GB2295293A - Communication through a barrier - Google Patents
Communication through a barrier Download PDFInfo
- Publication number
- GB2295293A GB2295293A GB9423093A GB9423093A GB2295293A GB 2295293 A GB2295293 A GB 2295293A GB 9423093 A GB9423093 A GB 9423093A GB 9423093 A GB9423093 A GB 9423093A GB 2295293 A GB2295293 A GB 2295293A
- Authority
- GB
- United Kingdom
- Prior art keywords
- barrier
- magnetic field
- receiver
- sequence
- predetermined code
- 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.)
- Withdrawn
Links
- 230000004888 barrier function Effects 0.000 title claims abstract description 65
- 230000005291 magnetic effect Effects 0.000 claims abstract description 49
- 238000001208 nuclear magnetic resonance pulse sequence Methods 0.000 claims description 6
- 230000004044 response Effects 0.000 claims description 3
- 238000000034 method Methods 0.000 claims 2
- 230000005355 Hall effect Effects 0.000 description 14
- 230000007246 mechanism Effects 0.000 description 11
- 230000008901 benefit Effects 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 3
- 239000002800 charge carrier Substances 0.000 description 3
- 230000001010 compromised effect Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000004020 conductor Substances 0.000 description 2
- 230000005684 electric field Effects 0.000 description 2
- 239000003302 ferromagnetic material Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000013475 authorization Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 239000002902 ferrimagnetic material Substances 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B5/00—Near-field transmission systems, e.g. inductive or capacitive transmission systems
- H04B5/70—Near-field transmission systems, e.g. inductive or capacitive transmission systems specially adapted for specific purposes
- H04B5/73—Near-field transmission systems, e.g. inductive or capacitive transmission systems specially adapted for specific purposes for taking measurements, e.g. using sensing coils
-
- G—PHYSICS
- G07—CHECKING-DEVICES
- G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
- G07C9/00—Individual registration on entry or exit
- G07C9/00174—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys
- G07C9/00182—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated with unidirectional data transmission between data carrier and locks
-
- G—PHYSICS
- G08—SIGNALLING
- G08C—TRANSMISSION SYSTEMS FOR MEASURED VALUES, CONTROL OR SIMILAR SIGNALS
- G08C17/00—Arrangements for transmitting signals characterised by the use of a wireless electrical link
- G08C17/04—Arrangements for transmitting signals characterised by the use of a wireless electrical link using magnetically coupled devices
-
- G—PHYSICS
- G07—CHECKING-DEVICES
- G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
- G07C9/00—Individual registration on entry or exit
- G07C9/00174—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys
- G07C2009/00753—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by active electrical keys
- G07C2009/00769—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by active electrical keys with data transmission performed by wireless means
- G07C2009/00777—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by active electrical keys with data transmission performed by wireless means by induction
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Signal Processing (AREA)
- Lock And Its Accessories (AREA)
Abstract
The system comprises a transmitter 3 providing a magnetic field extending through a barrier 1 (e.g. a door). The magnetic field is sequentially modulated in accordance with a message or a code to be transmitted. A receiver 5 is positioned on the other side of the barrier 1 which detects the sequentially modulated magnetic field, so providing the communication required. By being able to communicate a code with a locking system 2, 7-9 on a reverse side of a door 1, a highly secure locking system can have a door being smooth and featureless to the outside. <IMAGE>
Description
A COMMUNICATION SYSTEM
This invention relates to a communication system and more particularly to a communication system that will provide a highly secure locking system for a door or such like.
Heretofore, when a communication link is required between two spaces separated by a barrier, it has been usual to provide a communications port within the barrier as to allow the passage of a conventional communications link through the barrier thereby linking the two respective spaces. Of course, in providing this communications port through the barrier, the integrity of the barrier may thereby be compromised by the weakness of the port compared to the rest of the barrier.
This, in turn, in a situation where the integrity of the barrier is a prime concern may necessitate the use of a specially hardened, and therefore complex and expensive, communication port built to the appropriate specification.
Considering, however, those barriers that may be locked or unlocked as desired, a number of prior art systems are known.
