Advanced array signal processing algorithms for DoA estimation of satellites and launchers

Orbiting satellites and other spatial vehicles have complex trajectories that can usually be precisely approximated with analytical or numerical trajectory estimation algorithms. However, some scenarios, such as LEOP (Launch and Early Orbit Phase) or during critical manoeuvres, present greater angular uncertainty. During these, large dish antennas used for TT&C (Telemetry, Tracking & Command) may have too narrow a beamwidth to perform a reliable and fast acquisition. A novel acquisition aid system based on distributed array elements placed on the rim of the main antenna´s reflector has been implemented and successfully tested with real satellite signals. This paper analyses the subjacent digital signal processing algorithms required for DoA (Direction of Arrival) estimation, and shows simulations and field results which validate their performance.