A CMOS 0.5-2.5GHz Full-Duplex MIMO Receiver with Self-Adaptive and Power-Scalable RF/Analog Wideband Interference Cancellation

A 65nm CMOS 0.5-2.5GHz full-duplex (FD) MIMO receiver (RX) with self-adaptive ≥24dB RF/analog interference cancellation across 20MHz BW is presented. An LMS adaptive circuitry is co-designed with and partially embedded in a wideband RF/analog interference canceller and a gain-boosted mixer-first RX. With the adaptive circuitry fully integrated and consuming 14mW, the cancellers adapt themselves to an unknown channel in 1μs. The FD MIMO RX is also power-scalable - when used as a digital beamformer, the NF-power scalability of the FD RX enables a nearly constant canceller DC power per element, despite a quadratic increase of cancellers.