Channel Multiplexing in Wireless Terahertz Communications Using Orbital Angular Momentum States

TL;DR

This paper demonstrates the design and experimental validation of 3D-printed metamaterial phase plates for generating and multiplexing Orbital Angular Momentum states in terahertz wireless communications, enabling multiple data channels.

Contribution

It introduces a novel 3D-printed metamaterial phase plate design for generating OAM states and demonstrates multiplexing and demultiplexing in terahertz communication systems.

Findings

Successful generation of OAM states using 3D-printed phase plates

Experimental validation of multiplexing multiple OAM states

Theoretical simulation supporting experimental results

Abstract

We present design and experimental validation of the system for the generation of the Orbital Angular Momentum (OAM) states using 3D-printed low-loss metamaterial phase plates for application in the terahertz (THz) wireless communications. By azimuthally varying the hole pattern density within the phase plate, the local effective refractive index is varied, thus also changing the local propagation constant in the azimuthal direction. The OAM of any topological charge can be created by simply varying the thickness of the phase plate. The phase plate with topological charge (m=1) is 3D printed and the amplitude and the phase of the terahertz signal after passing the plate is characterized using the THz-time domain imaging system. Finally, we present the experimental setup and theoretical simulation on the multiplexing and de-multiplexing of several different OAM states for applications in wireless terahertz communication.