800MHz Tetra BDA User Handbook For AFL Inc. AFL Works Order Nō.: AFL product part Nō.: Q112081 55-151501 800MHz Tetra Repeater User Handbook Handbook Nō.
Table of Contents AMENDMENT LIST RECORD SHEET ...................................................................................................4 INTRODUCTION.........................................................................................................................................5 Scope ........................................................................................................................................................................... 5 Purpose ..........................
6.1.1 Fault Finding............................................................................................................................................ 26 6.1.2 Downlink................................................................................................................................................... 27 6.1.3 Uplink ....................................................................................................................................................... 27 6.1.
AMENDMENT LIST RECORD SHEET Issue Nō. 1 Date 22/04/2005 Incorporated by CMH Page No.’s Amended Reason for new issue 1st Draft Document Ref:-55-151501HBK 800MHz Tetra Repeater User Handbook Handbook Nō.
INTRODUCTION Scope This handbook is for use solely with the equipment identified by the AFL Part Number shown on the front cover. It is not to be used with any other equipment unless specifically authorised by Aerial Facilities Limited. Purpose The purpose of this handbook is to provide the user/maintainer with sufficient information to service and repair the equipment to the level agreed.
Glossary of Terms Repeater or Cell Enhancer Band Selective Repeater Channel Selective Repeater BTS C/NR Downlink (D.L.) Uplink (U.L.) EMC GND DC AC ID OIP3 LED M.S. N/A N/C NF RF Rx Tx S/N A Radio Frequency (RF) amplifier which can simultaneously amplify and re-broadcast Mobile Station (MS) and Base Transceiver Station (BTS) signals. A Cell Enhancer designed for operation on a range of channels within a specified frequency band.
Key to AFL RF Module Drawing Symbols 800MHz Tetra Repeater User Handbook Handbook Nō.
1. SAFETY CONSIDERATIONS 1.1 Earthing of Equipment Cell Enhancers supplied from the mains must be connected to grounded outlets and earthed in conformity with appropriate local, national and international electricity supply and safety regulations. 1.2 Electric Shock Hazard Electrical shocks due to faulty mains driven power supplies.
1.3 RF Radiation Hazard RF radiation, (especially at UHF frequencies) arising from transmitter outputs connected to AFL’s equipment, must be considered a safety hazard. This condition might only occur in the event of cable disconnection, or because a ‘spare’ output has been left unterminated. Either of these conditions would impair the system’s efficiency. No investigation should be carried out until all RF power sources have been removed.
1.4 Chemical Hazard Beryllium Oxide, also known as Beryllium Monoxide, or Thermalox™, is sometimes used in devices within equipment produced by Aerial Facilities Ltd. Beryllium oxide dust can be toxic if inhaled, leading to chronic respiratory problems. It is harmless if ingested or by contact. Products that contain beryllium are load terminations (dummy loads) and some power amplifiers. These products can be identified by a yellow and black “skull and crossbones” danger symbol (shown above).
2. SYSTEM OVERVIEW The AFL Band Selective Cell Enhancer is a 2-way on-band repeater. Various models are available to cover frequency bands from 50MHz to 3000MHz with power levels up to 100Watts. Its main sphere of applications is in urban areas where the topology is such that shadows occur in the propagation pattern (for example within large buildings, conference centres and tunnels, etc.
3. TETRA BI-DIRECTIONAL AMPLIFIER 3.P System Photographs 800MHz Tetra Repeater User Handbook Handbook Nō.
3.1 Description The 800MHz Tetra band selective (no channelisation) tunnel amplifier is directly connected to an air interface antenna directed towards the base station and a leaky feeder antenna to cover the mobiles in the tunnel. The downlink power is 20Watts, provided by a single power amplifier, and the uplink power device is a single 5W amplifier, which is sufficient power for ample communications with the base station.
3.
BASE Handbook Nō.-55-151501HBK Issue No:-A 30dB dB 17-001109 12-018601 AGC DET 11-006702 30dB 30dB dB 30dB AGC DET 02-007206 02-007206 17-001109 10-000701 11-006702 dB 12-018002 30dB 17-001201 11-006702 30dB 11-006702 dB 10-000701 17-001201 MOBILE System Drawings 02-007206 02-007206 3.
3.5 Parts Lists AFL Part Nō.
4. SUB-UNIT MODULES 4.1 4.1.1 Bandpass Filters (02-007206) Description The bandpass filters are multi-section designs with a bandwidth dependent upon the passband frequencies, (both tuned to customer requirements). The response shape is basically Chebyshev with a passband design ripple of 0.1dB. The filters are of slot coupled, folded combline design, and are carefully aligned during manufacture in order to optimise the insertion loss, VSWR and intermodulation characteristics of the unit.
4.2 ¼Watt 0- -30dB Switched Attenuator (10-000701) 4.2.1 General Application In many practical applications for Cell Enhancers etc., the gain in each path is found to be excessive. Therefore, provision is made within the unit for the setting of attenuation in each path, to reduce the gain. 4.2.2 Switched Attenuators The AFL switched attenuators are available in two different types; 0 – 30dB in 2 dB steps (as in this case), or 0 – 15dB in 1 dB steps.
