The equivalent circuit of GaAs Schottky barrier diode is modelled and its parameters are determined from measured data. The admittance of the diode with external bias from -1 to 0.6 volt is measured at intervals of 0.1 GHz between 11.7 and 12.2 GHz.
Equivalent 5 circuit parameters of the diode including nonlinear conductance and capacitance are calculated by a computer optimization program from the 5 measured data points of different frequencies. This result is compared with the theoretical values of the diode in the low frequency region.