CA2335527A1 - Method for the communication between contactless-type data carriers and terminals - Google Patents
Method for the communication between contactless-type data carriers and terminals Download PDFInfo
- Publication number
- CA2335527A1 CA2335527A1 CA002335527A CA2335527A CA2335527A1 CA 2335527 A1 CA2335527 A1 CA 2335527A1 CA 002335527 A CA002335527 A CA 002335527A CA 2335527 A CA2335527 A CA 2335527A CA 2335527 A1 CA2335527 A1 CA 2335527A1
- Authority
- CA
- Canada
- Prior art keywords
- data transfer
- data
- terminal
- transfer rate
- distance
- 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.)
- Abandoned
Links
- 239000000969 carrier Substances 0.000 title claims abstract description 50
- 238000000034 method Methods 0.000 title claims abstract description 25
- 230000006854 communication Effects 0.000 title claims description 14
- 238000004891 communication Methods 0.000 title claims description 14
- 230000007175 bidirectional communication Effects 0.000 claims abstract description 5
- 238000012546 transfer Methods 0.000 claims description 114
- 230000008878 coupling Effects 0.000 claims description 10
- 238000010168 coupling process Methods 0.000 claims description 10
- 238000005859 coupling reaction Methods 0.000 claims description 10
- 230000001419 dependent effect Effects 0.000 claims 1
- 230000005540 biological transmission Effects 0.000 abstract description 3
- 230000033228 biological regulation Effects 0.000 description 9
- 230000000875 corresponding effect Effects 0.000 description 9
- 230000005672 electromagnetic field Effects 0.000 description 6
- 230000006978 adaptation Effects 0.000 description 3
- 239000003990 capacitor Substances 0.000 description 2
- 230000002457 bidirectional effect Effects 0.000 description 1
- 229940000425 combination drug Drugs 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
- 230000035945 sensitivity Effects 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
- H04B5/77—Near-field transmission systems, e.g. inductive or capacitive transmission systems specially adapted for specific purposes for interrogation
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
- G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
- G06K7/0008—General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L5/00—Arrangements affording multiple use of the transmission path
- H04L5/14—Two-way operation using the same type of signal, i.e. duplex
- H04L5/1438—Negotiation of transmission parameters prior to communication
- H04L5/1446—Negotiation of transmission parameters prior to communication of transmission speed
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Computer Networks & Wireless Communication (AREA)
- Quality & Reliability (AREA)
- Artificial Intelligence (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Near-Field Transmission Systems (AREA)
- Bidirectional Digital Transmission (AREA)
- Communication Control (AREA)
Abstract
The invention relates to a method for the bidirectional communication between non-contact data carriers and terminals, according to which the speed of data transmission can be modified in accordance with the distance to be bridged by the data transmission.
Description
Method for communication between contactless-type data carriers and terminals This invention relates to a method for bidirectional com-munication between contactless-type data carriers and termi-nals which are provided with devices for radiating electro-magnetic waves for nongalvanic, electromagnetic coupling with the data carriers. It also relates to a data carrier and a terminal for carrying out the method.
The devices of the terminals for radiating electromag-netic waves are coils and capacitors, resonant circuits, op-tocouplers and the like. The data carriers, which are formed as transponders, likewise have devices such as coils, capaci-tors, resonant circuits, optocouplers, for nongalvanic energy and/or data transfer so that the data carriers transfer en-ergy and/or data with the terminals, such as read/write ter-minals.
Contactless-type data carriers, for example contactless smart cards, are used for a great variety of applications, for example in the utilization of public transport systems, as electronic purses, health insurance ID cards and the like.
Since the number of smart cards carried by a person is gener-ally increasing constantly, a multifunctional data carrier is desirable which can be used for as many applications as pos-sible, preferably a single personal data carrier which can be used virtually for all services utilized by a person.
