Coordinate Transformations-Based Antenna Elements Embedded in a Metamaterial Shell with Scanning Capabilities

Abstract

In this work transformation electromagnetics/optics (TE/TO) were employed to realize a non-homogeneous, anisotropic material-embedded beam-steerer using both a single antenna element and an antenna array without phase control circuitry. Initially, through theory and validation with numerical simulations it is shown that beam-steering can be achieved in an arbitrary direction by enclosing a single antenna element within the transformation media. Then, this was followed by an array with fixed voltages and equal phases enclosed by transformation media. This enclosed array was scanned, and the proposed theory was validated through numerical simulations. Furthermore, through full-wave simulations it was shown that a horizontal dipole antenna embedded in a metamaterial can be designed such that the horizontal dipole performs identically to a vertical dipole in free-space. Similarly, it was also shown that a material-embedded horizontal dipole array can perform as a vertical dipole array in free-space, all without the need of a phase shifter network. These methods have applications in scanning for wireless communications, radar, beam-forming, and steering.