A Modified H-plane Horn Antenna In PCB Technology With Improved Efficiency

This paper presents a technique to enhance the antenna efficiency of a printed circuit board (PCB) based modified H-plane horn antenna. Improvement in antenna efficiency is obtained by correcting the phase error on the radiating aperture using a modified feed geometry. It also helps to improve input matching. This modification does not increase the overall rectangular dimension of the antenna when compared to a conventional H-plane horn antenna. As an example, a modified H-plane horn is presented for the 24-24.25 GHz ISM band. It increases the antenna efficiency by at least 30% over the conventional PCB-based horn. The best |S11| for a conventional horn in the same substrate which could be achieved is − 6 dB. In comparison, the modified horn provides a 10 dB matching bandwidth of at least 516 MHz. Other advantages are low side lobe levels and small 3 dB beamwidth.