Install Basestation Unit - Cisco BWX 8305 Installation And Commissioning Manual

Chapter 6 Installation

6.4.4 Install Basestation Unit

Ensure that the power to the BS unit is OFF before installing the unit in a rack or cabinet.
Warning
Place the BS unit into a standard 19" or 23" rack or outdoor enclosure. Once installed, go ahead to the
next section of this Guide and install the BWX 8303 Basestation Timing System. After the BWX 8303
Basestation Timing System is installed and its cables swept, you will return to the remaining BS
installation. Please note that the BS does not have an air filter option like its predecessor BS.
The RF ports on the BS output a +24 VDC current, which is carried to the BWX 8305 Basestation
Caution
Antenna through RF cables. This DC current may damage test equipment connected directly to the RF
ports or to the end of the RF cables at the BWX 8305 Basestation Antenna. When connecting test
equipment to the output of an RF port, an external DC block may be required. Most signal generators
and spectrum analyzers cannot handle DC voltage on the I/O ports. Please, read the caution stickers on
the equipment and provide a DC block if the equipment cannot handle over zero (0) VDC.
6.5 Connect BWX 8303 Basestation Timing System
Reference: BWX 8303 Basestation Timing System Operation & Maintenance Manual
The BWX 8303 Basestation Timing System is required for WiMAX Basestations.
Note
6.5.1 Overview
The BWX 8303 Basestation Timing System is a new feature with BWX 8305 Basestations supporting
WiMAX certification requirements for high-resolution timing. The ports on the BWX 8303 Basestation
Timing System provide 1 pulse per second (1 PPS) and 10 MHz source.
For the BS to be WiMAX certified, the BWX 8303 Basestation Timing System provides very precise
frequency timing to the BS. The BWX 8303 Basestation Timing System receives the timing signal from
the GPS antenna and outputs a 1 pulse per second (PPS) signal, along with an extremely accurate (< 0.02
ppm) 10 MHz reference signal that is locked to the GPS timing. This timing reference is then utilized by
the BS to derive the carrier frequency (2500 MHz, for example) and synchronize its TDD framing to
other Basestations. This Synchronized signaling is important for avoiding interference from co-located
or adjacent BSs. Also, when using the Cisco BWX WiMAX Diagnostics tool, having GPS timing also
permits the system to determine a user's location via triangulation.
One BWX 8303 Basestation Timing System can provide the required reference signals for up to three
BSs; thus, a single BWX 8303 Basestation Timing System is required for a tri-sectored site.
The BWX 8303 Basestation Timing System unit described here handles the more precise frequency
Note
referencing required for WiMAX mobility, and has its own GPS antenna port. Therefore, the GPS port
from the BS faceplate is not needed for a GPS antenna.
OL-16336-02
Connect BWX 8303 Basestation Timing System
BWX 2305 Basestation Installation and Commissioning Guide
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