Method and apparatus for insertion loss estimation in wireline communications
US6516049B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 2001 |
| Grant date | Feb 4, 2003 |
| Priority date | — |
| Expiry date | Jun 6, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M3/30
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The current invention provides a method and apparatus for determining insertion loss in wireline communication systems. The method may be implemented with any modulation protocol but is particularly suited for multi-carrier modulation protocols such as discrete multi-tone (DMT). The method for calculation of the insertion loss uses a received signal and a discrete subset of frequency ranges, e.g. DMT tones, within that signal. For each of the subset of frequency ranges the average received power on each of the selected set of tones is determined. Next the average power on each received subset of tones is converted to log2 using a simple log2 estimation circuit that avoids the complexity associated with log tables and other prior art methods of computing logarithms. Then the sum of the log2 of the average power received in each of the selected subset of tone bins is determined. Next, the known transmitted power for the selected subset of tones is expressed as log2, is summed and is then subtracted from the sum of the log2 of the average power received. Then using a simple electrical length estimation circuit the insertion loss is calculated. A corresponding apparatus is disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.