Method and system for selecting effective tap values for a digital filter
Systems and methods are provided for determining effective tap values for a digital filter. A first plurality of vectors is generated, wherein each of the first plurality of vectors represents a set of tap values for the filter at a first resolution. A best vector is selected from the first plurality of vectors according to a first performance metric. A second plurality of vectors is generated within a threshold distance of the selected best vector, wherein each of the second plurality of vectors represents a set of tap values for the filter at a second resolution that is superior to the first resolution. A best vector is selected from the second plurality of vectors according to a second performance metric.
1. An apparatus, comprising:
a digital filter having a input for receiving tap values; and
an optimization system for supplying tap values to the input of the digital filter, the optimization system including:
a tap selector that establishes a search space of vectors, where a given vector represents a set of tap values for the digital filter at a first resolution, and selects a vector from the established search space; and
a filter evaluator that evaluates the performance of the digital filter configured with the tap values represented by the selected vector and determines a performance metric for the selected vector, the tap selector being operative to select a best vector from the search space of vectors based upon the determined performance metrics for the search space of vectors and to generate a new search space of vectors, each of the vectors in the new search space representing a set of tap values at a second resolution that is higher than the first resolution.
2. The apparatus of claim 1 , wherein the tap selector is operative to generate the new search space of vectors within a threshold distance of the selected best vector.
3. The apparatus of claim 1 , further comprising a test signal generator that provides a test signal, having at least one characteristic associated with an operating environment of the digital filter, to the digital filter to provide a filtered test signal.
4. The apparatus of claim 3 , the filter evaluator being operative to compare the filtered test signal to a reference signal to determine a bit error rate associated with the digital filter as a performance metric for the selected vector.
5. The apparatus of claim 3 , the filter evaluator being operative to evaluate the filtered test signal to determine a frequency response associated with the digital filter as a performance metric for the selected vector.
6. The apparatus of claim 1 , wherein at least one of the tap selector and the filter evaluator is implemented as software on a computer readable medium.