A 26--28 GHz Quadrature-Phase Load-Modulated Balanced Amplifier With Inherent Gain Compression Elimination

IF 5.2 1区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

IEEE Transactions on Microwave Theory and Techniques Pub Date : 2026-09-01 Epub Date: 2026-07-14 DOI:10.1109/TMTT.2026.3711938

Haoyang Jia;Ruijia Liu;Lin Qi;Anding Zhu

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引用次数: 0

Abstract

Load-modulated balanced amplifiers (LMBAs) offer compelling efficiency advantages over broad frequency ranges, but their inherent gain compression in the power back-off (PBO) region poses a significant linearity challenge for modern 5G millimeter-wave applications where digital predistortion (DPD) is difficult to deploy. This article presents a quadrature-phase LMBA (QLMBA) that addresses this limitation through a quadrature-phase control signal injection technique. By establishing a 90° phase offset between the balanced amplifier (BA) and control amplifier (CA), the proposed architecture isolates BA and CA power contributions, suppressing the nonlinear gain compression inherent to conventional LMBA designs. A theoretical analysis demonstrates that, with a properly selected CA to BA drive ratio, gain compression can be fully eliminated. Additionally, a reactive compensation network is integrated into the BA output matching network (OMN) to mitigate the imaginary admittance variation introduced by quadrature load modulation (QLM), improving back-off efficiency. A proof-of-concept 26–28 GHz QLMBA fabricated in a 0.12-

$\mu $

m gallium nitride (GaN) HEMT process achieves saturated output power of 32.3 dBm, drain efficiency of 29.3% at peak and 20.71% at 6-dB PBO at 27 GHz, with less than 1 dB gain compression across the full power range. When driven by 100/400 MHz 5G New Radio (NR) frequency range 2 (FR2) 64 QAM signals, the QLMBA achieves an adjacent channel leakage ratio (ACLR) of −34.2/−30.6 dBc and an error vector magnitude (EVM) of 4.5%/5.5% without DPD, demonstrating its suitability for next-generation millimeter-wave transmitters.

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具有固有增益压缩消除的26—28 GHz正交相位负载调制平衡放大器

负载调制平衡放大器（lbas）在宽频率范围内具有令人信服的效率优势，但其在功率回退（PBO）区域的固有增益压缩对难以部署数字预失真（DPD）的现代5G毫米波应用构成了重大的线性挑战。本文介绍了一种正交相位LMBA (QLMBA)，通过正交相位控制信号注入技术解决了这一限制。通过在平衡放大器（BA）和控制放大器（CA）之间建立90°相位偏移，该架构隔离了BA和CA的功率贡献，抑制了传统LMBA设计固有的非线性增益压缩。理论分析表明，选择适当的CA / BA驱动比，可以完全消除增益压缩。此外，将无功补偿网络集成到BA输出匹配网络（OMN）中，以减轻正交负载调制（QLM）引入的虚导纳变化，提高回退效率。采用0.12- $\mu $ m氮化镓（GaN） HEMT工艺制造的26-28 GHz QLMBA的概念验证实现了32.3 dBm的饱和输出功率，峰值漏极效率为29.3%，27 GHz时6 dB PBO时的漏极效率为20.71%，在全功率范围内的增益压缩小于1 dB。当由100/400 MHz 5G新无线电（NR）频率范围2 (FR2) 64 QAM信号驱动时，QLMBA在无DPD的情况下实现了- 34.2/ - 30.6 dBc的相邻信道泄漏比（ACLR）和4.5%/5.5%的误差矢量幅度（EVM），证明了其适用于下一代毫米波发射机。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

IEEE Transactions on Microwave Theory and Techniques 工程技术-工程：电子与电气

CiteScore

8.60

自引率

18.60%

发文量

486

审稿时长

6 months

期刊介绍： The IEEE Transactions on Microwave Theory and Techniques focuses on that part of engineering and theory associated with microwave/millimeter-wave components, devices, circuits, and systems involving the generation, modulation, demodulation, control, transmission, and detection of microwave signals. This includes scientific, technical, and industrial, activities. Microwave theory and techniques relates to electromagnetic waves usually in the frequency region between a few MHz and a THz; other spectral regions and wave types are included within the scope of the Society whenever basic microwave theory and techniques can yield useful results. Generally, this occurs in the theory of wave propagation in structures with dimensions comparable to a wavelength, and in the related techniques for analysis and design.