US 12,206,381 B2 · Filter chains with improved signal to noise ratio

Abstract

Methods and apparatus are provided for adapting gain elements in digital filter chains. In one example, a digital filter chain includes a first digital filter and a second digital filter having an input coupled to an output of the first digital filter. A common gain is applied to signal samples passing between the first digital filter and the second digital filter, the common gain corresponding to a product of an output gain associated with the first digital filter and an input gain associated with the second digital filter. In another example, a digital filter includes an adjustable input gain element and an adjustable output gain element. The adjustable input gain element is configured to apply a gain value to an input signal sample, the gain value comprising a resultant difference of a bitshift configured for the digital filter and a bitwidth extension value. The adjustable output gain element is configured to apply an opposite of the gain value to an output signal sample.

Claims13

Dependent claims

A digital filter chain comprising:

a first digital filter;
and
a second digital filter having an input coupled to an output of the first digital filter;
and
a common gain element disposed between the first digital filter and the second digital filter configured to apply a common gain to signal samples passing between the first digital filter and second digital filter, wherein the common gain corresponds to a product of an output gain associated with the first digital filter and an input gain associated with the second digital filter.

2 more elements

A digital filter chain comprising:

a first infinite impulse response (IIR) filter;
and
a second infinite impulse response (IIR) filter having an input coupled to an output of the first infinite impulse response (IIR) filter;
and
wherein a common gain is applied to signal samples passing between the first IIR filter and the second IIR filter, the common gain corresponding to a product of an output gain associated with the first IIR filter and an input gain associated with the second IIR filter, wherein
the output gain of the first IIR filter and the input gain of the second IIR filter are selected such that a resulting common gain is one.

3 more elements

Dependencies are inferred from the claim text.

Filter chains with improved signal to noise ratio

Life of this patent

Filter chains with improved signal to noise ratio

Life of this patent

Abstract

Claims13