A miniaturized frequency reconfigurable antenna with half-mode CRLH-embedded metamaterial arm

Metamaterial properties of a novel half-mode CRLH unit cell are investigated and hence a compact dual-wideband antenna is designed using an array of four unit cells. The negative refraction of the metamaterial cell is utilized to miniature the antenna. A via-free open stub, in combination with an interdigital capacitor, makes the half-mode CRLH unit cell. The proposed antenna operates at both C-band (6.2-6.8 GHz) and X-band (8.5-9.2 GHz). The dual-wideband antenna is enabled with frequency reconfigurability by incorporating RF PIN diode in its ground plane in the next design step. The ON-OFF conditions of the PIN diode electrically switch the antenna into dual-band and single-band modes, respectively. In OFF state of the diode, the antenna behaves as a monopole and operates in single-band mode resonating at C-band (5.9-6.5 GHz) only. The measured results of the fabricated sample are in good agreement with the simulated ones.