User's Manual

Exalt Communications, Inc.
Exalt i-Series Installation and Management Guide
5000001 108
2007-04-15
by the radio indicates the level of interference seen by the radio. It is possible that
interference levels below that which can be measured still have an impact on the radio
system – especially if the radio system has low fade margin or is using a high order
modulation.
The EX-2.4i and EX-5i families provide considerable flexibility to tune to different
frequencies across the bands within which they operate. This is the easiest method to use
to try to avoid existing interference. In addition, the occupied bandwidth of the radio can
be reduced. This, along with re-tuning, can be very effective, however throughput is
reduced.
Repositioning the antenna and/or changing polarization, or upgrading the antenna to a
higher gain, and/or using a high-performance antenna, are all secondary means that can
be used. It may be necessary to perform combinations of both radio changes (retuning,
occupied bandwidth reduction) and antenna system changes (position, polarization,
upgrade).
The EX-4.9i radio operates under licensed regulations. If interference is suspected, the
local frequency coordination organization, or other users of the spectrum should be
consulted before re-tuning the radio to a different frequency channel.
Path Obstruction
A path obstruction is defined as an object, such as a building or tree, impeding the proper
path of the radio system. If the system design was proper at the time of installation and
issues arise at a later date, an updated path profile and survey may be necessary to
identify changes in path clearance.
Misaligned Antenna
At the time of initial installation, it is critical that the antennas at each end are properly
aligned and that the designed RSL is achieved. However, antennas may become
misaligned due to high winds, changes in the guy-wiring systems keeping the antenna
mast stable, or loosening of the antenna mounting hardware. A reduction in the RSL of
the link is symptomatic of this condition, but this condition is not the only condition that
results in a reduction of RSL. However, if conditions occur where the antenna alignment
may be suspected, the mechanics must be inspected and the antennas realigned.
Faulty Antenna
A faulty antenna is rare, but is still a possibility. In some cases, the mechanics of the
antenna feed can get moisture inside, or a bad or weak connection in the pin and
connector structure of the antenna may occur. A VSWR measurement of the antenna
connection can be made to verify this condition.