Contactless-type data carriers are classified depending on the possible data transfer distance as "close coupling"
data carriers with a data transfer distance between 0 and 2 millimeters and "remote coupling" data carriers, the latter being further classified as "proximity" data carriers with a data transfer distance up to 100 millimeters and "vicinity"
or "hands free" data carriers with a data transfer distance of more than 100 millimeters. While close coupling or proxim-ity data carriers can be used without any problem for some applications, there are other applications for which only vi-(corresponding to p. 3 of German) cinity data carriers are suitable. For example, an electroni-cally rechargeable Subway ticket can be readily designed for data transfer to the terminal according to the "touch and go"
principle, i.e. as a close coupling or proximity data car-rier, while such data carriers are unsuitable, or in any case extremely awkward, for access control systems at ski lifts, for example, since the lift card can be e.g. fastened to the clothing or the data carrier integrated into a wristwatch.
The carrier frequency for data transfer, the permissible frequency bandwidth and the transmitting energy emitted by the terminal for contactless data transfer between data car-riers and terminals are governed by regulations. For example, an ISO standard stipulates a carrier frequency of 13.56 MHz, whereby only a low given frequency bandwidth is permissible.
In order to solve the problem of different data transfer distances for multifunctional data carriers, one might con-sider increasing the emitted transmitting energy so that the vicinity data transfer distance holds for all applications.
However, the maximum transmitting energy is likewise limited officially for physiological and other reasons. Also, data protection provisions oppose a vicinity data transfer dis-tance in some applications of such a multifunctional data carrier.
WO 98/10364 discloses a method for identifying smart cards in order to let only one certain smart card from a group of similar cards communicate with a terminal. It is also known to operate terminals with lower power in economy operation (e. g. WO 98/01816).
US-A-4 41I 004 discloses, iii a transmitter connected with a plurality of receivers via a cable, performing data trans-fer at different transfer rates, i.e. using a higher data transfer rate for a receiver at a small distance from the transmitter than for a receiver at a large distance there-from.
- 2a (corresponding to p. 3a of German) The problem of the invention is to provide a method which permits one and the same data carrier to be used for applica-tions with both small and large data transfer distances.
This is obtained according to the invention by the method stated in claim 1.
According to the invention the rate of data transfer is varied in accordance with the distance of data transfer to be bridged.
The higher the data transfer distance is, the higher the transmitting energy emitted by the terminal must be. As stated above, however, the maximum permissible emitted trans-mitting energy is limited by administrative provisions. The higher the data transfer rate used, and the shorter the transaction time is thus selected for the processing opera-tion in the device, the higher the frequency bandwidth re-quired by the data transfer process is. Depending on the car-rier frequency used, however, the frequency bandwidth is also limited by corresponding regulations.
While a low data transfer rate involves a low frequency bandwidth, thus permitting high transmitting power of the terminal, i.e. a large data transfer distance, a high data transfer rate involves a considerably greater frequency band-width, so that the transmitting power and thus the data transfer distance are reduced according to the invention in order to meet the governing regulations.
That .is, according to the invention, data transfer is ef-fected at a low rate in remote coupling and in particular vi-cinity applications for example, while a high data transfer rate is provided in proximity and in particular close cou-pling applications for example.
Thus, one and the same data carrier can be used for bridging small and large data transfer distances according to the invention, while heeding the relevant limiting values for frequency bandwidth and emitted electromagnetic energy.
According to the invention, the terminals and data carri-ers are thus so designed that the data carriers for example are suitable for use as vicinity data carriers, proximity data carriers and close coupling data carriers. Therefore, a data transfer rate as high as possible adapted to the data transfer distance to be bridged can be used for the particu-lar application of the data carrier.
For carrying out the inventive method one preferably uses terminals having control means for varying their transmitting power in accordance with the data transfer rate. This at the same time permits use according to the invention of conven-tional data carriers, i.e. data carriers communicating at only one data transfer rate, without disturbing the function and while heeding the stated relevant regulations.
Further, according to the invention the data carrier is preferably designed for carrying out the inventive method so as to communicate at different data transfer rates in accor-dance with the data transfer distance. This permits use ac-cording to the invention of conventional terminals, i.e. ter-minals whose transmitting power is not controllable in accor-dance with the data transfer rate, without disturbing the function and while heeding the relevant regulations.
In other words, the inventive method providing low trans-mitting power of the terminal and thus a small data transfer distance at a high data transfer rate, and high transmitting power of the terminal and thus a large data transfer distance at a low data transfer rate, can be realized by a data car-rier communicating at different data transfer rates in accor-dance with the data transfer distance, and/or a terminal whose transmitting power is controllable in accordance with the data transfer rate.
