Electronically Steerable Terminal Antenna (ESTA) project, phase 2

The feasibility of a full adaptative antenna terminal was considered, but such a terminal is too expensive for breadboarding and an electronically steerable antenna filling the gap between low gain and complex high gain terminals is proposed. The beam is steered towards the satellite following the inputs provided by the position and navigation instruments of the mobile. No moving parts are used. The manufacturing and testing of a maritime antenna prototype as well as the design of a lower complexity antenna for land mobile application were completed. Simple and advanced terminals were studied. Both include protection against multipath; the advanced terminals also include protection against interferences. Results for the maritime prototype are good enough and agree with expectations. The expected performances of the land antenna should be checked in a manufacturing project. The much lower level of complexity of this antenna compared to the maritime one, will result in a low price product with high performances, probably allowing voice communications without vocoders.