Those most simple of these, of course, is a conventional door with a mechanical lock. By means of the engagement of a conventional key within the lock, the lock mechanism may be actuated and the door locked or unlocked as desired. Other locking systems can, of course, be envisaged whereby the lock mechanism may be actuated by means of a number of security devices of increasing sophistication, including personal identification number input pads, magnetic card readers and biometric scanners. Further locking systems may include infra red or radio transmissions to sensors placed on the outside of the barrier in order to actuate the lock mechanism.
As far as security is concerned, that is to say the requirement that the door may be locked or unlocked only by an authorised person and that that authorised person may perform that function as and when they require (i.e. a requirement that the locking system be resistant to damage), it is clear that the systems of the prior art are deficient.
In particular, they share the common feature that the front end of the locking system is visible on the exterior of the door. This affords the would be intruder not only the luxury of ease of identification as to what type of locking system has been implemented thereby allowing a head start as to finding a means of effecting entrance, but also that a "soft" target is presented which may be attacked either by those who specifically wish to deny entry to rightful entrants or by those who engage in acts of vandalism.
Furthermore, these devices will subject to possible dirt ingress and adverse weather conditions. The locking systems using radiated messages may have their transmissions captured by eavesdropping devices whence the message may subsequently be repeated by an unauthorised device.
An aim of the present invention is to provide a communication system that will overcome the disadvantages of the prior art in providing a reliable means of communication between two spaces separated by a seamless barrier where the barrier integrity is not compromised by means of a physical connection between the spaces.
Another aim of the present invention is to provide a secure barrier locking system which will overcome the disadvantages of the prior art in providing a seamless barrier which may be locked or unlocked by means which will not compromise the integrity of the barrier, and which will not provide an external weak point at which damage would stop the system from operating.
According to the invention there is provided a communication system to allow the communication of a message through a barrier comprising a transmitter on one side of said barrier adapted to provide a magnetic field extending through said barrier sequentially modulated in accordance with said message and a receiver on the other side of said barrier adapted to detect said sequentially modulated magnetic field there provided, thereby allowing communication of said message sequence from said transmitter to said receiver through said barrier.
In this way a communication system is provided with the advantage that a message may be passed between two physical spaces separated by a seamless barrier without requiring that the barrier integrity be compromised by means of a physical communication port through the barrier.
Also according to the invention there is provided a locking system to allow the locking and unlocking of a barrier comprising a transmitter on one side of said barrier adapted to provide a magnetic field extending through said barrier modulated in accordance with a first predetermined code sequence, a receiver on the other side of said barrier adapted to detect said sequentially modulated magnetic field there provided and locking means on said other side of said barrier actuable in response to a signal from the receiver representative of a condition where said detected magnetic field modulation sequence matches a second predetermined code sequence stored in said receiver.
In this way a secure barrier locking system is provided with the advantage that a seamless barrier may be locked or unlocked from the side opposite that of the locking mechanism without providing any external points on the barrier at which the locking system may be damaged.
Preferably said transmitter comprises coder means for storing said first predetermined code sequence and providing a pulse sequence representative of said first predetermined code sequence, and a magnet driven by said pulse sequence as to provide said magnetic field sequentially modulated in accordance with said first predetermined code sequence.
In this way a transmitter is provided having the advantages of simple yet effective operation.
Further preferably said receiver comprises a magnetic field detector providing an output representative of said magnetic field there detected and decoder means storing said second predetermined code sequence and receiving said output from said magnetic field detector and being capable of comparing said detected magnetic field modulation sequence with said second predetermined code sequence and providing a signal to actuate said locking means should said respective sequences match.
In this way a receiver is provided having the advantages of simple yet effective operation.
The invention will be better understood with reference to the accompanying drawings in which
Figure 1 is a schematic diagram of a locking system according to the invention;
Figure 2 is a schematic diagram of the transmitter as shown in Figure 1; and
Figure 3 is a schematic diagram of the receiver and lock actuator as shown in
Figure 1.
If Figure 1 is consulted, the door 1 to be locked or unlocked will be seen in this example in the form of a conducting barrier such as a ferromagnetic material, for example steel. The door 1 may, however, be formed of a non-conducting barrier, for example, a non-metallic material such as wood. From the outside a smooth and featureless door 1 is all that may be seen. The means by which the door 1 is locked or unlocked is shown schematically as a bolt mechanism 2 on the inside of the conducting barrier 1 which may be engaged or disengaged from the far side of the conducting barrier 1 by means of the invention.
