Digital data over voice communication
US4953160A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 24, 1988 |
| Grant date | Aug 28, 1990 |
| Priority date | — |
| Expiry date | Feb 24, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M11/062
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A method and apparatus is described for transmitting and receiving data signals and voice band signals over a single pair of wires, wherein the energy content of the data signals in the voice bands is transferred to a higher frequency to avoid interference between the two. This is accomplished by sinusoidally encoding the data pulses in the frequency domain. The encoding is equivalently performed in the time domain by linearly combining weighted delayed and advanced versions of the data pulses, in accordance with a weighting formula. A transversal filter is used to multiple delayed and advanced versions of the data pulses by a scaling factor times the ratio of m!/(m-i)!i! factorial wherein i is the ith version being weighted, m is an integer greater than one and ! indicates the factorial function.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.