Adaptive noise cancellation
US5465413A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1993 |
| Grant date | Nov 7, 1995 |
| Priority date | — |
| Expiry date | Mar 5, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/123
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Method and apparatus for reducing or cancelling impulse noise from a signal containing noise. The desired noise-free signal is assumed to have a representative frequency .omega..sub.3, but may have a range of frequencies adjacent to this frequency, and is assumed to have substantially zero amplitude for all frequencies .omega.<.omega..sub.1 and/or for all frequencies .omega.>.omega..sub.2, where .omega..sub.1 <.omega..sub.3 <.omega..sub.2 or .omega..sub.1 <.omega..sub.2. An input (noisy) signal is filtered and analyzed in a narrow frequency region surrounding .omega.=.omega..sub.1 and/or a narrow frequency region surrounding .omega.=.omega..sub.2 to obtain one or two output signal components n.sub.1 (t) and/or n.sub.2 (t), respectively, that, ideally, contain no contribution from the desired signal. The input signal is also filtered and analyzed in a narrow frequency region surrounding .omega.=.omega..sub.3 to obtain an output signal s(t)+n.sub.3 (t) component including the desired signal s(t). A linear combination of signals, such as S(t)=s(t)+n.sub.3 (t).+-.[n.sub.1 (t)n.sub.2 (1)] .sup.1/2, or S(t)=s(t)+n.sub.3 (t)+.alpha.exp(-j.phi.) [n.sub.1 (t)n.sub.2 (1)].sup.1/2,or S(t)=s(t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.