CH714449A2 - RFID transponder module for communicating information to a reading device. - Google Patents

Abstract

The transponder module (2) is placed on a moving object to transmit information in the vicinity of a reading device. The transponder module comprises at least one energy source (4) for supplying the transponder module (2), at least one sensor (5) for measuring a physical parameter, a microcontroller (22) connected to the sensor (5) to process the sensor measurements. The module further comprises a memory unit (21) for storing the measurement data of the measurements made by the sensor, a receiver of an interrogation signal of a reading device in the vicinity, and a transmitter (23) for transmitting data. measurement data stored at ultra-high frequency and at very high bit rate following the reception of an interrogation signal from the reading device in the vicinity.

Description

Description

TECHNICAL FIELD OF THE INVENTION The invention relates to an RFID transponder module, which can be passive or semi-passive, for communication of information to a reading device.

The invention also relates to an information communication system with an RFID transponder module.

The invention also relates to a method of activating the RFID transponder module for the transmission of information to a reading device.

STATE OF THE ART [0004] Usually for the transmission of information, RFID communication is used between a transponder and a reader in particular by a near field connection (NFC) or Bluetooth. The transponder, which can be passive, is first awakened by an interrogation signal from a reader, and a rectifier in the transponder makes it possible to draw from the received signal, a supply voltage for the operation of said transponder. Generally when awakened, the transponder can transmit, for example, constant information, which is an identification number of the transponder or of the product or object on which it is placed. This constant information is therefore transmitted by the transponder at the request of the RFID reader in communication.

[0005] In conventional RFID transponders, the transmission of data or constant information is done with average bit rates of the order of a few hundred kbits / s. This requires a fairly long data transmission and therefore relatively high consumption. This does not in principle allow the use only of energy taken from an external auxiliary source connected to the transponder circuit to allow sufficient power until the transmission of all the data, which is a drawback.

[0006] In the case of a connection by Bluetooth, there is first of all a synchronization carried out with the reader. It is also used a heavy communication protocol, which is complicated and heavy consumer of current. Therefore, it is not conceivable to use such communication by Bluetooth for a passive or semi-passive transponder powered by extracting energy from an external energy source, which constitutes a drawback.

[0007] A transponder or portable RFID device can be placed on a moving object or a person or an animal. The transponder may include sensors to measure different physical parameters of the object or the person or animal. These measurements can be transmitted to a reader or base station for remote use or processing of the measurements. However, the transponder or the portable RFID device must be supplied by a sufficient energy source so as to be able to transmit the measurements carried out without too high a consumption, which is difficult to achieve by a transponder or portable device of the state of the art.

We can cite patent application WO 2012/125 425 A1, which describes a portable device, in the form of a patch, provided with various sensors. This portable device can be placed on a person to determine, via several sensors, different physiological parameters of the person (biorhythms). The measurements made can be stored and transmitted to a processing station, which manages the measurements made by the portable device on the person for medical follow-up, for example. The portable device includes a battery to provide the power necessary to obtain the various measurements by the sensors. However, this portable device cannot operate without the supply battery and its consumption is not reduced so as to carry out measurements periodically and in order to be able to transmit the stored information to the processing station quickly, which constitutes a drawback.

SUMMARY OF THE INVENTION The object of the invention is therefore to provide an RFID transponder module for communication of information to a reading device overcoming the abovementioned drawbacks of the prior art, and operating at low voltage power supply to be able to periodically carry out measurements by at least one sensor and transmit them quickly when a reading device passes.

To this end, the invention relates to an RFID transponder module for information communication, which includes the features mentioned in independent claim 1.

Special forms of the RFID transponder module are defined in dependent claims 2 to 15.

An advantage of the transponder module according to the invention lies in the fact that it can be powered by energy extraction from an auxiliary energy source, in order to allow it to operate partially for carrying out measurements. by at least one sensor and preferably by a number of sensors. The transponder module can thus remain continuously supplied and carry out measurements by the sensors in order to store the results of the measurements in a memory unit with at least one volatile memory. The sensors are connected to a microcontroller, which can be clocked by a low consumption oscillator, such as an RC or ring type oscillator.

