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GPS Integrity Architecture Opportunities



Marc A. Weiss, Calvin Miles, Karl J. Kovach, John Dobyne, Karen Van Dyke


The Global Positioning System (GPS) integrity architecture forms the basis for several GPS integrity augmentation systems, most notably, the Wide Area Augmentation System (WAAS), Receiver-based Autonomous Integrity Monitoring (RAIM) and its proposed extension the Advanced RAIM (ARAIM). This paper surveys several opportunities to increase the integrity of GPS. These opportunities are accompanied by the motivation to use the increased integrity to increase the performance of ARAIM and WAAS. Some of these opportunities already exist today, like taking credit for the GPS a priori failure rates determined by Integrity Failure Modes and Effects Analysis (IFMEA). Some are part of the current GPS program evolution, while others could be incorporated into the later stages of the GPS III satellites and the Next Generation Operational Control System (OCX) programs. The current level of GPS constellation integrity performance is better than 1x10-4 per hour for the probability of unalerted misleading signal information (UMSI) with the assumption that there are 10 satellites in view. This is based on the U.S. Government commitment to maintain an integrity performance level of better than or equal to 1x10-5 per hour per satellite UMSI probability as documented in the Global Positioning System Standard Positioning Service Performance Standard. Beyond this minimum "threshold" level of integrity performance, there is also an "objective" level of integrity performance specified in the GPS 800 series of specifications and the GPS Capabilities Description Document (CDD) for the GPS III satellites and OCX. This objective level of integrity performance is three orders of magnitude better than the threshold level of integrity performance. If the objective level of integrity performance of 1x10-7 per hour probability of UMSI assuming 10 GPS III satellites used in the position solution (i.e. probability of UMSI of 1x10-8 per hour per satellite, allocated between the
Proceedings Title
Proceedings of the 2013 ION GNSS meeting
Conference Dates
September 16-20, 2013
Conference Location
Nashville, TN
Conference Title


augmentation system, Global positioning system (GPS), Integrity, receiver autonomous integrity monitoring (RAIM)


Weiss, M. , Miles, C. , Kovach, K. , Dobyne, J. and Van, K. (2013), GPS Integrity Architecture Opportunities, Proceedings of the 2013 ION GNSS meeting, Nashville, TN (Accessed June 22, 2024)


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Created September 16, 2013, Updated February 19, 2017