40 M Transmission of OAM Mode and Polarization Multiplexing in E-Band

Abstract

This paper presents the development of prototype radio equipment for orbital angular momentum (OAM) mode and polarization multiplexing transmission in E-band, as well as the results of a field trial using the prototype. The equipment consists of a radio frequency unit (RF UNIT) and a base-band unit (BB UNIT). The RF UNIT has a uniform circular array with eight elements and E-band frequency converters for each element. The BB UNIT for the transmitter has OAM mode multiplexers and digital modulators, and one of the receivers has an adaptive OAM mode de-multiplexer and digital demodulators which can operate in real-time. Sixteen multiplexing transmissions (eight OAM modes and two polarizations) over a link distance of 40 m with 256 QAM and spectral efficiency of 85.7 bps/Hz have been achieved.