应用于C波段的多自由度可调模拟预失真  

Multi-degree-of-freedom tunable analog predistortion circuit for C-band applications

作　　者：陈美华 李军[1] 李淡森 CHEN Meihua;LI Jun;LI Dansen(Faculty of Electrical Engineering and Computer Science,Ningbo University,Ningbo 315211,Zhejiang)

机构地区：[1]宁波大学信息科学与工程学院,浙江省宁波315211

出　　处：《无线通信技术》2025年第1期44-48,共5页Wireless Communication Technology

基　　金：国家自然科学基金(62371266)。

摘　　要：为补偿功率放大器工作在饱和区时带来的幅度增益和幅度相位失真等非线性失真,本文提出了一种基于肖特基二极管的多自由度可调模拟预失真电路。输入信号由该电路的输入端输入,经过四等分威尔金森功分器分为四条支路,每条支路都串联一个基于6个肖特基二极管阵列的反射式非线性电路,再将每个支路的非线性信号合路输出,对后级功放进行线性化。为了增加电路调节的自由度,使每一个肖特基二极管的偏置电压都独立可调。为提高测试的质量和效率,使用自动化测试的方法进行电压调节,可实现更大动态范围的幅度和相位的补偿,同时可以对不同类型的功放进行线性化。基于此原理加工的毫米波(C波段)模拟预失真电路,对中心频率为4.9 GHz的功率放大器进行线性化测试,实验结果表明:该预失真器可以产生约10 dB的增益扩张和约45°的相位压缩,对被测功放的ACLR改善量在13 dBc以上。To compensate for nonlinear distortions including amplitude gain compression and amplitude-phase distortions introduced by power amplifiers operating in the saturation region,this paper proposes a multi-degree-of-freedom tunable analog predistortion circuit based on Schottky diodes.The input signal is fed into the circuit and divided into four branches through a quad-way Wilkinson power divider.Each branch contains a reflective nonlinear circuit in series with an array of six Schottky diodes,followed by combined output of nonlinear signals from all branches to linearize subsequent power amplifiers.To enhance circuit adjustability,each Schottky diode’s bias voltage is made independently adjustable.An automated testing approach is employed to improve measurement quality and efficiency during voltage tuning,enabling broader dynamic range compensation in both amplitude and phase,while accommodating linearization of various power amplifier types.The implemented millimeter-wave(C-band)analog predistortion circuit,operating at 4.9 GHz center frequency,demonstrates through experimental validation:approximately 10 dB gain expansion and 45°phase compression generation,achieving over 13 dBc ACLR improvement in the tested power amplifier.

关 键 词：模拟预失真 肖特基二极管 多自由度 邻信道泄漏比 

分 类 号：TN722.75[电子电信—电路与系统]