Dielectric lens focused scanning beam antenna for satellite communication system

摘要

A method and apparatus for providing a plurality of beams (30) transmitted and received from positions in low Earth orbit (11) for communicating directly with a plurality of portable, mobile and fixed terminals and gateways is disclosed. A plurality of scanning beam antennas (28) is deployed on each satellite (12) within a constellation (10) of satellites placed in low Earth orbit (11). Each one of said plurality of scanning beam antennas (28) simultaneously receives and transmits a plurality of beams (30), each of which beams (30) illuminates cell (26) in an Earth-fixed grid (20). The beams (30) are formed by each scanning beam antenna (28) and are focused on the cell (26) by a dielectric lens (60). A preferred embodiment uses a Luneberg spherical lens (60). Each beam (30) is electronically shaped and steered to keep the cell (26) of the Earth-fixed grid (20) within the beam footprint (50).