Patent ID: 7953065
Filing Date: 2011-05-31
Classification: H04B,H04W

Abstract:
1. A point to multipoint device for use in a wireless network to provide wireless communication with a plurality of telecommunications units, for communication from the point to multipoint device to the telecommunications units, the point to multipoint device being operable to employ multiple sets of beams, at any point in time one set being used, the point to multipoint device comprising: beam set generation logic for generating the multiple sets of beams arranged into one or more groups, each group comprising one beam from each set, within each group the beams of that group being orthogonal with respect to each other, and each beam within each set being generated randomly with respect to other beams in that set; an interface for receiving a synchronisation signal issued to all point to multipoint devices in the wireless network; beam switching logic for determining, having regard to the synchronisation signal, switch times at which the point to multipoint device switches from one set of beams to another set of beams, the switch times being the same for all point to multipoint devices in the wireless network; and an antenna array controlled by the beam switching logic for producing at any point in time one of the sets of beams for transmitting data forming the communication to the telecommunications units; wherein the beam set generation logic is operable for each group: to generate an N×N random matrix, where N is the number of antennae in the antenna array used to generate the beams of that group, and N is equal to or greater than the number of beams in that group; to generate from the N×N random matrix an N×N unitary matrix; and to select a different column of the N×N unitary matrix to represent each beam in the group, where each entry in the column defines a beam weight to be used by a particular antenna of the antenna array when generating the associated beam.