A Q-GERT simulation model was designed to estimate the replenishment phase for the Global Positioning System using the original block buy of 28 satellites. Block I satellites were not considered in the study. The model determines the best fixed launch schedule without replenishment to find out when the initial constellation falls below 18 satellites. Additionally, the model was modified to determine the best fixed launch schedule that would maintain the constellation at 21 functional satellites 99% of the time. Sensitivity analysis was performed on the parameters of satellite design life and reliability through final orbit insertion. Satellite availability curves were used to show the number of operational satellites over time. Point availability curves were used to display the fraction of 21 satellites available each month of operation. A satellite attrition analysis was performed by selecting up to three satellites for deletion and evaluating coverage over the major land areas.


    Access

    Access via TIB

    Check availability in my library


    Export, share and cite



    Title :

    Replenishment Phase Study for the NAVSTAR Global Positioning System


    Contributors:

    Publication date :

    1984


    Size :

    120 pages


    Type of media :

    Report


    Type of material :

    No indication


    Language :

    English




    NAVSTAR GLOBAL POSITIONING SYSTEM

    MARTEL, JOHN | AIAA | 1981


    NAVSTAR Global Positioning System

    R. T. Schwab | NTIS | 1988


    Navstar/Global Positioning System

    Ananda, M. | NTRS | 1982


    The Navstar global positioning system

    Logsdon, Tom | TIBKAT | 1992


    The Navstar global positioning system

    Logsdon, Tom | SLUB | 1992