User Manual

ADCP-75-159 • Issue 1 • August 2003 • Section 2: Description
Page 2-3
© 2003, ADC Telecommunications, Inc.
1 INTRODUCTION
This section describes the basic components of the Digivance SMR 20 Watt system including
the Host Unit (HU), the Remote Unit (RU), and the Digivance Element Management System
(EMS). Also described are various accessory items including the Interface Panels, Wavelength
Division Multiplexer (WDM) system, and Coarse Wavelength Division Multiplexer (CWDM)
system. The RU is an assembly that consists of a cabinet (for outdoor applications) or mounting
shelf (for indoor applications), a Spectrum Transport Module (STM), and a Linear Power
Amplifier (LPA) module. For clarity, the various components that comprise the RU are
described separately.
2 HOST UNIT
The HU, shown in Figure 2-1, serves as the EBTS servicing unit for the Digivance system. The
HU provides the following basic functions:
• Provides a gain adjustable RF interface with the EBTS.
• Provides a fiber optic interface with the RU.
• Digitizes the forward path composite RF signal.
• Converts the digitized forward path RF signal to a digital optical signal.
• Converts the digitized reverse path optical signal to a digitized RF signal.
• Converts the digitized reverse path RF signal to a composite RF signal.
• Signals 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 RF connectors, optical connectors,
alarm output connectors, DC power terminal strip, and grounding lug are mounted on the HU
rear side. The On/Off power switch, LED indicators, service interface connector, and Controler
Area Network connectors are mounted on the HU front panel.
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 installed, the front panel of the HU is flush with the front of the rack.
Fasteners are provided for securing the HU to the equipment rack.