A High-Gain and Wideband Series-Fed Angled Printed Dipole Array Antenna

Abstract

In this communication, we have proposed a nonuniform series-fed angled dipole array antenna with a high gain, a wide bandwidth, a good sidelobe level (SLL), and a high front-to-back ratio characteristics. The proposed array antenna structure consisted of eight dipole elements, and each dipole was connected to a parallel stripline printed on the front and back sides of the substrate. From the first dipole element near the ground plane to the eighth dipole element at the end of the parallel stripline, the length of each dipole was reduced by ΔL <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</sub> . As with dipole length, the spacing between the dipole elements decreased by ΔS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</sub> from each previous dipole spacing. Compared to uniform array antennas, the impedance and gain bandwidths were greatly increased, and the SLL and front-to-back (F/B) ratio characteristics were improved. The proposed array antenna had an |S <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> | <; -10 dB, an impedance bandwidth of 23.3-51.0 GHz, and a 3 dB gain bandwidth of 22.0-44.0 GHz. At 28 GHz, the E- and H-plane SLLs of the proposed array antenna were -24.1 and -18.8 dB, respectively. The F/B ratio of the proposed antenna was less than -30 dB.