A BROADBAND HIGH LINEARITY CURRENT-REUSE BULK-CONTROLLED MIXER FOR 4G APPLICATIONS

A high linearity down-conversion mixer for the application of the fourth generation (4G) mobile communication systems is presented. The presented 2.3 to 5.8 GHz broadband mixer adopts current-reused and bulk-controlled techniques. The linearized transconductor stage is composed of the CMOS amplifiers and the bulk-controlled compensation (BCC) transistors. The bulk-controlled voltage is applied to adjust the threshold voltage of the BCC transistor. Thus, the equivalent third-order intermodulation (IM3) term of the CMOS amplifiers and the BCC transistors can be mitigated so as to improve the linearity. Furthermore, the current-reused architecture enhances the conversion gain of the proposed mixer and compensates the loss caused by the shunt feedback matching network. The presented mixer consumes 4.8 mA from a 1.5 V power supply. The measurement results of the mixer exhibit the maximum power conversion gain of 11.3 dB. The input third-order intercept point (IIP3) of 4.7 dBm over the entire 2.3-5.8 GHz band is observed.