In this paper, an UWB down-conversion mixer is presented with high 3rd order linearity. The UWB bandwidth of the mixer can be achieved in 0.9–5 ​GHz by using a cascode structure with four capacitors. These capacitors are used to make a feedback network for IM3 cancellation in transconductance stage of active double-balanced Gilbert mixer cell. By using this novel technique, a maximum IIP3 of 20.5 dBm is obtained in IF frequency of 1 ​MHz and this mixer can be applied for direct conversion receivers (DCRs). Furthermore, the proposed mixer can work up to IF frequency of 100 ​MHz for low-IF applications. The conversion gain is about 11.3 ​± ​0.5 ​dB with 16.9 ​dB NF in IF frequency of 1 ​MHz. The power consumption is 3.5 ​mW from a 1.2 ​V power supply. The schematic of the designed mixer is simulated in 65 ​nm RF TSMC CMOS technology with Cadence IC Design tools and also was analyzed and compared with Volterra series for more accuracy. The dimensions of the mixer’s layout are roughly $391\mu m\times 132\mu m$.

本文提出了一种具有高三阶线性度的UWB下变频混频器。通过使用具有四个电容器的共源共栅结构，混频器的UWB带宽可以在0.9-5 GHz范围内实现。这些电容器用于在有源双平衡吉尔伯特混频器单元的跨导阶段为IM3抵消建立反馈网络。通过使用这种新颖的技术，在1 MHz的IF频率下可获得20.5 dBm的最大IIP3，并且该混频器可以应用于直接转换接收器（DCR）。此外，对于低中频应用，建议的混频器可以在高达100MHz的中频频率下工作。在1 MHz的IF频率下，转换增益约为11.3±0.5 dB，NF为16.9 dB。1.2 V电源的功耗为3.5 mW。设计的混频器的原理图使用Cadence IC设计工具在65纳米RF TSMC CMOS技术中进行了仿真，并进行了分析并与Volterra系列进行了比较以提高准确性。调音台布局的尺寸大致为$391\mu 米\times 132\mu 米$。