A 39-GHz Up- and Down-Conversion Mixer System in 65-nm CMOS for 5G Communication

This paper presents a 39-GHz up- and downconversion mixer system in 65-nm CMOS for 5G mmWave communication. To achieve high conversion gain and low LO leakage, the active Gilbert cell is adopted for both upconversion and down-conversion mixer. To address high isolation and low insertion loss, a pi-type impedance matching network and a series-shunt structure are introduced for LO/RF and IF switches, respectively. In addition, capacitive neutralized differential IF and RF buffers are introduced to enhance the power gain and output linearity of the up- and down-conversion mixer, respectively. Fabricated in a 65-nm CMOS process, the up- and down-conversion mixer system realizes a measured conversion gain of 1± 1.5dB and 3.5± 1.5dB from 34.7 to 41.2 GHz and 32 to 42.3 GHz, respectively. At the maximum conversion gain, the up-conversion mixer achieves an output 1-dB gain compression point (OPldB) 2.5 dBm. From 34 to 41.5 GHz, the down-conversion mixer achieves a third-order output intercept point (OIP3) from 8.4 to 9dBm.