Generation of an Orbital-Angular-Momentum-Mode-Reconfigurable Beam by a Broadband 1-Bit Electronically Reconfigurable Transmitarray

Broadband orbital-angular-momentum (OAM) multiplexing is of great interest due to its ability to increase channel capacity in wireless communications. However, broadband OAM-mode-reconfigurable transmitarrays have yet to be developed. Here, a broadband 1-bit electronically reconfigurable transmitarray for OAM-mode-reconfigurable beam generation is proposed, fabricated, and tested. The OAM transmitarray includes 20 ? 20 elements with a 1-bit phase resolution, each element is controlled by two p-i-n diodes with a minimum insertion loss of 0.9 dB and a 3-dB transmission bandwidth of 17.1%. A nearly perfect 1-bit phase resolution is obtained by reversing the current. The OAM mode can be switched between l = +1 and l = +2 based on a steering-logic board. Both simulation and experiment results show the transmitarray can generate a broadband OAM-mode-reconfigurable beam from 9.5 to 10.5 GHz. The proposed transmitarray may have potential applications in broadband OAM-multiplexing communications.

Automated summary

Broadband orbital-angular-momentum (OAM) multiplexing is being explored for its potential to increase channel capacity in wireless communications. A broadband 1-bit electronically reconfigurable transmitarray for OAM-mode-reconfigurable beam generation has been proposed, fabricated, and tested, showing potential applications in broadband OAM-multiplexing communications.