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
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B5/00—Near-field transmission systems, e.g. inductive or capacitive transmission systems
• • 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
  • G06K7/0095—Testing the sensing arrangement, e.g. testing if a magnetic card reader, bar code reader, RFID interrogator or smart card reader functions properly
• • 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
  • G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
  • G06K7/10009—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
  • G06K7/10316—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves using at least one antenna particularly designed for interrogating the wireless record carriers
  • G06K7/10336—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves using at least one antenna particularly designed for interrogating the wireless record carriers the antenna being of the near field type, inductive coil
• • 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
  • G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
  • G06K7/10009—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
  • G06K7/10366—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves the interrogation device being adapted for miscellaneous applications
  • G06K7/10465—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves the interrogation device being adapted for miscellaneous applications the interrogation device being capable of self-diagnosis, e.g. in addition to or as part of the actual interrogation process

Definitions

• the invention relates to contactless communication techniques between a portable object and a terminal ("terminal" will be the term used in the present description to designate a data transmitter / receiver terminal capable of cooperating with portable objects).
• each user is provided with a portable object.
• This coupling is carried out by varying a magnetic field produced by an induction coil.
• the terminal includes an inductive circuit excited by an alternating signal which produces an alternating magnetic field in the surrounding space.
• the portable object in this space detects this field and modulates in return the charge of the object
• EP-A-0 565 469 in the name of the applicant, describes the manner in which such an exchange of data is carried out, and reference may be made to this document for more details, in particular concerning the management of
• the equipment which uses this technique is for the most part isolated and autonomous, that is to say far from an operator.
• the system which controls the terminal is not always capable of detecting a fault state, insofar as it is not it is not possible to differentiate a coil failure (which prevents the emission of the magnetic field in the surrounding space) from the absence of a portable object in this surrounding space (the field is well emitted, but it is not disturbed by the no portable object).
• Current equipment generally only checks that the antenna, which is generally mounted on a cover separate from the processing electronics, is properly connected, for example by an electrical continuity test on a specific terminal of the antenna connector .
• test means capable of checking the correct operation of the terminal into the data exchange system and of producing a signal in response. status, for example to a maintenance center, indicating whether the terminal is functional or not.
• another object of the invention is to allow the self-adjustment of one or more parameters for adjusting the terminal, in particular concerning the transmission circuits and the induction coil, this in order to optimally adapt this terminal to its own electromagnetic environment and possibly allow automatic readjustment of the setting in the event of a change in this environment.
• the data exchange system of the invention is of the aforementioned known type, that is to say in which a non-galvanic bidirectional communication is established by inductive coupling between a terminal forming 3
• the system comprises, associated with the terminal, a test module comprising a circuit capable of cooperating with the terminal by inductive coupling so as to emulate communication with a portable object located in said field of action, and the terminal comprises functional test means, capable of discriminating a communication with the test module, of detecting a good communication or of a defective communication with the test module and of producing a fault signal in the event of defective communication .
• the communication can in particular be established by emission of interrogation messages by the terminal, response of the portable objects to these interrogation messages, and reception of this response by the terminal; in this case, the functional test means discriminates a response received from the test module, detects the correct response or non-response of the test module to an interrogation message and produces the fault signal in non-response.
• the functional test means include measurement means capable of qualitatively evaluating, in the event response of the test module, the coupling between the terminal and the test module, as well as control means of the adjustment means, operating in response to indications given by the measuring means.
• the circuit of the test module can be structurally similar to the corresponding circuit of a portable object, in particular a circuit remotely powered by the terminal, the test module can even be structurally similar to a portable object.
• the functional test means are activated iteratively and / or inhibited in the event of detection of a response from a portable object to a terminal interrogation message, or in the event of detection of a collision between such responses .
• the discrimination operated by the functional test means can in particular be obtained by emission of an interrogation message 4
• the fault signal can be particularly used as a remote alarm signal transmitted to a remote site.
• Figure 1 is a block diagram showing, in a contactless data exchange system according to the invention, an assembly consisting of a terminal, its associated test module and a portable object located in the surrounding field.
• Figure 2 is a block diagram of the test module of the system of Figure 1.
• FIG. 3 is a flowchart showing the different stages of the automatic functional test of the system according to the invention.
• FIG. 4 is a flowchart showing the various stages of the automatic adjustment of the transmission parameters of the terminal.
