CA1158172A - Noise reduction circuit - Google Patents

Noise reduction circuit

Info

Publication number
CA1158172A
CA1158172A CA000368692A CA368692A CA1158172A CA 1158172 A CA1158172 A CA 1158172A CA 000368692 A CA000368692 A CA 000368692A CA 368692 A CA368692 A CA 368692A CA 1158172 A CA1158172 A CA 1158172A
Authority
CA
Canada
Prior art keywords
signal
level
circuit
frequency components
gain
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
CA000368692A
Other languages
English (en)
French (fr)
Inventor
Kenzo Akagiri
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.)
Sony Corp
Original Assignee
Sony Corp
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 Sony Corp filed Critical Sony Corp
Application granted granted Critical
Publication of CA1158172A publication Critical patent/CA1158172A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03G—CONTROL OF AMPLIFICATION
    • H03G9/00—Combinations of two or more types of control, e.g. gain control and tone control
    • H03G9/02—Combinations of two or more types of control, e.g. gain control and tone control in untuned amplifiers
    • H03G9/025—Combinations of two or more types of control, e.g. gain control and tone control in untuned amplifiers frequency-dependent volume compression or expansion, e.g. multiple-band systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/06—Receivers
    • H04B1/10—Means associated with receiver for limiting or suppressing noise or interference

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Tone Control, Compression And Expansion, Limiting Amplitude (AREA)
  • Reduction Or Emphasis Of Bandwidth Of Signals (AREA)
  • Signal Processing Not Specific To The Method Of Recording And Reproducing (AREA)
  • Noise Elimination (AREA)
CA000368692A 1980-01-30 1981-01-16 Noise reduction circuit Expired CA1158172A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP985780A JPS56107648A (en) 1980-01-30 1980-01-30 Noise reduction circuit
JP9857/80 1980-01-30

Publications (1)

Publication Number Publication Date
CA1158172A true CA1158172A (en) 1983-12-06

Family

ID=11731797

Family Applications (1)

Application Number Title Priority Date Filing Date
CA000368692A Expired CA1158172A (en) 1980-01-30 1981-01-16 Noise reduction circuit

Country Status (11)

Country Link
JP (1) JPS56107648A (ja)
AT (1) AT381194B (ja)
AU (1) AU539233B2 (ja)
BE (1) BE887278A (ja)
CA (1) CA1158172A (ja)
CH (1) CH657485A5 (ja)
DE (1) DE3103237C2 (ja)
FR (1) FR2474736A1 (ja)
GB (1) GB2068197B (ja)
IT (1) IT1135216B (ja)
NL (1) NL8100412A (ja)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4490691A (en) * 1980-06-30 1984-12-25 Dolby Ray Milton Compressor-expander circuits and, circuit arrangements for modifying dynamic range, for suppressing mid-frequency modulation effects and for reducing media overload
JPH0775103B2 (ja) * 1987-05-13 1995-08-09 三菱電機株式会社 ノイズリダクシヨン回路
US5424881A (en) 1993-02-01 1995-06-13 Cirrus Logic, Inc. Synchronous read channel

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3846719A (en) * 1973-09-13 1974-11-05 Dolby Laboratories Inc Noise reduction systems
US3678416A (en) * 1971-07-26 1972-07-18 Richard S Burwen Dynamic noise filter having means for varying cutoff point
US3789143A (en) * 1971-03-29 1974-01-29 D Blackmer Compander with control signal logarithmically related to the instantaneous rms value of the input signal
FI57502C (fi) * 1971-04-06 1980-08-11 Victor Company Of Japan Kompressions- och expansionssystem
US3732371A (en) * 1971-05-10 1973-05-08 Richard S Burwen Wide dynamic range noise masking compandor
GB1438711A (en) * 1973-01-23 1976-06-09 Dolby Laboratories Inc Calibration oscillators for noise reduction systems
GB1473833A (en) * 1973-05-17 1977-05-18 Dolby Laboratories Inc Circuit for the dynamic range of a signal
US3902131A (en) * 1974-09-06 1975-08-26 Quadracast Systems Tandem audio dynamic range expander
JPS52142409A (en) * 1976-05-21 1977-11-28 Toshiba Corp Noise reduction system
JPS53121506A (en) * 1977-03-31 1978-10-24 Pioneer Electronic Corp Signal compressing and expanding device
JPS5439516A (en) * 1977-09-02 1979-03-27 Sanyo Electric Co Ltd Noise reduction unit

Also Published As

Publication number Publication date
AU539233B2 (en) 1984-09-20
DE3103237A1 (de) 1981-12-03
NL8100412A (nl) 1981-09-01
ATA35781A (de) 1986-01-15
FR2474736A1 (fr) 1981-07-31
DE3103237C2 (de) 1993-10-14
FR2474736B1 (ja) 1984-11-23
AT381194B (de) 1986-09-10
AU6635881A (en) 1981-08-06
GB2068197A (en) 1981-08-05
BE887278A (fr) 1981-05-14
CH657485A5 (de) 1986-08-29
JPS6232850B2 (ja) 1987-07-17
IT8119388A0 (it) 1981-01-28
GB2068197B (en) 1984-08-08
IT1135216B (it) 1986-08-20
JPS56107648A (en) 1981-08-26

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Legal Events

Date Code Title Description
MKEX Expiry