基于GaAs pHEMT工艺的Ka频段双通道开关滤波器芯片

A Ka-band Two Channel Switchable Filter MMIC Using GaAs pHEMT Process

传统的毫米波开关滤波器组件通常基于分立器件或分立芯片,已无法满足快速发展的毫米波频段通信系统特别是5G通信系统的小型化、轻量化需求。为此,文中采用0.25μm GaAs pHEMT工艺,设计并实现了一款工作在Ka频段的双通道开关滤波器芯片。芯片内部集成了单刀双掷开关和梳状线型带通滤波器,相较于只使用ADS软件设计整个芯片,通过使用HFSS软件建立了更为准确的芯片衬底模型,并使用该模型对滤波器电路进行设计,提高了滤波器电路的仿真精度。最终,开关滤波器芯片的尺寸为3.3mm×2.6mm,测试结果显示:该芯片两个通道在通带内的插入损耗小于7dB,带内回波损耗优于15 dB,典型带外抑制优于35 dB,测试结果与仿真结果吻合较好。

Traditional millimeter wave switchable filter components are usually designed with discrete components or discrete chips,and it can no longer meet the needs of miniaturization and lightweight of the millimeter wave communication systems,especially the 5 G communication system.So a Ka-band dual channel switchable filter MMIC has been designed using 0.25μm GaAs pHEMT process.The SPDT and the band-pass filter are integrated in this chip.Compared to design the whole chip by the software of ADS,a more accurate substrate of the chip is modeled and used to design the filter circuits by the software of HFSS,so the accuracy of the simulations of the filter circuits can be improved.The final size of the chip is 3.3 mm×2.6 mm.The test results show that:the insertion loss is less than 7 dB in the pass-band,the return loss is better than 15 dB in the pass-band,the typical out-of-band rejection is better than 35 dB,and the test results are in good agreement with the simulation results.