Patent · US Active

Phase locked loop frequency synthesizer

US7634041B2 · kind B2 · utility

2Cited by
3References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 28, 2006
Grant dateDec 15, 2009
Priority date
Expiry dateMay 10, 2028

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03L7/1976
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A dynamic carrying method to prevent saturation of a sigma-delta modulator of a phase locked loop frequency synthesizer. The phase locked loop frequency synthesizer using the dynamic carrying method comprises a forward portion receiving a reference frequency signal and a first frequency signal to generate an output carrier signal; a multi-modulus divider dividing the output carrier signal frequency to generate the first frequency signal; a dynamic carrying device receiving and separating transmitting data into a carrying part and a residue part when the transmitting data amplitude exceeds a threshold; a sigma-delta modulator receiving the residue part to generate a first modulus control signal; an auxiliary modulator receiving the carrying part to generate a second modulus control signal; and a first adder receiving the first modulus control signal, the second modulus control signal, and a third modulus control signal and outputting a modulus modulation signal to modulate the multi-modulus divider.

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