A Planar Circularly-Polarized Wide-Angle Scanning Phased Array With Aperiodic Distributed and Randomly-Rotated Elements

In this letter, a planar aperiodic wide-angle scanning phased array with circular polarization is designed and presented. 64 elements are nonuniformly arranged and randomly rotated to reduce sidelobe level (SLL) and deterioration of axis ratio (AR) across the wide-angle scanning range. A rapid analysis for the far-field characteristics, including realized gain and AR at steering direction, is conducted correctly based on the near-field Euler rotation and the non-uniform fast Fourier transformation (NuFFT) techniques. Such an array configuration, including element position distribution and rotation strategy, is achieved by multi-objective optimization. Finally, the designed array is fabricated and experimentally validated. The measured results indicate that the array achieves a maximum scanning angle of
$60^\circ$
in both
$xoz$
and
$yoz$
planes at 5.75GHz with its SLL and AR below -10dB and 3dB, respectively.