AN-80i
Installation Guidelines
70-00073-01-08-b
Proprietary Redline Communications © 2011
Page
15
of 58
May 27, 2011
The outdoor unit can be used with a selection of available external antennas. When
equipped with a narrow beam antenna, the AN-80i supports long-range operations of
over 50 miles (80 km) in clear line of sight (LOS) conditions. The AN-80i outdoor unit is
housed in a weatherproof aluminum alloy case. An indoor PoE power adapter provides
operational power for the AN-80i and connection to the Ethernet network.
One AN-80i is configured as PTP Master or PMP Sector Controller and controls the
wireless link. This function is transparent to all Ethernet operations. The Master/sector
controller uses a scheduled request/grant mechanism to arbitrate bandwidth requests
from the remote unit (PTP Slave / PMP subscriber) to provide non contention-based
traffic with predictable transmission characteristics.
2.2
RF Interference
Frequency planning is an essential component of installation and it is very important to
test for RF interference at every installation site. The AN-80i will not achieve full
operational capability if there is excessive interference on the same or adjacent RF
channels.
RF interference may be caused by another wireless system operating on the same or
adjacent RF channels. A simple test may be performed using the AN-80i built-in
spectrum sweep feature to determine if a selected RF channel is generally free from
interference. This procedure is described in the configuration section of this manual.
2.3
Path Profile
The site survey should identify the optimum location for mounting the AN-80i. For
maximum performance, there should be a direct line of sight to the receiving wireless
system.
The antenna should be positioned to provide maximum clearance within the first Fresnel
zone of the direct path (as high as possible, on either a tall building or tower). A clear
line-of-sight (LOS) path requires clearance above natural and man-made objects by at
least 60% of the First Fresnel zone.
Figure 3: Site Survey - Fresnel Zone Radius
The AN-80i will also function under optical line-of-sight (OLOS) conditions; where a clear
straight line path exists between the two end points, but the first Fresnel zone is not
clear. If the optical path is completely blocked, it may still be possible to establish a non
line-of-sight (NLOS) path using reflections and diffraction. A satisfactory multipath RF
signal may be obtained by directing both AN-80i antennas towards a reflective structure
that is within sight of both units.
