GB1598553A - Data transmission systems - Google Patents
Data transmission systems Download PDFInfo
- Publication number
- GB1598553A GB1598553A GB1284777A GB1284777A GB1598553A GB 1598553 A GB1598553 A GB 1598553A GB 1284777 A GB1284777 A GB 1284777A GB 1284777 A GB1284777 A GB 1284777A GB 1598553 A GB1598553 A GB 1598553A
- Authority
- GB
- United Kingdom
- Prior art keywords
- communication channel
- storage capacitor
- data source
- information signals
- switching means
- 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
- 230000005540 biological transmission Effects 0.000 title claims description 26
- 239000003990 capacitor Substances 0.000 claims description 101
- 238000001514 detection method Methods 0.000 claims description 19
- 230000003252 repetitive effect Effects 0.000 claims description 13
- 238000007599 discharging Methods 0.000 claims description 10
- 230000001939 inductive effect Effects 0.000 claims description 8
- 230000005764 inhibitory process Effects 0.000 claims description 4
- 230000000063 preceeding effect Effects 0.000 claims description 2
- 108091006146 Channels Proteins 0.000 description 67
- 230000035945 sensitivity Effects 0.000 description 2
- 108091005462 Cation channels Proteins 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Arrangements For Transmission Of Measured Signals (AREA)
Description
(54) IMPROVEMENTS RELATING TO DATA TRANSMISSION
SYSTEMS
(71) We, FERRANTI LIMITED, a Company registered under the Laws of Great
Britain of Hollinwood in the County of Lancaster do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:
This invention relates to data transmission systems, and in particular to such systems in each of which an electrical supply is to cause the transmission of information signals from at least one data source, and is connected to the data source by the same communication channel as the information signals are transmitted from the source to data receiving means.
It is an object of the present invention to provide such a data transmission system with simple and reliable means of ensuring that the electrical supply is connected to the communi-.
cation channel, and the information signals are transmitted from the data source to the receiving means over the communication channel, each exclusively in separate parts ofeach ofrepetitive time periods.
According to the present invention a data transmission system having an electrical supply, and data receiving means, both connected by way of a single communication channel to at least one data source, includes between the end of the channel adjacent to the data source, and the data source, a storage capacitor to be charged by the electrical supply, and to be discharged to cause the data source to transmit information signals to the communication channel, and there is also provided within the system switching means arranged to control at least the connection of the electrical supply to the communication channel, so that the electrical energy is not supplied to the communication channel, and to the storage capacitor, when the capacitor is discharging, and the information signals are being transmitted over the communication channel to the data receiving means, the switching means including control means to control the actuation of the switching means in a required predetermined manner, the electrical energy being supplied, and the information signals being transmitted, over the communication channel in each of repetitive time periods, in each time period the storage capacitor being charged and discharged exclusively in two separate portions of the time period, and the arrangement being such that the information signals are not transmitted from the data source whilst the storage capacitor is charging in the corresponding portion of the time period.
The data source may be caused to transmit information signals to the communication channel by the discharge of the storage capacitor energising and/or actuating transmission means associated with the data source, and/or energising, and/or actuating, the data source, where appropriate.
It is required that the duration of the portion of the time period in which electrical energy is transmitted over the communication channel is such that a sufficient amount of electrical energy is stored in the storage capacitor, at least at a voltage above a desired minimum value, to ensure the satisfactory operation of the data transmission system under all normally-encountered conditions.
In addition, it is required that the duration of the portion of the time period is which information signals are transmitted over the communication channel is such that the required information signals are wholly transmitted under all normally-encountered operating conditions.
Further, the switching means may be arranged to control the connection of the data receiving means to the communication channel.
The switching means may be in two parts, the arrangement being such that one part of the switching means is to control the connection of the electrical supply, and possibly also the connection of the data receiving means, to the communication channel; and the other part of the switching means is to control the connection of the storage capacitor and/or the transmission of the information signals from the data source, to the communication channel.
