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In a satellite cellular communication system (10), a phased array antenna (41) includes a dynamic beamformer (50) that provides individual antenna beams (35) within which communications with subscriber units (26) take place. The satellites (12) are located in several orbits (14). As the satellites m

In a satellite cellular communication system (10), a phased array antenna (41) includes a dynamic beamformer (50) that provides individual antenna beams (35) within which communications with subscriber units (26) take place. The satellites (12) are located in several orbits (14). As the satellites move with respect to Earth's surface, each of the antenna beams is stepped backward (104) to compensate for the satellites movement. After each satellite travels a distance equal to a predetermined portion of the satellites' spacing in the orbit, each satellite's antenna beams are stepped forward (116) to replace the previous satellite's footprint. Accordingly, cell-to-cell hand-off is not required for subscriber units communicating within an antenna beam.

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[ What is claimed is:] [1.] In a phased array antenna adapted for use on a satellite that moves with respect to Earth's surface, a method of stepping a plurality antenna beams, said plurality of antenna beams forming a footprint region on Earth's surface, said satellite having a memory for storing f

[ What is claimed is:] [1.] In a phased array antenna adapted for use on a satellite that moves with respect to Earth's surface, a method of stepping a plurality antenna beams, said plurality of antenna beams forming a footprint region on Earth's surface, said satellite having a memory for storing first and second sets of beam forming coefficients therein, the method comprising the steps of:stepping back each antenna beam of said plurality to compensate for movement of said satellite; andstepping forward each antenna beam of said plurality a portion of a distance across said footprint region after repeating the stepping back step a predetermined number of times,wherein prior to the stepping back step, the method includes the steps of retrieving said first set of beam forming coefficients from said memory, and providing said first set of beam forming coefficients to a controller to control a phase and amplitude of said antenna beams, said first set of beam forming coefficients calculated to step each antenna beam back to compensate for said movement of said satellite, andwherein the stepping forward step includes the step of retrieving said second set of beam forming coefficients from said memory, and providing said second set of beam forming coefficients to said controller to control said phase and amplitude of said antenna beams, said second set of beam forming coefficients calculated to step said antenna beams forward said distance.