System and method for providing near optimal bit loading in a discrete multi-tone modulation system
US6459678B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 1, 1998 |
| Grant date | Oct 1, 2002 |
| Priority date | — |
| Expiry date | Dec 1, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L5/0044
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A communication system is disclosed in which information is transmitted using DMT modulation. The communication system includes first logic that is used to measure the response of each of the DMT subchannels and second logic that is used to adapt an equalizer filter associated with each of the DMT channels based on the response measurements. The system further includes third logic that measures the noise variance for each of the DMT subchannels. Using the noise variance measurements, fourth logic is used to assign the number of bits for transmission on each DMT subchannel such that total transmit power is minimized for a fixed data rate. Equations are provided for calculating a near optimal bit load allocation for the DMT subchannels and for calculating the total number of bits to be allocated to the DMT subchannels in a single encoding interval when total transmission power is limited.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.