An innovative mixer architecture using gate- and drain-pumped with combining drain terminals of nMOS transistors is proposed to enhance IF and local oscillator (LO) operation bandwidths in 90-nm CMOS for astronomical application. With 0.6 mW of dc power, this mixer achieved peak conversion gains of −6.2, −6.1, −8.6, and −7.2 dB at LO frequencies of 30, 50, 60, and 90 GHz, respectively. At an LO power of 2.3 dBm and an LO frequency of 30 GHz, the IF 3-dB bandwidth is 26 GHz. When the LO power is 4.2 dBm at an LO frequency of 90 GHz, the mixer has an IF 3-dB bandwidth of 16 GHz. The IP 1dB (input 1-dB gain compression) is better than 2 dBm from 30 to 90 GHz. The chip occupies an area of 0.389 mm2. Compared with other published works, this mixer demonstrates a breakthrough for extremely wide IF and LO bandwidths in low dc power consumption with high IP 1dB.