Initializing communications in systems using multi-carrier modulation
US6434119B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 7, 1998 |
| Grant date | Aug 13, 2002 |
| Priority date | — |
| Expiry date | Jul 7, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L5/1438
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A variety of methods of initializing a connection between a remote modem and a central unit in a communication system that utilizes a multi-carrier modulation scheme are described. In one aspect of the invention, a relatively long duration single frequency activation signal that ramps up and ramps down in intensity is utilized. In a preferred embodiment, the activation signal is transmitted on a sub-carrier that is outside a range of sub-channels used for data transmission in the multi-carrier modulation scheme. In a separate aspect of the invention, an initialization sequence that includes central synchronization signal, a remote synchronization signal, a central setup signal, a remote setup signal, a central setup complete signal a remote message and a central message. The central unit transmits a central setup complete signal when it has completed a central setup procedure. However, the remote message is only sent after the remote unit has both completed the remote setup procedure and received the central setup complete signal. In one preferred embodiment, during a first superframe of each of the described signals, the transmitting unit sends only header symbols which constitute…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.