Sutron Corporation X-Link Operations & Maintenance Manual, Rev 1.63 5/24/2016 pg. 56
5.4.
Iridium Telemetry
IRIDIUMLink uses the Iridium satellite constellation to deliver sensor data.
Iridium satellite coverage is available everywhere. The diagram below shows
how the signal travels through the Iridium Gateway to an email address, etc.
5.4.1.
Iridium Antenna Placement
IRIDIUM Link's antenna must be placed where it has a clear view of the sky.
Iridium satellites are not geostationary. This means that coverage of a certain
area may vary from one minute to the next. The station must have a strong
signal for 10 to 20 minutes.
The antenna-aiming feature can aid in correct station setup. It will show the
current signal strength. Signal strength ranges from 0 (no signal) to 5 (excellent
signal).
A signal strength of 4 or higher indicates a strong signal.
IRIDIUMLink needs to consistently report a strong signal for 10 to 20 minutes
to indicate good antenna placement.
If signal strength is varying, the antenna's view of the sky is obstructed.
In theory, any signal strength above 0 means that a transmission can be
made. However, to ensure reliable and consistent data transmissions,
reposition the antenna to get better signal.
A signal strength of 0 indicates that there is no signal at all; IRIDIUMLink will
not be able to make any transmissions.