Abstract: Beamforming system and method which includes an inverse beamformer with first ports and second ports, a beamformer with beam ports and antenna ports, and antennas. The inverse beamformer may receive transmit signals provided to first ports, generates intermediate signals based on the transmit signals, and output the intermediate signals from the second ports. The beamformer's beam ports may couple to the second ports and the antenna ports, and may receive the intermediate signals at the beam ports, generate antenna signals based on the intermediate signals, and output the antenna signals at the antenna ports. The antennas may each receive an antenna signal from an antenna port, and transmit the antenna signal into space. The inverse beamformer may generate the intermediate signals in a manner that is mathematically inverse to the beamformer's generation of the antenna signals so that the antenna signals approximate the transmit signals up to respective phase shifts.

Abstract: A beamformer is arranged to receive an input from a first antenna element and from at least one other antenna element and to generate at least a first and second output beam. The first and second output beams are combined at a connecting port such that signals received at the first antenna element are constructively combined at the connecting port and signals received at another antenna element or elements are destructively combined at the connecting port, so that a receiver connected to the connecting port may receive signals from the first antenna element and may not receive signals from the other antenna element or elements. The arrangement may also be used to transmit a signal which is fed into the connecting point from the first antenna element and not from the other antenna element or elements.

Abstract: A beamformer is arranged to receive an input from a first antenna element and from at least one other antenna element and to generate at least a first and second output beam. The first and second output beams are combined at a connecting port such that signals received at the first antenna element are constructively combined at the connecting port and signals received at another antenna element or elements are destructively combined at the connecting port, so that a receiver connected to the connecting port may receive signals from the first antenna element and may not receive signals from the other antenna element or elements. The arrangement may also be used to transmit a signal which is fed into the connecting point from the first antenna element and not from the other antenna element or elements.

Abstract: Embodiments of the invention are concerned with improvements to antenna systems, in particular beamforming antenna systems. Embodiments provide an improved beamformer arrangement for receiving and transmitting of signals by antenna elements. Embodiments are particularly well suited to use for transceiving of radio signals by base stations, such as are commonly found in cellular networks.

Abstract: A sea surface antenna comprises a cylindrical tube of metallic material 13 on a dielectric former. The tube has a longitudinal slot shorted at each end and coupled at its midpoint to a coaxial feed. The slot is bridged by two groups of capacitances each group being distributed along a respective half of the slot. The length of the antenna is less than 0.25 ? and the diameter of the antenna is less than 0.02 ?, where ? is the free space wavelength at the operating frequency. The antenna is dimensioned so as to operate in an evanescent mode at a resonant frequency less than the cut-off frequency.

Abstract: In accordance with the present invention, there is provided a linear antenna array comprising a number of antenna elements and a feed network, wherein the feed network is operable to apply the cumulative effect of a progressive phase shift across the antenna elements of the array and a stepped complex operator shift to selected groups of antenna elements of the array, whereby a down tilted and null-free coverage by a resulting radiation pattern can thereby be provided. The complex operator can be phase, amplitude or a combination of both. The antenna array can be a layered antenna and the phase shifts in the feed network can be provided by differing length transmission paths, whilst any amplitude shift can be provided by unequal power dividers. In order to provide no down tilt and just null fill-in, then the progressive phase shift can be specified to be zero.