Fiber optic telecommunication system employing continuous downlink, burst uplink transmission format with preset uplink guard band
US5457560A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 16, 1994 |
| Grant date | Oct 10, 1995 |
| Priority date | — |
| Expiry date | May 16, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/22
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A fiber optic telecommunication system has master site linked to a plurality of subscriber interface sites by a single pair of optical fibers. Downlink messages are transmitted in a continuous TDM format over a first optical fiber from the master site to subscriber interface sites, and in a burst mode TDMA format over a second optical fiber from the subscriber interface sites to the master site. Each subscriber interface site is coupled to the optical fiber link by way of a multiple fan-out fiber coupling pedestal at a common location on the fiber pair. To prevent collisions between successive uplink bursts from the subscriber interface sites, a guard band separates successive uplink messages from one another. The guard band duration accommodates optical fiber transmission distance between the common location on the uplink optical fiber and the subscriber interface site whose differential optical fiber transmission distance from the common location is greatest. A subscriber location has a television decoder associated with the subscriber's television set, through which television channel selection signals are input by the subscriber for transmission from the subscriber interface si…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.