Frame-based spectral shaping method and apparatus
US6255967A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 7, 1999 |
| Grant date | Jul 3, 2001 |
| Priority date | — |
| Expiry date | Dec 7, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/4927
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An improved DC compensation method for use in conjunction with telephony signalling. The method includes defining a frame that includes at least two n-bit codewords. An unsigned codeword is then identified within the frame by applying a rule to the codewords in the defined frame. Next, a sign bit is appended to the unsigned codeword, thereby producing a DC compensating codeword. The sign bit is selected based upon a weighting function of the linear values associated with previously transmitted codewords. The remaining unsigned codewords in the frame are assigned sign bits from user data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.