A 160 MHz bandwidth 90° active RC–CR phase shifter with integrated on-line amplitude locked loop (ALL) calibration targeted to 802.11ac 5 GHz wireless local area network (WLAN) applications is presented in this paper. The quadrature phase shifter is a key component for transceivers employing the Hartley image rejection architecture. The passive RC–CR phase shifter generates the required two quadrature outputs with an accurate 90° phase shift over the required bandwidth but lack the required accuracy in amplitude matching. A 90 nm CMOS microelectronic implementation of an RC–CR phase shifter is proposed with active resistors that are adjusted by an integrated on-line ALL calibration system to maintain matching amplitudes of the quadrature outputs over the required bandwidth. The on-line ALL calibration system employs peak detectors, comparators, digital logic control, and charge pump to incrementally adjust the active resistors while converging to matched amplitudes similar to the operation of phase-locked loop with a phase-frequency detector and charge pump. The resulting 90 nm implementation supports − 40db to − 70db image rejection ratios (IMMRs) over the IF 170 MHz to 330 MHz bandwidth. The 90 nm CMOS implementation is fully functional considering process variations based on 200 Monte Carlo simulations.

本文介绍了一种 160 MHz 带宽 90° 有源 RC-CR 移相器，该移相器具有针对 802.11ac 5 GHz 无线局域网 (WLAN) 应用的集成在线锁相环 (ALL) 校准。正交移相器是采用 Hartley 镜像抑制架构的收发器的关键组件。无源 RC-CR 移相器生成所需的两个正交输出，在所需带宽上具有准确的 90° 相移，但缺乏所需的幅度匹配精度。提出了 RC-CR 移相器的 90 nm CMOS 微电子实现，其中有源电阻器通过集成的在线 ALL 校准系统进行调整，以在所需的带宽上保持正交输出的匹配幅度。在线 ALL 校准系统采用峰值检测器、比较器、数字逻辑控制和电荷泵以增量调整有源电阻器，同时收敛到匹配的幅度，类似于具有相位频率检测器和电荷泵的锁相环的操作。由此产生的 90 nm 实现支持 - 40db 到 - 70db 镜像抑制比 (IMMR) 在 IF 170 MHz 至 330 MHz 带宽上。考虑到基于 200 次 Monte Carlo 模拟的工艺变化，90 nm CMOS 实现是全功能的。