Amplifier with wideband digital predistortion

Linearized amplification apparatus for amplifying an input signal, comprising:

• digital processing circuitry, which comprises:
• a correction circuit, which receives a stream of samples of the input signal at a high sample rate and applies a predistortion correction to the samples;
• and
• a decimation circuit, which receives the corrected samples from the correction circuit and reduces the sample rate of the stream to a reduced rate substantially less than the high sample rate;
• a modulator, which generates a modulated signal responsive to the sample stream from the digital correction circuitry;
• and
• an amplifier, which amplifies the modulated signal, such that distortion in a signal band within a Nyquist zone corresponding to the reduced sample rate is substantially reduced.

A method for linearization of an amplifier having a given distortion characteristic, comprising:

• receiving a stream of samples of an input signal, the stream having a high sample rate;
• applying a predistortion correction to the samples responsive to the given distortion characteristic;
• reducing the sample rate of the stream of corrected samples to a reduced rate substantially less than the high sample rate;
• and
• outputting the corrected, filtered samples for amplification by the amplifier.