A transmitting unit or gun 3, the "key", is provided which will produce a pulsed magnetic field in a sequence representative of a predetermined code. The gun 3 may be powered by an optional external power supply 4.
A magnetic field sensor 5 such as a Hall effect device is then located on or within the inner surface of the conducting barrier I as to detect the magnetic field extending there through.
As is well known, a Hall effect device utilises the Hall effect to provide a measure of ambient magnetic field strength. In particular, when a current carrying conductor is placed in a magnetic field whose direction is perpendicular to the direction of current, the charge carriers experience a transverse Lorentz force F = ev x B which displaces the charge carriers until such time as this force is balanced by the force due to the electric field E produced by the non-uniform charge distribution. Thus
eE + ev x B = 0 or more conveniently
E = -RH (i x B) where i = nev and RH = 1
ne (i being the current density, n being the number of charge carriers per unit volume, v being the drift velocity and RH being the Hall coefficient).
The electric field E then results in the measured potential difference - the so called Hall voltage.
A "concentrator" (not shown) may be provided at the rear of the Hall effect device, the ferro- or ferrimagnetic material thereof drawing magnetic field lines therethrough hence increasing the magnetic flux B incident upon the Hall effect device.
As is also well known, a changing magnetic field extending within a conducting material will induce a circulating current normal to the magnetic field lines, which circulating current then induces a magnetic field orientated in opposition to the generating field in accordance with Lenz's law. Thus during the period of changing magnetic fields, the net magnetic field strength diminishes the deeper within the barrier 1 it passes. It will, of course, be further determined by such factors as the respective magnetic permeability of the relevant materials and the effective lengths of the magnetic paths.
Thus if the Hall effect device 5 could not detect the magnetic field through the full thickness of the barrier 1, a recess 6 may be formed within the conducting barrier 1 as to bring the Hall effect device 5 into an effective sensing position a given distance from the outer surface of the conducting barrier 1. It will be noticed that again, no evidence of this will be seen from the outside.
If a non-ferromagnetic material is used for the door, the same consideration will apply in that the Hall effect device 5 must still be able to sense the magnetic field.
The output from the Hall effect sensor 5 will vary as with the pulsed magnetic field and thus will reproduce the code sequence. This output is then passed to a decoding unit 7 which upon receipt of the correct code sequence from the transmitter may cause the actuator driver 8 to be activated. This actuator driver 8 may then cause the actuator 9 to be driven, for example by means of a stepper motor, hence locking or unlocking the bolt mechanism 2 as required.
Turning now to Figure 2, the transmitter gun 3 may be seen in more detail, including at its heart a coder unit 10. The gun 3 will allow the transmission, by an appropriately authorised person, of the code sequence required to lock or unlock the bolt mechanism 2. Appropriate authorisation of the user, if desired, may take the form, for example, of a personal identification number input unit (not shown) which given the correct number will allow use of the device.
Alternative means of authorising use can be envisaged including the use of "smart" chips which may be recognised by a reader device within the gun.
The correct code sequence to open the lock 2 will, of course, have been stored in the coder unit 10 prior to use. This storage of the code sequence may only take place through a secure gateway element 11 which is then linked to the decoder device 7 or a master unit (not shown) wherefrom to download the locking sequence. Either the master unit or the decoder unit 7 may be used to teach several keys 3 the same code should a number of keys 3 be required to open the same door or doors 1. The code sequence may, for example, take the form of a 64 bit binary word.
When the gun 3 is activated the coder unit 10 will emit a pulse train in accordance with the stored sequence which then passes to a magnet driver 12.
This will cause the magnet unit 13, typically a solenoid or electromagnet arrangement, to create a pulsed magnetic field by means of pulsing current through the helical winding using, for example, a pulse width of 101is with a repetition frequency of 500 pulses/sec, which if orientated correctly will extend toward and pass within the conducting barrier 1.
Turning now to Figure 3, an exemplary array of eight Hall effect sensors 14 are shown1 each providing an output to an operational amplifier 15 (shown as twin operational amplifier packages) which are then in turn connected to an eight input NOR gate 16. Of course in use as many Hall effect sensors 14 as are required could be used. The output of the NOR gate 16 is then connected to a pulse shaper 17 whose output passes to a decoder unit 18 matched as with the coder unit 10 of the gun transmitter 3.
