A Bidirectional 28 GHz RF Transceiver Front-End with Test and Calibration Interface for 5G Phased Arrays

This paper presents a bidirectional 28 GHz RF transceiver (TRX) front-end for 5G that provides interfaces for calibration and angle of arrival (AoA) estimation by adding area-optimized broadband 10 dB broadside couplers. In addition, possible deployment scenarios and corresponding architectures in large arrays are described. The front-end integration level includes a receive (RX) chain, a transmit (TX) chain and a serial peripheral interface (SPI) for digital reconfigurability. Fabricated in a 130 nm SiGe BiCMOS technology, it delivers up to 22.6 dB and 22.5 dB gain for RX and TX modes, respectively, and offers measured control ranges of 9.1 dB / 9.2 dB for amplitude and 360° for phase. An input-referred 1 dB-compression point (P
1 dB
) of -24.3 dBm and an output-referred P
1 dB
of 3.0 dBm is achieved with a DC power consumption of 227.8 mW and 212.2 mW for RX and TX, respectively.