An Innovative Joint-Injection Mixer With Broadband If and RF for Advanced Heterodyne Receivers of Millimeter-Wave Astronomy

An innovative mixing unit of the proposed mixer named joint-injection-mixer (JIM) features both wide IF and RF bandwidths (BWs) for next-generation advanced heterodyne receivers of millimeter-wave astronomy. This proposed mixer demonstrates an RF frequency range from 60 to 148 GHz and an IF frequency range from dc to 36 GHz. The dc power consumption of the JIM mixer is 2 mW with LO driving power of 0 dBm. All the measured results are under 0-dBm LO power. The conversion gain (CG) of the JIM mixer is from -8 to -14 dB. The JIM mixer in this work is implemented for fundamental mixing as downconversion. By utilizing the proposed modified Marchand balun with ultrabroad BW, the LO-to-RF isolation of the JIM mixer achieves better than 40 dB from 60 to 140 GHz. The fabricated process for the JIM mixer is the 40-nm CMOS process. The chip sizes, excluding and including pads, are 0.144 and 0.22 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , respectively. The proposed JIM mixer features the state-of-the-art mixer with the widest IF BW compared with all the prior works. Compared with the present capability of world-leading receivers for radio astronomy, the 36-GHz IF BW of the mixer in this work can construct a next-generation receiver for astronomy to provide received data rate by at least three times.