Patent · US Expired

Digital demodulator

US6813321B1 · kind B1 · utility

3Cited by
6References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 21, 2000
Grant dateNov 2, 2004
Priority date
Expiry dateJul 21, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L2027/0095
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A digital demodulator which will need no absolute phasing circuit is provided. A known-pattern BPSK signal generating circuit 6 generates the same known-pattern BPSK signal as a known-pattern BPSK signal in a received digital modulated wave in synchronism with the known-pattern BPSK signal in the received digital modulated wave, a carrier-reproducing phase error detecting circuit 7 has a phase error table where one of reference phases in a signal point position of a demodulation baseband signal is made a convergence point, a phase error voltage corresponding to a phase error between a phase determined from the signal point position of the demodulation baseband signals and a phase convergence point is sent out, by enable-controlling a carrier-reproducing loop filter 8 according to the known-pattern BPSK signal outputted from the known-pattern BPSK signal generating circuit 6, the phase error voltage is smoothed, and carrier reproduction is performed while controlling the frequency of a reproduced carrier according to the smoothed output so that the phase in the signal point position coincides with the phase convergence point.

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