E-Plane Beam-Steerable Patch Array With Enhanced Directivity Using Nonradiating Resonator

This letter presents an E-plane beam-steerable three-element patch array with the nonradiating resonators (NRRs) inserted between the driven element and the parasitic elements. The additional NRRs can provide a large maximum phase difference between the adjacent radiating elements to improve the steering range, achieve a large induced voltage on the parasitic elements to improve the directivity, and increase the distance between the two adjacent radiating elements to narrow the half-power beamwidth. By tuning the resonant frequencies of the NRRs and the parasitic elements using the varactors, the beam of the array can continuously scan around the boresight direction. Finally, a demonstration is designed, fabricated, and tested. The measured (simulated) results show this patch array operated at 2.41 GHz (2.4 GHz) can scan from +26° to −29° (+31° to −31°) with the realized gain varying from 6.3 to 8.8 dBi (8.1–10.4 dBi).