A High Linearity Up-Conversion Mixer for LTE MTC Applications

The paper presents an up-conversion mixer fabricated in standard TSMC 1P9M65nm CMOS process to meet the requirements for LTE MTC communications. The present mixer is designed for IF frequency of lOMHz, LO frequency of 1.9 GHz with a supply voltage of 1.2 V. A folded structure and resistive source feedback are employed to improve the linearity without consuming excessive voltage headroom. Filter capacitors are added to the drain of the transconductance stage to alleviate the feedthrough from LO port to IF port. The mixer achieves a conversion gain of 1.46 dB, an output thirdorder intercept of17.7 dBm and a LO-RF isolation of -230dB.