User Manual
Table Of Contents
- Front Page
- Pretext
- Contents
- Figures
- Abbreviations
- 1. Safety
- 2. Introduction
- 3. Installation
- 4. Commissioning
- 5. Functional Description
- Repeater Design
- Block Diagram
- Board and Unit Descriptions
- DC - Directional Coupler
- DPX - Duplex Filter
- LNA - Low Noise Amplifier
- CHA - Channel Amplifier Board for Channel Selective Operation
- CSA and PA Boards for Channel Selective CDMA Operation
- BSA and PA Boards for Band Selective Operation
- DIA Board
- CU Control Unit Board
- Repeater CU Software and Hardware Compatibility
- Cabling
- 6. Optionals
- 7. Repeater Alarms
- Index
- Questionnaire
The first mixer stage on the BSA amplifier board, which is controlled by a
synthesizer, converts the received frequency down to the IF frequency.
The signal is then filtered by SAW bandpass filters and, not shown in the
figure, amplified before it is fed to the second mixer stage for conversion
back to the original frequency.
The SAW filter can be either fixed or adjustable depending on the BSA
board used. If the BSA board has fixed band width, this SAW filter is
fixed and selected for the current band width. If the BSA board has
adjustable band width, the SAW filter combination can be software
changed from within OMT32 (or OMS) to cover various band widths.
The following power amplifier is controlled by the CU. The amplifier gain
will be reduced to avoid instability due to poor antenna isolation.
A detector on the PA board measures continuously the output level. The
signal from this detector is used by the automatic gain control, AGC, to
supervise and, if necessary, reduce the output power to keep it under a
maximum level. The AGC gain control affects several of the amplification
stages.
The output signal passes duplex filter (DPX) and a directional coupler
(DC) before it is fed to the repeater MS antenna.
RCU
The optional RCU Remote Communication Unit is located inside the
repeater (described in Chapter 6, Optionals).
Communication with the base station is performed by means of a built-in
mobile feature that has the antenna connected to the BS directional
coupler (DC). Data is transferred between the repeater and the built-in
RCU unit via the P32 modem port.
The RCU unit is powered via the P27 auxiliary port and the unit has a
battery with capacity to send a number of alarms if a mains power failure
occurs.
R2R
The Repeater to Repeater Link feature makes it possible to communicate
with a number of repeaters via one RCU unit in one of the repeaters in
an R2R net. Several RCU units can also be used in the same net.
The repeaters in the R2R net are connected to the P34 port.
The R2R feature is described in Chapter 6, Optionals.
ALLGON System AB AR Repeaters Functional Description
User’s Manual VD203 66/EN Rev. P1A 2000-09 5 - 15