Interference-Resilient Communication With a 28 GHz Transceiver Utilizing OAM Waves

This article presents a custom-made SiGe-based transceiver at millimeter-wave frequencies capable of the generation and detection of radio waves with helical phase distribution called orbital angular momentum (OAM). The proposed architecture is able to suppress the in-band interference at the front-end that otherwise cannot be filtered by front-end filters. The transmitter and receiver chip integrates a front-end power amplifier (PA), phase shifter, low-noise amplifier (LNA), and front-end switches to switch the amplifiers ON and OFF to generate OAM modes. A 4-element transceiver array was constructed using custom-designed chips, mounted on a PCB with a custom-designed circular antenna array. The design generates $l=0$, (+1) and (−1) OAM modes simultaneously, where the mode ($l=0$) is a plane wave mode. Since each mode carries the same information, it is shown that if an interfering signal disrupts the plane wave mode ($l$ = 0), the information can still be recovered from the OAM mode ($l$ = +1), where the interferer is suppressed due to a particular detection method of the OAM wave at the receiver. The experiments show 19 dB interference suppression near the operating frequency of the OAM mode.