Estimating attitude from signal-to-noise ratio at multiple ground-based receivers

This paper presents the implementation of an attitude estimation algorithm to be applied in multiple space-or Earth-based receiver platforms using signal-to-noise ratio from received transmissions from a single broadcasting satellite. A statistical method based on received signal samples is applied to estimate the incoming signal-to-noise ratio, which then facilitates the geometrical derivation of line-of-sight and boresight pointing estimates using geometric relations. The results of this deterministic approach show that at least three independent receivers with non-collinear lines-of-sight are necessary to obtain a three-dimensional boresight solution. Furthermore, an observability study is carried out along with sequential estimation for attitude/maneuver detection. Results indicate a dependence on a-priori knowledge of the bradcaster’s RF characteristics, as well the viability of estimating attitude via signal-to-noise ratio as a complement to additional space situational awareness approaches.