Digital baseband channel signals are received and up-sampled to a common sampling rate. The digital baseband channel signals are filtered using low pass filters. Complex frequency shifting is performed of the filtered digital baseband channel signals based on the associated different channel frequencies to obtain digital channel signals, which are combined to generate a digital wideband multi-channel signal that is a digital representation of an analog wideband multi-channel signal that is based on combining analog channel signals that correspond to the analog baseband channel signals. A non-linear pre-distortion of the digital wideband multi-channel signal is performed, the non-linear pre-distortion adding at least one of a gain and a phase shift to the digital wideband multi-channel signal such that the digital channel signals included within the digital wideband multi-channel signal are compensated for a non-linear distortion effected on the analog wideband multi-channel signal by a high-power amplifier.