Patent · US Expired

FMX stereophonic receiver

US4852167A · kind A · utility

3Cited by
8References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 14, 1988
Grant dateJul 25, 1989
Priority date
Expiry dateJan 14, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03G7/008
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

An FMX stereophonic receiver receives an FMX stereophonic broadcast signal which includes a stereo sum signal, an uncompressed stereo difference signal, and a compressed stereo difference signal which is formed by modulating the uncompressed stereo difference signal by a quadrature modulation and being compressed. The FMX stereophonic receiver includes an FM detector for producing an FM detection signal including a stereo pilot signal, a PLL circuit for producing a signal which is in a synchronized relationship with the stereo pilot signal included in the FM detection signal, a synchronous detection circuit for receiving the FM detection signal and for producing the uncompressed stereo difference signal in accordance with the signal produced from the PLL circuit, a quadrature detection circuit for receiving the FM detection signal and for producing the compressed stereo difference signal in accordance with the signal produced from the PLL circuit, and a phase shifting means for shifting the phase of at least one of the FM detection signal applied to the PLL circuit and the FM detection signal applied to the detection circuits so as to correct the phase difference between the synchr…

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