Mutual Coupling Reduction by Via-Loaded Notches

A phased array element based on the concept of antenna-as-package is proposed. The mutual coupling between antenna elements is analyzed. By introducing a via fence, a dielectric superstrate, and via-loaded notches, the sum mutual coupling is reduced through suppression and counteraction. As a result, the scan blindness is eliminated. Meanwhile, the effective bandwidth and cross-polarization suppression of the antenna while scanning are improved by 30% and 12 dB, respectively.