Barometer-Free Aircraft Terrain-Aided Navigation System: Prototype Design and Flight-Test Validation

Milos Vesely, Jindrich Dunik, and Tomas Beda

Peer Reviewed

Abstract:	This paper deals with terrain-aided navigation (TAN) for aircraft. In particular, the radar-altimeter-based TAN (RATAN) recently developed by Honeywell laboratories is described and validated. The RATAN fuses data from inertial measurement unit, radar altimeter, and map, only, using a robust state estimator based the point-mass method and provides the estimate of the full navigation information including the three-dimensional position, velocity, attitude, and heading. As such, the RATAN is a all-weather navigator suitable for GNSS-denied environments, which was validated in the helicopter flight test campaign with trajectories flown in different altitudes above terrain, varying dynamics, and sensor properties. The RATAN provides consistent horizontal position estimate with accuracy below thirty meters in terms root-mean-square-error over a common terrain. Index Terms—terrain-aide navigation, GNSS-denied, state-space model, Bayesian estimation, flight test
Published in:	2025 IEEE/ION Position, Location and Navigation Symposium (PLANS) April 28 - 1, 2025 Salt Lake Marriott Downtown at City Creek Salt Lake City, UT
Pages:	1371 - 1379
Cite this article:	Vesely, Milos, Dunik, Jindrich, Beda, Tomas, "Barometer-Free Aircraft Terrain-Aided Navigation System: Prototype Design and Flight-Test Validation," 2025 IEEE/ION Position, Location and Navigation Symposium (PLANS), Salt Lake City, UT, April 2025, pp. 1371-1379.
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