A 3-5 GHz low power UWB mixer using tunable active inductors

This paper presents the design of a low power up conversion double balanced Gilbert cell mixer using 0.18 μm CMOS technology. The proposed circuit uses a dynamic current bleeding technique made of a single transistor and two active inductors to resonate the tail capacitances at the LO switches so to increase the conversion gain and decrease the noise figure. It also adopts a post distortion cancellation technique made of two auxiliary transistors that linearize the input current and absorb the third order intermodulation distortion which considerably improve the linearity of the circuit. Performed simulations showed a conversion gain of 13.31 dB at the central frequency of the UWB (3-5GHz) third channel, a minimum noise figure of 8.6 dB and an IIP3 that reached 4.2 dBm. The circuit consumes a low power of about 5.2 mW from a 1.8V dc supply voltage and corner simulations showed that the process variations have small effect on the proposed circuit’s performance.