Availability Modeling of Military Precision Approach and Landing Systems

Ian Gallimore, Jerry Wright and Greg Johnson

Abstract:	System availability is a Key Performance Parameter (KPP) for the Joint Precision Approach and Landing System (JPALS). This paper examines GPS landing system availability as a function of a number of key design and environmental parameters. The design trade space for a military GPS landing system is described, along with the modeling approach used to investigate the effect of each design parameter. Particular attention is given to the choice of GPS positioning algorithms and their implementation in the model. A unique feature of the model is the method to compute system availability when using the Relative Kinematic Carrier Phase Tracking (RKCPT) positioning technique following ambiguity selection. Results are then presented to illustrate the use of the system availability model to investigate the various design trades. The following specific effects are investigated: 1) variation in GPS sensor accuracy; 2) selection of positioning algorithm; 3) variation in satellite failure rates; 4) variation in the critical satellite threshold; 5) jamming; 6) outages; and 7) ship motion and structure blockage. Where appropriate, results are presented for both the Shipboard Relative GPS (SRGPS) and the Local Differential GPS (LDGPS) variants of the JPALS system.
Published in:	Proceedings of the 13th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GPS 2000) September 19 - 22, 2000 Salt Palace Convention Center Salt Lake City, UT
Pages:	1290 - 1300
Cite this article:	Gallimore, Ian, Wright, Jerry, Johnson, Greg, "Availability Modeling of Military Precision Approach and Landing Systems," Proceedings of the 13th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GPS 2000), Salt Lake City, UT, September 2000, pp. 1290-1300.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In