基于Ritz-Galerkin方法的太赫兹二极管检波器非线性分析

Nonlinear analysis of diode detector in THz based on Ritz-Galerkin method

肖特基二极管检波器是太赫兹ASK/OOK通信系统的关键器件之一,为了更好地分析肖特基二极管检波器的非线性特性,从检波器的电路模型出发,基于Ritz-Galerkin方法,建立了检波器非线性特性的理论分析模型。并利用模型对检波器输出信号强度和灵敏度作了理论预测,表明该理论模型能够精确预测检波器的非线性特性。最后利用该理论模型研究了输入信号强度、负载阻抗和外界温度对0.34 THz肖特基二极管检波器非线性特性的影响。结果表明随着功率的增加,检波器由平方率区渐变至线性区只在特定条件下才成立,在实际条件下很容易出现高阶效应。

Schottky diode detector is one of the key devices of THz wireless communication system.In order to make further research on the nonlinear characteristic of a Schottky diode detector(SBD),a model was established based on Ritz-Galerkin method.Meanwhile,the model has been used to predict the output and the sensitivity of the detector,which indicates this model can precisely predict the performance of the detector.Finally,the influences of the power levels,load resistance and temperature on nonlinearity behavior of the SBD in 0.34 THz were investigated by this model,which indicates that the diode detectors exhibit true square-law to a linear law with an increase of power level is correct only under restrictive conditions,and that slopes corresponding to higher-order effect can be easily encountered in practical situations.