Patent ID: 7088671
Filing Date: 2006-08-08
Classification: H04B

Abstract:
1. A method of communicating digital data information that is different for each of a plurality of user terminals from a central node transmitter at a central node, which is connected to an adjacent central node by a fixed communication link, to the plurality of user terminals located within a plurality of beam coverage areas produced by a multibeam antenna at the central node, using a set of mutually orthogonal channels for user terminals within a beam coverage area and reusing the same orthogonal channels for user terminals in other beam coverage areas, comprising the steps at the central node transmitter of: single-axis coding of digital data information to provide a sequence of real valued coded symbols; interleaving coded symbols among a plurality of data groups, thereby producing a user interleaved signal for each associated user terminal; assigning a plurality of user interleaved signals to a particular orthogonal channel; precoding with complex matrix multiplications of a plurality of user interleaved signals that are assigned to the same orthogonal channel to provide a precoded signal vector; modulating the precoded signal vector to provide a plurality of quadrature modulated waveforms one for each of the associated beam coverage areas; combining modulated waveforms associated with different orthogonal channel assignments and associated with users in the same beam coverage area thereby producing a beam signal; transmitting beam signals from a multibeam antenna.