Method and apparatus for expanding band of audio signal
US6829360B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 12, 2001 |
| Grant date | Dec 7, 2004 |
| Priority date | — |
| Expiry date | Jan 12, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L21/038
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A low-pass filter of over-sampling type oversamples an input digital audio signal T1 and filters and removes the low frequency components of the produced aliasing noise. A spectrum analyzer circuit calculates the spectrum intensity of a predetermined band of an output signal from the low-pass filter. An expanded signal generating circuit generates an expanded signal having frequency components of the output signal from the low-pass filter. A level control circuit controls the level of the expanded signal according to the spectrum analyzer circuit. An adder adds the level-controlled expanded signal to the output signal from the low-pass filter thereby to generate a digital audio signal T2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.