Deep-Space Optical Navigation Exploiting Multiple Beacons

Ground facilities relying on traditional radiometric tracking are reaching saturation due to the growth of satellites launched into space. As such, autonomous navigation is one of the main enabling technologies for sustainable deep-space missions. This paper tackles the deep-space optical navigation problem exploiting multiple beacons to estimate the observer position independently from ground. The paper derives the least-squares solution and the analytical covariance to the deep-space navigation problem exploiting multiple beacons. The perturbations in the line-of-sight directions as well as in the objects ephemeris are incorporated into the covariance formulation. Then, the geometrical interpretation of the perturbations models, the navigation solution, and the navigation covariance are elaborated. The sensitivity of the navigation accuracy to the number of beacons is assessed by virtue of a test case, showing the correspondence between the numerical and the analytical solutions. Eventually, the paper shows the comparison of the navigation accuracy exploiting multiple beacons against two optimal beacons.