A novel planar, broadband, high gain lateral wave antenna array for body scanning applications

Abstract

Three-dimensional body scanning systems are increasingly used in sensitive public areas such as airports. By providing a high resolution image of a person from all sides, it is possible to detect potential metallic, ceramic and explosive threats. For these systems, it is essential to design broadband antennas with a fan beam, highly directional radiation in one plane and wide in the other plane, and characterized by phase center stability as a function of frequency. In this paper, the planar lateral wave antenna (LWA) array is proposed to achieve these radiation requirements. The LWA has two critical shortcomings: the flaring part and the dielectric matching layers (MLs), to operate over very broad frequency bands. In this work, these shortcomings are overcomed by forming a connected array of planar LWAs to improve broadband performance and by applying necessary perforations on the dense dielectric lens antenna to create different effective relative permittivity regions. An eight element connected and perforated LWA array is designed to operate in the 8-24 GHz frequency band. The drilled holes are proved to play a similar critical role of MLs in internal reflection suppression. The results emphasize all crucial demands for body scanning systems.