A Corrugated Printed Dipole Antenna With Equal Beamwidths

A corrugated printed dipole antenna with equal beamwidths in the principal planes is proposed, designed, and evaluated. Orthogonal stubs are added to the dipole arms to equalize its radiation patterns. They also reduce the size of the dipole arms. The antenna is designed to operate at 3 GHz, and has dimension of 36 × 80 × 1.58 mm
³
. The -10 dB S 11 bandwidth of the antenna is from 2.75 to 3.62 GHz, i.e., 27.3%. The E- and H-plane radiation patterns of the antenna are nearly equal up to 135
^°
from the boresight. To confirm the simulation results, the antenna is fabricated and tested, showing good agreement between simulation and measurement results. Its performance as a feed on a deep reflector, with f/D = 0.25 and D = 45 cm is also studied, where f is the focal length of the reflector and D is its diameter. It provides an enhanced bandwidth of 29.6%, equal E- and H-plane radiation patterns of the reflector, and a gain of 21.4 dBi or an efficiency of 69%. The reflector is only 4.5 λ0 in diameter and would suffer significant blockage losses with conventional waveguide feeds. The proposed feed causes negligible blockage, and provides a respectable efficiency. It is a suitable feed for small symmetric reflectors.