Memory Behavioral Modeling of RF Power Amplifiers

Power amplifiers (PAs) are the most extended and widely used nonlinear devices in communications. Their non- linearities generate distortion both in amplitude and phase of the PA´s output signal. The use of wideband efficient modulations in the last generation systems, such as wideband code-division multiple access (WCDMA) or orthogonal frequency-division multiplexing (OFDM), adds new problems to the use of PAs, due to the memory effects associated with the bandwidth and the increase of distortion by the non-constant envelope. In this paper it is shown the need of taking into account the memory effects in order to get a more accurate model of PA operation. We compare the performance of the memoryless model with some well-known memory models based on memory polynomials and Volterra series using a novel calibration signal.