals. The cleaned signal is finally amplified in the down link amplifier
module and injected into the area fill antenna for full-area coverage.
Uplink Signal from the Cell Phones to the Cell Tower
The Up-link signals from cell phones are received at the area fill antenna of the repeater. The
incoming signal then passes through a Diplexer. The RF output of the diplexer is then passed
through a filter chain to remove unwanted signals. The RF output of the filter chain and is then
amplified in the Up-link power amplifier.
2.1.2 RPT 700 Functional Description
The Up-link RF path is isolated from the Down-link RF path by utilizing Cavity Band Pass
Diplexers and Saw Band-pass filters (BPF) which provide out-of-band rejection.
Downlink Signal Path
An RF signal from the remote cell tower is picked up by a donor antenna connected to the
RPT700 “N” Type donor antenna port. The signal passes through a multiplexer and then into a
Phase Lock Loop (PLL) controller where unwanted signals are removed. The cleaned RF signal
leaves the PLL and is amplified by an onboard Power Amplifier. The amplified RF signal then
passes through another multiplexer and out to the area fill antenna via an “N” Type connector
port on the RPT700. A suitable antenna connected to Area Fill port then broadcasts the amplified
signal around the local area site and the cell phones.
Uplink Signal Path
An RF signal from the local cell phone(s) is picked up by the area fill antenna connected to the
RPT700 “N” Type area fill antenna port. The signal passes through a multiplexer. For a dual
band system the multiplexer isolates the two frequency bands, band 12 and band 13 and each
band is passed to separate PLL’s according to the specific frequency band. After the PLL has
removed any unwanted signals the cleaned RF signal is amplified by an onboard frequency
dependent Power Amplifier. The amplified RF signal then passes through another multiplexer
and out to the Donor antenna via an “N” Type connector port on the RPT700. A suitable antenna
connected to Donor port then broadcasts the amplified signal back to the remote cell tower.