Design of Out- of-Phase Power Divider Fed Endfire Antenna with Wide Bandwidth

A novel wideband periodic endfire antenna is presented. Broad bandwidth is realized by using a parallel strip line (PSL) feed and dipole elements. A coupling between two microstrip lines on the top and bottom substrate layers through a slot in the common ground plane, and a transition from two microstrip lines to a parallel stripline are used to achieve an wideband operation. The regular dipole shape is modified to a quasi-rhombus shape by adding two triangular patches. Using two dipoles helps maintain stable radiation patterns close to their resonance frequencies. A modified array configuration is proposed to further enhance the antenna radiation characteristics and usable bandwidth. The proposed antenna provides endfire radiation patterns with high gain, high front-to-back (F-to-B) ratio, wide beamwidth in a wide bandwidth of the 130%.