Ultra‐Low Profile Broadband Printed Dipole Antenna With Gap and Vertical Asymmetric Printing for S‐Band Applications

ABSTRACT This paper proposes a novel low‐profile broadband printed antenna. It consists of two FR4 dielectric substrates, each printed on one side with different radiation units. The upper radiation element is a ‐shaped bent dipole, while the lower is a ‐shaped bent dipole. There is no overlap between the two in the vertical direction. Additionally, the shape of each arm is altered to enhance the radiation performance. A stepped impedance converter makes the connection between the feedline and the arms to improve the broadband characteristics of the antenna. A gap is left between the top and bottom plates to introduce an air layer to enhance the antenna radiation performance. The antenna has been subjected to manufacturing and testing, and the results obtained are consistent with those predicted by the simulation. The return loss of the proposed antenna is less than −10 dB in the frequency range of 2.69–3.22 GHz, and it exhibits an ultra‐low profile.