US 6,993,544 B2 · Limit-cycle oscillation suppression method, system, and computer program product

Abstract

Limit-cycle oscillations are caused by the compounding of quantization errors that occurs when previous digital filter outputs are used as inputs to the digital filter for the current operation. Where a signal in a digital waveform has become a constant common value applied to the input of the digital filter (indicative that the digital waveform has suspended conveyance of data), limit-cycle oscillations often appear as “random” outputs, with values different from the common value, that occur long after the signal in the digital waveform has become the constant common value. Limit-cycle oscillations are manifested as noise in the filtered digital waveform. Such noise hampers the ability of the system to extract the signal from the filtered digital waveform. The present invention identifies the occurrence of a limit-cycle oscillation as an output different from the common value. The identified limit-cycle oscillation is set equal to the common value.

Claims30

Dependent claims

A method to suppress a limit cycle oscillation from a digital circuit that produces a stream of discrete values, comprising the steps of:

(1) detecting N consecutive discrete values from the stream of discrete values that all have a common value;
(2) comparing a subsequent discrete value after the N consecutive discrete values to the common value;
and
(3) setting the subsequent discrete value equal to the common value if the subsequent discrete value does not equal the common value.

1 more element

A computer program product for suppressing a limit-cycle oscillation from a digital circuit that produces a stream of discrete values, said computer program product having computer program code embodied in a computer readable storage medium, said computer program code comprising:

a first program code means for causing said computer system to detect N consecutive discrete values from the stream of discrete value that all have a common value;
a second program code means for causing said computer system to compare a subsequent discrete value after the N consecutive discrete values to the common value;
and
a third program code means for causing said computer system to set the subsequent discrete value equal to the common value if the subsequent discrete value does not equal the common value.

1 more element

Dependencies are inferred from the claim text.

Limit-cycle oscillation suppression method, system, and computer program product

Life of this patent

Limit-cycle oscillation suppression method, system, and computer program product

Life of this patent

Abstract

Claims30