Patent · US Expired

Frequency synthesizer apparatus

US4105949A · kind A · utility

23Cited by
2References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 15, 1977
Grant dateAug 8, 1978
Priority date
Expiry dateApr 15, 1997

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03B21/02
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A frequency synthesizer, responsive to a reference signal having a frequency f.sub.r, for supplying an output signal at a frequency selectable from M times N signal frequencies (where M and N are preselected integers) is disclosed. In each disclosed arrangement, a set of M signals that are each harmonically related to f.sub.r is derived by a cascade connected harmonic generator and comb filter, and a set of M signals that are each harmonically related to f.sub.r /M is derived from the reference signal by a cascaded frequency divider, harmonic generator and comb filter. Each of these signal frequencies within the two sets of signals can be selectively coupled to the input ports of signal mixing apparatus and bandpass filtering is employed to couple either the mixer sum or difference frequency to the synthesizer output terminal. In some situations, a single mixer circuit and bandpass filter is employed. In other situations in which the desired frequency range and resolution cause undesired frequency components of the mixer signal to fall within the synthesized frequency range, mixing and filtering is effected in a number of subchannels, each of which include a mixer and filter. In su…

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