CH 714 449 A2 As soon as a communication can be established with a nearby reader, all the measurement data can be transmitted at very high speed by a transmitter activated at least from this instant and in a very short period of time . The transmitter's oscillator can be woken up upon receipt of an interrogation and / or synchronization signal from the RFID reading device to clock the measurement data transmission operations. As soon as all the stored measurement data have been transmitted, the transmitter can again be placed in a sleep mode.

To this end, the invention also relates to an information communication system, which comprises the characteristics mentioned in independent claim 16.

To this end, the invention also relates to a method of activating a transponder module in an information communication system, which comprises the characteristics mentioned in independent claim 17. [0016] Specific steps of the process are defined in dependent claims 18 and 19.

BRIEF DESCRIPTION OF THE FIGURES The aims, advantages and characteristics of an RFID transponder module for the communication of information, the communication system comprising it, and the method of activating the RFID transponder module will appear better in the following description based on at least one non-limiting embodiment illustrated by the drawings in which:

fig. 1 is a simplified view of an information communication system with at least one transponder module and one or more reading devices for the high speed communication of information from the transponder module to the nearby reading device according to the invention, and fig. 2 shows a simplified block diagram of the electronic components of the RFID transponder module with the measurement sensor (s) and the power source (s) for supplying the RFID transponder module according to the invention.

DETAILED DESCRIPTION OF THE INVENTION In the following description, the electronic components of an RFID transponder module for the communication of information to at least one reading device nearby, and of the data communication system comprising it, which are well known to a person skilled in the art in this technical field, are only described in a simplified manner.

[0019] FIG. 1 represents a data or command communication system 1. The system 1 mainly comprises at least one transponder module 2, which can be placed on a mobile object 10, such as a person or an animal, or a vehicle of any type , and one or more reading devices 3, 3 'arranged in different locations on a defined area. The locations of the reading devices 3, 3 ′ may be locations in a public place, in a dwelling, in a store, on a course in nature, in an urban area or in various other locations.

The transponder module 2, placed for example on a person or an animal 10, may be of the passive or semi-passive type. According to the embodiment shown in fig. 1, it comprises a transponder circuit 20, which can be personalized for the wearer of the transponder module 2, at least one power source 4 of the transponder circuit 20, and at least one measurement sensor 5.

The power source 4 is preferably a backup energy source, which can be a solar cell, a thermoelectric generator (TEG), which is also known as a Seebeck generator, a magnetic induction circuit, a piezoelectric element or possibly a small battery. An energy extraction from the auxiliary energy source can be carried out by the transponder circuit 20 to charge a charge accumulator so as to allow the transponder circuit 20 to be supplied with voltage. A combination of several sources can be used additional energy 4 to supply the transponder circuit.

Preferably, the transponder module 2 can include a set of sensors 5 connected to the transponder circuit 20. It can be envisaged to use different sensors 5 to measure, at least by determined time periods, physiological parameters of the person or of animal 10 (biorhythms). The sensor set 5 can include a temperature sensor, a pressure sensor, a well-meter, a magnetic sensor, an accelerometer, a gyroscope, an optical sensor or other types of sensor depending on the application. The measurements made by the sensors can be stored after sampling or analog to digital conversion at least temporarily in at least one memory as explained below with reference to FIG. 2.

With the auxiliary energy source (s) 4, most of the electronic components of the transponder circuit 20 and the sensors 5 can operate continuously, because their consumption is greatly reduced. On the other hand, when the transponder module 2 approaches a reading device 3 for example within 50 cm, this reading device 3 transmits by at least one antenna 11, an interrogation and / or synchronization signal at a carrier frequency of the order of 868 MHz, for example, to the transponder module 2. This has the effect of fully activating all the electronic components of said transponder module 2. In this fully activated state, the transponder module 2 can

CH 714 449 A2 transmit by an antenna 12, a large part of the measurement data memorized by a UHF transmitter intended for the reading device 3 in interrogation, which receives them by the antenna 11. Preferably all the measurements carried out by the sensors 5 linked to the transponder circuit 20, are transmitted at very high speed, for example at a speed of the order of 26 Mbits / s and at ultra-high frequency of the order of 5.8 GHz.

