An 8 - 10 GHz linearised single-sideband Gilbert upconversion mixer is demonstrated in silicon BiCMOS technology. The QuBiC4X 0.25 μm BiCMOS process of NXP has been used. The device has an integrated local oscillator driver with polyphase quadrature generation. The IF chain uses feedback, selectable gain settings and DC offset circuitry to be compatible with more than one type of direct digital synthesizer and to minimize spurious products that are not cancelled by the mixer concept. The device has sideband suppression of over 45 dB and third-order spurious suppression of over 40 dB.