GB521340A - Improvements in and relating to electric communication systems - Google Patents

Improvements in and relating to electric communication systems

Info

Publication number
GB521340A
GB521340A GB2401538A GB2401538A GB521340A GB 521340 A GB521340 A GB 521340A GB 2401538 A GB2401538 A GB 2401538A GB 2401538 A GB2401538 A GB 2401538A GB 521340 A GB521340 A GB 521340A
Authority
GB
United Kingdom
Prior art keywords
groups
group
frequency
carrier
carrier channels
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.)
Expired
Application number
GB2401538A
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.)
Telephone Manufacturing Co Ltd
Original Assignee
Telephone Manufacturing 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 Telephone Manufacturing Co Ltd filed Critical Telephone Manufacturing Co Ltd
Priority to GB2401538A priority Critical patent/GB521340A/en
Publication of GB521340A publication Critical patent/GB521340A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J1/00—Frequency-division multiplex systems
    • H04J1/02—Details
    • H04J1/12—Arrangements for reducing cross-talk between channels

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Radio Relay Systems (AREA)

Abstract

521,340. Multiplex transmission. TELEPHONE MANUFACTURING CO., 'Ltd., and PADDLE, L. H. Aug. 15, 1938, No. 24015. [Class 40 (iv)] A multiplex system comprises a number of suppressed-carrier channels occupying the frequency spectrum up to 20KC. and a number of transmitted carrier channels which are divided into groups such that after the first (or only) modulation stage the highest frequency in the groups is less than twice the lowest carrier frequency in the group. As shown, the suppressed carrier channels are fed to line through amplifier GA1 and filter GF1. The transmitted carrier channels are grouped in fours and modulate carriers of 20, 24, 28 and 32 KC. respectively. Three bf these groups are then raised in frequency in further modulators GM1, GM2, GM3. The converse arrangement is used at the receiver. In a repeater arrangement Fig. 3 (not shown), the transmitted band is split into groups by filters so that in any group no harmonic of a carrier falls within the range of the group, each group being amplified separately.
GB2401538A 1938-08-15 1938-08-15 Improvements in and relating to electric communication systems Expired GB521340A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB2401538A GB521340A (en) 1938-08-15 1938-08-15 Improvements in and relating to electric communication systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2401538A GB521340A (en) 1938-08-15 1938-08-15 Improvements in and relating to electric communication systems

Publications (1)

Publication Number Publication Date
GB521340A true GB521340A (en) 1940-05-20

Family

ID=10205010

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2401538A Expired GB521340A (en) 1938-08-15 1938-08-15 Improvements in and relating to electric communication systems

Country Status (1)

Country Link
GB (1) GB521340A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2489361A (en) * 1945-05-02 1949-11-29 Hartford Nat Bank & Trust Co Multichannel carrier wave system employing multiple modulation
EP0438075A2 (en) * 1990-01-16 1991-07-24 Alcatel SEL Aktiengesellschaft Optical cable television transmission system

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2489361A (en) * 1945-05-02 1949-11-29 Hartford Nat Bank & Trust Co Multichannel carrier wave system employing multiple modulation
EP0438075A2 (en) * 1990-01-16 1991-07-24 Alcatel SEL Aktiengesellschaft Optical cable television transmission system
EP0438075A3 (en) * 1990-01-16 1992-08-05 Standard Elektrik Lorenz Aktiengesellschaft Optical cable television transmission system
US5162937A (en) * 1990-01-16 1992-11-10 Alcatel N.V. Optical cable television transmission system

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