NTSC rejection filter
US6226049A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 31, 1997 |
| Grant date | May 1, 2001 |
| Priority date | — |
| Expiry date | Oct 31, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/21
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A receiver including an NTSC rejection filter for eliminating interference signals from a high definition signal. The ratio of the energy of an expected high definition signal to the energy of an NTSC signal is determined. An NTSC signal sequence is generated according to the determined ratio. The number of filter taps is determined, and an autocorrelation matrix of the NTSC signal is calculated using the generated NTSC signal sequence. The power of all interference noise in the output of the NTSC rejection filter is used as a cost function, with respect to the input NTSC interference signal, the additive Gaussian noise and the VSB signal. A filter coefficient equation, for minimizing the cost function, is obtained by differentiation, and then the autocorrelation matrix is substituted for the equation, to calculate coefficients of the NTSC rejection filter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.