Classroom Companion: Business

 IP in the Sky
The feasibility of offering satellite services 
directly to the users of maritime and aero-
nautical applications using geostation-
ary satellites was confirmed by several 
studies in the late 1960s. This led to the 
establishment of the Inmarsat organiza-
tion in 1981, primarily offering satellite 
communications to ships and later also 
to aircraft. These systems are using geo-
stationary satellites at a height of 36,000 
kilometers above the Equator. These sys-
tems require big and expensive satellites 
and are not feasible for cheap broadband 
communications with handheld terminals. 
For this purpose, several systems using 
lightweight satellites in low Earth orbits 
(LEO) (less than 2000 kilometers above 
the Earth) have been put into operation 
or are planned. For more details, see the 
homepages for the projects listed below.
Iridium is a system consisting of 66 
satellites in polar orbits at a height of 780 
kilometers above the Earth. The origi-
nal concept included 77 satellites, and 
the system was named after the element 
with atomic number 77 in the periodic 
table, iridium, since the system looked 
like an atomic nucleus surrounded by 77 
electrons. The Iridium system was down-
scaled to 66 satellites. Element number 
66 is dysprosium, a less appealing name, 
so that the original name was kept. 
Iridium commenced operation in 1998 
after severe initial financial problems, 
offering telephone services to handheld 
terminals. Since 2018, the system also 
offers data communications with data 
rates from 128 kilobits per second to 8 
megabits per second to fixed and mobile 
terminals.
Globalstar is an American company 
offering telephone services and low-speed 
data communications (9.6 kilobits per 
second) to portable telephone and data 
terminals. The system consists of 24 sat-
ellites at a height of 1400 kilometers in 
orbits with an inclination of 52 degrees.
ORBCOMM offers Internet of 
Things (IoT) connections using both 
cellular and satellite networks. The com-
pany has more than two million sub-
scribers in more than 130 countries. The 
satellite network consists of 31 light-
weight satellites in various low Earth 
orbits offering low-speed data commu-
nications to IoT devices. The company 
has offered satellite communications 
since 1990.
Teledesic was founded in 1990 to build 
a global satellite network for broadband 
Internet communications. The system 
should consist of 840 satellites in low Earth 
orbits. It was soon downscaled to 288 sat-
ellites. The project was abandoned in 2002