Estimation of Decayed Satellite Reentry Trajectories
Abstract
A technique was developed for estimation of decayed Earth satellite reentry trajectories to provide impact locations for debris search requirements. The technique used a linearized differential-corrector as an extension of existing orbit estimation methods. The reentry observations consisted of angular, infrared measurements from orbital sensors. An eight dimension state vector was used with components for position, velocity, a ballistic parameter and the scale height from an isothermal density model. Simulated data runs identified the uncertain dynamics of the true reentry process as the most significant impact on estimator performance. The uncertain dynamics pose significant problems for standard model compensation methods such as adaptive pseudo-noise compensation or more sophisticated techniques such as statistical linearization or higher order filters. The adaptive determination of an 'ad hoc' scalar fading memory parameter was used to modify the estimator-computed state covariance matrix. The bias in the state estimates were well within the variance from this modified covariance matrix. The standard deviations from the modified covariance compare closely to the root-mean-square errors of the true solution over a range of simulated truth model data. The uncertainties associated with the impact locations are anticipated to be at least one order of magnitude better than propagation of the final orbit estimation covariance matrix to Earth impact.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 08, 1981
- Accession Number
- ADA111231
Entities
People
- Raymond H. Barker Jr.
Organizations
- Air Force Institute of Technology