JPS5456708A - Double transmission communication system - Google Patents

Double transmission communication system

Info

Publication number
JPS5456708A
JPS5456708A JP12393077A JP12393077A JPS5456708A JP S5456708 A JPS5456708 A JP S5456708A JP 12393077 A JP12393077 A JP 12393077A JP 12393077 A JP12393077 A JP 12393077A JP S5456708 A JPS5456708 A JP S5456708A
Authority
JP
Japan
Prior art keywords
threshold level
line
signals
repeater
transmission line
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
JP12393077A
Other languages
Japanese (ja)
Other versions
JPS5947904B2 (en
Inventor
Hisaharu Karasawa
Masaru Aoyanagi
Isao Yamaguchi
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.)
Nippon Telegraph and Telephone Corp
Original Assignee
Nippon Telegraph and Telephone 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 Nippon Telegraph and Telephone Corp filed Critical Nippon Telegraph and Telephone Corp
Priority to JP12393077A priority Critical patent/JPS5947904B2/en
Publication of JPS5456708A publication Critical patent/JPS5456708A/en
Publication of JPS5947904B2 publication Critical patent/JPS5947904B2/en
Expired 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
    • H04B1/74—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 increasing reliability, e.g. using redundant or spare channels or apparatus

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Detection And Prevention Of Errors In Transmission (AREA)
  • Dc Digital Transmission (AREA)

Abstract

PURPOSE:To dissolve the problem of phase difference occuring between the signals of both transmission lines with no occurrence of the level fluctuation, by selecting the attenuation amount of the attenuator so that the threshold level of the pulse reproduction repeater may lower and that the pulse of the auxiliary transmission line may exceed the threshold level. CONSTITUTION:Independent auxiliary transmission line 4 is connected in parallel to using transmission line 3. The signals are always transmitted in parallel to these transmission lines at the transmitting side, and the signals sent from line 3 are supplied to pulse reproduction repeater 9 featuring the automatic threshold level control function in the form of the digital signal at the receiving side. The signals sent from line 4 are supplied as the digital signals to repeater 9 via attenuator 10. In case line 3 is normal, the digital signals from line 4 are lowered less than the threshold level of the using transmission line through repeater 9. When the signals of the using transmission line are cut off, the threshold level of repeater 9 is lowered, and the attenuation amount of the attenuator is selected so that the pulse of the auxiliary transmission line may exceed the threshold level. Thus, the problem can be dissolved for the phase difference between the both transmission lines.
JP12393077A 1977-10-14 1977-10-14 Dual transmission communication method Expired JPS5947904B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP12393077A JPS5947904B2 (en) 1977-10-14 1977-10-14 Dual transmission communication method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP12393077A JPS5947904B2 (en) 1977-10-14 1977-10-14 Dual transmission communication method

Publications (2)

Publication Number Publication Date
JPS5456708A true JPS5456708A (en) 1979-05-08
JPS5947904B2 JPS5947904B2 (en) 1984-11-22

Family

ID=14872855

Family Applications (1)

Application Number Title Priority Date Filing Date
JP12393077A Expired JPS5947904B2 (en) 1977-10-14 1977-10-14 Dual transmission communication method

Country Status (1)

Country Link
JP (1) JPS5947904B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003069456A (en) * 2001-08-28 2003-03-07 Dx Antenna Co Ltd Signal changeover device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003069456A (en) * 2001-08-28 2003-03-07 Dx Antenna Co Ltd Signal changeover device

Also Published As

Publication number Publication date
JPS5947904B2 (en) 1984-11-22

Similar Documents

Publication Publication Date Title
DE3584176D1 (en) Modulator-demodulator.
JPS5456708A (en) Double transmission communication system
US2254733A (en) Control of two-way telephone systems
JPS55105454A (en) End office repeater for optical fiber data way
JPS55141834A (en) Transmission method of synchronizing signal
JPS54161814A (en) Pilot automatic gain control system
GB1153455A (en) Telecommunication Channel Control Arrangement
JPS54156407A (en) Information communication system
JPS5781762A (en) Terminal mode switching signal system for digital telephone
JPS5628530A (en) Terminal equipment in two-way data communication system having transmission signal level automatic control mechanism
JPS55100758A (en) Fault-point orientation system
JPS54162905A (en) Radiotelephony equipment
JPS5252316A (en) Terminal connection unit in two-way catv system
JPS53131706A (en) Automatic telephone exchange system
JPS5461805A (en) Error supervisory system
JPS55161462A (en) Facsimile communication system
JPS53121416A (en) Satellite communication system
JPS5489515A (en) Control signal transmission system
JPS553221A (en) Signal transmission/reception system
JPS5661854A (en) Data transmission control device
JPS53136910A (en) Initial connection system for time division multiple connecting communication system
JPS6442930A (en) Transmission power control system for satellite communication earth station
JPS57135558A (en) Digital transmission system for subscriber line
JPS57160236A (en) Multiple transmission system for vehicle
JPS5433609A (en) Order line communication system for scpc