A high gain flatness high linearity down conversion mixer for Ku band application

A high linearity down-conversion mixer for 12-18GHz Ku band application is presented in this paper. The proposed mixer based on Gilbert cell obtains high gain flatness. Bias current decoupling technique is adopted to suppress noise at the output. Current-injection circuit and resonating inductors at the source of switching stage are added to improve the gain flatness and linearity. The proposed mixer is simulated with TSMC 0.18μm 1P6M CMOS process. The conversion gain of 7.32±0.8dB is achieved over the entire bandwidth. The minimum double-sideband noise figure is 17.26dB. The maximum input third-order intercept point (IIP3) is 3.5dBm at 14.5GHz. The power consumption is 6.36mW at 1.2V supply voltage. The chip size including pads for further measurement is 0.9×0.983mm².