An algorithm, combining velocity/height estimates, obtained from an airborne body fixed-image shift estimator with auxiliary onboard measurements and sparsely stored terrain profile information constitutes an entirely passive autonomous navigation system suitable for moderate-g flight missions. Two versions are addressed. The naive estimator, in which altitude estimates are multiplied by velocity/height estimaters, yields ground velocity. Position, obtained by integration, diverges with time. The extended Kalman filter (EKF) version, in which velocity and position are defined as state-space components, locks on the stored terrain profile and does not diverge with time. It degenerates into the naive estimator if the terrain is completely flat. Numerical examples indicate excellent performance potential of the EKF estimator.
|Original language||English (US)|
|Number of pages||17|
|Journal||IEEE Transactions on Aerospace and Electronic Systems|
|State||Published - Sep 1986|
ASJC Scopus subject areas
- Aerospace Engineering
- Electrical and Electronic Engineering