Differential Evolution Algorithm for MESFET Small Signal Model Parameter Extraction

This paper presents an application of Differential Evolution (DE) technique to extract small signal model parameters of GaAs metal extended semiconductor field effect transistor (MESFET). DE algorithm is used to minimize the difference between measured and modeled S- parameters to extract the small signal model parameters of the MESFET. The performance of DE algorithm in terms of quality of solution and extraction time are compared with Particle Swarm Optimization (PSO) algorithm. The measured data are obtained from a fabricated MESFET of gate length 0.7 μm and gate width of 600 μm (4 × 150). The S parameters are measured in the frequency range of 500 MHz to 25 GHz. The simulation results illustrate that DE technique extracts all 16 small signal model parameters of MESFET accurately and efficiently. The efficiency of this approach is demonstrated by a good fit between the measured and modeled S-parameter over a frequency range of 0.5 to 25 GHz.