28 GHz CMOS可变增益双向有源移相器设计

Design of a 28 GHz variable gain bidirectional active phase shifter

基于65 nm CMOS工艺设计了一种可用于5G毫米波相控阵系统的可变增益双向有源移相器。该移相器采用二阶多相滤波器产生正交信号,利用矢量调制器实现移相和增益调节,利用开关切换信号传递方向。矢量调制器前级采用吉尔伯特单元对正交信号调幅实现360°移相,后级采用基于交叉耦合结构的可变增益放大器实现低附加相移的增益调节。后仿真结果表明,RMS相位误差小于-3.4°(TX)和-4.2°(RX),RMS增益误差均小于0.5 dB,增益调节范围为11.25 dB,产生的附加相位变化小于±3°(TX)和±1.6°(RX),移相模块的功耗为8.5 mW。

A variable gain bidirectional active phase shifter for 5G mm wave phased array systems is designed by the 65 nm CMOS technology.A second⁃order poly⁃phase filter is used to generate quadrature signals,and a vector modulator is designed to modulate them for phase modulation and gain adjustment.A Gilbert unit is deployed as the front stage of the vector modulator to realize the 360°phase shift by the amplitude modulation of the quadrature signal.And a variable gain amplifier is utilized as the latter one to modulate gains for the low additional phase shift.The post⁃simulation results show that the RMS phase error is less than-3.4°(TX)and-4.2°(RX),the RMS gain error is less than 0.5 dB,the gain adjustment range is 11.25 dB,the resulted additional phase variation is less than±3°(TX)and±1.6°(RX),and the power of the phase modulation module is 8.5 mW.