The data transfer rate corresponding to the data transfer distance to be bridged is preferably varied by an additional communication step at the onset of data transfer.
In said additional communication step the relevant regu-lations for emitted energy, required transmission frequency band and physiological safety are heeded, whereby both inven-tive data carriers on conventional terminals can be used without disturbing the function and while heeding the stated relevant regulations, and inventive terminals in order to be able to read and write conventional data carriers without disturbing the function and while heeding the relevant regu-lations.
Said additional communication step can be constructed such that the inventive terminal emits a signal pattern to the data carriers before the onset of communication as an identification code for the data transfer rate to be se-lected. So that conventional data carriers can also be used for this terminal, said signal pattern must not be misinter-pretable by conventional data carriers so as to disturb and influence the subsequent data transfer.
Emission of such a signal pattern before the onset of communication as an identification code for the data transfer rate to be selected applies to those systems in which data carriers, after approaching the electromagnetic field radi-ated by the terminal, wait for a command from the terminal before beginning with transfer of data to the terminal.
Such a terminal used for access control at a ski lift for example thus emits a signal pattern blindly for the vicinity application, i.e. a signal pattern identifying a low data transfer rate, whereby a data carrier brought into the elec-tromagnetic field radiated by said terminal sends back to the terminal at the slow data transfer rate intended for said terminal, without the transmitting power of the terminal be-ing varied.
As are alternative to the abovementioned system there are methods wherein data carriers begin spontaneously with trans-fer of data after approaching the electromagnetic field radi-ated by the terminal. With an inventive terminal and an in-ventive data carrier which work according to the latter method, the inventive terminal can emit a signal pattern as an identification code for the data transfer rate to be se-lected for further data transfer after the inventive data carriers have spontaneously begun with data transfer at a given data transfer rate after approaching the electromag-netic field radiated by the terminal. The signal pattern used is one which cannot be misinterpreted by conventional data carriers, i.e. data carriers not capable of the inventive method, and therefore leads to no disturbance or influence of subsequent data transfer.
That is, if for example a large data transfer distance, i.e. low data transfer rate, is to be used and the data car-rier has spontaneously begun to transmit at a high data transfer rate upon approaching the electromagnetic field of - b -the terminal, it receives from the terminal for further data transfer a signal pattern giving it the command to now switch to the low data transfer rate.
The signal pattern as an identification code for the par-ticular data transfer rate can for example be amplitude-modulated according to a certain pattern. For example, a "single side band" or SSB modulation is possible, or a phase modulation.
The signal pattern as an identification code for the data transfer rate to be selected for further data transfer can also be a telegram used during the customary following commu-nication, which is transmitted to the data carriers at the data transfer rate used for further data transfer. That is, if the terminal transmits at a low data transfer rate for ex-ample, the data carriers only send back data at a low rate.
As an identification code for the data transfer rate to be selected for data transfer one can further use a corre-sponding data bit signal or corresponding protocol. The iden-tification can also be effected by a corresponding data sig-nal before the protocol.
Adaptation of data transfer rate refers according to the invention to data transfer from the terminal to the data car-rier. However, in particular if the terminal has such low re-ception sensitivity that data sent by the data carrier at a high data transfer rate can no longer be read, adaptation of data transfer rate can also refer to data transfer from the data carrier to the terminal or to both transfer directions.
Communication is effected according to the inventive method between contactless-type data carriers and contact-less-type terminals, whereby one or more data carriers de-signed as transponders, i.e. having coils and other suitable devices for data reception and data transfer, are brought into the electromagnetic field emitted by the terminal for the purpose of contactless, nongalvanic, electromagnetic cou-pling and bidirectional data transfer.
(corresponding to p.10 of German) With the use of the inventive data carrier, i.e. data carriers communicating at different data transfer rates in accordance with the data transfer distance, and with the use of the inventive terminal, i.e. a terminal which is control-lable for varying its transmitting power in accordance with the data transfer rate, the inventive method permits adapta-tion of the data transfer rate to the data transfer distance to be bridged so that the highest possible data transfer rate can be obtained at a given data transfer distance while heed-ing the relevant regulations.
