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Showing papers on "GPS/INS published in 1986"


26 Jun 1986
TL;DR: This paper analyzes two receiver-based methods for assuring the integrity of Global Positioning System (GPS) signals-in-space, called the range comparison method and the position comparison method.
Abstract: Integrity is the ability of a system to let its users know whether the system is operating out of its specified performance limits This paper analyzes two receiver-based methods for assuring the integrity of Global Positioning System (GPS) signals-in-space These methods are called the range comparison method and the position comparison method Equations relating unknown satellite range errors to the quantity measured in each method are analyzed The equations reveal important characteristics of the methods, including their mathematical equivalence The performance of the two methods is derived in terms of satellite range errors Numerical results are then obtained for the performance of the methods, alone and in combination with monitoring of the receiver clock bias estimate

161 citations


Journal ArticleDOI
TL;DR: A joint research project among Boeing, Rockwell-Collins, and Northrop has been completed in which a GPS receiver was integrated with a low-cost strap-down inertial navigation system and a flight computer, resulting in a system that combines the accuracy of GPS with the jamming immunity and autonomy of inertial Navigation.
Abstract: The Global Positioning System is an extremely accurate satellite-based navigation system which, after its completion in 1989, will provide users worldwide, 24 hour. all weather coverage. A joint research project among Boeing, Rockwell-Collins, and Northrop has been completed in which a GPS receiver was integrated with a low-cost strap-down inertial navigation system and a flight computer. A Kalman filter in the latter allows in-fight alignment and calibration of the INS. In addition, feedback from the INS to the GPS receiver improves the system's ability to reacquire satellite signals after outages. The resulting system combines the accuracy of GPS with the jamming immunity and autonomy of inertial navigation. System tests were conducted in which a Boeing owned T-33 jet aircraft was flown through known test pattern to align and calibrate the INS. Earlier tests, including tests against an airborne jammer, were conducted in a modified passenger bus.

22 citations