Satellite Communications; Globalstar Simplex Satellite Network - Globalstar SmartOne Series User Manual

Satellite Communications

The SMARTONE communicates with both the GPS satellite Network and the
Globalstar Simplex Satellite Network. All GPS locations are pulled from
the GPS network and all transmissions are sent via the Globalstar
Simplex Satellite Network.
The SMARTONE has the unique ability to check its GPS Coordinates at a
programmable rate while it is inside of the Change of Location Area
without actually sending a message over the Globalstar Simplex Satellite
Network.
For a Location Message, the SMARTONE will wake up at a scheduled
interval or time of day and begins to acquire a GPS fix. Once it
receives its GPS fix, it will transmit the location to the Globalstar
Simplex Satellite Network.

Globalstar Simplex Satellite Network

The network consists of 40+ Low Earth Orbiting (LEO) satellites that are
constantly orbiting the earth and complete their orbits in less than 2
hours. Because of this, the SMARTONE will be in contact with at least
one of the satellites during each scheduled transmission. In LEO
communication networks the satellites are constantly changing their
positions in the sky relative to the transmitter on earth. This
minimized the shading effects seen in geostationary satellite systems
SmartOne Manual Rev 1.5 DOC# 9100-0268-01 p.9