A mm-Wave Wideband Tunable Electrical Balance Duplexer with an Integrated Low-Noise Amplifier in 22-nm CMOS FDSOI

This paper introduces an integrated electrical balance duplexer (EBD) combined with a low-noise amplifier (LNA), operating within 23–30 GHz suitable for mm-Wave full-duplex (FD) applications. The duplexer provides 40 dB TX-to-RX isolation over >300 MHz bandwidth and is equipped with a tunable balancing network to maintain the balance condition across the operating frequency range. The balancing network employs stacked switches, ensuring sufficient linearity and power handling. Additionally, the balancing network accommodates an antenna VSWR of up to 1.22:1. The LNA, integrated with the RX port of the duplexer, draws 40 mA from a 1.2 V supply and demonstrates measured performance metrics, including an IIP3 of -7 dBm, an OP1dBof -5 dBm, and a voltage gain ranging from 19 to 20 dB. The RX path, encompassing the EBD's RX path loss and LNA gain, achieves a noise figure (NF) of less than 8.5 dB. The chip is fabricated by GlobalFoundries' 22-nm CMOS FDSOI and occupies an area of 1.86 mm×1.02 mm including DC and RF probing pads.