Patent · US Expired

Direct-conversion receiver for digital-modulation signal

US6236690A · kind A · utility

13Cited by
10References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 14, 1999
Grant dateMay 22, 2001
Priority date
Expiry dateJun 14, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B17/318
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A direct-conversion receiver includes a local oscillator for generating a local oscillator signal, a converter circuit for converting a received radio signal into a pair of a baseband I signal and a baseband Q signal in response to the local oscillator signal, a demodulator for demodulating the pair of the baseband I signal and the baseband Q signal into a demodulation-resultant signal which is neither an I signal nor a Q signal, a detector circuit for detecting a difference between a frequency of the local oscillator signal and a frequency of a carrier of the received radio signal, a clock signal generator for generating a first clock signal providing a timing which corresponds to a center of a symbol period, a signal delay device for delaying the first clock signal to provide a second clock signal, and a symbol deciding circuit for deciding a logic state of the demodulation-resultant signal at a timing determined by the second clock signal.

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