一种基于GaAs pHEMT工艺的18~40 GHz六位高精度数控移相器

A 18⁃40 GHz 6⁃bit High⁃precision Phase Shifter MMIC Using GaAs HEMT Technology

基于0.15μm GaAs pHEMT工艺研制了一款工作频率为18~40 GHz的高精度六位数控移相器芯片。其中5.625°、11.25°和22.5°移相位采用了改进型的串并联电容移相结构,该结构可通过增加串联电感改善移相精度;45°和90°移相位采用了磁耦合全通网络型移相结构;180°移相位使用了基于串并联谐振结构的改进型移相器电路,拓展了移相器带宽,提高了移相精度。移相器芯片的实际加工面积为2.8 mm×1.4 mm。芯片的测试结果表明,在18~40 GHz频率范围内,移相精度均方根误差小于2.3°,移相寄生调幅均方根误差小于0.7 dB,全态损耗小于13.5 dB,全态输入、输出驻波分别小于1.7、1.9。

Based on 0.15μm GaAs pHEMT technology,a 6-bit high-precision numerical control phase shifter monolithic microwave integrated circuit with working frequency of 18 to 40 GHz was pro⁃posed.An improved phase shifter circuit with series and parallel capacitors was utilized in the 5.625°,11.25°and 22.5°phase bits,which could improve phase shifting accuracy by adding series inductors in⁃to the circuit.The magnetically coupled all-pass network was used in the 45°and 90°phase bit.In the 180°phase bit,a modified phase shifter based on the series and shunt resonators was employed to ex⁃tend the bandwidth and achieve higher phase shifting precision.The fabricated chip occupied the size of 2.8 mm×1.4 mm.The measurement results demonstrate that the root mean square value of phase errors is less than 2.3°,and the RMS value of amplitude error is less than 0.7 dB within the operating frequency of 18 to 40 GHz.The insertion loss is less than 13.5 dB among all phase states.The input and output VSWR are better than 1.7 and 1.9 among all phase states,respectively.