Tracking receiver design for the electronic beam squint tracking system in the maritime mobile environment

One method of reducing the overall cost of a shipborne satellite terminal is to dispense with the stabilised platform. This is only permissible in a situation in which the dynamic performance of the tracking system can compensate directly for the motion of the ship. Two techniques have been proposed to solve this problem. The first involves the use of optimal estimation techniques which utilise both the available tracking information and the instantaneous platform orientation to provide steering information for the antenna. This is obviously a complex technique as it requires a separate high-speed microprocessor system to provide information on the ship's dynamics. The second, a new technique, is the 'electronic beam squint' (EBS) tracking system under investigation at Bristol University. This system can be demonstrated to counter the characteristic roll and pitch dynamics of a maritime vessel purely by a closed-loop tracking technique. The authors investigate the beam squint technique from the viewpoint of the tracking receiver in a maritime environment, together with the more general problems experienced by tracking receivers in this situation.<>