Patent · US Expired

Frame-based spectral shaping method and apparatus

US6255967A · kind A · utility

4Cited by
8References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 7, 1999
Grant dateJul 3, 2001
Priority date
Expiry dateDec 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.