CAJ | 학술논문

针对宽带功率放大器的强记忆效应，提出了一种前馈交叉记忆多项式模型。该模型由主信号对消和畸变注入两个环路构成。信号对消环路采用记忆多项式模型对带内动态线性记忆效应进行建模；畸变注入环路采用记忆时刻信号间的交叉记忆项对带外扩展频谱行为进行建模。为克服最小二乘法在模型辨识中带来的数值不稳定问题，采用共轭梯度的方法对模型的参数进行辨识。为消除噪声和测量误差对模型参数辨识带来的影响，采用 ADS 软件包络仿真的方法获取精确的功放输入输出信号复包络数据，并对该模型进行充分的性能分析和评估。实验结果表明，所提方法对宽带功放的非线性动态特性具有很好的逼近能力，特别是带外频谱扩展特性，较之常用的方法提升了近10 dB。
침대관대공솔방대기적강기억효응，제출료일충전궤교차기억다항식모형。해모형유주신호대소화기변주입량개배로구성。신호대소배로채용기억다항식모형대대내동태선성기억효응진행건모；기변주입배로채용기억시각신호간적교차기억항대대외확전빈보행위진행건모。위극복최소이승법재모형변식중대래적수치불은정문제，채용공액제도적방법대모형적삼수진행변식。위소제조성화측량오차대모형삼수변식대래적영향，채용 ADS 연건포락방진적방법획취정학적공방수입수출신호복포락수거，병대해모형진행충분적성능분석화평고。실험결과표명，소제방법대관대공방적비선성동태특성구유흔호적핍근능력，특별시대외빈보확전특성，교지상용적방법제승료근10 dB。
Considering the strong memory effects of the broadband power amplifier,a feedforward cross memory polynomial model is proposed.This model consists of two loops.One is used as a signal cancellation loop which adopts memory polynomial to model dynamic linear memory effect in-band.And the other is used as a distortion injection loop,which adopts memory time signals cross item memory to model spectrum spread be-havior out-of-band.In order to overcome the numerical instability problem of the least-square method,a conju-gate gradient method is used to identify the model coefficients.The ADS envelope simulation method is adopted to obtain accurate complex envelop data of power amplifier input and output signals.This method eliminates the effects of noise and measurement error on the identification of model parameters effectively.The model perform-ance is analyzed and evaluated sufficiently based on the obtained complex envelop data.The experimental results show that the proposed model can achieve good approximation capability for the nonlinear dynamic characteris-tics of the broadband power amplifier,especially the spectrum spread behavior out-of-band.Approximation pre-cision is improved almost 10 dB compared with the common methods.