Novel reconfigurable antennas are provided which may be used to accommodatetherequirements for wideband multi-standard handheld communication devices. It isshown thatusing a shape memory alloy spring actuator, the height of a helical antennaand therefore thepitch spacing and angle can be varied. This can in turn tune the far-fieldradiation pattern andgain of the antenna dynamically to adjust to new operating conditions. Theradiation pattern canfurther be directed using a two-helix array. Finally, a helical antennaembodiment isimplemented and measured using a shape memory alloy actuator. Measurementresults confirmthat while keeping the centre frequency constant, gain tunability can beattained using thisstructure.
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