User's Manual Part 1

Table Of Contents

ADCP-75-187 • Preliminary Issue 1B • November 2005 • Section 2: DESCRIPTION

Page 2-2

1 INTRODUCTION

This section describes the basic components of a typical Digivance SCS system including the

Host Unit (HU), Remote Unit (RU), element management system, and accessories. The system

specifications are provided in a table at the end of this section.

2 HOST UNIT

Two versions of the HU are available. The rear access HU, shown in Figure 2-1, is used with

800/900 MHz SMR systems. The front access HU, also shown in Figure 2-1, is used with 800

and 1900 MHz systems. Connection points for the RF, optical, and alarm cables are provided on

the rear side of the rear access HU and on the front side of the front access HU. Both HU

versions provide the following basic functions:

• Provides a limited adjustable RF interface with the BTS.

• Provides a fiber optic interface with the RU.

• Digitizes the two forward path composite RF signals.

• Converts the two digitized forward path RF signals to a digital optical signal.

• Converts the digitized reverse path optical signal to two digitized RF signals.

• Converts the two digitized reverse path RF signals to two composite RF signals.

• Sends alarm information to an external alarm system through relay contact closures

• Provides an RS-232 interface for connecting the EMS computer.

• Provides a CAN interface for networking multiple HUs.

2.1 Primary Components

The HU consists of an electronic circuit board assembly and a fan assembly that are mounted

within a powder-paint coated sheet metal enclosure. The enclosure provides a mounting point

for the circuit board and fan assemblies and controls RF emissions. The only user-replaceable

component is the fan assembly. The HU is designed for use within a non-condensing indoor

environment such as inside a wiring closet or cabinet. The front access HU is also equipped

with a front cable management tray and vertical cable guides.

2.2 Mounting

The HU is intended for rack-mount applications. A pair of reversible mounting brackets is

provided that allow the HU to be mounted in either a 19-inch or 23-inch EIA or WECO

equipment rack. When the rear access HU is installed, the front panel of the HU is flush with the

front of the rack. When the front access HU is installed, the front panel of the HU is flush with

the front of the rack and the cable management tray extends 3.9 inches (99 mm) beyond the

front panel. Screws are provided for securing the HU to the equipment rack.