Single ended DMT test method for determining ADSL capability of cables
US7583727B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 2002 |
| Grant date | Sep 1, 2009 |
| Priority date | — |
| Expiry date | Dec 24, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/46
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A DMT (Discrete Multi-Tone) test method is employed by a single test device to estimate the theoretical and practical data rates of a cable under test for a pair of target ADSL (Asymmetric Digital Subscriber Line) DMT modems. The DMT test can also be used to analyze the cause of a problem, or to predict a problem, whereby a pair of ADSL DMT modems could fail to synchronize. The method includes (a) measuring the frequency characteristics of the cable with discrete tones; (b) measuring the cable noise and interference for every sub-channel of the whole bandwidth; (c) determining the theoretical and practical data rates for every sub-channel, based on the measured frequency characteristics and noise characteristics, as well as modem parameters selected by the user; and (d) estimating the theoretical and practical data rates for the ADSL bandwidth based on the ADSL DMT standard selected by the user.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.