JPS56132031A - Telephone transmission system - Google Patents

Telephone transmission system

Info

Publication number
JPS56132031A
JPS56132031A JP3391380A JP3391380A JPS56132031A JP S56132031 A JPS56132031 A JP S56132031A JP 3391380 A JP3391380 A JP 3391380A JP 3391380 A JP3391380 A JP 3391380A JP S56132031 A JPS56132031 A JP S56132031A
Authority
JP
Japan
Prior art keywords
monitor signal
amplifier
gain
level
output
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.)
Pending
Application number
JP3391380A
Other languages
Japanese (ja)
Inventor
Tetsuo Tsuji
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.)
Hitachi Denshi KK
Original Assignee
Hitachi Denshi KK
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 Hitachi Denshi KK filed Critical Hitachi Denshi KK
Priority to JP3391380A priority Critical patent/JPS56132031A/en
Publication of JPS56132031A publication Critical patent/JPS56132031A/en
Pending legal-status Critical Current

Links

Classifications

    • 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
    • H04B1/62—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 for providing a predistortion of the signal in the transmitter and corresponding correction in the receiver, e.g. for improving the signal/noise ratio
    • H04B1/64—Volume compression or expansion arrangements

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Reduction Or Emphasis Of Bandwidth Of Signals (AREA)

Abstract

PURPOSE:To prevent the occurrence of distortion, by suppressing preliminarily the sound level of the transmittable level or more in the transmission side and by suppressing the monitor signal by the same suppression quantity also to transmit it. CONSTITUTION:The voice signal inputted to terminal 1 and the monitor signal from the monitor signal oscillator are supplied to variable gain amplifier 6. If the output level at transmission-side output terminal 2 exceeds the upper limit value of transmission line, the gain of amplifier 6 is controlled by gain controller 7 to suppress the output level. At this time, the monitor signal is suppressed by the same suppression quantity also and is transmitted to the transmission line. In the receiving side, monitor signal f1 is extracted by filter 10 connected to the output of amplifier 9, and the gain of amplifier 9 is increased by the suppression quantity of monitor signal f1 by gain controller 11.
JP3391380A 1980-03-19 1980-03-19 Telephone transmission system Pending JPS56132031A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3391380A JPS56132031A (en) 1980-03-19 1980-03-19 Telephone transmission system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3391380A JPS56132031A (en) 1980-03-19 1980-03-19 Telephone transmission system

Publications (1)

Publication Number Publication Date
JPS56132031A true JPS56132031A (en) 1981-10-16

Family

ID=12399751

Family Applications (1)

Application Number Title Priority Date Filing Date
JP3391380A Pending JPS56132031A (en) 1980-03-19 1980-03-19 Telephone transmission system

Country Status (1)

Country Link
JP (1) JPS56132031A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63177636A (en) * 1987-01-19 1988-07-21 Toshiba Corp In-band tone transmitting system
JPH03132227A (en) * 1989-10-18 1991-06-05 Matsushita Electric Ind Co Ltd Rf multiple signal light transmission system

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS50122812A (en) * 1974-03-15 1975-09-26

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS50122812A (en) * 1974-03-15 1975-09-26

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63177636A (en) * 1987-01-19 1988-07-21 Toshiba Corp In-band tone transmitting system
JPH03132227A (en) * 1989-10-18 1991-06-05 Matsushita Electric Ind Co Ltd Rf multiple signal light transmission system

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