User's Manual

044-05454 Rev A 1
Chapter 1
Product Description
Introduction
This manual contains information and procedures for the installation, operation, and maintenance of the G3L-
850-180 Multi-Carrier Power Amplifier (MCPA).
Scope of Manual
This manual is intended for use by service technicians familiar with similar types of equipment. It contains
service information required for the equipment described and is current as of the printing date. Changes which
occur after the printing date may be incorporated by a complete manual revision or alternatively as additions.
The manual is organized into the following chapters:
❑ Ch
apter 1 - Product Description
❑ Ch
apter 2 - Controls and Indicators
❑ Ch
apter 3 - Installation
❑ Ch
apter 4 - Maintenance
❑ Ch
apter 5 - Specifications
Product Description
The MCPA shown in Figure 1-1 MCPA Front and Rear Views is a linear, feed-forward multi-carrier power
amplifier that operates in a 25MHz frequency band from 869 MHz to 894 MHz with an instantaneous bandwidth
o
f 25 MHz. The instantaneous bandwidth is the maximum frequency band in which any two or more signals can
occupy. The instantaneous bandwidth of the MCPA is set automatically.
The MCPA is modular in design and ideally suited for use in GSM, UMTS, EDGE, CDMA, and W-CDMA base
s
tations. The MCPA provides a gain of 63 dB to provide a 210 watt output at 27 VDC and 25 °C with seven GSM
+ one EDGE signal; 150 watts with 7.5 dB PAR signal of any combination of EDGE, GSM, W-CDMA, with a
maximum of four EDGE, a maximum of eight GSM/EDGE and a maximum of two W-CDMA signals; and 130
watts with a maximum of four W-CDMA or eight CDMA signals. Refer to Figure 1-2 MCPA Functional Block
Diagram for the MCPA functional block diagram. Refer to Chapter 5 for the MCPA specifications.
Functional Description
The MCPA is a self-contained module typically operated in parallel with other identical MCPAs as part of a
subrack assembly.
The MCPA consists of the following major functions:
❑ P
reamplifier
❑ M
ain and error amplifiers
❑ F
eed-forward loop control circuits
❑ P
ilot tone generator
❑ Co
ntroller