A Multiple Hypothesis Skymark Positioning (MHSP) algorithm is developed to conduct satellite identification and geolocation for GPS-denied navigation. The primary application is intended to be for initialization of a Skymark navigation system operating in open ocean. The MHSP algorithm uses a multiple hypothesis tracking framework to efficiently evaluate many possible satellite identification options across multiple temporal sightings, which enables the MHSP to provide a robust initialization even when the initial position of the system is unknown. The MHSP was evaluated using 800 Monte Carlo simulations and was shown to successfully converge to the correct satellite identification, and consequently the correct observer location, 100 percent of the time. The sensitivity of the MHSP to star tracker pointing accuracies was also evaluated and it was shown that the MHSP converges to the correct satellite identification even when the pointing error is increased to 500 microradians albeit with more observations. Based on the Monte Carlo simulation results, the MHSP was determined to be an effective initialization tool for Skymark based navigation systems in GPS-denied environments on the open ocean.
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