JPS5690634A - Automatic equalization system of photodetector - Google Patents

Automatic equalization system of photodetector

Info

Publication number
JPS5690634A
JPS5690634A JP16761779A JP16761779A JPS5690634A JP S5690634 A JPS5690634 A JP S5690634A JP 16761779 A JP16761779 A JP 16761779A JP 16761779 A JP16761779 A JP 16761779A JP S5690634 A JPS5690634 A JP S5690634A
Authority
JP
Japan
Prior art keywords
equalization
equalizer
threshold level
comparator
inter
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.)
Granted
Application number
JP16761779A
Other languages
Japanese (ja)
Other versions
JPS6221419B2 (en
Inventor
Akira Miyauchi
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.)
Fujitsu Ltd
Original Assignee
Fujitsu 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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP16761779A priority Critical patent/JPS5690634A/en
Publication of JPS5690634A publication Critical patent/JPS5690634A/en
Publication of JPS6221419B2 publication Critical patent/JPS6221419B2/ja
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/60—Receivers
    • H04B10/66—Non-coherent receivers, e.g. using direct detection
    • H04B10/69—Electrical arrangements in the receiver
    • H04B10/697—Arrangements for reducing noise and distortion
    • H04B10/6971—Arrangements for reducing noise and distortion using equalisation

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Dc Digital Transmission (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
  • Optical Communication System (AREA)

Abstract

PURPOSE:To perform equalization substantially close to perfect equalization by detecting fluctuations of the inter-code interference amount of an equalization output signal, and by widening and narrowing the frequency band of an equalizer corresponding to the detected fluctuations while increasing and decreasing the threshold level of a comparator. CONSTITUTION:The level of an equalization output signal from equalizer 13 for light signal P passed through a light transmission line is compared 14 with a threshold level to reproduce codes 1 and 0 discriminately, thereby outputting reproduced data Dout. At this time, inter-code interference amount extracting circuit 15 detects fluctuations of the amount of inter-code interference included in the equalization output signal and through frequency band characteristic control circuit 16, the frequency band of equalizer 13 is widened and narrowed corresponding to the amount of interference. Through threshold level control circuit 17, the threshold level of comparator 14 is varied. Thus, an increase in code error rate which can not be suppressed by equalizer 13 is canceled by comparator 14 to perform equalization substantially close to perfect equalization.
JP16761779A 1979-12-25 1979-12-25 Automatic equalization system of photodetector Granted JPS5690634A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP16761779A JPS5690634A (en) 1979-12-25 1979-12-25 Automatic equalization system of photodetector

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP16761779A JPS5690634A (en) 1979-12-25 1979-12-25 Automatic equalization system of photodetector

Publications (2)

Publication Number Publication Date
JPS5690634A true JPS5690634A (en) 1981-07-22
JPS6221419B2 JPS6221419B2 (en) 1987-05-12

Family

ID=15853096

Family Applications (1)

Application Number Title Priority Date Filing Date
JP16761779A Granted JPS5690634A (en) 1979-12-25 1979-12-25 Automatic equalization system of photodetector

Country Status (1)

Country Link
JP (1) JPS5690634A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2579045A1 (en) * 1985-03-14 1986-09-19 Bull Sa OPTOELECTRONIC TRANSDUCER
EP1056229A2 (en) * 1999-05-25 2000-11-29 KDD Submarine Cable Systems Inc. Optical receiving apparatus and method
JP2010536210A (en) * 2007-08-06 2010-11-25 シーメンス アクチエンゲゼルシヤフト Data transmission system and method for transmitting data in a data transmission system

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2579045A1 (en) * 1985-03-14 1986-09-19 Bull Sa OPTOELECTRONIC TRANSDUCER
EP1056229A2 (en) * 1999-05-25 2000-11-29 KDD Submarine Cable Systems Inc. Optical receiving apparatus and method
EP1056229A3 (en) * 1999-05-25 2001-09-26 KDD Submarine Cable Systems Inc. Optical receiving apparatus and method
US6856771B2 (en) 1999-05-25 2005-02-15 Kdd Submarine Cable Systems, Inc. Optical receiving apparatus and method
US7088927B2 (en) 1999-05-25 2006-08-08 Kddi Corporation Optical receiving apparatus and method
JP2010536210A (en) * 2007-08-06 2010-11-25 シーメンス アクチエンゲゼルシヤフト Data transmission system and method for transmitting data in a data transmission system
US9184836B2 (en) 2007-08-06 2015-11-10 Siemens Aktiengesellscaft Data transmission system and method for transmitting data in a data transmission system

Also Published As

Publication number Publication date
JPS6221419B2 (en) 1987-05-12

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