Design and Optimization of a Monolithic Thinned Dielectric Superstrate for Performance Enhancement in DRAA

In this letter, an innovative methodology is presented for the design of a monolithic thinned dielectric superstrate (TDS) aimed at enhancing the gain and minimizing the sidelobe levels (SLLs) associated with dielectric resonator antenna arrays (DRAAs). A novel configuration of the monolithic TDS is meticulously analyzed and subsequently integrated with a 1 × 2 element DRAA operating in the C-band spectrum. This integration is primarily done to align the radiated electric fields (EFs) phase, which culminates in enhanced antenna characteristics. The design and optimization of the proposed TDS are systematically executed using the differential evolution algorithm, specifically utilizing the thinning technique. Electromagnetic (EM) simulations and measurement studies are performed to elucidate the efficacy of the developed methodology. Preliminary findings from the EM simulations indicate that introducing the proposed TDS yields a significant performance enhancement. To be precise, the superstrate enables a gain enhancement of 4 dBi and an SLL decrement of 5 dB over a frequency bandwidth of 300 MHz relative to configurations devoid of the superstrate. Significantly, the observed measurements validate the proposed design strategy, aligning well with simulation results and confirming its practical efficacy and viability. In essence, this innovative design offers a notable enhancement in DRAA performance without necessitating any escalation in design complexity or spatial dimensions.