Miniaturization design of log periodic dipole antenna based on dovetail structure

Abstract

Aiming at the problems of large size and small gain of log periodic dipole antenna (LPDA) in high frequency (HF), this article introduces miniaturization technology to design a miniaturized HF broadband LPDA unit antenna with high gain. In this article, a dovetail structure is designed for LPDA to greatly reduces its transverse size, and adopts a larger scale factor and a smaller spacing factor to reduce its longitudinal size. The effects of scale factor, spacing factor, oscillator angle, parallel oscillator and erection height on the impedance characteristics and radiation performance of dovetail LPDA are studied. Finally, the feasibility of dovetail LPDA is verified by simulation and experiment, which shows that the proposed antenna size is only 7.92 × 15.52 m2, voltage standing wave ratio is less than 1.8, and gain is more than 11 dBi. The proposed dovetail LPDA has high gain, wide bandwidth, and small size, which can work independently and can also be used as the unit antenna of HF broadband antenna array.