This paper presents a new Post Distortion Cancellation (PDC) Gilbert-mixer for Ku-band applications to minimize the thirdorder nonlinear current of transconductance transistors. To illustrate the effectiveness of this scheme, distortion analysis using Volterra series is given. An extra inductor is added between source nodes of switching transistors to decrease the deteriorating effect of parasitic capacitances. The proposed mixer has been simulated in a 0.18-µm RF-CMOS technology and consumes only 6-mW from a 1.8-V supply. Compared to conventional Gilbert-mixer, it typically improves IIP3 by 4.2 dB, power conversion gain by 1.1 dB and noise figure by 1.4 dB. Keywords: Post Distortion Cancellation technique, Ku-band, CMOS, common-gate Gilbert-mixer Classification: Integrated circuits References[1] B. Gilbert, "A precise four quadrant multiplier with subnanosecond response," IEEE J. Solid-State Circuits, vol. 3, no. 4, pp. 365-373, Dec. 1968 Lett., vol. 16, no. 4, pp. 182-184, April 2006. [7] N. Kim, V. Aparin, K. Barnett, and C. Persico, "A cellular-band CDMA 0.25 µm CMOS LNA linearized using active post-distortion," IEEE J.

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This letter presents a new architecture of merged low noise amplifier and mixer, which employs a noise cancellation scheme and uses an inductor as an inter-stage matching network between LNA and mixer to absorb parasitic capacitances. As the parasitic capacitances degrade the gain and noise figure of the entire circuit, using an inductor in the inter-stage can very effectively improve both noise figure and gain of the circuit. Based on this new method, a merged LNA-mixer has been designed in a 0.18-μm RF CMOS technology. Simulation results show 4-dB increase in power conversion gain and 1.7-dB improvement in noise figure in comparison with the case without inter-stage filter. This circuit draws only 5 mA from a 1.8 V supply and covers the frequency range of 1.3 GHz to 4.1 GHz. Its large bandwidth as well as low power consumption makes it suitable for rapidly growing software defined radio RF transceivers.