The transmitting power of the terminal corresponding to the data transfer rate is varied in steps. It is possible for example to switch over the transmitting power of the terminal in only two steps, i.e. for a small, for example proximity, data transfer distance and for a large, for example vicinity, data transfer distance.
The data carrier can be designed in different ways, for example as a card, wristwatch, bracelet or key pendant.
The invention will be explained in more detail by way of example below with reference to the enclosed drawings, in which:
Fig. 1 shows a diagram rendering maximum transmitting power of the terminal as a function of frequency bandwidth, Fig. 2 shows schematically the representation of the com-bination consisting of the inventive data carrier and inven-tive terminal.
Fig. 1 shows the maximum permissible transmitting power of the terminal and the maximum permissible frequency band-width at a certain carrier frequency by curve A rendered with unbroken lines. While a low frequency bandwidth occurs at a low data transfer rate according to dashed line B and thus the maximum permissible transmitting power of the terminal, i.e. a large data transfer distance, is possible, the fre-quency bandwidth is considerably greater at a high data transfer rate according to dotted line C and thus only low _ g -transmitting power or a low data transfer distance is possi-ble.
Fig. 2 shows as le an inventive terminal, i.e. a terminal whose transmitting power is controllable in accordance with the data transfer rate, as lk a conventional terminal without such control of the transmitting power, as 2e an inventive data carrier communicating at different data transfer rates in accordance with the data transfer distance, and as 2k a conventional data carrier whose communication ability is re-stricted to a single data transfer rate. According to vari-ants A and B the inventive method can also be performed when conventional data carriers 2k communicate with inventive ter-minals (A) or conventional terminals lk with inventive data carriers (B). According to variant C using an inventive ter-minal and an inventive data carrier, the maximum possible data transfer rate can be attained both at a large data transfer distance (a) and at a small data transfer distance (b) .
The devices of the terminals for radiating electromag-netic waves are coils and capacitors, resonant circuits, op-tocouplers and the like. The data carriers, which are formed as transponders, likewise have devices such as coils, capaci-tors, resonant circuits, optocouplers, for nongalvanic energy and/or data transfer so that the data carriers transfer en-ergy and/or data with the terminals, such as read/write ter-minals.
Contactless-type data carriers, for example contactless smart cards, are used for a great variety of applications, for example in the utilization of public transport systems, as electronic purses, health insurance ID cards and the like.
Since the number of smart cards carried by a person is gener-ally increasing constantly, a multifunctional data carrier is desirable which can be used for as many applications as pos-sible, preferably a single personal data carrier which can be used virtually for all services utilized by a person.
Contactless-type data carriers are classified depending on the possible data transfer distance as "close coupling"
data carriers with a data transfer distance between 0 and 2 millimeters and "remote coupling" data carriers, the latter being further classified as "proximity" data carriers with a data transfer distance up to 100 millimeters and "vicinity"
or "hands free" data carriers with a data transfer distance of more than 100 millimeters. While close coupling or proxim-ity data carriers can be used without any problem for some applications, there are other applications for which only vi-(corresponding to p. 3 of German) cinity data carriers are suitable. For example, an electroni-cally rechargeable Subway ticket can be readily designed for data transfer to the terminal according to the "touch and go"
principle, i.e. as a close coupling or proximity data car-rier, while such data carriers are unsuitable, or in any case extremely awkward, for access control systems at ski lifts, for example, since the lift card can be e.g. fastened to the clothing or the data carrier integrated into a wristwatch.
The carrier frequency for data transfer, the permissible frequency bandwidth and the transmitting energy emitted by the terminal for contactless data transfer between data car-riers and terminals are governed by regulations. For example, an ISO standard stipulates a carrier frequency of 13.56 MHz, whereby only a low given frequency bandwidth is permissible.
In order to solve the problem of different data transfer distances for multifunctional data carriers, one might con-sider increasing the emitted transmitting energy so that the vicinity data transfer distance holds for all applications.
