基于GaN HEMT的非对称型Doherty功率放大器设计  

Design of Asymmetric Doherty Power Amplifier Based on GaN HEMT

作　　者：汪荣昌 陈新宇 张吕 陈志勇 祝超 曾瑞峰 WANG Rongchang;CHEN Xinyu;ZHANG Lü;CHEN Zhiyong;ZHU Chao;ZENG Ruifeng(Nanjing University of Posts and Telecommunications,Nanjing,210023,CHN;Nanjing Guobo Electronic Company Limited,Nanjing,211100,CHN)

机构地区：[1]南京邮电大学,南京210023 [2]南京国博电子有限公司,南京211100

出　　处：《固体电子学研究与进展》2021年第5期343-347,358,共6页Research & Progress of SSE

摘　　要：采用SiC衬底0.45μm GaN HEMT工艺,设计了一款GaN混合集成两级非对称Doherty功放,在较大的回退状态下仍具有较高的效率。为了减小芯片尺寸,采用无源集总元件搭建功率分配器,同时采用π型结构替代1/4λ阻抗变换线。测试结果表明:在3.4~3.6 GHz的频率范围内,饱和功率达到45.2 dBm,饱和效率达到53.2%。输出功率回退8 dB时的效率达到40%,线性增益达到24 dB。以80 MHz带宽LTE信号作为输入,经过数字预失真(DPD)技术优化后的邻信道功率比(ACPR)为-50.8 dBc。电路尺寸为10 mm×6 mm。A GaN hybrid microwave integrated circuit power amplifier with two-level asymmetric Doherty was designed by exploiting 0.45μm GaN HEMT technology on SiC substrate,which had a higher collector efficiency under a larger power back-off state.The circuit was miniaturized by using passive lumped components to build the power divider,and quarter-wave impedance transformer could be fully integrated usingπ-type structure.The test results show that the saturated output reaches 45.2 dBm and saturated drain efficiency reaches 53.2%in the frequency range from 3.4 GHz to 3.6 GHz.When the power is backed off by 8 dB,the drain efficiency is 53.2%,and the power gain is 24 dB.The ACPR which optimized by the DPD technology is-50.8 dBc when driven by 80 MHz LTE signal.The size of the circuit is 10 mm×6 mm.

关 键 词：氮化镓高电子迁移率晶体管 DOHERTY功放 小型化 数字预失真 

分 类 号：TN722.5[电子电信—电路与系统]