Miniaturized patch antennas loaded with complementary split-ring resonators and reactive impedance surface

Miniaturized patch antennas loaded with complementary split-ring resonators (CSRRs) and reactive impedance surface (RIS) are proposed and presented. The CSRR is incorporated on the patch to excite the antenna at a low CSRR resonance frequency. The RIS is inserted below the patch to miniaturize the antenna size and improve the antenna radiation performance. One antenna working at 2.4 GHz is first designed with a compact size around 0.099 λ₀ × 0.153 λ₀ × 0.024 λ₀. Then a dual-band antenna with orthogonal polarization is developed by simply adjusting the feeding position in order to excite the initial patch resonance. The antennas are fabricated and measured with the standard PCB process. The experimental results are in good agreement with the simulation.