JPS547802A - Method and apparatus for communication for area surrounded by walls such as tunnel and underground market - Google Patents

Method and apparatus for communication for area surrounded by walls such as tunnel and underground market

Info

Publication number
JPS547802A
JPS547802A JP7283077A JP7283077A JPS547802A JP S547802 A JPS547802 A JP S547802A JP 7283077 A JP7283077 A JP 7283077A JP 7283077 A JP7283077 A JP 7283077A JP S547802 A JPS547802 A JP S547802A
Authority
JP
Japan
Prior art keywords
tunnel
walls
communication
area surrounded
underground market
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
JP7283077A
Other languages
Japanese (ja)
Other versions
JPS579259B2 (en
Inventor
Jiro Chiba
Tatsuo Inaba
Yoshitomo Kuwamoto
Osamu Sakano
Risaburo Sato
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
Hitachi Ltd
Yagi Antenna Co Ltd
Original Assignee
Hitachi Denshi KK
Hitachi Ltd
Yagi Antenna Co 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 Denshi KK, Hitachi Ltd, Yagi Antenna Co Ltd filed Critical Hitachi Denshi KK
Priority to JP7283077A priority Critical patent/JPS547802A/en
Publication of JPS547802A publication Critical patent/JPS547802A/en
Publication of JPS579259B2 publication Critical patent/JPS579259B2/ja
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B5/00—Near-field transmission systems, e.g. inductive or capacitive transmission systems

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Near-Field Transmission Systems (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

PURPOSE:To perform extremely effective signal or data transmission, by using a circular polarization helical antenna for the communication between opposing radio stations, in an area surrounded with walls such as a tunnel and underground street.
JP7283077A 1977-06-21 1977-06-21 Method and apparatus for communication for area surrounded by walls such as tunnel and underground market Granted JPS547802A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP7283077A JPS547802A (en) 1977-06-21 1977-06-21 Method and apparatus for communication for area surrounded by walls such as tunnel and underground market

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP7283077A JPS547802A (en) 1977-06-21 1977-06-21 Method and apparatus for communication for area surrounded by walls such as tunnel and underground market

Publications (2)

Publication Number Publication Date
JPS547802A true JPS547802A (en) 1979-01-20
JPS579259B2 JPS579259B2 (en) 1982-02-20

Family

ID=13500714

Family Applications (1)

Application Number Title Priority Date Filing Date
JP7283077A Granted JPS547802A (en) 1977-06-21 1977-06-21 Method and apparatus for communication for area surrounded by walls such as tunnel and underground market

Country Status (1)

Country Link
JP (1) JPS547802A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996020143A1 (en) * 1994-12-23 1996-07-04 Owens Corning Catalyzed asphalt binder for glass fibers

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996020143A1 (en) * 1994-12-23 1996-07-04 Owens Corning Catalyzed asphalt binder for glass fibers

Also Published As

Publication number Publication date
JPS579259B2 (en) 1982-02-20

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