A 1040 GHz broadband subharmonic monolithic mixer in 0.18 μ m CMOS technology

A 1040 GHz broadband subharmonic monolithic passive mixer using the standard 0.18 μ m CMOS process is demonstrated. The proposed mixer is composed of a two-stage Wilkinson power combiner, a short stub and a low-pass filter. Likewise, the mixer utilizes a pair of anti-parallel gate-drain-connected diodes to achieve subharmonic mixing mechanism. The two-stage Wilkinson power combiner is used to excite a radio frequency (RF) and local oscillation (LO) signals into diodes and to perform broadband operation. The low-pass filter supports an IF frequency range from dc to 2.5 GHz. This proposed configuration leads to a die size of less than 1.1× 0.67 mm2. The measured results demonstrate a conversion loss of 15.617.6 dB, an LO-to-RF isolation better than 12 dB, a high 2LO-to-RF isolation of 5159 dB over 1040 GHz RF bandwidth, and a 1 dB compression power of 8 dBm.