Reduction of interference in discrete multi-tone (DMT) based communications systems
US6519291B1 · kind B1 · utility
70Cited by
2References
58Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 3, 1998 |
| Grant date | Feb 11, 2003 |
| Priority date | — |
| Expiry date | Feb 3, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L5/143
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An Asymmetric Digital Subscriber Loop (ADSL) Discrete Multi-Tone system has disjoint and adjacent upstream and downstream channels. During the training phase of an ADSL connection, an ADSL DMT transmitter first determines a round trip propagation delay by transmitting a ranging signal to a far-end ADSL endpoint. During the subsequent communications phase, the ADSL transmitter synchronizes transmission of DMT symbols to a reference clock. In addition, the cyclic extensions of each DMT symbol are increased as a function of the propagation delay.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.