Patent · US Expired

Digital filter bank

US4131766A · kind A · utility

55Cited by
3References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 11, 1977
Grant dateDec 26, 1978
Priority date
Expiry dateJul 11, 1997

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04J4/005
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

Disclosed is a digital filter for modulating and demodulating in frequency division multiplexing systems. For modulating a number of voice channels, a Fourier transform processor computes the discrete Fourier transform of a first series of data samples representative of the number of voice channels in time division multiplex format. A weighting network weights the transformed samples with predetermined weighting coefficients to form a frequency division multiplexed signal with proper passband characteristics. For demodulating a frequency division multiplexed signal the weighting network weights the samples with predetermined weighting coefficients and the Fourier transform processor computes a discrete Fourier transform of the weighted samples to form a time division multiplexed signal representative of the number of voice channels.

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