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Pajerski, R. S.

Publications and source records attributed to Pajerski, R. S..

Automated Orbit Determination System (AODS) requirements definition and analysis

The requirements definition for the prototype version of the automated orbit determination system (AODS) is presented including the AODS requirements at all levels, the functional model as determined through the structured analysis performed during requirements definition, and the results of the requirements analysis. Also specified are the implementation strategy for AODS and the AODS-required external support software system (ADEPT), input and output message formats, and procedures for modifying the requirements.

Waligora, S. R.

The role of autonomous satellite navigation in the NEEDS program

A number of applications of autonomous satellite navigation are discussed. They include the onboard annotation of all experimental data and the onboard correction of imaging data. The accuracy levels required for each function are presented. Two alternative techniques for achieving autonomous satellite navigation are considered. One technique utilizes data from the Global Positioning System (GPS). The other approach utilizes data from a geosynchronous relay satellite system such as the Tracking and Data Relay Satellite System (TDRSS). The TDRSS approach makes use of one-way range and Doppler data along with a time transfer mechanism. Comparative accuracy levels for the onboard determination of position, velocity, and time based upon the GPS and TDRSS approaches are presented.

Fuchs, A. J.