• the reference 10 designates a terminal for the exchange of contactless data by induction by means of a coil 12 emitting an alternating electromagnetic field intended for portable objects or "badges" such as 14, capable of enter the space where the field of the coil 12 is radiated.
• the terminal comprises, in a manner known per se, a modulator / demodulator circuit 16 producing an alternating signal for excitation of the coil 12 and detecting the modifications of this field created by a load modulation carried out inside a portable object 14.
• the circuit 16 is connected to a central processing unit 18 ensuring in particular the management of the various communication protocols, and connected to a remote site for the purpose of reporting and sending a message of sta- 5
• test module capable of simulating the presence of a portable object in the field of the coil. 12.
• test module 20 will have a behavior (detection of the field emitted by the terminal and sending of a response) similar - except for the differences which will be indicated below - to that of a portable object. 14 which would enter this same surrounding space.
• the terminal will in this way be able to independently control its ability to interact with a portable object presented in its field, thus verifying the influence of the transmission on reception and guaranteeing the proper functioning of the terminal.
• the circuit of the test module can be structurally similar to that of a standard portable object such as 14. In this case, it is advantageous to provide a circuit remotely powered by the magnetic field generated by the terminal, the module test then being a completely isolated circuit which therefore does not require connection with the electronics of the antenna.
• the module From the point of view of the exchange of signals, the module must be at least capable of communicating in a manner analogous to portable objects from the point of view of the physical layer of the communication protocol; optionally, it may also be capable of generating, in the load modulation, signals of programmable form useful for various measurements and tests with a view to optimal automatic adjustment of the parameters of the terminal (see below).
• FIG. 2 gives an example of a block diagram of such a test module 20, the structure of which is comparable to that of a portable object such as 14.
• the test module comprises an induction coil 22 (intended to cooperate with the coil 12 of the terminal), a modulator / demodulator circuit 24, a circuit 26 for transmitting and generating signals and a circuit 28 for reception of commands sent by the terminal, capable of acting on circuit 26 to transmit to the terminal a 6
• the test module 20 also includes an energy management circuit 30 capable of producing a direct supply voltage for the various components of the module, so as to make it fully autonomous.
• an external supply for example a supply connected to the general supply of the circuits of terminal 10 (the wired connection, intended to supply the supply energy, then being the only galvanic connection between the test module and the associated terminal).
• the terminal In general, in an exchange between terminal and portable object, the terminal is the master of communication. This means that, to establish communication with a card, the terminal starts by sending an interrogation message or call message, then waits for a short time. If a portable object receives this message, it issues a response; the terminal receives this response and then continues the dialogue by sending a command to the portable object. If, on the other hand, the terminal has not received a response within a given time, it repeats the transmission of the interrogation message.
• this process is the same with the test module 20, that is to say that the terminal is the master of the communication and it is it which initiates the dialogue with the test module by sending a message d 'interrogation.
• this message includes for example a header byte at the start of the communication protocol indicating it is an interrogation message intended for a normal portable object ("broadcast condition") or, on the contrary, reserved for the sole use of the test module.
• the terminal receives a response from the test module, this means that it is functional, and the corresponding status can be sent to the maintenance center.
• the status may be accompanied by an "in service” signaling indicating to the user that he is dealing with an effectively functional terminal: an absence of reaction from the terminal to a 7
• the absence of response received from the test module indicates a functional fault, which must lead to the immediate production of a remote alarm signal to the remote site and the deactivation of the terminal, accompanied for example by a signaling "out of order".
• the response returned by the test module can always be in the same format and limited to the communication of the minimum information necessary for communication with the terminal and for monitoring the link.
• certain types of fault are likely to be poorly detected in this case, in particular when the functional test runs continuously (ten times per second) on the test module in the absence of a portable object.
• the functional test runs continuously (ten times per second) on the test module in the absence of a portable object.
• a terminal-specific RAM can temporarily store the data contained in the cards of successive travelers, the test module assuming a cal- applie on the last portable object presented in order to change its identity.
• the test module will be able to simulate continuously, not a portable object preferably determined once and for all, but a succession of "portable objects” corresponding to travelers or other users having successively appeared before the validator .
• no "sensitive" data that is to say no confidential or personal data, will be copied into this RAM (then in the EEPROM of the smart card).
• the test module only finally stops when the presence of a real user portable object is detected: - presence detection, by any means, or
• an indicator light permanently displays the words "In Service”, this indication meaning very exactly that the device was in working order less than a second previously: that is, a very low probability of technical failure during the passage of 'a user.
