RST978 INSTALLATION & USER MANUAL
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Assuring Quality of Iridium Service
Iridium is committed to providing users around the world consistent, reliable, quality
voice and data access all day every day. The Iridium satellite system is monitored for
call performance from numerous locations 24 hours a day, 7 days a week in order to
achieve this.
Iridium continually strives to provide high quality voice and data communication links
for its subscribers. However, there are conditions that can compromise the quality of
the service you may receive.
There are three common factors regarding the user's environment that can lead to
degraded service quality. Obstructions and Interference
Obstructions.
For best performance, the user’s antenna must be able to “see” the entire sky from
approximately 8 degrees above the horizon. Nearby tall buildings or similar
structures, heavily leafed trees, mountains, etc. can degrade performance as they
block the signal between the equipment’s antenna and the satellites. Having a
completely open view of the sky plays a very important role in maximizing
performance, as the Iridium satellites cross the sky from horizon to horizon during a
call connection.
A good rule of thumb is that all surrounding obstructions should be lower than the top
of a fist, which is extended at arms length, and the bottom of the fist placed on the
horizon. Note that Iridium performance is immune from natural environments such as
clouds, fog, rain, snow, wind and smoke.
RF Interference.
All wireless devices, including satellite telephones, are susceptible to RF (radio
frequency) interference from other electronic devices. This problem is especially
evident when numerous antennas and broadcasting devices are located within close
proximity to each other.
A good example would be onboard a ship. It is important that certain considerations
be taken into account for best performance when an Iridium system is installed.
Causes of RF Interference
Some subscribers have contacted Iridium regarding the loss of signal quality when
they operate their equipment near active INMARSAT terminals. The power with which
INMARSAT units transmit can overpower the Iridium unit’s ability to properly maintain
a quality connection with the Iridium satellite constellation. INMARSAT terminals are
often found in the same locations as Iridium subscribers, such as harbours, airports
and especially onboard ships.