In operation if any of the Hall effect sensors 14 detect a magnetic field, they will in due course provide a corresponding Hall voltage at their output. A sequentially pulsed magnetic field will, of course, provide a similarly pulsed
Hall voltage output sequence. The amplitude of this pulse sequence may then be amplified as required by means of the operational amplifiers 15 whose outputs, as stated before, feed to the eight input NOR gate 16.
The output of this NOR gate 16 will remain high unless any one of the inputs goes low, as for example when one of the Hall effect sensors 14 detects a magnetic field producing an output pulse will then pass through the (inverting) amplifiers 15 and bring the corresponding input of the NOR gate 16 low.
Accordingly the NOR gate 16 output will provide a pulse sequence in accordance with that detected by the Hall effect sensor 14. This then passes to a pulse shaper 17 whose function is to preserve the pulse leading edge shape and timing, cleaning up the raw waveform output of the NOR gate 16, such that when the pulse, or rather the pulse train, passes to the decoder unit 18 it may be recognised.
The decoder unit 18 will then compare the sequence it has received with the correct stored sequence and should the received sequence and the stored sequence match, then the decoder unit 18 may initiate the locking or unlocking of the lock mechanism 2 as required.
This is done by means of the decoder unit 18 causing a NOR gate pulse shaper and RF filter unit 19 to trigger a monostable oscillator 20 to activate the actuator driver 8 which will then cause the actuator 9 itself to withdraw the bolt mechanism 2 from its locked position or lock the bolt mechanism 2 into place as the case may be.
The particular lock code selected at any given time is determined by means of a selection unit 21 which will allow choice of an internally generated code set or an externally generated code set downloaded through a secure gateway 22 into the pulse shaper 17 then passing into the decoder 18 in a form that may be recogrused. Subsequently, the code is then taught to the "key" transmitter gun 3 through the secure gateway 11 as described above.
The selection between the two modes will require physical access to the decoder 18 as will the teaching of the code to the "key" 3. If the mode switch unit 21 selects an externally generated code set then the person effecting remote access will require the relevant code to operate the secure gateway 22.
A host of applications may be envisaged for a locking system according to the invention, including use wherever money is to be protected inside a box, for example, pay phones, parking meters, gaming machines or safes, or wherever the sealed nature of the container is otherwise important, for example, freight containers, vehicles, shipping or pressure vessels.
As is further clear, the receiver need not actuate a lock mechanism, but could, for example, be used to operate switch gear or control valves, etc.
In its most wide conception, it is clear that a similar system would function as a communication system with the data to be transmitted taking the place of the code sequence and the receiver capturing the transmitted data having been communicated through the barrier.
Claims (9)
1. A communication system to allow the communication of a message through a barrier comprising a transmitter on one side of said barrier adapted to provide a magnetic field extending through said barrier sequentially modulated in accordance with said message and a receiver on the other side of said barrier adapted to detect said sequentially modulated magnetic field there provided, thereby allowing communication of said message sequence from said transmitter to said receiver through said barrier.
2. A communication system as claimed in claim 1 wherein said system further comprises a predetermined task accomplishing means on said other side of said barrier capable of being actuated by said receiver in response to said message sequence communicated from said transmitter to said receiver through said barrier.
3. A method of communicating a message through a barrier comprising providing from one side of said barrier a magnetic field extending through said barrier sequentially modulated in accordance with said message and detecting on the other side of said barrier said sequentially modulated magnetic field there provided, thereby allowing communication of said message sequence from said transmitter to said receiver through said barrier.
4. A locking system to allow the locking and unlocking of a barrier comprising a transmitter on one side of said barrier adapted to provide a magnetic field extending through said barrier modulated in accordance with a first predetermined code sequence, a receiver on the other side of said barrier adapted to detect said sequentially modulated magnetic field there provided and locking means on said other side of said barrier actuable in response to a signal from the receiver representative of a condition where said detected magnetic field modulation sequence matches a second predetermined code sequence stored in said receiver.
5. A locking system as claimed in claim 4 wherein said transmitter comprises coder means for storing said first predetermined code sequence and providing a pulse sequence representative of said first predetermined code sequence, and a magnet driven by said pulse sequence as to provide said magnetic field sequentially modulated in accordance with said first predetermined code sequence.