• the system of the invention detects the functional nature or not of the terminal, but it also allows the adaptation of the transmission / reception circuits to the own electromagnetic environment of the terminal .
• terminal 10 includes a circuit 32 for adjusting various parameters such as the transmission power of the modulator 16 and fine tuning of the resonant circuit associated with the coil 12.
• This circuit 32 ensures, in the event of a response from the test module, a qualitative evaluation of the inductive coupling between the coil 12 of the terminal and the coil 22 of the test module 20, thus making it possible to seek an optimum coupling as a function the particular situation of the terminal (we know in particular that the induction circuits are very sensitive to the surrounding metallic masses), and a possible readjustment of these settings in the event of a change in the environment.
• the test module can advantageously include, in its signal generation module 26, means for varying the response signal, for example the waveform, the duty cycle of a square signal. , etc., useful for measurement and testing.
• the test module can also, for example, vary the energy it absorbs, in particular to assess the transmission power required on the terminal side to allow satisfactory data exchange.
• FIGS 3 and 4 are flowcharts explaining in more detail the sequence of the different test steps.
• the flow diagram of FIG. 3 illustrates the detection of the functional nature or not of the terminal by the test module.
• step 100 The particular steps of the invention are incorporated into the conventional process, which includes the transmission of an interrogation message intended for a portable object, or "user card", possibly present in the field of action of the terminal (step 100).
• step 104 If such a portable object is detected, that is to say if the terminal detects a response in return (step 102), the data exchange continues with the portable object so as to process the information in the desired manner (step 104).
• the absence of response is due to the fact that no portable object is in the field of action of the terminal; exceptionally, this lack of response can however be due to a fault in the terminal's transmit / receive circuits.
• the functional test steps are implemented after the expiration of a time delay (steps 106, 108), for example of the order of one minute.
• the terminal transmits (step 110) an interrogation message intended for the test module, this interrogation message including the specific protocol (particular header byte) allowing the test module to recognize that it it is an interrogation message intended for it and preventing recognition of this interrogation message by surrounding portable objects.
• this interrogation message including the specific protocol (particular header byte) allowing the test module to recognize that it it is an interrogation message intended for it and preventing recognition of this interrogation message by surrounding portable objects.
• step 112 If the test is correct (step 112), that is to say if the terminal detects a return response from the test module, the flowchart returns to its starting point, if necessary indicating a "end of failure" in the event that, on the previous iteration, the test was not correct (steps 114, 116).
• the test is not correct, that is to say if the terminal does not receive a response or a non-conforming response (degraded signal for example), an alarm "start of failure" is given. If the previous test was not correct either, the flowchart loops over the steps 110 and 112 of execution of the test and analysis of the results of the test, until a satisfactory result is obtained; this last loop avoids any attempt to send an interrogation or processing message to a portable object until it has been remedied.
• the flow diagram of FIG. 4 illustrates the automatic and adaptive adjustment of the modulator / demodulator circuit 16 of the terminal.
• the terminal first of all addresses to the test module a command to generate a first signal of particular shape, for example a square signal of given duty cycle (step 200).
• the terminal circuit 32 then qualitatively assesses the 10 range for this particular signal (step 202) and, if the measurement obtained is not considered satisfactory, modifies one of the settings of the modulator / demodulator 16 of the terminal and of the tuned circuit associated with the coil 12 (step 204 ).
• step 206 If all the adjustment possibilities have been exhausted (step 206), this means that, despite all the possible adjustments, it is not possible to obtain a satisfactory coupling, and the reader is then considered to be non-functional (step 208). It is then immediately deactivated and corresponding status information is sent to the remote site in to require maintenance.
• the terminal repeats to the test module its command to generate the particular signal chosen (step 200), and the process thus continues until a satisfactory coupling is obtained, that is to say d 'a measurement considered to be correct in step 202.

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• 1998
  • 1998-03-18 FR FR9803321A patent/FR2776444B1/fr not_active Expired - Fee Related
• 1999
  • 1999-03-15 JP JP54663699A patent/JP2001527679A/ja active Pending
  • 1999-03-15 KR KR1019997010661A patent/KR20010012700A/ko not_active Application Discontinuation
  • 1999-03-15 AU AU28402/99A patent/AU2840299A/en not_active Abandoned
  • 1999-03-15 WO PCT/FR1999/000564 patent/WO1999048225A1/fr not_active Application Discontinuation
  • 1999-03-15 EP EP99909007A patent/EP0983639A1/de not_active Withdrawn

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