GB632778A - Improvements in telephonic transmission systems using multiple channel carrier currents - Google Patents
Improvements in telephonic transmission systems using multiple channel carrier currentsInfo
- Publication number
- GB632778A GB632778A GB11846/45A GB1184645A GB632778A GB 632778 A GB632778 A GB 632778A GB 11846/45 A GB11846/45 A GB 11846/45A GB 1184645 A GB1184645 A GB 1184645A GB 632778 A GB632778 A GB 632778A
- Authority
- GB
- United Kingdom
- Prior art keywords
- band
- frequencies
- modulated
- modulator
- filter
- 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
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J1/00—Frequency-division multiplex systems
- H04J1/02—Details
- H04J1/04—Frequency-transposition arrangements
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Time-Division Multiplex Systems (AREA)
Abstract
632,778. Multiplex systems. SUEUR, R. C. May 11, 1945, No. 11846. Convention date, Nov. 25, 1943. [Class 40 (iv)] The voice frequencies of one channel A1 and side-band frequencies obtained by modulating a carrier wave f1 with voice frequencies B1 of a second channel are transmitted together as a group. The filter F1 accepts the original frequencies (0-4 kc/s.) and F2 accepts the upper side-band (4-8 kc/s.) produced when f1 is modulated by B1 in the modulator M1. A carrier f2 is modulated by the group frequencies in a modulator M2 and the lower side-band accepted by a filter F3 is applied with five similar groups A2, B2 ... A6, B6, making twelve channels in all, to a group modulator M3, where a carrier f3 is modulated. Before amplification at A and transmission to line L, the lower band is finally selected by a filter F4. The operations are reversed at the receiver. The twelve channels occupy a band of frequencies of 48 kc/s. between 60 and 108 kc/s. In a modification, the groups are fed through an additional stage of modulation before they are assembled together in one band.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR986620T | 1943-11-25 |
Publications (1)
Publication Number | Publication Date |
---|---|
GB632778A true GB632778A (en) | 1949-12-05 |
Family
ID=9538222
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB11846/45A Expired GB632778A (en) | 1943-11-25 | 1945-05-11 | Improvements in telephonic transmission systems using multiple channel carrier currents |
Country Status (2)
Country | Link |
---|---|
FR (1) | FR986620A (en) |
GB (1) | GB632778A (en) |
-
1943
- 1943-11-25 FR FR986620D patent/FR986620A/en not_active Expired
-
1945
- 1945-05-11 GB GB11846/45A patent/GB632778A/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
FR986620A (en) | 1951-08-02 |
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