Willner group and WiDeS collaborate to achieve mm-wave OAM multiplexing, present results in Nature Communications
Orbital angular momentum (OAM) describes a helical phase “twist” of electromagnetic waves as they propagate. There exists a set of twisting OAM beams that are orthogonal so that multiple beams can propagate along the same axis. This enables efficient multiplexing and demultiplexing of multiple independent data-streams in line-of-sight situations, increasing the total capacity over the same physical medium. In an experiment designed and supervised by Alan Willner (head of the optical communications group) and Andy Molisch from WiDeS, a group of USC researchers and visiting scientists demonstrated such an OAM-based multiplexing system at millimeter-wave frequencies. They transmitted 32 Gbit/s data rate, using 4 OAM modes (each with two polarizations). The results, first presented at ICC in Sydney, were published in September in Nature Communciations, and drew large attention.