A Transverse Scanning Periodic Leaky Wave Antenna Loaded with Metamaterials

This paper proposes a lateral scanning periodic leaky-wave antenna based on meta-material loading. Leaky-wave antenna is a kind of traveling-wave antenna. Because of its unique radiation characteristics and excellent lobe scanning characteristics, leaky-wave antenna has always been a hot topic in the field of antenna research, and is widely used in radar, wireless communication and special applications in detection systems. In recent years, many studies have introduced the concept of metamaterials in the microwave field into the study of leaky-wave antennas, injecting new vitality into the study of leaky-wave antennas. A significant advantage of metamaterial leaky-wave antenna is that it can realize continuous frequency scanning from backward to forward in the fundamental mode, including normal radiation without radiation deterioration. The optimization of antenna parameters such as gain is an important aspect of all antenna design. In the context of leaky-wave antennas (LWAs), artificial metamaterial structures can realize the control of electromagnetic waves because of their specific dielectric constant and magnetic permeability, so that leaky-wave antennas can have better gain. In this paper, in order to improve the directionality of the side beam, a pair-expansion structure is designed to realize lateral radiation, and metamaterial units are loaded at the center of the periodic element, which can improve the gain of the antenna without affecting the characteristics of antenna efficiency and return loss. The simulation results show that the overall size of the designed antenna is 154 × 30 × 1.2 mm³. The antenna can achieve effective radiation in the frequency band of 5.1 ~ 10.2 GHz. The beam scanning ability ranges from 60° to 140°. The gain can be increased by up to 1.6 dBi after loading metamaterial units.