Abstract:
In this paper, analysis on precise geostationary satellite orbit determination using spread
spectrum ranging measurements is performed. Adding to the communication system a
residue number system block to enhance its performance. The results are compared to
that provided from orbit determination using both dual RF-tone ranging from two
separate earth station locations and classical orbit determination using both angular
measurement and RF-tone measurements from an earth station.
A model for the spread spectrum ranging system is developed to be used in the orbit
determination process. Chaotic code generator is used instead of conventional PN code
generators in the spread spectrum ranging system. The performance of the system is
evaluated using both the chaotic and conventional code generators.
A Matlab programs are developed to perform orbit determination process and to
measure the bit energy to noise ratio required for the communication. The developed
programs take into account the dynamic model of the satellite orbit including various
orbital perturbations and simulate the path delay for ranging measurements including
clock offsets, thermal, ionosphere and troposphere noise. Acceptable results were
foreseen in comparison to the flight proven software tool.