Like other satellite tracking systems, STAR can contain systematic observation biases, leading to errors in estiamted satellite trajectories. For example, the television transmitter positions given by the Federal Communications Commission (FCC) are typically only accurate to about a hundraed meters. If deployed overseas, these errors may be even greater. Estimating and removing these biases is a cost-effective way to improve the accuracy of resulting satellite orbit predictions. This paper describes the algorithm used to estiamte biases in transmitter position, receiver position, and receiver clock bias. it uses an iterative least squares approach. In the least squares fit, the root-mean-square of the residuals between the measured and the computed bistatic range rate is minimized. The computed values originate from accurate (+-5 meter) laer-ranged reference satellite ephemerides. Testing using real data indicates that, given a sufficient amount of observations with accurate reference orbits with which to compare, this algorithm can significantly improve on the accuracy of the published transmitter positions. This tool promises to be useful for STAR sensor calibration.
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