Predicting CDMA spectral regrowth using a general statistical behavioural model for power amplifiers with memory effects

Multi-stage high power amplifiers require more accurate behavioural models to provide a better description of memory effects and highly nonlinear characteristics than memoryless models based on single-tone transfer characteristics. This is achieved using measured two-tone transfer characteristics of the amplitude and phase of the fundamental, IM3 and IM5 components, which has highly nonlinear components that represent the amplifier´s significant memory. A statistical technique is then applied which allows accurate, fast and efficient prediction of spectral regrowth in terms of the adjacent channel power ratio (ACPR) of the communication system without time-consuming time-domain simulations.