On-demand digital information delivery system and method using signal fragmentation and linear/fractal sequencing.
US5737009A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 4, 1996 |
| Grant date | Apr 7, 1998 |
| Priority date | — |
| Expiry date | Apr 4, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/6143
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Digital information is delivered on-demand through satellites and other predominantly broadcast transmission systems to local subscribers by fragmenting each digital item into a sequence of ordered fragments and sequencing them based upon the incidence of subscriber requests. Linear and fractal sequencers are used to schedule the fragments when the incidence of requests is respectively below and above a threshold. The linear sequencer responds to the first request by scheduling the item's fragments in order at successive time intervals and responds to each successive request by adding only those fragments that the existing schedule cannot accommodate. The fractal sequencer computes a full fractal sequencing pattern, in which the fragments are scheduled with broadcast periods less than or equal to their fragment numbers, and based upon the incidence of requests deletes the fragments in the full pattern that are not required to satisfy the subscribers' requests. A hybrid sequencer combines the linear and fractal sequencers to minimize the average bandwidth needed to service infrequent requests and places an upper bound on the peak bandwidth required to service frequent requests.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.