US Patent 9660675 Digital predistortion and uptilt and cable communication

Otherwise incompatible digital predistortion and uptilt can be used together, such as in a cable television or other cable communications system having a frequency-dependent signal loss at high frequencies. The predistortion can be used to compensate for a nonlinear gain compression of a power amplifier at higher frequencies. Additional uptilt and equalizer circuits can be included to address deleterious distortion effects that may otherwise arise by using predistortion and uptilt together. Training and adaptation of various components are described. Fine and coarse uptilt adjustments can be provided.