Earth-orbiting satellites can cover remote areas out of reach of wired networks or where construction of a cellular network is uneconomic. The Inmarsat satellite telephone system, originally developed in 1979 for safety of life at sea, is now also useful for areas out of reach of landline, conventional cellular, or marine VHF radio stations. In 1998 the Iridium satellite system was set up, and although the initial operating company went bankrupt due to high initial expenses, the service is available today.
[edit] Patents
- U.S. Patent 3,663,762: Cellular Mobile Communication System — Amos Edward Joel (Bell Labs), filed December 21, 1970, issued May 16, 1972
- U.S. Patent 3,906,166: Radio Telephone System (Dyna-Tac) — Martin Cooper et al. (Motorola), filed October 17, 1973, issued September 16, 1975
- U.S. Patent 4,144,411: Cellular Radiotelephone System for Different Cell Sizes — Richard H. Frenkiel (Bell Labs), filed September 22, 1976, issued March 13, 1979
- U.S. Patent 4,399,555: Cellular Mobile Radiotelephone System — Verne MacDonald, Philip Porter, Rae Young, (Bell Labs) filed April 28, 1980, issued August 16, 1983v
- U.S. Patent 5,129,098: Radio telephone using received signal strength in controlling transmission power — Andrew McGirr, Barry Cassidy (Novatel), filed September 24, 1990, issued July 7, 1992
- U.S. Patent 5,265,158: Construction of a stand alone portable telephone unit — Jouko Tattari (Nokia), filed May 11, 1992, issued November 23, 1993
- U.S. Patent 5,722,067: Security cellular telecommunications system — Douglas Fougnies et al. (Freedom Wireless), filed December 1994, issued February 24, 1998
- U.S. Patent 5,826,185: Cellular phone system wherein the air time use is predetermined — Andrew Wise et al. (Banana Communications), filed November 1994, issued October 20, 1998
- U.S. Patent 5,841,856: Hands-free telephone set — Yoshiyuki Ide (NEC), filed May 21, 1997, issued November 24, 1998
- U.S. Patent 7,324,480: Mobile communication apparatus and method including base station and mobile station having multi-antenna: Per-User Unitary Rate Control (PU2RC) — James S. Kim, Kwangbok Lee, Kiho Kim and Changsoon Park, filed July 10, 2003, issued January 29, 2008
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