Patent · US Expired

System for frequency modulation

US4547751A · kind A · utility

3Cited by
4References
8Claims
0Family size

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Inventors

Key dates

Filing dateMay 6, 1983
Grant dateOct 15, 1985
Priority date
Expiry dateMay 6, 2003

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03C3/00
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A system for frequency modulation which generates first and second signals having different frequencies in a switching manner in accordance with the logical value of an input signal. The system includes an oscillator for generating a signal having a predetermined frequency; first and second frequency-dividers for subjecting the signal generated by the oscillator to frequency division by different integers l and m to generate first and second signals which are synchronized with each other; a third frequency-divider for subjecting an output signal from said second frequency-divider to frequency division by an integer n selected so that the product m.times.n is the least common multiple of l and m; a control device for controlling input data with an output signal from said third frequency-divider; and a switching device for selecting one of the output signals from the first and second frequency-dividers in accordance with the logical value of an output signal from the control device to generate an output which is passed through a filter for providing a modulated output.

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