"The main purpose of low-earth satellites is for rural areas, and Japan doesn't have many."

The phones can be used for wireless Internet connections, although the low-earth satellites usually only have enough bandwidth for slow-speed data transmission.

Orbcomm's low-earth satellites do not carry voice communications but instead are used to track rail cars, trucks and other vehicles and to monitor the status of pipelines.

These "low-earth satellites" would circle several hundred miles over the earth and would be much smaller and cheaper to launch than the big, traditional communications satellites that hover over one spot by matching the earth's rotation at an orbit 22,300 miles above the equator.

A U.S. Priority Obtaining radio frequencies for low-earth satellites was the top United States priority at this conference, which is held about every four years.

The 75-ton AEOS telescope points and tracks very accurately, yet is fast enough to track both low-Earth satellites and ballistic missiles.

Compared with geostationary satellites that remained at a fixed location some 22,300 miles above the equator, low-earth satellites use various orbital paths to buzz around the globe at altitudes of 500 to 600 miles.

Using low-earth orbiting satellites small antennas could be used to provide uplinks of as much as 100 Mbit/second and downlinks of up to 720 Mbit/second.

A low-earth satellite, which would be the size of a television set and would zip around the globe at an altitude of only 550 miles, could be built and launched for $1 million.