A 26.5-to-29.5GHz Transformer-Based Doherty Phased-Array Transceiver Front-End With 7-Bit Phase Shifter and 16% Back-Off Drain Efficiency

Millimeter-wave (mm-wave) phased-array transceivers (TRXs) with beamforming techniques are extensively utilized in 5G wireless communication systems to mitigate significant free space path loss. However, as the scale of the phased array and data rate increases, it encounters two major challenges. Firstly, the phase shifting scan range and resolution must meet the requirements of beam steering resolution [1, 2]. Secondly, the system efficiency, particularly in the power back-off (PBO) efficiency, needs to be improved due to the high peak-to-average power ratio (PAPR) of the quadrature amplitude modulation (QAM) signals.