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Reginald Fessenden experiments off the coast of Massachusetts with radio waves to determine the positions of ships.
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WWII radio navigation systems were developed.
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Soviet Union launched the first Sputnik. A team of U.S. scientists realized that if they knew their exact location on the globe, they could pinpoint where the satellite was along its orbit by measuring Doppler distortion.
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U.S. Navy's NAVigation SATellite System (NAVSAT) was developed. First operational satellite positioning system using a six satellite constellation for worldwide coverage.
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The Omega system provided worldwide electronic navigation coverage for the first time.
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Timation satellite proved the ability to place accurate clocks in space.
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The Department of Defense directed U.S. Navy and Air Force services to unify their systems. The basis for the new system was atomic clocks carried on satellites. The Air Force would operate the new system, which it called the Navstar Global Positioning Sy
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First Block-I GPS satellite launched.
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Soviet interceptor aircraft shot down the civilian airliner KAL007in restricted Soviet airspace. President Reagan announced that the GPS system would be made available for civilian aviation uses once it was completed.
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PSN-8 "Manpack" receiver, one of the first portable GPS units, available to soldiers in the field.
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Block-II GPS satellite launched.
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GPS was used extensively during Desert Storm and the Persian Gulf War.
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Complete 24-satellite GPS constellation in orbit.
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GPS is fully operational.
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Policy directive declaring GPS to be a dual-use (civilian-military) system and establishing an Interacgency GPS Executive Board to manage it as a national asset.
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Plans to upgrade GPS with two new civilian signals for enhanced user accuracy and reliability, particularly with respect to aviation safety.
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The first Block IIR-M is launched and the oldest satellite still in operation dates from Feb.1989.
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GPS is used everyday by everyone easily!
