User Manual

Table Of Contents

SPA9329-35 Installation & Service Manual

Section 4 Principles of Operation

4-1 Introduction

This section contains a functional description of the SPA9329-35 power booster amplifier.

4-2 RF Input Signal

The maximum input power should not exceed the limits specified in table 1-1.

4-3 RF Output Load

The load impedance should be as good as possible (1.5:1 or better) in the working band for good

power transfer to the load.

4-4 Amplifier Functional Description

The SPA9329-35 power booster amplifier, shown in figure 4-1, operates in the 1930 MHz to

1990 MHz range. The operating band is determined by the operating frequency selection(s) of

the base station (refer to table 1-2). The amplifier module consists of a single carrier amplifier pal-

let with the necessary combining and filtering to produce up to 100 watts (50 dBm) of output

power with a maximum gain of 23 dB. The amplifier employs a class AB amplifier for maximum

efficiency. The amplifier operates on +27 Vdc.

The amplifier is compliant to the requirements of FCC Part 24 with respect to spurious emissions

(see table 1-2). All gain variations, for example those due to temperature, are reduced to the pas-

sive reference variations.

RF In

RF Out

Reverse

Detector

Comparator

and Alarm

Circuit

SPA9329-35

+27 VDC

TMP

Pre-Amp

Main

Amplifier

Figure 4-1 SPA9329-35 Booster Amplifier Block Diagram

4-5 Amplifier Module Cooling

Each amplifier module is cooled using a rear-mounted fan circulating air flow across the amplifier

heat sinks, the air then exits out the front of the module. This provides sufficient cooling to main-

tain the amplifier within the specified operating temperature range.

4-1 October 2002