Abstract: A data communication system has a station that includes multiple antenna elements. The station communicates to the antenna elements by way of digital data channels. Each antenna is connected to an RF module that receives data by way of a corresponding digital data channel, encodes and transmits the data. Adaptive beamforming may be performed for interference mitigation. Embodiments use the strength of pilot signals and/or error vector magnitudes as cost functions for an adaptive beamforming alogorithm such as optimum combining. Unused sub-carriers may be applied to provide in-band communication to facilitate channel switching, data reallocation and other interference mitigation strategies.

Abstract: Novel reconfigurable antennas are provided which may be used to accommodate the requirements for wideband multi-standard handheld communication devices. It is shown that using a shape memory alloy spring actuator, the height of a helical antenna and therefore the pitch spacing and angle can be varied. This can in turn tune the far-field radiation pattern and gain of the antenna dynamically to adjust to new operating conditions. The radiation pattern can further be directed using a two-helix array. Finally, a helical antenna embodiment is implemented and measured using a shape memory alloy actuator. Measurement results confirm that while keeping the centre frequency constant, gain tunability can be attained using this structure.

Abstract: Novel reconfigurable antennas are provided which may be used to accommodate the requirements for wideband multi-standard handheld communication devices. It is shown that using a shape memory alloy spring actuator, the height of a helical antenna and therefore the pitch spacing and angle can be varied. This can in turn tune the far-field radiation pattern and gain of the antenna dynamically to adjust to new operating conditions. The radiation pattern can further be directed using a two-helix array. Finally, a helical antenna embodiment is implemented and measured using a shape memory alloy actuator. Measurement results confirm that while keeping the centre frequency constant, gain tunability can be attained using this structure.

Abstract: A data communication system has a station that includes multiple antenna elements. The station communicates to the antenna elements by way of digital data channels. Each antenna is connected to an RF module that receives data by way of a corresponding digital data channel, encodes and transmits the data. Adaptive beamforming may be performed for interference mitigation. Embodiments use the strength of pilot signals and/or error vector magnitudes as cost functions for an adaptive beamforming alogorithm such as optimum combining. Unused sub-carriers may be applied to provide in-band communication to facilitate channel switching, data reallocation and other interference mitigation strategies.

Abstract: A variable helix antenna consisting of one or more conductors affixed to a furled dielectric sheet. The antenna beam being steerable by furling and unfurling of the dielectric sheet either rotationally, axially or by a combination of both. Multiple interleaved dielectric sheets may be used for multifilar embodiments and matching and compensation elements may also be provided on the dielectric sheet.

Abstract: A vehicle inspection facility comprises a horizontal base frame supporting a pair of brake testing sub-assemblies. Each sub-assembly comprises a driven roller and a companion roller, and includes means for rotating the driver roller for rotating the wheels of a vehicle being tested and means for measuring the braking force applied by the vehicle brakes against the driven roller. Also included is a vehicle suspension and steering testing assembly comprising a pair of horizontal supporting surfaces for supporting the vehicle front wheels and including means for producing reciprocal motion of the supporting surfaces along perpendicular directions to determine the degree of "play" of the wheels.