Abstract: A multifilar helix antenna includes helical antenna filaments, each filament having a square waveform pattern along its length, resulting in reduced axial length. A multifilar helix antenna according to the invention includes helical antenna filaments, each filament incorporating a microstrip spur-line band stop filter enabling multi-band operation.

Abstract: A multifilar antenna (200) comprises n spaced antenna filaments, where n is on integer greater than 1; a matching circuit (210) for matching the characteristic impedance of the antenna to that of a transmitting and/or receiving apparatus; a weighting circuit (240) for applying respective gain and phase adjustments to signals passed to or from the n filaments; switch means (310) associated with each filament for selectively altering the electrical length and/or interconnections of the filaments; means for detecting electrical properties of the multifilar antenna with respect to the frequency, polarisation and/or direction of propagation of a signal to be received or transmitted by the multifilar antenna and/or impedance matching of the antenna; and control means (230), responsive to the detective means, for controlling the operation of the matching circuit (210), the weighting circuit (240) and the switch means (310) to adjust the properties of the multifilar antenna (200) to suit better a current signal to be

Abstract: A multifilar antenna comprises n spaced antenna filaments, where n is an integer greater than 1; a matching circuit for matching the characteristic impedance of the antenna to that of a transmitting and/or receiving apparatus; a weighting circuit for applying gain and phase adjustments to signals passed to or from the n filaments; switch means associated with at least some of the filaments for selectively altering the electrical length and/or interconnections for the filaments; means for detecting electrical properties of the multifilar antenna with respect to the frequency, polarization and/or direction of propagation of a signal to be received or transmitted by the multifilar antenna and/or impedance matching of the antenna; and control means, responsive to the detecting means, for controlling the operation of the matching circuit, the weighting circuit and the switch means to adjust the properties of the multifilar antenna to suit better a current signal to be received or transmitted.

Abstract: A channel allocation and assignment method and system in which users are prioritised for channel allocation according to the mean SINR on their current channels. A channel is assigned to a user if the SINR on that channel exceeds a threshold value.

Abstract: An antenna combiner for combining wideband antenna signals produced by a plurality of antenna elements of an adaptive antenna. The combiner includes a narrowband combiner which is used to derive weights from the wideband antenna signals. These weights are applied to the wideband antenna signals and the weighted signals are combined to form a composite signal.