Series-Fed Printed Dipole Array Antenna

In this paper, we propose a high-gain series-fed eight-element printed dipole array antenna. Each dipole has the same size, the spacing between each dipole is identical, and the dipoles are connected in a series with a coplanar stripline. Broadband impedance matching is achieved with the balun, which consists of two slot lines of different lengths and widths on one side of the substrate and a tapered microstrip line on the other side of the substrate. The impedance bandwidth of the eight-element printed dipole array antenna is 34.3%, and the gain is 9.2-13.3 dBi. The radiation patterns exhibit endfire characteristics. The overall size of the designed array antenna is $15\times0.254 \times 47.8\mathrm{mm}^{3}(1.4\times \ 0.024\times4.5\lambda_{0}^{3})$.