Dispersed harmony search algorithm for MESFET DC and small signal model parameter extraction

Abstract

This paper proposes a variant of harmony search algorithm named as dispersed harmony search (DHS) and its application to extract the drain current (DC) and small signal model parameters of Galium Arsenide (GaAs) metal extended semiconductor field effect transistor (MESFET). DHS algorithm is used to minimize the difference between measured and modeled (i) drain current to extract the DC model parameters and (ii) S-parameters to extract the small signal model parameters. The S-parameters are measured in the frequency range of 500 MHz to 25 GHz with a step of 500 MHz. The measured data are obtained from a fabricated MESFET of gate length 0.7 fim and gate width of 600 μm (4 × 150). The performance of DHS algorithm is compared with particle swarm optimization (PSO) and artificial bee colony (ABC) algorithm in terms of quality of solution and execution time to extract the model parameters. Comparison results reveal that the DHS algorithm has better convergence speed and also a robust technique for model parameter extraction compared with PSO and ABC algorithms. © 2012 ICIC International.