A method is provided for reducing power dissipation within a communications system
having a plurality of adaptive filters with a plurality of taps, each tap is switchable
between an active and an inactive state, each tap also has a coefficient. An acceptable
error for the system is specified. This error is typically the mean squared error
of the system. A tap threshold is set for each active tap. Those taps having a
coefficient with an absolute value less than the tap threshold set for the active
tap are deactivated. The error of the system is computed and compared to the acceptable
system error. If the computed system error is less than the acceptable system error,
the tap threshold for each active tap is increased. The process of comparing the
tap coefficients to the tap thresholds, deactivating taps with a coefficient less
than the tap threshold and computing the resulting system error is repeated until
the computed system error approaches the acceptable system error without exceeding
the acceptable system error. In addition, the previously deactivated taps may be
periodically activated and their coefficients once again compared to the tap threshold.
If a coefficient is less than the tap threshold the tap is again deactivated. If
a coefficient is greater than the tap threshold, the tap remains active.
