A Broadband Zero-IF Down-Conversion Mixer in 130 nm SiGe BiCMOS for Beyond 5G Communication Systems in D-Band

This brief presents a broadband D-band down-conversion mixer in a cost efficient 130nm SiGe BiCMOS technology with a f
_t
/f
_max
of 250/370GHz from Infineon Technologies AG. The proposed mixer covers the entire D-band with a 32dB peak conversion gain and a 3dB bandwidth of 35GHz at a measured noise figure between 9.5 and 12dB in the specified band while consuming only 65mW DC power. To achieve large RF and IF bandwidths and a low noise figure, the mixer design is based on a low-biased switching quad, which is loaded with a modified Cherry-Hooper transimpedance amplifier. The results, which are verified by measurements, are based on a detailed analysis of the transistor characteristics, broadband matching networks and an appropriate layout parasitic extraction. All interfaces to the circuit are designed single-ended for a dense chip-to-package transition. For this purpose, high performance Marchand baluns are used at RF- and LO-port, respectively. With a moderate noise figure and a low power consumption, the presented circuit meets the requirements for beyond 5G systems.