Optimum design of a new predistortion scheme for high linearity k-band MMIC power amplifiers

In this paper which won the best paper award at GAAS 2001, a novel predistortion approach well suited for MMIC design is discussed. The theoretical analysis shows third-order intermodulation product (IMP3) cancellation independent of the specific technology exploited for implementation and of the detailed behaviour of the power stage nonlinearity. The active stages of the predistorter are modelled through a non-linear describing function, which can be experimentally characterised through standard LS S-parameter measurements. Significant improvement in the linearity of the Pin-Pout is demonstrated together with IMP3 reduction. A sensitivity analysis on the optimisation parameters shows that this approach is robust and well suited for circuit design.