Patent · US Expired

Tone detection for integrated telecommunications processing

US7003093B2 · kind B2 · utility

23Cited by
44References
36Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 23, 2001
Grant dateFeb 21, 2006
Priority date
Expiry dateSep 4, 2023

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04Q1/46
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

Disclosed is an integrated tone detection processor for discriminating between tone and voice signals and determining the tones. The tone detection processor performs Automatic Gain Control (AGC) to normalize the power of the tone or voice signal. Further, the energy of the tone or voice signals are determined at specific frequencies utilizing a Goertzel Filter process. The tone detection processor determines whether or not a tone is present, and if a tone exists, determines the type of tone. Based upon determining the two maximum energy levels of the Goertzel filtered tone, whether the tone is a single tone, dual tone, silence, or other (e.g. speech) can be discriminated. The tone can then be identified by a user-defined dictionary of tones. Based upon various ON and OFF cadence checks in combination with the use of TONE ON and TONE OFF counters, tones can be declared.

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