Patent · US Expired

Digital demodulator apparatus

US5005186A · kind A · utility

18Cited by
7References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 13, 1988
Grant dateApr 2, 1991
Priority date
Expiry dateOct 13, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L27/38
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A digital demodulation apparatus which has a detector (11) for receiving transmission signals (S.sub.in) modulated under a multivalue quadrature amplitude modulation method in accordance with a honeycomb signal structure point arrangement. The detector produces I channel and Q channel demodulation signals. The apparatus also includes a discriminator (13) which converts the analog demodulation signals (Sa) to digital demodulation signals (Sd), a memory (21) which successively receives said digital demodulation signals (Sd) and reproduces corresponding original data. The read only memory (21) stores data representatives of the honeycomb signal structure point arrangement, and stores polarity bits (P) and error bits (.epsilon.) of the signal points.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.