However, the maximum transmitting energy is likewise limited officially for physiological and other reasons. Also, data protection provisions oppose a vicinity data transfer dis-tance in some applications of such a multifunctional data carrier.
WO 98/10364 discloses a method for identifying smart cards in order to let only one certain smart card from a group of similar cards communicate with a terminal. It is also known to operate terminals with lower power in economy operation (e. g. WO 98/01816).
US-A-4 41I 004 discloses, iii a transmitter connected with a plurality of receivers via a cable, performing data trans-fer at different transfer rates, i.e. using a higher data transfer rate for a receiver at a small distance from the transmitter than for a receiver at a large distance there-from.
- 2a (corresponding to p. 3a of German) The problem of the invention is to provide a method which permits one and the same data carrier to be used for applica-tions with both small and large data transfer distances.
This is obtained according to the invention by the method stated in claim 1.
According to the invention the rate of data transfer is varied in accordance with the distance of data transfer to be bridged.
The higher the data transfer distance is, the higher the transmitting energy emitted by the terminal must be. As stated above, however, the maximum permissible emitted trans-mitting energy is limited by administrative provisions. The higher the data transfer rate used, and the shorter the transaction time is thus selected for the processing opera-tion in the device, the higher the frequency bandwidth re-quired by the data transfer process is. Depending on the car-rier frequency used, however, the frequency bandwidth is also limited by corresponding regulations.
While a low data transfer rate involves a low frequency bandwidth, thus permitting high transmitting power of the terminal, i.e. a large data transfer distance, a high data transfer rate involves a considerably greater frequency band-width, so that the transmitting power and thus the data transfer distance are reduced according to the invention in order to meet the governing regulations.
That .is, according to the invention, data transfer is ef-fected at a low rate in remote coupling and in particular vi-cinity applications for example, while a high data transfer rate is provided in proximity and in particular close cou-pling applications for example.
Thus, one and the same data carrier can be used for bridging small and large data transfer distances according to the invention, while heeding the relevant limiting values for frequency bandwidth and emitted electromagnetic energy.
According to the invention, the terminals and data carri-ers are thus so designed that the data carriers for example are suitable for use as vicinity data carriers, proximity data carriers and close coupling data carriers. Therefore, a data transfer rate as high as possible adapted to the data transfer distance to be bridged can be used for the particu-lar application of the data carrier.
For carrying out the inventive method one preferably uses terminals having control means for varying their transmitting power in accordance with the data transfer rate. This at the same time permits use according to the invention of conven-tional data carriers, i.e. data carriers communicating at only one data transfer rate, without disturbing the function and while heeding the stated relevant regulations.
Further, according to the invention the data carrier is preferably designed for carrying out the inventive method so as to communicate at different data transfer rates in accor-dance with the data transfer distance. This permits use ac-cording to the invention of conventional terminals, i.e. ter-minals whose transmitting power is not controllable in accor-dance with the data transfer rate, without disturbing the function and while heeding the relevant regulations.
In other words, the inventive method providing low trans-mitting power of the terminal and thus a small data transfer distance at a high data transfer rate, and high transmitting power of the terminal and thus a large data transfer distance at a low data transfer rate, can be realized by a data car-rier communicating at different data transfer rates in accor-dance with the data transfer distance, and/or a terminal whose transmitting power is controllable in accordance with the data transfer rate.
The data transfer rate corresponding to the data transfer distance to be bridged is preferably varied by an additional communication step at the onset of data transfer.
In said additional communication step the relevant regu-lations for emitted energy, required transmission frequency band and physiological safety are heeded, whereby both inven-tive data carriers on conventional terminals can be used without disturbing the function and while heeding the stated relevant regulations, and inventive terminals in order to be able to read and write conventional data carriers without disturbing the function and while heeding the relevant regu-lations.
Said additional communication step can be constructed such that the inventive terminal emits a signal pattern to the data carriers before the onset of communication as an identification code for the data transfer rate to be se-lected. So that conventional data carriers can also be used for this terminal, said signal pattern must not be misinter-pretable by conventional data carriers so as to disturb and influence the subsequent data transfer.
Emission of such a signal pattern before the onset of communication as an identification code for the data transfer rate to be selected applies to those systems in which data carriers, after approaching the electromagnetic field radi-ated by the terminal, wait for a command from the terminal before beginning with transfer of data to the terminal.
