A 1.7?2.1GHz +23dBm TX power compatible blocker tolerant FDD receiver with integrated duplexer in 28nm CMOS

The first integrated duplexer compatible with a -15dBm RX blocker for up to 23dBm TX power is reported. A three winding transformer is driven at the primary by a single ended PA and drives a differential push-pull common-gate LNA. Only 45 dB isolation is required thanks to the 23 dBm RX IIP3 drastically simplifying hybrid balancing and adaptation loop. Cascaded noise figure of duplexer, LNA and base-band stays below 6.7dB and the TX insertion loss below 4 dB from 1.6 to 2.2 GHz. The chip is implemented in 28nm CMOS has an active area of 0.7mm² and uses only 26mW.