4.3 4.3.1 Low Noise Amplifier (11-006702) Description The Gallium-Arsenide low noise amplifiers used in the unit are double stage, solid-state low noise amplifiers. Class A circuitry is used throughout the units to ensure excellent linearity and extremely low noise over a very wide dynamic range. The active devices are very moderately rated to provide a long trouble-free working life.
4.4 4.4.1 20W Power Amplifier (12-018002) Description This amplifier is a Class A 20W power amplifier from 800-960MHz in a 1 stage balanced configuration. It demonstrates a very high linearity and a very good input/output return loss (RL). It has built in a Current Fault Alarm Function. Its housing is an aluminium case (Alocrom 1200 finish) with SMA connectors for the RF input/output and a D-Type connector for the power supply and the Current Fault Alarm Function. 4.4.
4.5 4.5.1 5W Power Amplifier (12-018601) Description This amplifier is a Class A 5W power amplifier from 800MHz to 960MHz in a 1 stage balanced configuration. It demonstrates a very high linearity and a very good input/output return loss (RL). It has built in a Current Fault Alarm Function. Its housing is an aluminium case (Alocrom 1200 finish) with SMA connectors for the RF input/output and a D-Type connector for the power supply and the Current Fault Alarm Function. 4.5.
4.6 4.6.1 Wide Dynamic Range AGC (17-001109, det. & 17-001201, atten.) Description The equipment is fitted with a wide dynamic range Automatic Gain Control (AGC) system. This is generally fitted in the Uplink path (not usually needed in the downlink path, as the signal here is at an almost constant level), to avoid overloading the amplifiers (with the associated performance degradation) should a mobile be operated very close to the unit.
For small signals, below AGC onset, the output control line will be close to 12V and the AGC attenuator will have minimum attenuation. As the signal level increases the control line voltage will fall, increasing the attenuator value and keeping the system output level at a constant value. The AGC onset level is adjusted by the choice of sampler resistor R1 and by the setting of potentiometer VR1, (factory set @ time of system test) do not adjust unless able to monitor subsequent RF levels.
4.8 4.8.1 15V Switch-Mode PSU (96-300054) Description The power supply unit is a switched-mode type capable of supplying 15V DC at 27Amps continuously. The amplifiers in this unit will draw approximately 17-18Amps at 12V DC, so the PSU will be used conservatively ensuring a long operational lifetime. No routine maintenance of the PSU is required. If a fault is suspected, then the output voltage from the power supply may be measured on its output terminals. This is typically set to 12.2V.
5. INSTALLATION 5.1 Initial Installation Record When this equipment is initially commissioned, please use the equipment set-up record sheet in Appendix A. This will help both the installation personnel and AFL should these figures be needed for future reference or diagnosis. 800MHz Tetra Repeater User Handbook Handbook Nō.
6. MAINTENANCE 6.1 6.1.1 General Procedures Fault Finding In the event that the performance of the system is suspect, a methodical and logical approach to the problem will reveal the cause of the difficulty. The System consists of modules within a wall mounted, environmentally protected enclosure Transmissions from the main base stations are passed though the system to the mobile radio equipment; this could be a handheld radio or a transceiver in a vehicle. This path is referred to as the downlink.
6.1.2 Downlink Confirm that there is a signal at the expected frequency and strength from the base station. If this is not present then the fault may lay outside the system. To confirm this, inject a downlink frequency signal from a known source at the master site BTS input and check for output at the remote site feeder output. If a signal is not received at the output it will be necessary to follow the downlink path through the system to find a point at which the signal is lost.
6.1.5 Checking service Following the repair of any part of the system it is recommended that a full end-to-end test is carried out in accordance with the test specification and that the coverage is checked by survey. It is important to bear in mind that the system includes a radiating cable network and base stations that may be faulty or may have been damaged. 6.1.6 Service Support Advice and assistance with maintaining and servicing this system are available by contacting Aerial Facilities Ltd. 6.
6.3 6.3.1 Care of Modules General Comments Many of the active modules contain semiconductor devices utilising MOS technology, which can be damaged by electrostatic discharge. Correct handling of such modules is mandatory to ensure their long-term reliability. To prevent damage to a module, it must be withdrawn/inserted with care. The module may have connectors on its underside, which might not be visible to the service operative. 6.3.
5) If the amplifier to be removed has a heatsink attached, there may be several different ways it can have been assembled. The most commonly used method, is screws through the front of the heatsink to threaded screw holes (or nuts and bolts), into the amplifier within the main case. If the heatsink is mounted on the rear of the main case (e.g.
APPENDIX A INITIAL EQUIPMENT SET-UP CALCULATIONS GENERAL INFORMATION Client Name: AFL Equip. Model Nō. Site Name: Date: Model ANTENNA SYSTEMS Gain Azimuth Comments Type Loss Comments A - Service Antenna B – Donor Antenna Length C – Service Feeder D – Donor Feeder INITIAL PARAMETERS E – CE Output Power F – Antenna Isolation G – Input signal level from donor BTS Operating Voltage dBm dB dBm V DOWNLINK CALCULATIONS Parameter Comments Input signal level (G) CE max.
