A Transformer-Based Up-Conversion Mixer With Wide IF Bandwidth for Multi-Beam 5G New Radio

This letter presents a wideband millimeter-wave (mm-Wave) up-conversion mixer with high linearity for multibeam 5G new radio. It consists of a double-balanced switch stage designed by a ring topology and a separated gain stage realized by the common-source (CS) structure with crosscoupled capacitors. To improve the linearity of the circuit, the passive switch stage is placed before the gain stage. Transformer-based high-order matching networks for the mixer are also developed to broaden the RF, LO, and IF terminals' impedance matching. The measured results show the mixer achieves an output 1-dB compression point (OP1dB) of 2.48 dBm with a conversion gain of 2.5 dB. Thanks to the transformerbased matching networks, the fractional matching bandwidths of IF, LO, and RF are up to 88%, 47.6%, and 26.4%, respectively.