The inhibition of the transmission of information signals from the data source whilst the storage capacitor is charging may be ensured in any convenient way, and may be by the switching means.
When the switching means is in two parts, the actuation of the switching means may be controlled by control means in one or two parts. If the actuation of the switching means is controlled by two control means parts, different parts of the control means to control individually the actuation of the different parts of the switching means, the two control means parts may have different forms.
The part of the control means connected to the data source end of the communication may comprise detection means arranged to detect when the charge stored in the storage capacitor is at predetermined upper and/ or lower thresh hold values, where appropriate. The detection means may include a smaller capacitor than the storage capacitor, the smaller capacitor being shunted with a resistor, and arranged to be charged and discharged with the storage capacitor, the switching means being actuated in response to the detection of the appropriate voltage on the smaller capacitor, and proportional to the instantaneous voltage on the storage capacitor.The smaller capacitor is employed if the storage capacitor required is so large that the degree of sensitivity with which the switching means is actuated would not be sifficiently great if the switching means were to be actuated in response to the detection of the voltage on the storage capacitor.
The control means, or either part of the control means, may comprise timing means, for example, comprising a re-triggerable monostable device.
The arrangement may be such that a substantially constant D.C. supply is provided from the storage capacitor, possibly even when the electrical supply is not coupled to the storage capacitor.
The electrical supply may have an A.C., output, and the storage capacitor to be charged by the electrical supply, conveniently, may comprise part of rectifying means.
When the electrical supply has an A.C., output, the communication channel may include an inductive connector, which may have two constituent parts capable of relative rotation.
A plurality of data sources may be provided, and each data source is capable of being caused to transmit information signals by discharging the storage capacitor. Multiplexing means may be provided so that the information signals are transmitted from each such data source in series. In addition, or alternatively, decoding means may be provided, so that the information signals are transmitted only from a selected data source or sources in response to coding signals supplied over the communication channel.
The present invention will now be described by way of example with reference to the accompanying drawings, in which:
Figure 1 shows a communication channel, including an indicative connector coupled, via a storage capacitor, to data sources to be caused to transmit information signals to the communication channel by the discharge of the storage capacitor, there also being provided an
A.C. electrical supply to charge the storage capacitor, and data receiving means, both to be connected to the communication channel, and
Figure 2 is of a waveform (a) representing both the A.C. supply to charge the storage capacitor, and the information signals from the data sources, transmitted over the communication channel; and of a waveform (b) representing the corresponding repetitive charging and discharging voltage on the storage capacitor.
As shown in Figure 1 a communication channel 10 includes an inductive connector, the two parts of which connector are indicated schematically at 11 and 12. The part 11 is fixed, and the part 12 rotates relative thereto.
A plurality of data sources, for example, digital transducers, and associated multiplexing means, are indicated generally at 13. A storage capacitor C is coupled to the communication channel 10 via a part 14 of switching means, and the storage capacitor C is to be charged by electrical energy supplied over the communication channel 10 from the output of an A.C. supply 15. The output of the A.C. supply 15, which has a frequency of 20 KiloHertz, is coupled to the communication channel 10, via a portion 16' of another part 16 of the switching means.
The storage capacitor C, by discharging causes information signals to be transmitted from the transducers, in serial form, and via a lead 17, to the communication channel 10. The information signals are supplied over the communication channel, and via a portion 16" of the part 16 of the switching means, to data receiving means 18. The switching portion 16" is ganged to the other portion 16' of the switching means part 6. The switching means 14, 16 is actuated in response to control means in an appropriate manner, the control means being included within the switching means.
The manner of operation of the data transmission system is such that when the A.C.
supply 15 is charging the storage capacitor C, via the switching means parts 14 and 16, the transducers are not transmitting information signals. Further, the switching means part 14 includes a control means part comprising detection means to detect when the charge stored in the storage capacitor is at a predetermined upper threshold value, Upon the storage capacitor being charged to this state, in response to a signal from the detection means, which signal is transmitted over the communication channel, the switching means 14 and 16 is actuated so that both the A.C. supply 15 and the storage capacitor C are disconnected from the communication channel, and the data receiving means 18 is connected to the communication channel. The storage capacitor C then begins to discharge, and by this discharge the transducers are caused to transmit information signals to the data receiving means via the communication channel. After a predeter mined time, determined by timing means, comprising another control means part of either switching means part 14 or 16, and is response to a signal from the timing means, and transmitted over the communication channel, the switching means 14 and 16 is actuated again, the data receiving means is disconnected from the communication channel, the A.C. supply and the storage capacitor are re-connected to the communication channel, and the storage capacitor begins to re-charge. In consequence information signals are not transmitted from the transducers. This sequence of steps are then repeated in a repetititive way.
Each data source may be caused to transmit information signals to the communication channel by the discharge of the storage capacitor energising and/or actuating transmission means associated with the data source, and/or energising, and/or actuating, the data source.
The inhibition of the transmission of information signals from the data source whilst the storage capacitor is charging may be ensured in any convenient way, and may be by a portion of the switching means part 14.
The waveform (a) of Figure 2 represents the format of the A.C. supply and the data signals transmitted over the communication channel, and is present at point (a) on Figure
1. The waveform (b) of Figure 2 represents the corresponding repetitive charging and discharging voltage on the storage capacitor, and is present at point (b) on Figure 1. In each repetitive time period of either waveform (a) or (b) the storage capacitor is both charged and discharged. Further, each suck time period is divided into two separate portions, the storage capacitor being charged and discharged exclusively in the separate portions.
The timing means, conveniently, comprises a retriggerable monostable device.
The detection means may comprise a voltage detector arranged to detect the voltage on the storage capacitor.
If the storage capacitor is discharged by different amounts under normally-encountered operating conditions the portions of different repetitive time periods when the A.C. supply is connected to the communication channel will vary.
The data transmission system described above may be modified in may different ways.
Whilst it is essential that the switching means should control the connection of the A.C.
supply to the communication channel in the appropriate manner, it may not be essential that the connection of the storage capacitor to the communication channel should be via the part 14 of the switching means, if the arrangement is such that the storage capacitor cannot discharge into the communication channel. Thus, if the switching means part 14 is not required to be between the transducers and the communication channel, it may be omitted.
The connection of the data receiving means to the communication channel may not be controlled by the switching means, and the data receiving means may be permanently connected to the communication channel if it is not likely to be damaged by being so coupled to the electrical supply.
The detection means may have any convenient form.
The detection means may comprise the whole of the control means, and may comprise the whole of the switching means part at the data source end of the communication channel, being arranged to detect when the charge stored in the storage capacitor is at both predetermined upper and lower threshold values, and in response actuates the switching means part at the data receiving end of the communication channel in a required predetermined manner.
Thus, the timing means is omitted. Hence, both portions of repetitive time periods may vary under normally-encountered operating conditions.
Alternatively, the detection means may detect only when the charge stored in the storage capacitor is at a predetermined lower threshold value, and controls the portion of each repetitive time period in which the information signals are transmitted. Timing means is provided to determine the portion of each repetitive time period in which the capacitor is charged.
If the storage capacitor required is so large that the degree of sensitivity with which the switching means is actuated by the detection means would not be sufficiently great if the switching means were to be actuated in response to the detection of the voltage on the storage capacitor, a smaller capacitor may be included in the detection means. The smaller capacitor is shunted with a resistor, and is arranged to be charged and discharged with the storage capacitor. The switching means is actuated in response to the detection of the appropriate voltage on the smaller capacitor, which voltage is proportional to the instantaneous voltage on the storage capacitor.
When the control means, or either control means part, comprises timing means, if not comprising a retriggerable monostable device, it may have any convenient form.
In any such arrangement it is required that information signals are not transmitted over the communication channel whilst electrical energy is being transmitted over the communication channel. The duration of the portion of each repetitive time period in which electrical energy is transmitted over the communication channel is required to be such that a sufficient amount of electrical emergy is stored in the storage capacitor, at least at a voltage above a desired minimum value, to ensure the satisfactory operation of the data transmission system under all normally-encountered conditions. Further, the duration of the portion of each repetitive time period in which the capacitor is discharging is required to be such that the required information signals are wholly transmitted under normally-encountered operating conditions.
The parts of the inductive connector may not be capable of relative rotation.
An inductive connector may not be provided in the communication channel.
The storage capacitor may comprise part of rectifying means.
The arrangement may be such that a substantially constant D.C. supply is provided from the storage capacitor, even when the A.C.
supply is not coupled to the storage capacitor.
The electrical supply may have a D.C.
output.
Coding signals may be supplied over the communication channel so that only a selected transducer or selected transducers transmit data. Thus, decoding means is provided, and this decoding means may be in addition to, or instead of, the nultiplexing means of the means indicated generally at 13.
Only one data source may be provided, and the multiplexing means, and/or the decoding means, is omitted.
The data source, or sources, provided may not be transducers. The data sources may not provide digital output signals.
WHAT WE CLAIM IS:
1. A data transmission system having an electrical supply, and data receiving means, both connected by way of a single communication channel to at least one data source, including between the end of the channel adjacent to the data source, and the data source, a storage capacitor to be charged by the electrical supply, and to be discharged to cause the data source to transmit information signals to the communication channel, and there is also provided within the system switching means arranged to control at least the connection of the electrical supply to the communication channel, so that the electrical energy is not supplied to the communication channel, and to the storage capacitor, when the capacitor is discharging, and the information signals are being transmitted over the communication channel to the data receiving means, the switching means including control means to control the actuation of the switching means in a required predetermined manner, the electrical energy being supplied, and the information signals being transmitted, over the communication channel in each of repetitive time periods, in each time period the storage capacitor being charged and discharged exclusively in two separate portions of the time period, and the arrangement being such that the information signals are not transmitted from the data source whilst the storage capacitor is charging in the corresponding portion of the time period.
2. A system as claimed in Claim 1 in which the data source is caused to transmit information signals to the communication channel by the discharge of the storage capacitor energising transmission means associated with the data source.
3. A system as claimed in Claim 1 or Claim 2 in which the data source is caused to transmit information signals to the communication channel by the discharge of the storage capacitor actuating transmission means associated with the data source.
4. A system as claimed in Claim 1 or Claim 2 or Claim 3 in which the data source is caused to transmit information signals to the communication channel by the discharge of the storage capacitor energising the data source.
5. A system as claimed in any one of the preceding claims in which the data source is caused to transmit information signals to the communication channel by the discharge of the storage capacitor actuating the data source.
6. A system as claimed in any one of the preceeding claims in which the switching means is arranged to control the connection of the data receiving means to the communication channel.
7. A system as claimed in any one of the preceding claims in which the switching means is in two parts, the arrangement being such that one part of the switching means is to control the connection of the electrical supply to the communication channel, and the other part of the switching means is to control the connection of the storage capacitor to the communication channel.
8. A system as claimed in any one of the preceding claims in which the switching means is in two parts, the arrangement being such that one part of the switching means is to control the connection of the electrical supply to the communication channel and the other part of the switching means is to control the transmission of the information signals from the data source to the communication channel.
9. A system as claimed in Claim 8 in which the switching means is arranged to cause the inhibition of the transmission of information signals from the data source whilst the storage capacitor is charging.
10. A system as claimed in Claim 7 or Claim 8 or Claim 9 in which the actuation of the switching means is controlled by control means in two parts, different parts of the control means to control individually the actuation of the different parts of the switching means.
11. A system as claimed in Claim 10 in which the part of the control means connected to the data source end of the communication channel comprises detection means arranged to detect when the charge stored in the storage capacitor is at predetermined upper and/or lower threshold values.
12. A system as claimed in Claim 11 in which the detection means includes a smaller capacitor than the storage capacitor, the
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (22)
1. A data transmission system having an electrical supply, and data receiving means, both connected by way of a single communication channel to at least one data source, including between the end of the channel adjacent to the data source, and the data source, a storage capacitor to be charged by the electrical supply, and to be discharged to cause the data source to transmit information signals to the communication channel, and there is also provided within the system switching means arranged to control at least the connection of the electrical supply to the communication channel, so that the electrical energy is not supplied to the communication channel, and to the storage capacitor, when the capacitor is discharging, and the information signals are being transmitted over the communication channel to the data receiving means, the switching means including control means to control the actuation of the switching means in a required predetermined manner, the electrical energy being supplied, and the information signals being transmitted, over the communication channel in each of repetitive time periods, in each time period the storage capacitor being charged and discharged exclusively in two separate portions of the time period, and the arrangement being such that the information signals are not transmitted from the data source whilst the storage capacitor is charging in the corresponding portion of the time period.
2. A system as claimed in Claim 1 in which the data source is caused to transmit information signals to the communication channel by the discharge of the storage capacitor energising transmission means associated with the data source.
3. A system as claimed in Claim 1 or Claim 2 in which the data source is caused to transmit information signals to the communication channel by the discharge of the storage capacitor actuating transmission means associated with the data source.
4. A system as claimed in Claim 1 or Claim 2 or Claim 3 in which the data source is caused to transmit information signals to the communication channel by the discharge of the storage capacitor energising the data source.
5. A system as claimed in any one of the preceding claims in which the data source is caused to transmit information signals to the communication channel by the discharge of the storage capacitor actuating the data source.
6. A system as claimed in any one of the preceeding claims in which the switching means is arranged to control the connection of the data receiving means to the communication channel.
7. A system as claimed in any one of the preceding claims in which the switching means is in two parts, the arrangement being such that one part of the switching means is to control the connection of the electrical supply to the communication channel, and the other part of the switching means is to control the connection of the storage capacitor to the communication channel.
8. A system as claimed in any one of the preceding claims in which the switching means is in two parts, the arrangement being such that one part of the switching means is to control the connection of the electrical supply to the communication channel and the other part of the switching means is to control the transmission of the information signals from the data source to the communication channel.
9. A system as claimed in Claim 8 in which the switching means is arranged to cause the inhibition of the transmission of information signals from the data source whilst the storage capacitor is charging.
10. A system as claimed in Claim 7 or Claim 8 or Claim 9 in which the actuation of the switching means is controlled by control means in two parts, different parts of the control means to control individually the actuation of the different parts of the switching means.
11. A system as claimed in Claim 10 in which the part of the control means connected to the data source end of the communication channel comprises detection means arranged to detect when the charge stored in the storage capacitor is at predetermined upper and/or lower threshold values.
12. A system as claimed in Claim 11 in which the detection means includes a smaller capacitor than the storage capacitor, the
smaller capacitor being shunted with a resistor, and arranged to be charged and discharged with the storage capacitor, the switching means being actuated in response to the detection of the appropriate voltage on the smaller capacitor, and proportional to the instantaneous voltage on the storage capacitor.
13. A system as claimed in any one of the preceding claims in which at least part of the control means comprises timing means.
14. A system as claimed in Claim 13 in which the timing means comprises a re-triggerable monostable device.
15. A system as claimed in any one of the preceding claims in which a substantially constant D.C. supply is provided from the storage capacitor.
16. A system as claimed in any one of the preceding claims in which the electrical supply has an A.C. output, and the storage capacitor to be charged by the electrical supply comprises part of rectifying means.
17. A system as claimed in any one of the preceding claims in which the electrical supply has an A.C. output, and the communication channel includes an inductive connector.
18. A system as claimed in Claim 17 in which the inductive connector has two consitituent parts capable of relative rotation.
19. A system as claimed in any one of the preceding claims in which a plurality of data sources are provided, and each data source is capable of being caused to transmit information signals by discharging the storage capacitor.
20. A system as claimed in Claim 19 in which multiplexing means is provided so that the information signals are transmitted from each such data source in series.
21. A system as claimed in Claim 19 or
Claim 20 in which decoding means is provided, so that the information signals are transmitted only from a selected data source or sources in response to coding signals supplied over the communication channel.
22. A data transmission system substantially as described herein with reference to the accompanying drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1284777A GB1598553A (en) | 1978-05-26 | 1978-05-26 | Data transmission systems |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1284777A GB1598553A (en) | 1978-05-26 | 1978-05-26 | Data transmission systems |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1598553A true GB1598553A (en) | 1981-09-23 |
Family
ID=10012236
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB1284777A Expired GB1598553A (en) | 1978-05-26 | 1978-05-26 | Data transmission systems |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB1598553A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0162200A1 (en) * | 1984-03-31 | 1985-11-27 | ANT Nachrichtentechnik GmbH | Wideband communication system |
| GB2164180A (en) * | 1984-09-06 | 1986-03-12 | Jones Automation Limited J | Remote monitoring apparatus |
| EP0195626A3 (en) * | 1985-03-20 | 1988-07-13 | Emi Limited | Data communications system |
| CH679196A5 (en) * | 1989-10-09 | 1991-12-31 | Camille Bauer Ag | Energy and data transmission device - using modulation of voltage pulses in DC=DC voltage converter windings |
| EP0322897A3 (en) * | 1987-12-29 | 1992-02-26 | Hitachi Chemical Co., Ltd. | Simultaneous data and electric power transmitting/receiving system |
| EP0565034A3 (en) * | 1992-04-09 | 1995-02-08 | Pittway Corp | Distributed power supply system |
| EP0822684A1 (en) * | 1996-07-31 | 1998-02-04 | Mediaflow Inc. | Remote supply system for elements connected to a network |
| WO2011110442A1 (en) * | 2010-03-09 | 2011-09-15 | Robert Bosch Gmbh | Method for feeding at least one bus subscriber |
-
1978
- 1978-05-26 GB GB1284777A patent/GB1598553A/en not_active Expired
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0162200A1 (en) * | 1984-03-31 | 1985-11-27 | ANT Nachrichtentechnik GmbH | Wideband communication system |
| GB2164180A (en) * | 1984-09-06 | 1986-03-12 | Jones Automation Limited J | Remote monitoring apparatus |
| EP0195626A3 (en) * | 1985-03-20 | 1988-07-13 | Emi Limited | Data communications system |
| US4952905A (en) * | 1985-03-20 | 1990-08-28 | Emi Limited | Data communication system |
| EP0322897A3 (en) * | 1987-12-29 | 1992-02-26 | Hitachi Chemical Co., Ltd. | Simultaneous data and electric power transmitting/receiving system |
| CH679196A5 (en) * | 1989-10-09 | 1991-12-31 | Camille Bauer Ag | Energy and data transmission device - using modulation of voltage pulses in DC=DC voltage converter windings |
| EP0565034A3 (en) * | 1992-04-09 | 1995-02-08 | Pittway Corp | Distributed power supply system |
| EP0822684A1 (en) * | 1996-07-31 | 1998-02-04 | Mediaflow Inc. | Remote supply system for elements connected to a network |
| FR2752126A1 (en) * | 1996-07-31 | 1998-02-06 | Gandar Marc | SYSTEM FOR REMOTE POWERING OF ELEMENTS CONNECTED TO A NETWORK |
| WO2011110442A1 (en) * | 2010-03-09 | 2011-09-15 | Robert Bosch Gmbh | Method for feeding at least one bus subscriber |
| US8855216B2 (en) | 2010-03-09 | 2014-10-07 | Robert Bosch Gmbh | Method for supplying at least one bus user |
| DE102010002679B4 (en) | 2010-03-09 | 2023-01-05 | Robert Bosch Gmbh | Procedure for supplying at least one bus user |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed | ||
| PCNP | Patent ceased through non-payment of renewal fee |