Such a terminal used for access control at a ski lift for example thus emits a signal pattern blindly for the vicinity application, i.e. a signal pattern identifying a low data transfer rate, whereby a data carrier brought into the elec-tromagnetic field radiated by said terminal sends back to the terminal at the slow data transfer rate intended for said terminal, without the transmitting power of the terminal be-ing varied.
As are alternative to the abovementioned system there are methods wherein data carriers begin spontaneously with trans-fer of data after approaching the electromagnetic field radi-ated by the terminal. With an inventive terminal and an in-ventive data carrier which work according to the latter method, the inventive terminal can emit a signal pattern as an identification code for the data transfer rate to be se-lected for further data transfer after the inventive data carriers have spontaneously begun with data transfer at a given data transfer rate after approaching the electromag-netic field radiated by the terminal. The signal pattern used is one which cannot be misinterpreted by conventional data carriers, i.e. data carriers not capable of the inventive method, and therefore leads to no disturbance or influence of subsequent data transfer.
That is, if for example a large data transfer distance, i.e. low data transfer rate, is to be used and the data car-rier has spontaneously begun to transmit at a high data transfer rate upon approaching the electromagnetic field of - b -the terminal, it receives from the terminal for further data transfer a signal pattern giving it the command to now switch to the low data transfer rate.
The signal pattern as an identification code for the par-ticular data transfer rate can for example be amplitude-modulated according to a certain pattern. For example, a "single side band" or SSB modulation is possible, or a phase modulation.
The signal pattern as an identification code for the data transfer rate to be selected for further data transfer can also be a telegram used during the customary following commu-nication, which is transmitted to the data carriers at the data transfer rate used for further data transfer. That is, if the terminal transmits at a low data transfer rate for ex-ample, the data carriers only send back data at a low rate.
As an identification code for the data transfer rate to be selected for data transfer one can further use a corre-sponding data bit signal or corresponding protocol. The iden-tification can also be effected by a corresponding data sig-nal before the protocol.
Adaptation of data transfer rate refers according to the invention to data transfer from the terminal to the data car-rier. However, in particular if the terminal has such low re-ception sensitivity that data sent by the data carrier at a high data transfer rate can no longer be read, adaptation of data transfer rate can also refer to data transfer from the data carrier to the terminal or to both transfer directions.
Communication is effected according to the inventive method between contactless-type data carriers and contact-less-type terminals, whereby one or more data carriers de-signed as transponders, i.e. having coils and other suitable devices for data reception and data transfer, are brought into the electromagnetic field emitted by the terminal for the purpose of contactless, nongalvanic, electromagnetic cou-pling and bidirectional data transfer.
(corresponding to p.10 of German) With the use of the inventive data carrier, i.e. data carriers communicating at different data transfer rates in accordance with the data transfer distance, and with the use of the inventive terminal, i.e. a terminal which is control-lable for varying its transmitting power in accordance with the data transfer rate, the inventive method permits adapta-tion of the data transfer rate to the data transfer distance to be bridged so that the highest possible data transfer rate can be obtained at a given data transfer distance while heed-ing the relevant regulations.
The transmitting power of the terminal corresponding to the data transfer rate is varied in steps. It is possible for example to switch over the transmitting power of the terminal in only two steps, i.e. for a small, for example proximity, data transfer distance and for a large, for example vicinity, data transfer distance.
The data carrier can be designed in different ways, for example as a card, wristwatch, bracelet or key pendant.
The invention will be explained in more detail by way of example below with reference to the enclosed drawings, in which:
Fig. 1 shows a diagram rendering maximum transmitting power of the terminal as a function of frequency bandwidth, Fig. 2 shows schematically the representation of the com-bination consisting of the inventive data carrier and inven-tive terminal.
Fig. 1 shows the maximum permissible transmitting power of the terminal and the maximum permissible frequency band-width at a certain carrier frequency by curve A rendered with unbroken lines. While a low frequency bandwidth occurs at a low data transfer rate according to dashed line B and thus the maximum permissible transmitting power of the terminal, i.e. a large data transfer distance, is possible, the fre-quency bandwidth is considerably greater at a high data transfer rate according to dotted line C and thus only low _ g -transmitting power or a low data transfer distance is possi-ble.
