INSTALLATION AND OPERATING MANUAL FOR BDA-CELLAB-2/25W-90-OA INDOOR REPEATER
TABLE OF CONTENTS PARAGRAPH PAGE NO BDA OVERVIEW BDA BLOCK DIAGRAM DESCRIPTION OPTIONAL EQUIPMENT OVERVIEW BDA BLOCK DIAGRAM DRAWING (Figure 1) ELECTRICAL SPECIFICATIONS MECHANICAL SPECIFICATIONS ENVIRONMENTAL CONDITIONS BDA CONNECTIONS OPTIONAL EQUIPMENT OVERVIEW MECHANICAL OUTLINE DRAWING (Figure 2 & 2a) OPTIONAL BATTERY BACK-UP CONFIGUATION (Figure 3) BDA INSTALLATION RF EXPOSURE WARNING BDA OPERATION INTERNAL VIEW (Figure 4) CONTROL PANEL ADJUSTMENT (Figure 5) DIAGNOSTICS GUIDE Page 2 3 3 3 4 5 6 6
BDA OVERVIEW: The BDA assembly extends the coverage area of radio communications in buildings and RF shielded environments. The unit features low noise figure and wide dynamic range. It is based on a duplexed path configuration with sharp out of band attenuation allowing improved isolation between the receiving and transmitting paths. The BDA supports modulation types CDMA and GSM. BDA CIRCUIT DESCRIPTION: Refer to figure 1 for the following discussion.
Figure 1 1. 2. 3. 6. 7. 4. 5. BDA Block Diagram 1. Uplink Diplexer - has low bandpass insertion loss and high selectivity 2. Downlink Pre-amp - is a low noise amplifier that drives the Downlink PA and offers 46dB Gain 3. Downlink PA – is a power amplifier with an ALC circuit which offers 43dB Gain 4. Uplink MPA – is a medium power amplifier with an ALC circuit which offers 43dB Gain 5. Uplink Pre-amp - is a low noise amplifier that drives the Uplink MPA and offers 46dB Gain 6.
ELECTRICAL SPECIFICATIONS: Frequency Range Uplink Downlink : 824-849 MHz : 869-894 MHz Pass Band Gain @ min attenuation : 95 dB (Typ.) Variable Step Attenuator Range (2-dB steps) : 0-30 dB Pass band Ripple : ±1.5 dB (typ) 20 dB Bandwidth : 30 MHz (Max.) Noise Figure @+25°C at max gain : 4.0 dB max.
MECHANICAL SPECIFICATIONS: Size : 16.0 x 12.0 x 8.75 inch (406 x 305 x 222 mm) Weight : 35 Lbs. (16.0kg.) approx. ENVIRONMENTAL CONDITIONS: The unit is designed for indoor applications: Operating temperature: -30°C to + 65°C Storage temperature: - 50°C to + 90°C BDA CONNECTIONS The BDA AC power is accepted through a 3-wire male plug with phase, neutral and ground leads. The AC power is wired to a high efficiency DC switching power supply which is CE and UL approved.
OPTIONAL EQUIPMENT OVERVIEW: a.) Uninterruptible Power System (UPS) Option An optional UPS is offered for systems that need emergency back-up power. The system can easily be connected to a battery for uninterruptible operation. Not only does the power supply power the load, but it also charges the battery. If the AC power fails, the battery will uphold the load. Batteries can be supplied upon request or a conventional battery configuration can be used (See Figure 3). b.
Figure 2 Optional Connectors BDA Mechanical Outline Figure 2a Optional Alarm Conditions The alarm monitors current of both uplink and downlink amplifiers. An alarm condition will occur if either uplink or downlink amplifiers are over or under its current tolerance or if there is no DC power present.
Figure 3 Optional Battery Back-Up Configuration 15 Amp Fuse + + - - 12 Volt 12 Volt Lead-Acid Lead-Acid Battery Battery 15 Amp - - + Battery of BDA Battery Back-Up Time Recommend Battery Rated Capacity (20 Hour Rate) Typical Current Rating for BDA-XXXX1/25W-88 1 Hour 2 Hours 3 Hours 5 Hours 7 Hours 7.2 Amp Hours 12 Amp Hours 17 Amp Hours 28 Amp Hours 42 Amp Hours 3.5 Amps 3.5 Amps 3.5 Amps 3.5 Amps 3.5 Amps Note: We do not guarantee specifications under Battery Back-Up power.
BDA INSTALLATION PROCEDURE IMPORTANT: DO NOT APPLY A.C. OR DC POWER TO THE BDA UNTIL CABLES ARE CONNECTED TO BOTH PORTS OF THE BDA AND THE ANTENNAS. 1. Mount the BDA on the structure with the RF connectors pointing DOWN. Using appropriate screws and anchors, attach the BDA to the structure using the six mounting holes on the side flanges. 2. Ensure that the isolation between the donor antenna and the service antenna is at least 12 dB greater than the BDA gain.
BDA OPERATION Variable Step Attenuator BDA gain can be reduced by up to 30 dB in 2 dB steps using the variable step attenuator (Figure 3). Gain adjustment is made with rotary switches accessible via the access door on the BDA enclosure. Arrows on the shafts of these switches point to the value of attenuation selected. BDA gain can be determined by subtracting the attenuation value from the gain reported on the BDA Test Data Sheet for that side of the unit.
Figure 4 Internal View Down-Link HPA Protected for Temperature Protected for Overload ALC circuit inside Up-Link MPA ALC circuit inside Control Panel (See Figure 5) Page 12
Figure 5 Control Panel Access Downlink Test Switch & LED Uplink Test Switch & LED DOWNLINK UPLINK 0 0 Downlink ALC LED Uplink ALC LED Page 13
DIAGNOSTICS GUIDE The BDA provides long term, care-free operation and requires no periodic maintenance. There are no user-serviceable components inside the BDA. This section covers possible problems that may be related to the installation or operating environment. a. Gain Reduction Possible causes: Bad RF cables and RF connections to antennas, Damaged antennas. b. Excessive Intermodulation or Spurious Possible causes: Amplifier oscillation caused by insufficient isolation.
