A NOVEL COMPACT SPLIT RING SLOTTED ELECTROMAGNETIC BANDGAP STRUCTURE FOR MICROSTRIP PATCH ANTENNA PERFORMANCE ENHANCEMENT

A novel design of an electromagnetic bandgap (EBG) structure based on the uniplanar compact EBG (UCEBG) concept is proposed in this paper. The structure is realized by inserting split-ring slots inside two reversely connected rectangular patches, which is known as a split-ring slotted electromagnetic bandgap (SRS-EBG) structure. The bandgap properties of the EBG structure are examined by the suspended microstrip line and finite element methods (FEM). The achieved bandgaps have widths of 4.3 (59.31%) and 5.16 GHz (38.88%), which are centered at 7 and 13 GHz, respectively. The SRS-EBG is applied to enhance the performance of a single-element microstrip patch antenna (at 7 GHz) and a two-element array (at 13 GHz) configuration. A wider bandwidth is obtained with a better reflection coefficient level for the single element antenna; a reduction in mutual coupling of more than 20.57 dB is obtained for the array design. In both cases, the gain and radiation characteristics are improved. The results are verified by measuring the fabricated lab prototype, and a comparison with the computed results showed good agreement.