A 0.18μm CMOS high linearity flat conversion gain down-conversion mixer for UWB receiver

A high linearity flat conversion gain down-conversion mixer for 3.1∼4.9GHz Ultra-wide Band (UWB) receiver is presented in this paper. The mixer is designed based on Gilbert cell. It adopts source degeneration resistors and current injection method to improve the linearity. Shunt-peaking technique and tuning inductors are used to flat conversion gain. Designed and fabricated with SMIC 0.18μm CMOS technology, the mixer achieves high linearity with third-order intercept point (IIP3) of better than 12.4 dBm, flat conversion gain of 4.9±0.2dB, while consuming only 5.1 mA from a 1.8V power supply. The core area is 920×840 μm
²
.