Patent ID: 8049667

Claim:
An antenna system, comprising: a mast having an axis and arranged to be fixed at a certain position with respect to a surrounding ground area, and to extend vertically above the ground area; a number (N) of antenna units each including a base supported along the length of the mast with a determined spacing from one antenna unit to another antenna unit in the axial direction of the mast; each antenna unit includes a number of antenna elements mounted on and disposed about the periphery of the base of the unit for responding to radio frequency (RF) signals within a certain wavelength band, a number of mode ports on the antenna unit including a primary pattern mode port and one or more auxiliary pattern mode ports, and an associated phasing network disposed on or within the base of the antenna unit and coupled to the antenna elements on the base of the unit, wherein the phasing network is configured to produce a number (M) of mutually orthogonal antenna pattern modes including a primary pattern mode at the primary pattern mode port of the antenna unit, wherein the primary pattern mode corresponds to a desired signal response in the absence of an interfering signal incident on the antenna system, and one or more auxiliary pattern modes at corresponding ones of the auxiliary pattern mode ports of the antenna unit, wherein the auxiliary pattern modes have azimuthal RF carrier phase progressions that differ from one another and from that of the primary pattern mode; M radio frequency (RF) power dividers each of which is associated with a different one of the M antenna pattern modes produced by the phasing networks of the N antenna units, wherein each power divider has N input ports each of which is coupled to the associated pattern mode port of a different one of the antenna units; the input ports of a first power divider are coupled to the primary pattern mode ports of the antenna units, and the first power divider is configured to produce at least a corresponding primary or reference beam at a reference port of the divider, and, optionally, an auxiliary beam at an auxiliary port of the divider, and the input ports of second power dividers are coupled to the auxiliary pattern mode ports of the antenna units, wherein the second power dividers are configured to produce corresponding auxiliary beams at corresponding auxiliary ports of the dividers; and an adaptive processor coupled to the reference port of the first power divider and to the auxiliary ports of the first and the second power dividers, wherein the processor is configured to combine the reference beam and selected ones of the auxiliary beams produced by the dividers to obtain a reception pattern for the antenna system having one or more nulls at determined angles in both elevation and azimuth to suppress interfering signals arriving at the antenna system at said angles.