User Manual
Table Of Contents
- 1. INTRODUCTION
- 1.1. Scope and Purpose of Document
- 1.2. Limitation of Liability Notice
- 2. SAFETY CONSIDERATIONS
- 3. EQUIPMENT OVERVIEW
- 4. UHF BANDSELECTIVE, BDA (55-199102) SUB MODULES
- 4.1. Bandpass Filter (02-010701)
- 4.2. 3dB Splitter/Combiner (05-002603)
- 4.3. Remote Attenuator Switch Assembly (‘10-001725’)
- 4.4. 5 Watt Tetra Amplifier (12-021601)
- 4.5. Linearised Power Amplifier (12-026901)
- _
- 4.6. Voltage Regulator Board 9.0V (13-001714)
- 4.7. DC/DC Converter, 24V in, 12V 8A out (13-003011)
- 4.8. Bi-Directional Amplifier (17-017301)
- 4.9. 12V (Single) Relay Board (80-008901)
- 4.10. 24V Switch-Mode PSU (96-300054)
- 5. INSTALLATION & COMMISIONING
- 6. FAULT FINDING / MAINTENANCE
- 6.1. Tools & Test Equipment
- 6.2. Basic Fault Finding
- 6.3. Quick Fault Checklist
- 6.4. Downlink
- 6.5. Uplink
- 6.6. Fault repair
- 6.7. Service Support
- 6.8. Care of Modules
- 6.9. Module Removal (LNAs, general procedure):
- 6.10. Module Replacement (general):
- 6.11. Power Amplifiers
- 6.12. Low Power Amplifier Replacement
- 6.13. Module Transportation:
- APPENDIX A
- _
- _
- APPENDIX B
5. INSTALLATION & COMMISIONING
5.1. Antenna Installation & Gain Calculations
1 Most Cell Enhancer require two antennas, one a highly directional Yagi or similar directed
towards the donor cell base station, and one a leaky feeder, omni-directional antenna or Yagi to cover
the area in which the mobiles are to be served.
2 The maximum gain at which the Cell Enhancer can be set is limited by the isolation that can
be achieved between these two antennas. Therefore when the antennas have been installed, inject a
signal (at a known power level) into one of them and measure the signal level received by the other
antenna on a spectrum analyser. The isolation can then be calculated as the difference between
these two figures. The gain in each path of the Cell Enhancer should be set at least 10 dB below this
figure, using attenuators as described below in paragraph 5.
3 Also measure the received signal from the donor cell at the input to the Cell Enhancer (base
port). The gain of the Cell Enhancer downlink path should be set such the donor site will not overload
the Cell Enhancer amplifiers. It is recommended that the input level should be less than -50dBm at
the input of the Cell Enhancer (Base Port). (This figure is assuming maximum gain, and may be
increased by the value of the attenuator fitted in the downlink path.)
4 Ensure that the mobile facing antenna has at least 70 dB isolation from the nearest mobile.
(This is usually easily achieved when using a leaky feeder.)
5 The Cell Enhancer gain is set by setting the attenuation in each path (uplink and downlink)
between the first two amplifier stages (see markings within the Cell Enhancer or layout drawings for
the exact attenuator locations). Note that the uplink (mobile to base) and downlink (base to mobile)
path gains are set independently. This allows the paths to have different gains if required to set the
correct output power levels.
6 It is recommended that the gains are set such that the Downlink output levels from the Cell
Enhancer are typically +44dBm. (Input level + Gain = Output level).
5.2. Initial Installation Record
When this equipment is initially commissioned, please use the equipment set-up record sheet in
Appendix B This will help both the installation personnel and AFL should these figures be needed for
future reference or diagnosis.
UHF Bandselective BDA
90dB 40/5W
Document Number 55-199102HBKM Issue No. 1 Page 19 of 28