GB1566164A - Method and apparatus for recognising and producing separated signals from multifrequency coded input signals - Google Patents

Method and apparatus for recognising and producing separated signals from multifrequency coded input signals Download PDF

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Publication number
GB1566164A
GB1566164A GB5258577A GB5258577A GB1566164A GB 1566164 A GB1566164 A GB 1566164A GB 5258577 A GB5258577 A GB 5258577A GB 5258577 A GB5258577 A GB 5258577A GB 1566164 A GB1566164 A GB 1566164A
Authority
GB
United Kingdom
Prior art keywords
signals
signal
amplitude
magnitude
instant
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB5258577A
Other languages
English (en)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Telecom Italia SpA
Original Assignee
CSELT Centro Studi e Laboratori Telecomunicazioni SpA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by CSELT Centro Studi e Laboratori Telecomunicazioni SpA filed Critical CSELT Centro Studi e Laboratori Telecomunicazioni SpA
Publication of GB1566164A publication Critical patent/GB1566164A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q1/00—Details of selecting apparatus or arrangements
    • H04Q1/18—Electrical details
    • H04Q1/30—Signalling arrangements; Manipulation of signalling currents
    • H04Q1/44—Signalling arrangements; Manipulation of signalling currents using alternate current
    • H04Q1/444—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies
    • H04Q1/45—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling
    • H04Q1/457—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling with conversion of multifrequency signals into digital signals
    • H04Q1/4575—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling with conversion of multifrequency signals into digital signals which are transmitted in digital form
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/04—Selecting arrangements for multiplex systems for time-division multiplexing

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Data Exchanges In Wide-Area Networks (AREA)
GB5258577A 1976-12-17 1977-12-16 Method and apparatus for recognising and producing separated signals from multifrequency coded input signals Expired GB1566164A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT7000776A IT1072242B (it) 1976-12-17 1976-12-17 Procedimento e dispositivo per il riconoscimento di segnali telefonici in codice multifrequenza convertiti in forma numerica

Publications (1)

Publication Number Publication Date
GB1566164A true GB1566164A (en) 1980-04-30

Family

ID=11313285

Family Applications (1)

Application Number Title Priority Date Filing Date
GB5258577A Expired GB1566164A (en) 1976-12-17 1977-12-16 Method and apparatus for recognising and producing separated signals from multifrequency coded input signals

Country Status (11)

Country Link
JP (1) JPS53121408A (US07494231-20090224-C00006.png)
AR (1) AR216659A1 (US07494231-20090224-C00006.png)
AU (1) AU507727B2 (US07494231-20090224-C00006.png)
BR (1) BR7707827A (US07494231-20090224-C00006.png)
DE (1) DE2756251C3 (US07494231-20090224-C00006.png)
FR (1) FR2374808A1 (US07494231-20090224-C00006.png)
GB (1) GB1566164A (US07494231-20090224-C00006.png)
IT (1) IT1072242B (US07494231-20090224-C00006.png)
MX (1) MX144395A (US07494231-20090224-C00006.png)
SE (1) SE437102B (US07494231-20090224-C00006.png)
TR (1) TR19857A (US07494231-20090224-C00006.png)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2184582A (en) * 1985-12-20 1987-06-24 Int Standard Electric Corp Digital tone squelch detector
EP0239809A2 (en) * 1986-03-04 1987-10-07 Nec Corporation Audio frequency signal identification apparatus

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2440126A1 (fr) * 1978-10-27 1980-05-23 Materiel Telephonique Dispositif et procede de reconnaissance pour recepteur numerique de signaux multifrequences
US4227055A (en) * 1978-12-07 1980-10-07 Bell Telephone Laboratories, Incorporated Multifrequency receiver
CA1111531A (en) * 1979-02-22 1981-10-27 Jackylene K. Hood Digital signalling receiver for receiving pcm tones
NL7903346A (nl) * 1979-04-27 1980-10-29 Bell Telephone Mfg Digitaal signaleringsstelsel.
FR2479631B1 (fr) * 1980-03-28 1986-07-25 Cit Alcatel Dispositif de confirmation de signaux
FR2485843B1 (fr) * 1980-06-25 1986-11-07 Cit Alcatel Recepteur numerique de frequences
IT1148885B (it) * 1980-07-09 1986-12-03 Sits Soc It Telecom Siemens Unita' di controllo della segnalazione di tipo multifrequenza,di particolare applicazione nelle centrali telefonichedi transito di tipo numerico
US4385208A (en) * 1981-04-15 1983-05-24 Bell Telephone Laboratories, Incorporated Multifrequency receiver
DE3424327A1 (de) * 1984-07-02 1986-01-09 Philips Patentverwaltung Gmbh, 2000 Hamburg Verfahren und schaltungsanordnung zur bestimmung der einhuellenden von signalkomponenten eines mehrfrequenzcodierten wahlzeichens
CH672968A5 (US07494231-20090224-C00006.png) * 1984-11-30 1990-01-15 Autophon Ascom Ag
JPS61225929A (ja) * 1985-03-30 1986-10-07 Fujitsu Ltd デイジタルト−ンの生成方法
CA2965941C (en) * 2013-09-20 2020-01-28 Proteus Digital Health, Inc. Methods, devices and systems for receiving and decoding a signal in the presence of noise using slices and warping

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3773981A (en) * 1972-08-07 1973-11-20 Ibm Parallel tone multiplexer-receiver
CA984068A (en) * 1972-08-10 1976-02-17 Alexander D. Proudfoot Method and apparatus for detecting the presence of signal components of predetermined frequency in a multi-frequency signal
NL7316990A (nl) * 1973-12-12 1975-06-16 Philips Nv Mfc-ontvanger voor digitale signaalverwerking.
FR2295665A1 (fr) * 1974-12-18 1976-07-16 Labo Cent Telecommunicat Recepteur numerique de signaux multifrequences
DE2515769A1 (de) * 1975-04-10 1976-10-21 Standard Elektrik Lorenz Ag Frequenzselektiver signalempfaenger

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2184582A (en) * 1985-12-20 1987-06-24 Int Standard Electric Corp Digital tone squelch detector
US4783845A (en) * 1985-12-20 1988-11-08 Itt Aerospace Optical Digital tone squelch detector
GB2184582B (en) * 1985-12-20 1989-11-22 Int Standard Electric Corp Digital tone squelch detector
EP0239809A2 (en) * 1986-03-04 1987-10-07 Nec Corporation Audio frequency signal identification apparatus
EP0239809A3 (en) * 1986-03-04 1989-03-22 Nec Corporation Audio frequency signal identification apparatus

Also Published As

Publication number Publication date
FR2374808A1 (fr) 1978-07-13
MX144395A (es) 1981-10-07
DE2756251A1 (de) 1978-06-22
TR19857A (tr) 1980-03-01
FR2374808B1 (US07494231-20090224-C00006.png) 1982-03-19
IT1072242B (it) 1985-04-10
AU3132077A (en) 1979-06-14
AU507727B2 (en) 1980-02-28
DE2756251C3 (de) 1981-11-19
BR7707827A (pt) 1978-08-22
SE7714181L (sv) 1978-06-18
SE437102B (sv) 1985-02-04
JPS5731342B2 (US07494231-20090224-C00006.png) 1982-07-03
DE2756251B2 (de) 1981-03-26
JPS53121408A (en) 1978-10-23
AR216659A1 (es) 1980-01-15

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Legal Events

Date Code Title Description
PS Patent sealed
PCNP Patent ceased through non-payment of renewal fee