NTT has realized OAM (Orbital Angular Momentum) multiplex transmission using an ultra-wide bandwidth of 32 GHz. The world’s first successful high-capacity wireless transmission of 1.44 terabits/second.
This achievement was realized using the sub-terahertz band from 135 GHz to 170 GHz, and NTT aims to realize IOWN (Innovative Optical and Radio Communication) as an innovative wireless communication technology that enables wireless access to vast amounts of information exceeding 1 terabit/second. Wireless Network) concept, which expands the high-capacity communication network and information processing infrastructure centered on light to wireless networks including 6G.
By developing this technology, various future services are expected, including VR/AR, high-definition video transmission, connected cars, and telemedicine.
NTT takes the approach of increasing the spatial multiplexing number by multiplexing a plurality of OAM waves using an analog circuit called Butler Matrix (“Butler circuit”). This approach can reduce the enormous amount of digital signal processing required to eliminate interference between radio waves corresponding to different spiral structures in high-capacity communications exceeding 1 terabit.
NTT succeeded in developing an antenna-integrated Butler circuit. This circuit is designed to simultaneously generate and separate eight different OAM waves over a very wide band from 135 GHz to 170 GHz, which can be used to multiplex and transmit eight data signals. .