Optimization technique for FIR and IIR filter design

A digital signal processing system including a digital filter with a performance tolerance that produces an output signal from samples of an input signal, comprising:

• delay elements that produce delayed samples of the input signal;
• filter coefficients that multiply the delayed samples of the input signal to produce products;
• and
• an adder that sums the products, wherein the filter coefficients are selected by a filter coefficient search process that includes scaling the filter coefficients to reduce a filter implementation cost while satisfying the filter performance tolerance.

A method of configuring a digital filter with a performance tolerance to produce an output signal from samples of an input signal, comprising:

• producing delayed samples of the input signal with delay elements;
• multiplying the delayed samples of the input signal by filter coefficients to produce products;
• and
• summing the products with an adder, wherein the filter coefficients are selected by employing a filter coefficient search process that includes scaling the filter coefficients to reduce a filter implementation cost while satisfying the filter performance tolerance.

A method of designing a digital filter with a performance tolerance to produce an output signal from samples of an input signal, comprising the steps of:

• designing an original filter with filter coefficients;
• selecting a number of nonzero binary digits;
• identifying a filter performance tolerance;
• choosing a binary precision;
• selecting a set of scale factors;
• computing binary filter coefficients for the filter coefficients scaled by a scale factor and limiting the number of nonzero binary digits in each scaled filter coefficient;
• and
• selecting a filter with binary filter coefficients with the limited number of nonzero binary digits that satisfies the filter performance tolerance.