GB499317A - Improvements in or relating to electric wave signalling systems - Google Patents
Improvements in or relating to electric wave signalling systemsInfo
- Publication number
- GB499317A GB499317A GB2014637A GB2014637A GB499317A GB 499317 A GB499317 A GB 499317A GB 2014637 A GB2014637 A GB 2014637A GB 2014637 A GB2014637 A GB 2014637A GB 499317 A GB499317 A GB 499317A
- Authority
- GB
- United Kingdom
- Prior art keywords
- band
- signals
- lower side
- relating
- frequencies
- 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
- 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
- H04B1/62—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 providing a predistortion of the signal in the transmitter and corresponding correction in the receiver, e.g. for improving the signal/noise ratio
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Absorbent Articles And Supports Therefor (AREA)
- Materials For Medical Uses (AREA)
Abstract
499,317. Transmission systems; television. STANDARD TELEPHONES & CABLES, Ltd., HODGSON, K. G., and ROSEWAY, W. N. July 21, 1937, No. 20146. [Class 40 (iv)] [Also in Group XL] In a line transmission system using a wide band of frequencies, as for television, the level of the high frequencies is increased relatively to that of the low frequencies at the sending end and the relationship is restored at the receiving end by the use of inverse or conjugate networks, which are such that their combined effect produces no distortion of phase and attenuation. As shown, the signals (0-2 megacycles) modulate a carrier (7À5 mc.) in a modulator 2, and the lower side-band (5À5- 7À5 me.) is selected by a filter 4 and passes through the distorting network 5, which may be of the form shown in Fig. 2a. The signals then modulate a second carrier (5 mc.) in a modulator 6 and the lower side-band (0À5- 2À5 mc.) is selected. At the receiving end, the signals are applied to a demodulator 12 (5 mc.) and the upper side-band (5À5-7À5 mc.) is selected by a filter 14 and passes through the restoring network 15, which may be of the form shown in Fig. 2b. The signals are then rectified and the lower side-band is selected.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB2014637A GB499317A (en) | 1937-07-21 | 1937-07-21 | Improvements in or relating to electric wave signalling systems |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB2014637A GB499317A (en) | 1937-07-21 | 1937-07-21 | Improvements in or relating to electric wave signalling systems |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB499317A true GB499317A (en) | 1939-01-23 |
Family
ID=10141130
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB2014637A Expired GB499317A (en) | 1937-07-21 | 1937-07-21 | Improvements in or relating to electric wave signalling systems |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB499317A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2495412A1 (en) * | 1980-12-02 | 1982-06-04 | Thomson Csf | DIRECTLY MODULATED INFORMATION TRANSMISSION SYSTEM FOR OPTICALLY BANDWIDTH OPTICALLY LINKED LIGHT EXTENDED TO LOW FREQUENCIES AND CONTINUOUS |
-
1937
- 1937-07-21 GB GB2014637A patent/GB499317A/en not_active Expired
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2495412A1 (en) * | 1980-12-02 | 1982-06-04 | Thomson Csf | DIRECTLY MODULATED INFORMATION TRANSMISSION SYSTEM FOR OPTICALLY BANDWIDTH OPTICALLY LINKED LIGHT EXTENDED TO LOW FREQUENCIES AND CONTINUOUS |
| EP0053545A1 (en) * | 1980-12-02 | 1982-06-09 | Thomson-Csf | Information transmission system, using direct light-modulation, optical-link and a bandwidth extended towards low frequencies and direct current |
| US4443890A (en) * | 1980-12-02 | 1984-04-17 | Thomson-Csf | Optical-connection direct-light modulation information transmission system with a passband extended towards the low frequencies and continuous waves |
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