Impulse noise reducer detecting impulse noise from an audio signal
US6795559B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 28, 2000 |
| Grant date | Sep 21, 2004 |
| Priority date | — |
| Expiry date | Oct 13, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/1027
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An impulse noise reducer detects impulse noise in an audio signal by detecting and smoothing the high-frequency amplitude of the audio signal, attenuating the non-smoothed amplitude according to the smoothed amplitude, and comparing the attenuated amplitude with a threshold. Impulse noise is discriminated from high-frequency audio components because the latter tend to occur in longer-lasting bursts and are therefore attenuated more strongly. The impulse noise reducer is simplified because it does not have to perform intermediate-frequency signal processing, and its sensitivity is not affected by adjacent-channel signals because these signals are substantially absent from the audio signal. The impulse noise reducer can be implemented by digital signal processing, and is suitable for use in a medium-wave AM audio broadcast receiver.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.