Fig. 2 shows as le an inventive terminal, i.e. a terminal whose transmitting power is controllable in accordance with the data transfer rate, as lk a conventional terminal without such control of the transmitting power, as 2e an inventive data carrier communicating at different data transfer rates in accordance with the data transfer distance, and as 2k a conventional data carrier whose communication ability is re-stricted to a single data transfer rate. According to vari-ants A and B the inventive method can also be performed when conventional data carriers 2k communicate with inventive ter-minals (A) or conventional terminals lk with inventive data carriers (B). According to variant C using an inventive ter-minal and an inventive data carrier, the maximum possible data transfer rate can be attained both at a large data transfer distance (a) and at a small data transfer distance (b) .
Claims (7)
1. A method for bidirectional communication between contactless-type data carriers and terminals which are provided with devices for radiating electromagnetic waves for nongal-vanic, electromagnetic coupling with the data carriers, characterized in that the data transfer rate is fixed in accordance with the distance of data transfer to be bridged, and the transmitting power of the terminal is varied in steps in accordance with the data transfer rate.
2. A method according to claim 1, characterized in that the data transfer rate corresponding to the data transfer distance to be bridged is fixed by an additional communication step at the onset of data transfer.
3. A method according to claim 2, characterized in that the additional communication step is constructed such that the terminal emits a signal pattern before the onset of communication as an identification code for the particular data transfer rate.
4. A method according to claim 3, characterized in that the signal pattern as an identification code for the particular data transfer rate is amplitude- and/or phase-modulated.
5. A method according to claim 1, characterized in that the transmitting power of the terminal is varied in two steps for a small data transfer distance and a larger data transfer distance.
6. A contactless-type data carrier for bidirectional communication with terminals by the method according to any of claims 1 to 5, characterized in that the data carrier has communication ability at different data transfer rates in accordance with the data transfer distance.
7. A terminal for bidirectional communication with contactless-type data carriers by the method according to any of claims 1 to 5, characterized in that the terminal is provided, for a data transfer rate dependent on the data transfer distance, with control means for varying its transmitting power in steps in accordance with the data transfer rate.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19827691.5 | 1998-06-22 | ||
| DE19827691A DE19827691C1 (en) | 1998-06-22 | 1998-06-22 | Method for communication between contactless data carriers and end devices |
| PCT/EP1999/001932 WO1999067734A1 (en) | 1998-06-22 | 1999-03-22 | Method for the communication between non-contact data carriers and terminals |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2335527A1 true CA2335527A1 (en) | 1999-12-29 |
Family
ID=7871606
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002335527A Abandoned CA2335527A1 (en) | 1998-06-22 | 1999-03-22 | Method for the communication between contactless-type data carriers and terminals |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP1090370B1 (en) |
| JP (1) | JP4414093B2 (en) |
| AT (1) | ATE223090T1 (en) |
| CA (1) | CA2335527A1 (en) |
| DE (2) | DE19827691C1 (en) |
| WO (1) | WO1999067734A1 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6963270B1 (en) | 1999-10-27 | 2005-11-08 | Checkpoint Systems, Inc. | Anticollision protocol with fast read request and additional schemes for reading multiple transponders in an RFID system |
| DE10004922A1 (en) * | 2000-02-04 | 2001-08-09 | Giesecke & Devrient Gmbh | Transponder for fitting to a contactless chip card receives energy from a high frequency alternating field via an antenna and voltage formed by a rectifier acting as a command variable to a clock generator with a frequency adjuster. |
