Evaluation of 2ND and 3RD Order Intermodulation Distortion of Cascaded MESFET´s

2nd and 3rd order intermodulation distortion, IMD, produced in a cascade of GaAs MESFET´s, is, for the first time, evaluated. The conclusions were drawn from both numerical simulations and simple analytic calculations, using Volterra Series techniques, and specific nonlinear device modeling for IMD prediction. Cascode, asymmetric differential pair and common-source chain configurations are addressed, and conditions for IMD reduction are investigated. Laboratory results obtained with such a prototype validate the approach.