Airspan AS4000, Installation Manual

Page: 84 / 193

Printed Documentation
80
AS4020 CT Shelf Installation and Cabling
Shelf Connections
AS4020 comprises of a single 65mm (approximately 1.5u) high shelf, which can be fitted in an
ETSI rack, 19" rack or 21" rack. AS4020 is flexible in its deployment, although is must remain
within a couple of meters of the radio sub-system. Initially the AS4020 CT shelf is fitted within
the AS4000 CT rack with the Radio sub-system, and optionally alongside up to two AS4000
CT shelves. Alternatively a half-height AS4000 CT rack can fit four AS4020 shelves and a
radio sub-system.
All connections to the AS4020 shelf are through the front of the unit, except DC power, which
is fed from the RF combiner shelf to the rear of the unit. the illustration below shows a the
interfaces available on the front of the AS4020 CT shelf. All connections are made to the front
panel with the exception of the power connection at the left hand side of the shelf.
All cables should enter via the cable tray above the shelf. Cable entry to the main panel is via
the left hand opening and via the right hand opening to the option panel as this avoids the
possibility of cables obscuring the menu.
The AS4020 CT shelf is cooled using fans that are hot-pluggable in the event of failure. An
AS4020 CT shelf can only be installed in a weather-protected location.
The AS4020 CT shelf provides a terminal connection for initial configuration of the Ethernet
ports, a method for commissioning the system, and menus for basic systems diagnostics. In
addition to the terminal interface, AS4020 contains an LCD screen to provide alarm details
and limited status information.
Full configuration of AS4020 is via the management system, which can be a local Ethernet
connection, or via the network Ethernet interface.
The AS4020 CT shelf provides the switching functionality of the system, as well as managing
radio access on both the uplink and downlink. The shelf is also responsible for the radio
interface architecture, namely BDM, dynamic modulation, and RTS/CTS signalling.
When adding shelves to an existing AS4000 system use the following diagrams to determine
the points to connect the radio port and combiner monitor connections.
o
Adding one AS4020 shelf
o
Adding two AS4020 shelves
o
Adding three AS4020 shelves
o
Adding four AS4020 shelves
o
Adding Two AS4020 Shelves to an existing Two AS4000 shelf rack
Installing the Voice Option Board
Units are shipped with the option board installed if specified, but options boards may be
added to existing shelves.