Data transmission system
US5548281A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jul 14, 1994 |
| Grant date | Aug 20, 1996 |
| Priority date | — |
| Expiry date | Jul 14, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10H2240/265
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a data transmission system, a center and a plurality of terminals are connected by a coaxial cable. The center is controlled by a server to transmit mode sense polling signals in succession every predetermined time (for example every 30 seconds) to all of the karaoke terminals connected to the center. The center determines whether each terminal is in a karaoke mode or not based on the mode response signal transmitted from each terminal in response to the mode sense polling signals. The center then transmits request polling signal only to terminals determined as being in the karaoke mode, confirms whether a request for a song has been made, and transmits karaoke data to those terminals that have a request.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.