5. Links

Introduction

The Global Positioning System (GPS) satellite constellation was originally implemented to provide navigation and tracking information to the United States military branches throughout the world. Today, the system can provide accurate, continuous, worldwide, three-dimensional position and velocity information to any user with the appropriate receiving equipment. GPS navigation tools can be found in amateur as well as commercial aircraft; cargo boats; luxury cars and even handheld unit used by hikers

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There are three main segments to GPS: space segment, operation control segment, and user equipment segment.  The space segment includes the satellite constellation of 24 geo-synchronous satellites. (See Fig.1)  The operation control segment is comprised of a Master Control station and several ground monitoring stations that track, maintain and update the satellite clock corrections as well as other flight parameters.  The user, receiving, segment executes navigation, timing or other procedures as is required for the function the user wishes to perform