Design of a Wideband Highly Directive EBG Antenna Using Double-Layer Frequency Selective Surfaces and Multifeed Technique for Application in the Ku-Band

We have shown in previous works that the use of double-layer frequency selective surface (FSS) in the superstrate of an electromagnetic band-gap (EBG) antenna provides a radiation bandwidth improvement. Nevertheless, such an antenna is still not directive enough for some applications. To increase its gain, the antenna will be fed using the multisource feeding technique. This principle is applied to design a wideband highly directive antenna operating in the Ku-band. When the radiation bandwidth corresponding to the realized gain is equal to 14% for a maximal gain of 22.5 dB, 17% of radiation bandwidth is obtained for a maximal directivity of 23 dB.