Channel switching control for a communication system
US6229790A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 29, 1998 |
| Grant date | May 8, 2001 |
| Priority date | — |
| Expiry date | Jan 29, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/84
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A central controller, such as an RF distribution shelf (RFDS) of a hybrid fiber/coax (HFC) access system, keeps track of the different channels assigned to different remote units, such as the network interface units (NIUs) of the HFC system. Information about the different channel assignments (e.g., for upstream channels) is broadcast to the remote units as part of the overhead bits in each of the downstream channels. Each remote unit monitors the broadcast messages and, over time, updates its own version of the data structure containing the channel assignments, as appropriate. In one embodiment, the central controller also transmits a second type of broadcast message indicating when changes in the channel assignments occur. In this embodiment, the second type of broadcast message is transmitted more frequently than the entire data structure containing the channel assignments, and the remote units only update their copies of the data structure when the second type of broadcast message indicates a change in the data structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.