Joint optimization of data predistortion and baseband pulse shaping in high speed transmission nonlinear systems

The optimization of baseband processing is proposed to compensate for high power amplifier (HPA) nonlinear distortion and channel noise, and to meet an output spectral constraint without the use of a spectral containment filter. Global compensation data predistortion with memory and square root raised cosine pulse shaping are employed, and the spectral regrowth and nonlinear intersymbol interference are evaluated as functions of the average output power back-off of the HPA and the roll-off of the pulse. These parameters are then jointly optimized by minimizing the total degradation subject to the output spectral constraint. Results are given for single carrier 12/4-QAM with 750MHz symbol rate and a standard HPA model.