A Low-Profile Inverted F Element Array Backed by an EBG Reflector

An array composed of a pair of inverted F elements above an EBG reflector is constructed and analyzed using the finite-difference time-domain method (FDTDM). The array is characterized by inverted F elements that have an extremely small height above the surface of the EBG reflector (0.03 wavelength). The analysis is performed for two cases (CASE I and CASE II). The two inverted F elements for CASE I are excited in phase, and those for CASE II are excited 180 degrees out of phase. It is found that the radiation fields from the array for these two cases have orthogonal polarizations in the direction normal to the array plane. It is also found that the VSWR is relatively wide: approximately 10% for CASE I and 21% for CASE II