G Way Solutions PS725W90 Users Manual

INSTALLATION

AND

OPERATING MANUAL

BDA-PS7-2/25W-90-AB

BI-DIRECTIONAL AMPLIFIER

TABLE OF CONTENTS

PARAGRAPH PAGE NO

BDA OVERVIEW 3
BDA BLOCK DIAGRAM DESCRIPTION 3
BDA BLOCK DIAGRAM DRAWING (Figure 1) 4
ELECTRICAL SPECIFICATIONS 5
MECHANICAL SPECIFICATIONS 6
ENVIRONMENTAL CONDITIONS 6
BDA CONNECTIONS 6
MECHANICAL OUTLINE DRAWING (Figure 2 & 2a) 7
BDA INSTALLATION 8
BDA OPERATION 9
UPLINK MECHANICAL OUTLINE- ADJUSTMENT (Figure 3) 10
RF EXPOSURE WARNING 11
DIAGNOSTICS GUIDE 11

Page 2

BDA OVERVIEW:

The BDA assembly enhances 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.

BDA BLOCK DIAGRAM DESCRIPTION

:

Refer to figure 1 for the following discussion.
The BDA Downlink path receives RF signals from the base station and amplifies a nd

transmits them to the subscriber. The BDA Uplink path receives RF signals from the
subscriber and amplifies and transmits them to the base station. The Uplink and
Downlink occupy two distinct frequency bands. For example, the PS7 frequency
bands are as follows: 793-805 MHz for the Uplink and 763-775 MHz for the Downlink.
Two diplexers isolate the paths and route each signal to the proper amplifying
channel.

An Automatic Level Control (ALC) allows for output power limiting. A variable step
attenuator gives 0 – 30 dB of attenuation in 2 dB steps. The use of these controls is
covered in the “OPERATION” section, later in this document.

Page 3

Figure 1

1. 2. 3.

5

. 7.

4.

6.

BDA BLOCK DIAGRAM

BDA-PS7-2/25W-90-AB

1

. Uplink Diplexer - has low passband insertion loss and high selectivity.

2

. Downlink Pre-amp - is a low noise amplifier that drives the Downlink HPA and offers

43dB Gain.

3

. Downlink PA – is a high power amplifier with an ALC circuit which offers 46dB Gain.

4

. Uplink MPA – is a medium power amplifier with an ALC circuit which offers 46dB

Gain.

5 gain syste

. Optional Filters – for additional Isolation in 90 dB ms.

6. w noise amplifier that drives the Uplink MPA and offers 43dB

Uplink Pre-amp - is a lo
Gain.

. Downlink Tx filter is enhanced for High Power applications, preventing arching when

7

the power amplifier approaches the 1dB compression point.

Page 4