Dot-Shaped 3D Range-Angle Dependent Beamforming With Discular Frequency Diverse Array

Abstract

A frequency diverse array (FDA) concept has drawn substantial attention in recent years because of its particular range-angle-dependent beam pattern. This interesting feature promises new opportunities and capabilities for antenna array applications, especially in beamforming. The dot-shaped beam pattern is also a new and exceptional phenomenon that can focus the transmit energy in a 3-D spatial region of interest. However, almost all of the works and studies in the literature with this title is related to the linear array geometry and involves range and one angle only. Therefore, the beam defined as dot-shaped is actually only 2-D and extends in one angle, thus breaking the dot shape. Moreover, to obtain such a beam shape, complex mathematical techniques and algorithms are used. In this study, a real 3-D dot-shaped beamforming is realized with discular FDA (DFDA) and outward radial frequency offsetting scheme. This study extends the research geometries of frequency diversity concept further by investigating the discular geometry in-depth. The theory, analysis, and the basic beam-steering properties of the DFDA is presented and compared with other geometries.