CA2241408C - Utilisation d'un recepteur ntsc special pour detecter un signal ntsc brouilleur dans le meme canal qu'un signal de television numerique - Google Patents
Utilisation d'un recepteur ntsc special pour detecter un signal ntsc brouilleur dans le meme canal qu'un signal de television numerique Download PDFInfo
- Publication number
- CA2241408C CA2241408C CA002241408A CA2241408A CA2241408C CA 2241408 C CA2241408 C CA 2241408C CA 002241408 A CA002241408 A CA 002241408A CA 2241408 A CA2241408 A CA 2241408A CA 2241408 C CA2241408 C CA 2241408C
- Authority
- CA
- Canada
- Prior art keywords
- signal
- phase
- circuitry
- digital television
- response
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N5/00—Details of television systems
- H04N5/14—Picture signal circuitry for video frequency region
- H04N5/21—Circuitry for suppressing or minimising disturbance, e.g. moiré or halo
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N5/00—Details of television systems
- H04N5/44—Receiver circuitry for the reception of television signals according to analogue transmission standards
- H04N5/455—Demodulation-circuits
Landscapes
- Engineering & Computer Science (AREA)
- Multimedia (AREA)
- Signal Processing (AREA)
- Noise Elimination (AREA)
- Television Receiver Circuits (AREA)
- Color Television Systems (AREA)
- Picture Signal Circuits (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
Abstract
Méthode permettant à un récepteur de télévision numérique de détecter un signal de télévision numérique qui s'accompagne d'un signal NTSC d'amplitude considérable causant du brouillage dans le même canal. La partie vidéo de tout signal NTSC brouilleur dans le même canal est synchrodynée à la bande de base, de manière à produire un résultat de démodulation en phase comprenant un premier ensemble d'artefacts du signal de télévision numérique ainsi qu'un résultat de démodulation en quadrature de phases, comprenant un deuxième ensemble d'artefacts du signal de télévision numérique. Les résultats de la démodulation en quadrature de phases sont déphasés de 90 degrés à des fréquences d'une gamme prescrite, puis les résultats de démodulation en phase et en quadrature de phases sont combinés linéairement afin de générer un résultat de combinaison linéaire essentiellement exempt des premier et deuxième artefacts du signal de télévision numérique dans la gamme de fréquences prescrite. Lorsque l'amplitude du résultat de combinaison linéaire dépasse une valeur prescrite, c'est une indication que le signal de télévision numérique s'accompagne d'un signal NTSC d'amplitude considérable causant du brouillage dans le même canal.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US08/882,540 | 1997-06-25 | ||
| US08/882,540 US5852476A (en) | 1997-03-21 | 1997-06-25 | Using special NTSC receiver to detect when co-channel interfering NTSC signal accompanies a digital tv signal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2241408A1 CA2241408A1 (fr) | 1998-12-25 |
| CA2241408C true CA2241408C (fr) | 2002-04-09 |
Family
ID=25380813
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002241408A Expired - Fee Related CA2241408C (fr) | 1997-06-25 | 1998-06-23 | Utilisation d'un recepteur ntsc special pour detecter un signal ntsc brouilleur dans le meme canal qu'un signal de television numerique |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JP3576816B2 (fr) |
| KR (1) | KR100274743B1 (fr) |
| CA (1) | CA2241408C (fr) |
-
1998
- 1998-06-23 CA CA002241408A patent/CA2241408C/fr not_active Expired - Fee Related
- 1998-06-25 KR KR1019980024181A patent/KR100274743B1/ko not_active Expired - Fee Related
- 1998-06-25 JP JP17944798A patent/JP3576816B2/ja not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH1175134A (ja) | 1999-03-16 |
| JP3576816B2 (ja) | 2004-10-13 |
| KR100274743B1 (ko) | 2000-12-15 |
| KR19990007349A (ko) | 1999-01-25 |
| CA2241408A1 (fr) | 1998-12-25 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed | ||
| MKLA | Lapsed |
Effective date: 20100623 |