Low-Profile Metamaterial-Based Adaptative Beamforming Techniques

Abstract

In this chapter, we will review recent research advances on beamforming and spatial multiplexing techniques using reconfigurable metamaterials (MTMs) and metasurfaces. This chapter starts by discussing basic principles and practical applications of transmission line-based metamaterials and planar metasurfaces, followed by their active versions that enable novel smart antennas with beam steering and beamshaping functions. We include detailed descriptions of their practical realizations and the integration with circuits and the radio-frequency (RF) frontend, which are used to adaptively and dynamically manipulate electromagnetic radiation. We summarize the state-of-the-art MTM/metasurface-based beamforming techniques and provide a critical comparison for their uses in the RF-to-millimeter-wave range in terms of cost, reconfigurability, system integratability and radiation properties. These techniques are expected to pave the way for the massive deployment of communication, radar, remote sensing and medical and security imaging systems.

Rayleigh angle incident ultrasonic beam shape design influence on reflected beam

“…A cross-fertilization between optics and acoustics in more recent times is found in the similarity between photonic crystals and phononic crystals or metamaterials in general. Recent advances in metamaterials [28][29][30][31][32][33][34][35][36][37][38] offer novel possibilities in transducer design, beam forming, and beam focusing. Provided with a new range of design possibilities, potential interest transpires in ultrasonic nondestructive testing and the occurrence of a guided waverelated beam effect, such as the Schoch effect, under unorthodox shapes of incident beams.…”

Programmable Beam-Steering Capabilities Based on Graphene Plasmonic THz MIMO Antenna via Reconfigurable Intelligent Surfaces (RIS) for IoT Applications

“…Due to their versatile qualities and properties, metasurfaces have found widespread use in recent years. It also has a wide range of applications such as perfect absorption applications [3], wireless power transfer [4], wave fronts with reflectionless sheets [5], polarization controllability [6], beam splitting and forming [7,8], total reflection or transmission layers [9,10], and its gained the researcher attentions in the wireless communications because of the total controllability and tunability of the wave propagations and its directions [11]. This tunability means that all the meta-atoms (unit cells) are controlled by switching it from ON to OFF state (modulated) by changing the external biasing gate voltage.…”