A Compact Single Layer Orthogonal Polarized Yagi-Like Directional Antenna

A compact Yagi-like directional antenna is presented based on a slot loop excitation. Two orthogonally polarized beams are generated by orthogonally feeding the slot using two microstrip lines. Both the horizontally polarized (HP) and the vertically polarized (VP) beams constitute an omnidirectional radiation patterns that are made directional by using two complementary slot reflector elements. The proposed antenna has a measured bandwidth of 330 MHz (3.56-3.89) targeting the WiMAX band. The antenna is compact with a total board size of 35 × 40 mm
²
Both end-fire directional beams have a minimum gain of 3.8 dBi and front-to-back ratio (FBR) of 6 dB. The efficiency of the antenna is 94% for both ports.