In this article, a 7‐GHz to 40‐GHz ultra‐wideband passive double‐balanced mixer MMIC using compact wideband Marchand balun (CWMB) is presented. The CWMB is analyzed and designed by introducing a novel optimal impedance deviation coefficient. A trade‐off between the needed bandwidth and the acceptable insertion loss in an ultra‐wideband passive‐doubly‐balanced mixer design can be made through introducing the optimal impedance deviation coefficient. Finally, to verify the proposed methodology, a compact wideband passive double‐balanced mixer monolithic microwave integrated circuit (MMIC) was designed and fabricated using a standard gallium arsenide (GaAs) pHEMT technology according to the process characteristics. Experimental results show that an ultra‐wideband mixer MMIC is realized from 7 GHz to 40 GHz (140% fractional bandwidth) with a measured conversion loss between 9.5 dB~12.5 dB (in‐band fluctuation less than 3 dB) and a LO‐to‐RF isolation larger than 34 dB. The measurement results are in good agreement with the simulation results.

中文翻译：

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基于最佳阻抗偏差系数的7至40 GHz片上混频器的系统设计

本文介绍了一种使用紧凑型宽带Marchand balun（CWMB）的7 GHz至40 GHz超宽带无源双平衡混频器MMIC。通过引入新颖的最佳阻抗偏差系数来分析和设计CWMB。通过引入最佳阻抗偏差系数，可以在超宽带无源双平衡混频器设计中在所需带宽和可接受的插入损耗之间进行权衡。最后，为了验证所提出的方法，根据工艺特性，使用标准砷化镓（GaAs）pHEMT技术设计并制造了紧凑的宽带无源双平衡混频器单片微波集成电路（MMIC）。实验结果表明，超宽带混频器MMIC在7 GHz至40 GHz（140％的分数带宽）范围内实现，测得的转换损耗介于9.5 dB〜12.5 dB（带内波动小于3 dB）和LO至‐RF隔离大于34 dB。测量结果与仿真结果吻合良好。