JSSC 2019第6期RF & Wireless130-nm SiGe BiCMOSPower Amplifier

A 28-/37-/39-GHz Linear Doherty Power Ampliﬁer in Silicon for 5G Applications

本文提出了一种用于5G应用的28-37-39 GHz硅基线性Doherty功率放大器。

28/37/39 GHz, +16.8/+17.1/+17 dBm Psat, 52% -3-dB S21带宽, 40% -1-dB Psat带宽

Doherty功率放大器5G毫米波硅基宽带

▸创新点1：新型变压器基片内Doherty功率合成器 - 该论文提出了一种基于变压器的片上Doherty功率合成器，通过降低功率回退（PBO）时的阻抗变换比（ITR），显著提高了带宽和功率合成效率。这一电路创新在28-39 GHz频段实现了52%的-3 dB小信号带宽和40%的-1 dB大信号饱和输出功率带宽。

▸创新点2：驱动-PA协同设计方法 - 作者开发了一种创新的驱动-PA协同设计方法，通过创建功率依赖的不均匀馈电机制，在不增加硬件开销或牺牲带宽的情况下增强了Doherty PA的性能。这一方法创新使得在5.9-6.7 dB PBO下实现了1.62-1.92倍的效率提升。

▸创新点3：宽带高效功率放大器设计 - 该研究实现了覆盖28/37/39 GHz三个5G频段的宽带高效PA，在130-nm SiGe BiCMOS工艺上集成了1.8 mm²的紧凑设计，同时支持64-QAM调制和多Gbps数据速率，为毫米波5G系统提供了高性能解决方案。

▸创新点4：毫米波多频段集成解决方案 - 该PA设计支持现有毫米波系统的直接升级，并为未来多频段5G大规模MIMO和相控阵平台提供了紧凑的系统解决方案，展示了在28/37/39 GHz频段分别达到+16.8/+17.1/+17 dBm的饱和输出功率。

Abstract

This paper presents the ﬁrst 28-/37-/39-GHz linear Doherty power ampliﬁer (PA) in silicon for broadband ﬁfth- generation (5G) applications. We introduce a new transformer- based on-chip Doherty power combiner that can reduce the impedance transformation ratio (ITR) in power back-off (PBO) and, thus, improve the bandwidth and power-combining efﬁ- ciency. We also devise a “driver-PA co-design” method that creates power-dependent uneven feeding in the Doherty PA and enhances the Doherty operation without any hardware overhead or bandwidth compromise. For the proof of con- cept, we implement a 28-/37-/39-GHz PA fully integrated in a standard 130-nm SiGe BiCMOS process, which occupies 1.8 mm 2. The PA achieves a 52% −3-dB small-signal S 21 bandwidth and a 40% −1-dB large-signal saturated output power (P sat) bandwidth. At 28/37/39 GHz, the PA achieves +16.8-/+17.1-/+17-dBm P sat, +15.2-/+15.5-/+15.4-dBm P 1d B,a n d superior 1.72/1.92/1.62 times efﬁciency enhancement over class-B operation at 5.9-/6-/6.7-dB PBO. Moreover, the PA demonstrates multi-gigabit-per-second data rates with excellent efﬁciency and linearity for 64-quadrature amplitude modulation (64-QAM) in three millimeter-wave (mm-wave) 5G bands. This PA advances the state of the art for Doherty, wideband, and 5G silicon PAs in mm-wave bands. It supports drop-in upgrade for current PAs in existing mm-wave systems and opens doors to compact system solutions for future multiband 5G massive multiple-input multiple-output (M