6. A locking system as claimed in claim 4 or claim 5 wherein said receiver comprises a magnetic field detector providing an output representative of said magnetic field there detected and decoder means storing said second predetermined code sequence and receiving said output from said magnetic field detector and being capable of comparing said detected magnetic field modulation sequence with said second predetermined code sequence and providing a signal to actuate said locking means should said respective sequences match.
7. A method of locking and unlocking a barrier comprising providing from one side of said barrier a magnetic field extending through said barrier modulated in accordance with a first predetermined code sequence, detecting on the other side of said barrier said sequentially modulated magnetic field
8. A communication system substantially as hereinbefore described with reference to an as illustrated in the accompanying drawings.
9. A locking system substantially as hereinbefore described with reference to an as illustrated in the accompanying drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9423093A GB2295293A (en) | 1994-11-16 | 1994-11-16 | Communication through a barrier |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9423093A GB2295293A (en) | 1994-11-16 | 1994-11-16 | Communication through a barrier |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB9423093D0 GB9423093D0 (en) | 1995-01-04 |
| GB2295293A true GB2295293A (en) | 1996-05-22 |
Family
ID=10764470
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9423093A Withdrawn GB2295293A (en) | 1994-11-16 | 1994-11-16 | Communication through a barrier |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2295293A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2301139A (en) * | 1995-05-15 | 1996-11-27 | Michael Antoniou | Container locking arrangement |
| FR2805065A1 (en) * | 2000-02-11 | 2001-08-17 | Stella | Portable viewer type reader for integrated circuit card has card receiver and means to establish communication including exchange of identification codes with fixed terminal by inductive coupling |
| US6786530B2 (en) | 2001-12-19 | 2004-09-07 | Arvinmeritor Light Vehicle Systems (Uk) Ltd. | Latching mechanism for a vehicle |
| US20130147470A1 (en) * | 2010-04-06 | 2013-06-13 | Fmc Technologies, Inc. | Inductively interrogated passive sensor apparatus |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2016576A (en) * | 1978-03-17 | 1979-09-26 | Neiman Sa | Control device for vehicle locks |
| US4684943A (en) * | 1982-04-30 | 1987-08-04 | Nippon Soken, Inc. | Unlocking device for a vehicle lid |
| GB2202414A (en) * | 1987-03-10 | 1988-09-21 | Oxley Dev Co Ltd | Transmission of power and/or data |
| EP0496024A1 (en) * | 1991-01-25 | 1992-07-29 | Siemens Aktiengesellschaft | Method to reduce power loss in contactless data and power transmission devices and means to carry out this method |
| GB2273631A (en) * | 1992-11-25 | 1994-06-22 | Ampy Automation Digilog | Improvements relating to commodity measuring meters |
-
1994
- 1994-11-16 GB GB9423093A patent/GB2295293A/en not_active Withdrawn
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2016576A (en) * | 1978-03-17 | 1979-09-26 | Neiman Sa | Control device for vehicle locks |
| US4684943A (en) * | 1982-04-30 | 1987-08-04 | Nippon Soken, Inc. | Unlocking device for a vehicle lid |
| GB2202414A (en) * | 1987-03-10 | 1988-09-21 | Oxley Dev Co Ltd | Transmission of power and/or data |
| EP0496024A1 (en) * | 1991-01-25 | 1992-07-29 | Siemens Aktiengesellschaft | Method to reduce power loss in contactless data and power transmission devices and means to carry out this method |
| GB2273631A (en) * | 1992-11-25 | 1994-06-22 | Ampy Automation Digilog | Improvements relating to commodity measuring meters |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2301139A (en) * | 1995-05-15 | 1996-11-27 | Michael Antoniou | Container locking arrangement |
| FR2805065A1 (en) * | 2000-02-11 | 2001-08-17 | Stella | Portable viewer type reader for integrated circuit card has card receiver and means to establish communication including exchange of identification codes with fixed terminal by inductive coupling |
| US6786530B2 (en) | 2001-12-19 | 2004-09-07 | Arvinmeritor Light Vehicle Systems (Uk) Ltd. | Latching mechanism for a vehicle |
| US20130147470A1 (en) * | 2010-04-06 | 2013-06-13 | Fmc Technologies, Inc. | Inductively interrogated passive sensor apparatus |
| US9506994B2 (en) * | 2010-04-06 | 2016-11-29 | Fmc Technologies, Inc. | Inductively interrogated passive sensor apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9423093D0 (en) | 1995-01-04 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |