GB1429265A - Modulator-demodulator - Google Patents
Modulator-demodulatorInfo
- Publication number
- GB1429265A GB1429265A GB1712873A GB1712873A GB1429265A GB 1429265 A GB1429265 A GB 1429265A GB 1712873 A GB1712873 A GB 1712873A GB 1712873 A GB1712873 A GB 1712873A GB 1429265 A GB1429265 A GB 1429265A
- Authority
- GB
- United Kingdom
- Prior art keywords
- comparator
- divider
- flop
- flip
- encoder
- 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
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/10—Frequency-modulated carrier systems, i.e. using frequency-shift keying
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
Abstract
1429265 Data transmission; FSK systems INTERNATIONAL STANDARD ELECTRIC CORP 10 April 1973 [11 April 1972] 17128/73 Headings H4P and H4L A F.S.K. transceiver has a combined modulator-demodulator comprising a fully integrated common circuit to perform conversion of binary coded to frequency modulated signals reversely, which circuit comprises an oscillator, a frequency divider with reset device, a code to determine the ratio of the frequencies transmitted or received, and a comparator connected to the divider and encoder. The transmitting part of a F.S.K. transceiver comprises oscillator 1, frequency divider 2, comparator 3, encoder 4, signal transmitter, e.g. teleprinter 5 and a flip-flop 6 interconnected as shown and controlled by a switch CA. The frequency divider ratio is determined by decoder 4. When the nth condition of divider 2 is identical to the output condition of encoder 4, comparator 3 delivers a pulse which resets divider 2 to one of a pair of ratios, selected by switch 8 the output from which passes through filter 7 to line. In a receiving condition zero crossings of incoming signals are detected at 31 and encoder 4 sends to comparator 3 a code corresponding to the central frequency. When coincidence occurs, comparator 3 delivers a pulse to flipflop 28 turning it on and at the following reset the condition is transferred to flip-flop 29 which stores the information until the next cycle; flip-flop 28 is reset via delay circuit 30. If the signal/noise ratio is low compensation is made by applying the output to a shift register set at the rate of zero crossings and on which a two out of three majority decision is made. The arrangement is stated to provide signals without phase discontinuity provided that binary signals occur at the end of each division cycle which may be achieved by flip-flop 6.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR7212634A FR2179531B1 (en) | 1972-04-11 | 1972-04-11 |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1429265A true GB1429265A (en) | 1976-03-24 |
Family
ID=9096659
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB1712873A Expired GB1429265A (en) | 1972-04-11 | 1973-04-10 | Modulator-demodulator |
Country Status (6)
Country | Link |
---|---|
BE (1) | BE798045A (en) |
CH (1) | CH564892A5 (en) |
DE (1) | DE2316941A1 (en) |
ES (1) | ES413549A1 (en) |
FR (1) | FR2179531B1 (en) |
GB (1) | GB1429265A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8942298B2 (en) | 2005-12-09 | 2015-01-27 | Sonitor Technologies As | Data communications |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2434526A1 (en) * | 1978-08-23 | 1980-03-21 | Telediffusion Fse | DIGITAL MODULATOR-DEMODULATOR WITH FREQUENCY DISPLACEMENT MODULATION FOR "2-WIRE" LINE |
-
1972
- 1972-04-11 FR FR7212634A patent/FR2179531B1/fr not_active Expired
-
1973
- 1973-04-04 DE DE19732316941 patent/DE2316941A1/en active Pending
- 1973-04-10 GB GB1712873A patent/GB1429265A/en not_active Expired
- 1973-04-10 CH CH514873A patent/CH564892A5/xx not_active IP Right Cessation
- 1973-04-10 ES ES413549A patent/ES413549A1/en not_active Expired
- 1973-04-11 BE BE2052674A patent/BE798045A/en unknown
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8942298B2 (en) | 2005-12-09 | 2015-01-27 | Sonitor Technologies As | Data communications |
Also Published As
Publication number | Publication date |
---|---|
FR2179531B1 (en) | 1975-10-24 |
FR2179531A1 (en) | 1973-11-23 |
BE798045A (en) | 1973-10-11 |
ES413549A1 (en) | 1976-01-16 |
DE2316941A1 (en) | 1973-10-25 |
CH564892A5 (en) | 1975-07-31 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
GB1079928A (en) | A data transmission system | |
GB1090098A (en) | Time-bandwidth reduction system | |
GB1377262A (en) | Communication systems | |
GB1347928A (en) | Pulse position modulation communication system | |
US3980824A (en) | Modulator demodulator for binary digitally encoded messages | |
GB1036316A (en) | Improvements in or relating to data transmission systems | |
GB1220879A (en) | Improvements in and relating to communication systems | |
CA1092242A (en) | Method and apparatus for digital data transmission in television receiver remote control systems | |
US4503472A (en) | Bipolar time modulated encoder/decoder system | |
GB1479028A (en) | Data transmission systems | |
GB1429265A (en) | Modulator-demodulator | |
US3632876A (en) | Binary to pulse waveform converter | |
US4019185A (en) | Phase modulation apparatus | |
GB1212340A (en) | Transmission system comprising a transmitter and a receiver for the transmission of information in a prescribed frequency band | |
GB1392546A (en) | Binary data communication apparatus | |
GB1148805A (en) | Binary code signals transmission system | |
GB642097A (en) | Improvements in or relating to signal transmission systems | |
GB1038361A (en) | Non-synchronous phase shift communication system | |
GB1381338A (en) | Signal receivers | |
US3810161A (en) | Apparatus for receiving a frequency and phase coded vehicle control signal | |
GB1193475A (en) | Improvements in or relating to Coded Information Transmission Systems | |
GB947430A (en) | Improvements in or relating to pulse-code modulation transmission systems | |
GB1013163A (en) | Binary information transmission system | |
FR2266985A1 (en) | Radio communication method for service conversations - has message and distance monitoring signal transmission in digital form | |
GB1281169A (en) | Improvements in or relating to phase modulation transmission systems |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
CSNS | Application of which complete specification have been accepted and published, but patent is not sealed |