Experimental verification of intermodulation distortion models for multicarrier satellite systems

Due to the development of high throughput satellites, the multicarrier mode operation of high power amplifiers in the satellite transponders is nowadays a growing trend. This tendency poses new challenges in the design of algorithms able to mitigate the impairments induced by the nonlinear behavior of such amplifiers. One of these challenges is the construction of an accurate low complexity model of the distorted signals. In this work, simplified Volterra based models of a multicarrier satellite transmission chain are considered, and their ability to precisely model intermodulation distortion at the output of a measurement testbed is assessed using a normalized mean squared error criterion. Using a faster-than-Nyquist signaling strategy for the modulation of the signal carriers, it is emphasized how parameters like the input power backoff, the carrier spacing and the symbol duration can influence the precision of the models.