User's Manual

Andrew InCell™ Fiber Optic Distributed Antenna System Users Guide
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problem with that CDU port interface. If the Power indicators for all CDU ports are off, the AC
power supply may be bad, AC power may be switched off or there may be another problem with
the AC power.
The LINK indicator at each CDU port shows that the CDU generated pilot tone was sent over
the downlink from the CDU to the RAU then received and transmitted over the uplink path from
the RAU back to the CDU. When the CDU LINK indicator is off, the downlink and uplink
optical paths are installed correctly and DC power is present in the RAU. If the LINK indicator
is red, there may be a problem with the fiber optic signals between the CDU and RAU; a
problem with the RAU power; or a problem with the RAU itself. The CDU indicators allow
system installers and maintainers to easily determine each RAU functional status, power
distribution to each RAU, and the correct connection of the fiber optic cables.
Alarm Functions
The CDU has two alarm outputs on the rear panel to indicate the overall health of the power
supply and the uplink and downlink to each remote antenna units. The link alarm output is a
summary alarm of all of system uplinks and downlinks and remote antenna power. The alarm
outputs are through a DB-9 connector located on the CDU chassis rear panel.
Remote Monitoring Functions
As an option that will be available in February 2001, InCell™ Systems will support remote
system health monitoring using standard protocols that will allow customers to monitor full
system status. This feature uses an embedded processor (see Error! Reference source not
found.) to monitor and report system health for the CDU and all RAUs, including power
supplies, uplink and downlink paths and cables.
With this option, the InCell™ System hardware can be remotely monitored in three ways:
v Locally using a RS-232 connection to a terminal or PC (see Figure 13)
v Remotely using an SNMP Agent chassis connected to a telephone, LAN/WAN or other
communications medium
v Remotely using dry-contact terminals connected to a third party SCADA
In the first method, the RS-232C interface option does not require a separate chassis. An RS-485
bus daisy chains the system status and alarms together as illustrated in Figure 13 and Figure 14.
Communications between CDU’s is accomplished over an RS-485 link, and the user can connect
to the master bus using a standard computer or RS-232C terminal.
In the second method, a separate 1U chassis is required to act as the SNMP agent. The SNMP
agent allows a network management system to monitor InCell™ device(s) by telephone or
network connection using industry standard interfaces. The SNMP agent performs network
management operations such as setting configuration parameters, alarm notification and current
operation statistics. A database of the InCell™ network management information, called the
management information base (MIB), is maintained by the Agent.