A Compact Yagi–Uda Antenna With Enhanced Bandwidth

A three-element compact Yagi-Uda antenna is pro posed that maintains a high absolute gain and low VSWR over a 10% fractional bandwidth with an element spacing of 0.053λ. The proposed Yagi-Uda antenna uses a director and reflector to create a dual resonance and approach superdirectivity at each resonant frequency. By adjusting the reflector and director's resonant frequency, the gain and bandwidth of the antenna can be maximized. The driven element has one folded arm to increase the impedance of the antenna. The reflector and director elements are bowtie de signs to increase the bandwidth. The measured impedance and gain agrees well with the computational model.

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