Patent · US Expired

Method and system for detecting and classifying the modulation of unknown analog and digital telecommunications signals

US7428270B1 · kind B1 · utility

71Cited by
14References
24Claims
0Family size

Inventors

Key dates

Filing dateFeb 15, 2000
Grant dateSep 23, 2008
Priority date
Expiry dateFeb 15, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L27/0012
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Disclosed is a unique system and method for recognizing the type of modulation embedded in an unknown complex baseband signal, comprising a receiver section for extracting the complex baseband signal from a modulated signal having a carrier frequency, and comprising an orderly series of signal processing functions for (a) estimating the bandwidth of the unknown signal, (b) removing the out-of-band noise and correcting gross carrier frequency errors, (c) discriminating between constant envelope and irregular envelope signals, (d) estimating and correcting residual carrier frequency errors, (e) classifying a constant envelope signal into one of the following modulation formats: {Continuous Wave (CW), Frequency Modulation (FM), Frequency Shift Keying (FSK)}, and (f) classifying an irregular envelope signal into one of the following modulation formats: {Amplitude Modulation (AM), Double Sideband Suppressed Carrier (DSB-SC), Binary Shift Keying (BPSK), Quaternary Phase Shift Keying (QPSK), π/4-shifted QPSK, M-ary PSK (MPSK), and OTHER classes}.

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