Low-Loss Broadband Magnetless Circulators for Full-Duplex Radios

In this paper, we present a differential magnetless circulator based on spatiotemporal modulation of bandpass wye junctions. We provide measured results for all relevant metrics, including S-parameters, harmonic response, power handling, linearity, and noise figure, showing remarkable performance compared to current state of the art. Furthermore, we propose a technique to increase the 20 dB isolation bandwidth of these circulators to over 12% of the RF center frequency by combining them with passive bandpass filter technology.