Compact device-level linearisation technique using a reduced complexity derivative superposition approach

An alternative derivative superposition (DS) approach is proposed to reduce nonlinear distortions in field effect transistors (FETs). Based on the conventional DS method, the described technique offers a compromise to intermodulation correction capability and circuit complexity. Intermodulation cancellation is achieved by synthesising a small-ripple transconductance derivative for a given range of input signal levels. The impact of the proposed technique on linearity and gain degradation is analysed and evaluated experimentally. The designed two- section DS-devices show an improvement in third- order intermodulation distortion of more than 7 dB over a dynamic range of 8.4 dB without degrading gain more than 0.25 dB.