V.P. Meshchanov, A.L. Khvalin
In modern systems of the automated designing (САD) for modeling field transistors equivalent Materka scheme is widely used. At absence of model of the transistor in standard CAD libraries there is a necessity of creation of adequate model of the transistor. As initial data for modeling it is possible to use information sheets of manufacturers electronic a component with results of measurements of key parameters.
In clause the technique of creation of Materka model on the basis of measured peak and phase characteristics S-of parameters in a superwide strip of frequencies from 1 up to 22 GHz on an example of field transistor MGF4941AL of firm MITSUBISHI SEMICONDUTOR is resulted.
At the decision of a problem of approximation of experimental characteristics (the module and phase S11, S21, S12, S22) are used known methods of parametrical optimization (a method of gradient, Simplex, Robust and so forth). Owing to significant complexity of a task in view inevitably there is a divergence of initial and optimum characteristics.
The way of specification of characteristics of received Materka model at which functions of a mistake are approximated by a universal sedate polynom is offered, and then develop with optimum characteristics. As a result initial characteristics of the transistor with high accuracy generating by means of equivalent scheme Матерка with the amendment in the form of analytical function from частоты-a sedate polynom with an optimum set of corresponding factors. Results of an estimation deviations from initial characteristics are resulted.