A Novel 128 GHz 8-PSK Receiver Using an On-Chip Multi-Probed Interferometer for Direct Phase-to-Bits Demodulation

This work introduces a novel D-band receiver that enables direct phase-to-bits demodulation using an on-chip interferometer to bypass the traditional mixers and high-speed ADCs. The proposed architecture forms a standing wave on a λ/2 digitally-probed artificial dielectric transmission line (DiPAD-TL) by interfering with the incoming RF signal with a constant-phase reference LO signal. A 64-element power detector array and subsequent mixed-signal blocks along the DiPAD-TL are used to sample and identify the standing wave’s peak for mapping the RF phases dynamically to the baseband symbols. An amplitude tracking loop ensures balanced LO/RF power to minimize traveling waves and to ensure demodulation accuracy. The prototype receiver in 16nm FinFET performs direct 1.5 Gb/s 8-PSK demodulation at 128 GHz frequency with 134 mW DC power.