| DE10338311B3 (en) * | 2003-08-13 | 2005-02-10 | Siemens Ag | Transponder for cheque card reader or trackside transponder for communication with passing train with receiver for transponder data telegram incorporating power module for inductive energy supply of signal source |
| JP4823943B2 (en) | 2007-03-06 | 2011-11-24 | 均 北吉 | Wireless tag, wireless tag reader, pulse encoding key detection circuit, and wireless tag system using them |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4411004A (en) * | 1980-06-27 | 1983-10-18 | Rolm Corporation | Inductively coupled sensing circuit and priority system |
| GB2208025B (en) * | 1985-04-10 | 1989-06-21 | Gen Electric Co Plc | Transaction system |
| JP2926660B2 (en) * | 1990-11-30 | 1999-07-28 | 富士通株式会社 | Method for calculating relative distance between originating terminal and destination terminal in mobile communication carrier system |
| JP3480746B2 (en) * | 1993-11-11 | 2003-12-22 | 株式会社東芝 | Portable electronic devices |
| JPH0962816A (en) * | 1994-10-06 | 1997-03-07 | Mitsubishi Electric Corp | Non-contact ic card and non-contact ic card system including the same |
| DE19715215C1 (en) * | 1997-04-11 | 1998-10-22 | Siemens Ag | Contactless transponder system |
| DE19726335C2 (en) * | 1997-06-20 | 2000-03-02 | Angewandte Digital Elektronik | Chip card with at least two coil arrangements for the transmission of data and / or energy |
-
1998
- 1998-06-22 DE DE19827691A patent/DE19827691C1/en not_active Revoked
-
1999
- 1999-03-22 CA CA002335527A patent/CA2335527A1/en not_active Abandoned
- 1999-03-22 AT AT99917835T patent/ATE223090T1/en active
- 1999-03-22 DE DE59902477T patent/DE59902477D1/en not_active Expired - Lifetime
- 1999-03-22 WO PCT/EP1999/001932 patent/WO1999067734A1/en active IP Right Grant
- 1999-03-22 EP EP99917835A patent/EP1090370B1/en not_active Expired - Lifetime
- 1999-03-22 JP JP2000556327A patent/JP4414093B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| EP1090370A1 (en) | 2001-04-11 |
| EP1090370B1 (en) | 2002-08-28 |
| JP2002519875A (en) | 2002-07-02 |
| ATE223090T1 (en) | 2002-09-15 |
| DE19827691C1 (en) | 2000-01-13 |
| DE59902477D1 (en) | 2002-10-02 |
| WO1999067734A1 (en) | 1999-12-29 |
| JP4414093B2 (en) | 2010-02-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0750201B1 (en) | Full duplex modulated backscatter system | |
| DE69702493T2 (en) | Encryption for a modulated reflective system | |
| US6459726B1 (en) | Backscatter interrogators, communication systems and backscatter communication methods | |
| US7703690B2 (en) | Non-contact IC apparatus and control method | |
| EP2283584B1 (en) | Radio frequency communication device and method for operating the same | |
| EP1895449B1 (en) | Data communication system, device for executing ic card function, control method for the device, and information processing terminal | |
| IL122841A0 (en) | Smart card for effecting data transfer using multiple protocols | |
| CN101334855A (en) | Non-contact electronic device | |
| EP2701314B1 (en) | Detection of load-modulated NFC signals | |
| AU2001270415A1 (en) | High sensitivity reader for passive transponders | |
| JP2001092938A (en) | Non-contact ic card and data processing method therefor | |
| EP0936571B1 (en) | IC card, reader and system | |
| CA2237657A1 (en) | Power transmission system, power transmission/communication system and reader and/or writer | |
| CN1184541A (en) | Method and device for adapting a chip card to different card terminals | |
| US20020044595A1 (en) | Method for transmitting a plurality of information symbols | |
| US6222880B1 (en) | Data transmission terminal and contactless data/power delivery method for use therewith | |
| CA2335527A1 (en) | Method for the communication between contactless-type data carriers and terminals | |
| US8773241B2 (en) | Device for the secure contactless data exchange between a reader and a card | |
| EP2171637B1 (en) | Radio frequency identification system provided for access control | |
| US10171132B1 (en) | Current-mode receivers for induction-based communication and related methods | |
| JP2012068932A (en) | Non-contact type ic card | |
| JP4203923B2 (en) | Transmission device in contactless transceiver system | |
| JPH0918381A (en) | Rfid system | |
| JP3072339B2 (en) | ID identification method and IC card in non-contact IC card system | |
| EP1485858B1 (en) | Communication station for communication with transponders and further communication stations with the aid of different protocols |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |