Patent · US Expired

Digital demodulator for phase shift keyed signals

US4190802A · kind A · utility

16Cited by
4References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 17, 1978
Grant dateFeb 26, 1980
Priority date
Expiry dateAug 17, 1998

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L27/2337
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A digital demodulator for differential phase shift keyed (DPSK) signals includes two pairs of 1-bit integrators for continuously taking the phase difference between successive DPSK bits. Each DPSK bit is subdivided into a plurality of bits, for example 15 bits. A weighted output signal having 4 bits is provided by each 1-bit integrator for each of the bits corresponding to a DPSK bit. The weighted output signals from each pair of 1-bit integrators are sine weighted and multiplied. The products are then added together for application to a comparator. The comparator compares the sum of the addition to a predetermined reference signal and provides a demodulated digital signal having a logical state dependent on whether the sum is greater or smaller than the predetermined reference signal.

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