Chapter 2 - System Installation; Introduction; Environmental And Line Of Sight Concerns; Link Availability - Harris RF-7800W-OU470 Installation & Operation Manual

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INTRODUCTION

Consider the following before installing a RF-7800W High Capacity Line of Sight (HCLOS) Radio system:
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Environmental and Line of Sight concerns

•

Link Availability

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System Configuration

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Co-location
2.1.1 Environmental and Line of Sight Concerns
The RF-7800W is a microwave radio, which demands better Line of Sight (LOS) conditions than other radios that
operate with a lower frequency. Optical Line of Sight (OLOS) alone may not be adequate enough to maintain a
healthy link between radios. The radio operates at a lower power than other Harris radios, but high-gain antennas
give it the ability to link over many tens of kilometers in some situations. At these distances, weather and the
curvature of the Earth can become major factors affecting link quality. A thorough propagation study and analysis
using industry standard ITU recommended guidelines should be performed before deploying radios in an unknown
or unfamiliar location.
2.1.2 Link Availability
Harris provides a free tool to users that wish to perform a simple evaluation of a single RF-7800W radio link under
ideal environmental and terrain conditions. The Link Budget Tool (included with CD-ROM) provides a rudimentary
calculation of annual Link Availability (Uptime) and can help users choose the right antenna for their specific
installation.
2.1.3 System Configuration
There are two configuration types:
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Simple Point to Point (SPTP) - Two RF-7800W radios are used, one as a Sector Controller (SC) and one as
a Subscriber Station (SS).
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Simple Point to Multipoint (SPMP) - Two or more RF-7800W radios are used, one as a Sector Controller
(SC) and the rest as Subscriber Stations (SS).
Some RF-7800W link configuration and statistics are split into downlink and uplink. The downlink direction always
refers to data or signals transmitted away from the SC toward an SS. The uplink direction always refers to data or
signals transmitted by the SS toward the SC.
CHAPTER 2
SYSTEM INSTALLATION
Previous generations of the RF-7800W radio used the terms
Master/Slave instead of SC/SS.
NOTE
RF-7800W
SYSTEM INSTALLATION
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