Mixing was realized in a four-terminal MOS transistor by applying radio-frequency and local oscillator (LO) signals to the front and back gates of the device. A mixer core so designed in a 0.5 /spl mu/m CMOS process is able to operate with 1 V supply and less than 0.2 mW of power while having a conversion gain up to 10 GHz using 0 dBm LO. Measured results include: 6 dB gain, 9.6 dB noise figure, 10 dBm IIP3 at 2 GHz and 6 dB gain, 18 dB noise figure, and -2 dBm IIP3 at 7 GHz.