Application of the Cardiff Model for Orthogonal LMBA Response Prediction

This paper shows the ability of the Cardiff Behavioural Model to precisely reproduce the response of an advanced power amplifier architecture. The investigation involved varying the phase of the complex load on the isolated port of a 50 W orthogonal load-modulated balanced amplifier operating at 2.5GHz. Leveraging a limited set of data points, the Cardiff model effectively estimates the PA’s performance across a wide range, from approximately 10 dB output backoff to around 1-2 dB of gain compression, with a maximum normalised error of only −20 dB. This novel application of the Cardiff Model offers an efficient means of reducing measurement and simulation time for designing and optimizing this particular type of power amplifier.