1D and 2D Left-Handed Materials Loaded with Circularly Coupled Ring-Circular

This article proposes a new type of circularly coupled left-handed (LH)structure. The proposed LH unit cell structure in one-dimension (lD)consists of a ring-circular metal patch loaded with two separated metal strips for the enhancement of coupling capacitance and magnetic resonance. In order to make the designed LH structure applicable to more occasions, the 1D LH unit cell is transformed into the one in two-dimension (2D)with four-cycle coupling structure. For a two-unit MIMO antenna loaded with the 1D LH structure, the simulation presents that a dual-band resonance, with two operating frequencies of 3.45 GHz and 4.95 GHz, is accessed from the original single-band one. And the isolation between the two units is obviously improved in the two bands for the designed antenna with 1D LH loading, meeting the requirements of WLAN /WIMAX and 5G applications.