American Mobile adds security to federal satellite telephone service

American Mobile Satellite Corp. of Reston, Va., in June began selling Secure Telephone
Unit III service with its satellite communications. The service can secure links over
wireless and public switched telephone networks.

The STU III dedicated telephone is the federal standard for secure telephone
communications by military, law enforcement and intelligence agencies. It encrypts analog
voice signals for transmission over ordinary telephone lines.

An STU III Interface Unit from American Mobile converts the encrypted analog signal to
a digital signal stream for transmission over the satellite network, said Steve Yocum,
product manager for American Mobile’s Skycell service.

The interface unit connects to the serial port of an approved mobile satellite
terminal, used for digital satellite networks. The STU III telephone plugs into the
interface’s RJ-11 port.

The Skycell service operates via a single satellite, owned by American Mobile, to
provide remote telephone service throughout North America and parts of the Caribbean and
Latin America, Yocum said.

In addition to direct dial voice and STU III services, Skycell provides
circuit-switched data communications and faxing.

The STU interface units are sold separately by American Mobile and authorized dealers.
They start at $1,700 plus airtime, which costs $0.99 to $1.49 per minute, depending on the
equipment chosen. Federal Skycell users include the Coast Guard and the Defense, Justice
and Interior departments.

Contact American Mobile at 800-405-6543.  

About the Author

William Jackson is a Maryland-based freelance writer.


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