Subarray Implementation via Phase Compensation in Circularly Polarized Arrays

In this article, a universal methodology for implementing subarray architecture in an actual array antenna is proposed. By rotating the circularly polarized (CP) subarrays, the repetitiveness of the subarrays is ensured, thereby enabling the modularization of the subarrays as their feed layers are identical. Leveraging the characteristic of electromagnetic (EM) waves wherein the polarization orientation of the CP EM wave rotates in accordance with the excitation phase, the disordered polarization orientations induced by the subarray rotations are adjusted and synchronized through phase compensation. To verify the feasibility of the proposed methodology, three synthesized subarrays are implemented, comprising an $8\times 8$ domino-like subarrayed planar array, a $16\,\times \,12$ L-octomino subarrayed planar array, and a 349-element polyhex-shaped circle planar array. To further verify the effectiveness of the proposed methodology, the 349-element circle planar array is fabricated, assembled, and measured. Numerical results indicate that the proposed method is a promising approach for subarray implementation, offering notable radiation performance and facilitating modularization.