User's Manual

Andrew InCell™ Fiber Optic Distributed Antenna System Users Guide
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InCell™ Network Monitoring System
The InCell™ family is designed to minimize maintenance and monitoring costs. Provisions are
made for both local and remote monitoring of small and large systems. The InCell™ system
continuously monitors and reports status of the system hardware, by a combination of indicators
available at the central hub and at each remote antenna and alarms for remote monitoring that aid
in system fault detection and fault isolation down to a circuit board or cable.
The wideband, single mode fiber cable allows a low frequency RF test signal to be continuously
passed over the downlink and uplink signal paths with multiple RF wireless signals. In a dual
band system, the 67 MHz pilot test signal, the 800 MHz service, and the 1900 MHz service
signals simultaneously pass through the downlink and uplink paths.
Pilot Tone Generation
The CDU generates a continuous pilot tone for system level fault detection and isolation and
distributes the signal to each RAU port. This low frequency RF tone is combined with the
downlink RF signal and transmitted over the fiber optic cable to the RAU where it is received
and filtered from the downlink RF signal. In the RAU, the pilot tone is filtered, amplified and
combined with the RF uplink signal to be sent over the optical uplink path back to the CDU.
Within the RAU, the pilot tone is detected by a threshold detector to indicate the presence of the
pilot tone at a minimum signal level. The pilot threshold detector drives an LED on the RAU
that indicates that the downlink optical signal path to the RAU is connected.
The return path pilot tone from the RAU is also filtered, amplified and detected. The detected
pilot signal is passed to a threshold detector to indicate the tone presence at a minimum signal
level. The pilot threshold detector in turn drives an LED at each port of the CDU indicating that
both the downlink to the RAU and the uplink back to the CDU are connected and that power is
properly functioning at the RAU.
RAU Indicators
The Power indicator on the RAU shows that DC power from the composite cable is present at
the RAU. If the indicator is green, DC power is present in the RAU.
The LINK indicator on the RAU shows that the pilot tone from the CDU is present over the
downlink. When the LINK indicator is off on the RAU, the downlink optical path between the
CDU and the RAU is installed correctly and DC power is present in the RAU. If the LINK
indicator is red, there may be a problem with the downlink optical path between the CDU and
RAU or a problem with the RAU power. The RAU indicators allow system installers and
maintainers to easily determine the RAU functional status, the power supply status, and the
downlink optical path status.
CDU Front Panel Indicators
The Power indicator for each port of the CDU indicates that the DC power is present at that port.
If the CDU Power indicator is green, power is good at that CDU port, also indicating that the
internal AC power supply is good. If the Power indicator for one CDU port is off, there is