SE8200367L - SIGNAL expander - Google Patents

SIGNAL expander

Info

Publication number
SE8200367L
SE8200367L SE8200367A SE8200367A SE8200367L SE 8200367 L SE8200367 L SE 8200367L SE 8200367 A SE8200367 A SE 8200367A SE 8200367 A SE8200367 A SE 8200367A SE 8200367 L SE8200367 L SE 8200367L
Authority
SE
Sweden
Prior art keywords
signal
input
expander
amplifier
variable gain
Prior art date
Application number
SE8200367A
Other languages
Unknown language ( )
Swedish (sv)
Other versions
SE8200367A0 (en
Inventor
C B Dieterich
T J Christopher
G N Mehrotra
Original Assignee
Rca 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
Priority claimed from US06/229,743 external-priority patent/US4377788A/en
Priority claimed from US06/258,432 external-priority patent/US4398157A/en
Application filed by Rca Corp filed Critical Rca Corp
Publication of SE8200367L publication Critical patent/SE8200367L/en
Publication of SE8200367A0 publication Critical patent/SE8200367A0/en

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B3/00Line transmission systems
    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03GCONTROL OF AMPLIFICATION
    • H03G7/00Volume compression or expansion in amplifiers

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Tone Control, Compression And Expansion, Limiting Amplitude (AREA)
  • Networks Using Active Elements (AREA)
  • Control Of Amplification And Gain Control (AREA)

Abstract

In a signal expander, the envelope of an input signal (S1) to be expanded is detected (30) and applied as a control signal (S3) to the gain control input (18) of a variable gain device (14) which expands the input signal. The control signal is applied to the variable gain device via an adaptive filter (40) having improved ripple reduction and transient performance characteristics to minimize audibility of gain changes. The adaptive filter includes a low pass filter (50,52) for producing a smoothed control signal essentially free of ripple and an analog gate (70,74,78) for coupling the greater of the smoothed signal or a further signal to the variable gain device, the further signal being equal to the detector output signal less a constant. Compression of an input signal is provided by applying the input signal to the non-inverting input (110) fig 3 not shown of an amplifier (100) and feeding the (compressed) output signal (S1) of the amplifier to the expander (30,40, 14) and feeding the output signal (S2) of the expander to the inverting input of the amplifier (100). <IMAGE>
SE8200367A 1981-01-29 1982-01-22 Signal Expansion Device SE8200367A0 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US22951881A 1981-01-29 1981-01-29
US06/229,743 US4377788A (en) 1981-01-29 1981-01-29 Signal expander
US06/258,432 US4398157A (en) 1981-01-29 1981-04-28 Signal expander/compressor with adaptive control circuit

Publications (2)

Publication Number Publication Date
SE8200367L true SE8200367L (en) 1982-07-30
SE8200367A0 SE8200367A0 (en) 1982-07-30

Family

ID=27397963

Family Applications (1)

Application Number Title Priority Date Filing Date
SE8200367A SE8200367A0 (en) 1981-01-29 1982-01-22 Signal Expansion Device

Country Status (11)

Country Link
KR (1) KR830009703A (en)
AU (1) AU544439B2 (en)
DE (1) DE3202951C2 (en)
DK (1) DK38682A (en)
ES (1) ES508964A0 (en)
FR (1) FR2498850A1 (en)
GB (1) GB2094594B (en)
IT (1) IT1140449B (en)
NL (1) NL8200321A (en)
PT (1) PT74105B (en)
SE (1) SE8200367A0 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8701365D0 (en) * 1987-01-22 1987-02-25 Thomas L D Signal level control
SE9801235L (en) * 1998-04-08 1999-10-09 Anders Gingsjoe Device and method for reducing transients
DE10122922A1 (en) * 2001-05-11 2002-11-14 Mgp Instr Gmbh Measured data fluctuation suppression comprises feeding signals into filter, subtracting output signal from control signal, and feeding difference signal to comparator

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1044004A (en) * 1962-06-07 1966-09-28 Emi Ltd Improvements in or relating to circuits for compressing or expanding the amplitude range of an input signal
US3732371A (en) * 1971-05-10 1973-05-08 Richard S Burwen Wide dynamic range noise masking compandor
DE2306152A1 (en) * 1973-02-08 1974-08-15 Grundig Emv AUTOMATIC GAIN CONTROL
US3980964A (en) * 1974-05-20 1976-09-14 Grodinsky Robert M Noise reduction circuit
US4024463A (en) * 1976-05-03 1977-05-17 Rockwell International Corporation A.C. amplifier automatic gain control fast attack circuit
DE2803751C2 (en) * 1978-01-28 1982-06-09 Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt Circuit for automatic dynamic compression or expansion
US4220929A (en) * 1978-12-26 1980-09-02 Dbx, Inc. Signal expander
GB2040616B (en) * 1979-01-17 1983-01-26 Racal Dana Instr Ltd Electrical circuit arrangements

Also Published As

Publication number Publication date
AU7975882A (en) 1982-08-05
DK38682A (en) 1982-07-30
GB2094594B (en) 1984-10-24
PT74105A (en) 1982-01-01
AU544439B2 (en) 1985-05-30
GB2094594A (en) 1982-09-15
KR830009703A (en) 1983-12-22
ES8308457A1 (en) 1983-06-16
SE8200367A0 (en) 1982-07-30
IT8125956A0 (en) 1981-12-31
ES508964A0 (en) 1983-06-16
IT1140449B (en) 1986-09-24
PT74105B (en) 1983-06-15
DE3202951C2 (en) 1984-08-09
FR2498850A1 (en) 1982-07-30
NL8200321A (en) 1982-08-16
DE3202951A1 (en) 1982-08-26

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