DOI: 10.1109/TMTT.2025.3616028   IEEEXplore: https://ieeexplore.ieee.org/document/11197152

Multifunctional filtering circulator in a single structure based on spatiotemporal modulation (STM) with tunable frequency, phase, and self-interference cancellation (SIC)

1.2 GHz for this proof of concept

A 170° phase tuning range is achieved via phase control networks (PCNs) at the Tx and Rx ports, maintaining constant amplitude for Tx–antenna (Ant) and Rx–Ant channels. Secondary Tx–Ant–Rx leakage is exploited to cancel direct Tx–Rx leakage using an adjustable reflection coefficient network at the Ant port, achieving up to 60-dB isolation. With the proposed structure, phase tuning and SIC can operate simultaneously.

Full duplex beamforming for Internet of Things (IoT), telecommunications, satellite communications, and integrated sensing and communication systems applications.

4.3 - 6.2 dB insertion loss; 60 dB isolation; 150° phase shifting range (stand-alone). 4.3 - 5.9 dB insertion loss, 50 dB isolation, 150° phase shifting range when incorporated into a proof of concept 1x4 filtering full-duplex beamforming network with independent -11° to 16° Tx scanning range and -13° to 16° Rx scanning range.