Patent ID: 7310382

Claim:
A power amplifier comprising: a level-discretization modulator in series with a mixing and amplifying stage for frequency up-conversion to radio frequency and for switch-based amplification; an error compensation loop comprising: a forward path including at least said mixing and amplifying stage; a negative feedback path configured to generate a feedback signal, said negative feedback path comprising a frequency down-conversion mixer for down-conversion to an initial frequency band; and a subtractor arranged to subtract the feedback signal from an input signal of said forward path to provide negative feedback action for enabling suppression of distortion caused by components of said forward path; and wherein said level-discretization modulator is digital, said forward path further comprises said digital modulator and said feedback path further comprises an A/D-converter and a first wide-band filter arranged before said A/D-converter for filtering the output signal of said forward path in order to average switching glitches from said switch-based amplifying stage, said first wide-band filter having a bandwidth larger than the bandwidth of the input signal to said power amplifier.