Data transmission
US7428244B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 5, 2002 |
| Grant date | Sep 23, 2008 |
| Priority date | — |
| Expiry date | Nov 27, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/6583
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In order to measure the rate at which a terminal 2 can receive data from a source 5, 6, 7 the source temporarily increases it transmitting rate. The time taken to receive these higher-rate transmissions is measured at the terminal (or acknowledged by the terminal and measured at the transmitter) and the rate calculated. Inter alia, these measurements can be used for control of layered coding where apparatus for transmitting signals to video or other terminals 2 has coding means 5 for receiving the signals to generate a base signal stream B which is a coarse representation of the signal to be transmitted and at least one higher order stream E1, E2 containing finer detail of the signal not present in any lower order stream. These streams are sent by transmitting means 6 to the terminals, but at least some of the terminals do not receive all of the higher order streams. Control means 7 receives signals Xk indicative of the measured data-receiving capacity of the terminals and calculates, based on the measured capacities, an adjustment for the coding means to make to the data rates of the streams.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.