Patent · US Expired

PCM receiver with lock state control

US4949356A · kind A · utility

4Cited by
5References
24Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 30, 1988
Grant dateAug 14, 1990
Priority date
Expiry dateJun 30, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L27/2277
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Lock state control is provided for the demodulator in a PCM receiver, including those demodulators using quadrature frequency shift keying, by selectively incrementally changing the phase of the received modulated carrier or of the "down converting" local oscillator. Switching means are provided to selectively shift the phase in multiples of 360/N degrees, where N is the number of available demodulation lock states, such as the number 4 in a quadri-phase system.

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