Noise cancellation with improved frequency resolution

A method of noise abatement within an audio signal stream containing an unwanted signal referred to as a noise signal, comprising:

• acquiring a digitized noise signal from an environment in which the audio signal stream is present, where the digitized noise signal includes a plurality of data samples;
• receiving, by a digital processor circuit, the digitized noise signal;
• for each data sample in the plurality of data samples, appending, by the digital processor circuit, one or more datum to each data sample to form a set of data, where magnitude for each of the one or more datum is zero;
• computing, by the digital processor circuit, a frequency domain representation of the set of data in a frequency domain, wherein the frequency domain representation includes a plurality of noise segments and each noise segment in the plurality of noise segments correlates to a different frequency band;
• individually shifting one or more noise segments in time using the digital processor circuit;
• combining the plurality of noise segments to form a composite anti-noise signal;
• and
• outputting the composite anti-noise signal into the audio signal stream to abate the noise through destructive interference.

A system for noise abatement in an audio signal stream which contains a noise signal, comprising:

• a microphone configured to acquire a noise signal from an environment in which the audio signal stream is present;
• an analog-to-digital converter configured to receive the noise signal from the microphone and operate to convert the noise signal to a digitized noise signal;
• a digital signal processor configured to receive the digitized noise signal from the analog-to-digital converter and, for each data sample in the digitized noise signal, process a given data sample by
• appending one or more datum to the given data sample to form a set of data, where the magnitude for each of the one or more datum is substantially zero,
• computing a frequency domain representation of the set of data in frequency domain,
• shifting the frequency domain representation of the set of data in time, thereby producing a shifted frequency domain representation of the set of data, and
• converting the shifted frequency domain representation of the set of data to time domain to form a portion of an anti-noise signal;
• and
• a digital-to-analog converter configured to receive the anti-noise signal from the digital signal processor and operate to convert the anti-noise signal to an analog anti-noise signal.