A 94 GHz up-conversion mixer using standard 90 nm CMOS technology is reported. The components of this mixer include an enhanced double-balanced Gilbert cell with PMOS negative resistance compensation (NRC) for conversion gain (CG) enhancement and modified derivative superposition (DS) in the transconductance (GM) stage for linearity improvement, a Marchand balun for converting the single LO input signal to differential signal, another Marchand balun for converting the differential RF output signal to single signal, and an output buffer amplifier for loading effect suppression, CG enhancement and power consumption reduction. The mixer consumes low power of 8.5 mW and achieves excellent LO-port input reflection coefficient better than -10 dB for frequencies of 81.4~110 GHz, and RF-port input reflection coefficient better than -10 dB for frequencies of 33.8~105.5 GHz, i.e. the input matching bandwidth is 71.7 GHz. The mixer achieves maximal CG of 3.6 dB at 97 GHz, and CG of 2.1±1.5 dB for frequencies of 77.5~100.2 GHz. That is, the corresponding 3 dB CG bandwidth is 22.7 GHz. In addition, the mixer achieves LO-RF isolation of 41.3 dB at 94 GHz. To the authors' knowledge, the CG, LO-RF isolation, power dissipation and matching bandwidth results are one of the best data ever reported for a W-band (75~110 GHz) up-conversion mixer.