The Globalstar space segment is based on a low earth orbiting satellite constellation.
This constellation consists of 48 LEO (Low Earth Orbiting) satellites, with an additional
four satellites in orbit as spares.
Owing to the low earth orbit of the Globalstar system satellites, signal delay and
distortion is minimized. The Globalstar satellite system has been designed such that
it does not require complicated and large user terminals. This allows the user to
enjoy a portable user terminal not much larger than a cellular phone.
The Globalstar satellite is simple; Each consists of an antenna, a trapezoidal body,
two solar arrays and a magnetometer, and operates at an altitude of 1,414km (876 miles).
The satellites are placed in eight orbital planes of six satellites each, inclined at
52 degrees to provide service on Earth from 70 degrees North latitude to 70 degrees
South latitude all around the world.
| Number of satellites in the constellation |
48 |
| Number of orbits |
8 |
| Orbit elevation km |
1410 |
| Inclination |
52° |
| Number of satellites per orbital plane |
6 |
| Number of satellites simultaneously covering the territory of Russia - no less than |
4 |
| Weight of satellite kg |
< 450 |
| Life span |
10 years |
The design of Globalstar's orbital planes keeps two to four satellites overhead at all
times from any point of the earth's surface, other than the poles.
CDMA (Code Division Multiple Access) technology, which permits dynamic selection of
strongest signal available from all satellites in view, is a technique we refer to as
path diversity, resulting in superior call clarity and a low incidence of dropped calls:
as the satellites and the user change positions, satellites are added and dropped
seamlessly from the call.
The Globalstar satellite constellation was launched using the Delta-II rocket boosters
(USA) and the Souyz-Ikar rocket boosters (Russia). Launches were carried out from the
Kennedy Space Center in Florida, and the Baikonour Cosmodrome in Kazakhstan.
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