Patent · US Expired

Polar leapfrog filter

US5293086A · kind A · utility

2Cited by
4References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 26, 1992
Grant dateMar 8, 1994
Priority date
Expiry dateMar 26, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03H11/045
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A polar leapfrog filter includes at least one polar network. The polar network comprises a differentiator constituted by an operational amplifier having input and output terminals, and a first integrator formed by a first capacitor for providing negative feedback to the operational amplifier and a first variable transconductance amplifier; and a second integrator formed by a second capacitor for providing negative feedback to the first integrator, and a second variable transconductance amplifier. An integrator is provided at each of the input and output stages, and a third integrator is provided immediately preceding the output side integrator. In the case where two or more said polar networks are incorporated, an additional integrator is provided between the polar networks. The total number of all the circuits is selected to be even and equal to the order of the filter. The adjacent ones of the circuits are connected in such a manner that leapfrog type negative feedback is effected, and only the input side integrator is constructed in the form of self negative feedback type.

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