Systems and Methods for Adaptive Echo Cancellation

An adaptive echo canceller embodied in a computer-readable medium that when executed by one or more processors filters sampled data, the adaptive echo canceller, comprising:

• a foreground filter configured with coefficients expected to remove echo induced peaks in a sparse impulse response and calculate a first echo return loss value;
• and
• a background filter configured to:
• bandpass filter and decimate the sparse impulse response;
• repetitively identify the location of one or more peaks in the sparse impulse response;
• confirm one or more identified peaks over a defined number of blocks of the sparse impulse response before defining an active region equally about the one or more identified peaks such that when a peak is confirmed an adaptive normalized least-mean square algorithm is applied to filter the sparse impulse response;
• and
• calculate a second echo return loss value responsive to the filtered sparse impulse response, wherein when the second echo return loss value exceeds the first echo return loss value the coefficients in the foreground filter are replaced with one or more coefficients from the background filter to modify the foreground filter.

An adaptive echo canceller, comprising:

• means for determining the effectiveness of a foreground filter at removing one or more echo induced peaks in a sparse impulse response;
• means for repetitively identifying the location of a user defined number of peaks responsive to a bandpass filtered and decimated representation of the sparse impulse response;
• means for storing a user defined number of peak detection vectors responsive to peaks in the representation of the sparse impulse response;
• means for confirming the location of a peak responsive to the frequency of a respective element within the peak detection vectors;
• means for defining one or more active regions centered about respective confirmed peaks;
• means for background filtering the representation of the sparse impulse response responsive to the one or more active regions;
• means for determining the effectiveness of the means for background filtering at removing peaks in the representation of the sparse impulse response;
• and
• means for comparing the effectiveness of the foreground filter to the effectiveness of the means for background filtering, wherein when the means for background filtering is more effective than the foreground filter, one or more coefficients in the foreground filter are replaced with coefficients associated with the means for background filtering to create an improved foreground filter.