A Bidirectional 56-72 GHz to 10.56 GHz Tranceiver Front-End with Integrated T/R Switches in 28-nm CMOS Technology

This paper presents a co-matched bidirectional 56-72 GHz to 10.56 GHz transceiver (TRX) front-end (FE) targeting the IEEE 802.11ad/ay standard with integrated transformer-based transmit/receive (T/R) switches. The TRX FE includes an RF FE and an IF FE. In the RF FE, the reused transformer functions as T/R switch, balun, and impedance matching networks for both LNA and PA simultaneously. The T/R switch, LNA and PA are co-matched, bandwidth and linearity enhancement techniques are utilized in the LNA and PA's inter-stage matching networks. A similar design method is also used in the IF FE. The proposed architecture is implemented in a 28-nm CMOS technology; test results prove that the insertion loss of the proposed T/R switches introduced in RF/IF FE is about 1.2 dB. It also benefits from the gain-boosting technique in RX mixer, the RX mode of the TRX FE achieves maximum conversion gain (CG) of 23.8 dB over 56-72 GHz while demonstrating a 6.1 dB minimum noise figure. The TX mode of the TRX FE achieves maximum CG of 26.2 dB over 56-72 GHz while demonstrating an 8.5 dB maximum OP1dB. The core area of the TRX FE is only 1.2 mm × 1.2 mm.