采用目标函数计算GaAsMESFET小信号等效电路的新方法

A New Approach to Determining Elements in a Small Signal Equivalent Circuit of GaAs MESFET′s Using Objective Functions

提出了一种计算GaAsMESFET器件小信号等效电路的简单方法。本征元件由传统解析参数变换技术计算,且作为非本征元件的函数。等效电路由集中元件构成,在整个测量频率范围内适用。非本征元件可以作为优化标准本征元件的方差,构成目标函数,进行迭代计算。在0至10GHz频宽内选取10多个不同的偏置点,计算结果与测量的S参数相吻合。

A simple approach to determining a small signal equivalent circuit of GaAs MESFET′s is presented.Intrinsic elements determined by a conventional analytical parameter transformation technique are described as functions of extrinsic elements.Assuming that the equivalent circuit composed of lumped elements is valid over the whole frequency range of the measurements,the extrinsic elements are iteratively determined using the variance,consisting of the objective functions,of the intrinsic elements as an optimization criterion.Measurements of S parameters up to 10 GHz at more than 10 different bias points confirmed that the MESFET equivalent circuit is consistent with calculated S parameters for most bias points.