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or GPS is better known as "a satellite based radionavigational system developed and operated by the U.S. Department of Defense (DOD). permits land, sea, and airborne users to determine their three-dimensional position, velocity, and time twenty-four hours a day ....

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.... with no direct charge." (Tycho) The SPS is provided on the L1 frequency, which then will code a navigational message. The SPS accuracy is 100-meter horizontal, 156-meter vertical, and 340 nanoseconds time, and in total the SPS is ninety-five percent accurate. (Utexas) The Department of Defense also degrades this service so those consumers can use this service. Secondly, the Precise Positioning Service or PPS " is a highly accurate military positioning, velocity and timing service which is available on a continuous, worldwide basis to users authorized by the U.S. PPS is the data transmitted on GPS L2 frequency. Precise Positioning Service was ....