JPS57115033A - Data transmission and reception device - Google Patents

Data transmission and reception device

Info

Publication number
JPS57115033A
JPS57115033A JP109081A JP109081A JPS57115033A JP S57115033 A JPS57115033 A JP S57115033A JP 109081 A JP109081 A JP 109081A JP 109081 A JP109081 A JP 109081A JP S57115033 A JPS57115033 A JP S57115033A
Authority
JP
Japan
Prior art keywords
noise
data signal
signal
cable
level
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
JP109081A
Other languages
Japanese (ja)
Inventor
Toshio Kimura
Kazuhiro Kiyokawa
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 Service Engineering Co Ltd
Hitachi Ltd
Original Assignee
Hitachi Service Engineering Co Ltd
Hitachi Ltd
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 Service Engineering Co Ltd, Hitachi Ltd filed Critical Hitachi Service Engineering Co Ltd
Priority to JP109081A priority Critical patent/JPS57115033A/en
Publication of JPS57115033A publication Critical patent/JPS57115033A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/02—Details
    • H04B3/04—Control of transmission; Equalising
    • H04B3/10—Control of transmission; Equalising by pilot signal
    • H04B3/11—Control of transmission; Equalising by pilot signal using pilot wire

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Detection And Prevention Of Errors In Transmission (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
  • Noise Elimination (AREA)

Abstract

PURPOSE:To enable stable communication with less error rate even on a communication line of high noise, by cancelling noise superimposed on a data signal through the use of noise signal induced in a noise detection cable and controlling the data signal level and the reception signal level against noise signal level. CONSTITUTION:A data signal from a transmitter 2 is appied to a variable gain amplifier 11 and controlled according to the noise signal level induced in a noise detection cable 16 and applied to a communication cable 9 via a transformer 4. The received data signal is applied to a noise separator 21, the noise signal is subtracted and applied to a variable attenuator 19. The data signal is attenuated with a variable attenuator 19 according to the level of noise signal from the cable 16 and applied to a receiver 7.
JP109081A 1981-01-09 1981-01-09 Data transmission and reception device Pending JPS57115033A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP109081A JPS57115033A (en) 1981-01-09 1981-01-09 Data transmission and reception device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP109081A JPS57115033A (en) 1981-01-09 1981-01-09 Data transmission and reception device

Publications (1)

Publication Number Publication Date
JPS57115033A true JPS57115033A (en) 1982-07-17

Family

ID=11491797

Family Applications (1)

Application Number Title Priority Date Filing Date
JP109081A Pending JPS57115033A (en) 1981-01-09 1981-01-09 Data transmission and reception device

Country Status (1)

Country Link
JP (1) JPS57115033A (en)

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