Digital pre-distortion (dpd) estimation window search

A method for performing digital pre-distortion (DPD) on input signal samples, the method comprising:

• determining a signal power characteristic for each pre-distorted sample of a plurality of pre-distorted samples corresponding to input signal samples;
• selecting a subset of the plurality of pre-distorted samples based on the determined signal power characteristics, the subset of the plurality of pre-distorted samples selected to fit within a predetermined estimation window size;
• updating a plurality of DPD coefficients based on the subset of the plurality of pre-distorted samples;
• and
• performing pre-distortion of new input signal samples based on the updated DPD coefficients to generate a subsequent plurality of pre-distorted samples for transmission.

An estimation window search apparatus comprising:

• a counter circuit configured to increment a sample counter and assign indices to a plurality of input samples;
• a power threshold comparison circuit configured to determine a signal power characteristic for each input sample of the plurality of input samples;
• and
• a circular buffer configured to store a subset of the assigned indices corresponding to a subset of the plurality of input samples, the subset of the plurality of input samples selected based on the determined signal power characteristics, and the subset of the plurality of input samples further selected to fit within a predetermined estimation window size,