A Complementary Ring Mixer Driven by a Single-Ended LO in 22-nm FD-SOI CMOS for K and Ka-Bands

This article presents a double-balanced up-conversion ring mixer based on complementary switches operating at millimeter-wave frequencies. Complementary-switching relieves the mixer from the need for a differential Local-Oscillator (LO) signal, simplifying the design and improving the circuit performance. A prototype, capable of operation between 18 GHz and 32 GHz, is implemented in a 22 nm FD-SOI CMOS technology offering n- and p-type transistors with comparable performance. Furthermore, the presented circuit also exploits the back-gate control voltage offered by the process to minimize the transistors threshold voltage, reducing the minimum LO power required to saturate the mixer gain. Measurements showed a conversion gain of -5.5 dB, an output power at 1 dB gain compression (o1dBCp) of -7 dBm, and a Radio-Frequency (RF) bandwidth of 10 GHz. These results were demonstrated for an LO power of 3 dBm at 23.5 GHz or 28 GHz, a DC power of 2.2mW, and all the mixer ports matched to 50$\Omega $ . The active area of the chip is 0.11mm
²
, the smallest so far demonstrated for ring mixers. These performances translate in the best-reported figure of merit, which relates gain, RF up-converted power, and required DC and LO power.