User Manual

AS4000 Wireless Local Loop
System Overview
GSI 002
605-0000-430
Issue 1.2 Date 7/4/99
Page 7 of 8
3.2 Power Requirements
Each Rack requires two DC power supplies. The supply can range from -22 Volt to -60
Volt DC. The input current for a fully loaded rack is 28 Amps at 22 Volt reducing to 8.5
Amps at 60 Volt.
3.3 CT Equipment Rack Shelves:
Modem Shelves
Each Modem Shelf terminates one RF Channel, supporting up to 15 radio links, provides a
CAS or DASS2 network interface with the Local Exchange and a V.24 (RS232) Network
Management interface to the Sitespan. Up to four Modem Shelves can be equipped to
support 60 radio links and four network management interfaces within a single rack.
Each Modem Shelf has:
• a Tributary Unit (TU) Card, which provides the interface between the Local Exchange
equipment and AS4000 Radio System for traffic and signalling information.
• up to eight Modem Cards (each card supports 2 radio links) These cards provide the
core SS-CDMA modem functionality interfacing traffic channels between the TU Card
and the Analogue Card and management signals to the Shelf Controller Card.
• an Analogue Card, which converts the coded signals from the Modem Cards to a base
band signal (for the RF Card in the RF Combiner Shelf) and supplies the TU Card with
the recovered 2 MHz clock signal.
• a Shelf Controller Card, which provides the management interface between the AS4000/
Sitespan /EM and its supported Central Terminals. It also holds the configuration details
in NVRAM.
• an LED/Alarm Panel, which provides LEDs that reflect the overall status of the system
and an key switch used to acknowledge that a fault condition is receiving attention.
A Modem Shelf can be equipped with up to eight Modem Cards, each card supporting two
radio links, (i.e. 16 radio links per shelf of 15 customers). This arrangement results in one
spare modem per shelf. The spare modem is held in reserve and, if necessary, can be
reconfigured to automatically replace a modem that has a fault. (see Figure 17).