It can be seen that with very high speed and ultra high frequency transmission, all of the stored measurements from the sensors 5 can be transmitted very quickly in a very short time of less than 1 s and without requiring great electrical consumption. of said transponder module 2. Once all the measurement data have been transmitted, the transmitter of the transponder circuit 20 can enter a rest mode before a new interrogation of a reading device 3, 3 '.

Such a transponder module 2 can be used to control the biorhythms of a person or an animal 10 (moving object) where the measurements made by the sensors change continuously. A reading device 3 can be placed for example in a part of a house or in a garden or also in a cat flap if the animal is a cat, to take all the memorized measurements of the sensors in operation. As the measurements of the sensors can be carried out at low voltage and low consumption, the transponder module 2 remains continuously activated for this part of the transponder circuit 20. The transmitter of said module is still at rest before the interrogation of the reading device 3 at passage of the person or the animal, such as a cat for example in a cat flap. Each reading device 3, 3 ′ can also be connected by cable or wirelessly to a central processing unit, such as a computer, for the management of all the measurement data.

[0026] FIG. 2 shows in more detail the electronic components of the RFID transponder module 2 to better understand its operation.

The transponder module 2 generally comprises a transponder circuit 20, at least one measurement sensor 5 and preferably a set of measurement sensors 5, and one or more energy sources, which can be energy sources booster 4, whose energy can be extracted to supply the transponder circuit 20 and other parts of the transponder module 2.

Or the n sensors Capteur_1 à Capteur_n are connected to a microcontroller 22, which is preferably clocked by a low frequency clock, coming from a low consumption oscillator, such as an RC type oscillator or an oscillator in a ring. The measurements made by the sensors are digitally converted in the microcontroller to be stored in a memory unit 21 in defined positions. The converted measurement data are in principle stored in a volatile memory of the SRAM type, since this requires low storage consumption in this type of memory. However, if the supply voltage level is sufficient, it can also be envisaged to store this measurement data in a non-volatile memory such as a FLASH memory, which requires more consumption for the storage of information. Under these conditions, provision may be made to detect the level of the supply voltage in the microcontroller in order to know in which type of memory the measurement data can be stored. Below a defined voltage threshold, the measurement data can be stored in the volatile memory, while above this voltage threshold the measurement data can be stored in the non-volatile memory NVM.

As indicated above, several additional energy sources 4 can be provided, or even a small battery. Energy is extracted from these energy sources by a well-known extractor 26, which is represented in the transponder circuit 20 by a diode. An accumulator (capacitor) 27 at the output of the extractor is charged in order to allow the supply of the supply voltage for the transponder circuit 20. However, instead of the accumulator, it can also be an element to be super-capacity if the auxiliary energy source is always present, such as engine vibrations, or a permanently lit hangar for example.

The transponder module 2 also includes a receiver 25, which can be a receiver of high frequency HF signals 25 in order to receive high frequency signals Sr by a first antenna 12 'coming from a reading device 3 in interrogation. A conventional rectifier, not shown, which may be in the HF signal receiver 25, is provided for rectifying the received signals and making it possible also to supply energy for the power supply of the transponder module 2. High frequency signals can be signals with a carrier frequency greater than 400 MHz, for example 434 MHz, 868 MHz or 916 MHz with a preference for the frequency of 868 MHz. The HF receiver 25 can remain partly at rest or have certain reception parts permanently activated before conversion of the signals. These activated parts of the receiver consume very little current until a conversion of reception signals is carried out.

The transponder module 2 also includes a transmitter 23 for transmitting ultra high frequency signals St by a second antenna 12 when it is activated. This transmitter 23 is clocked by its own quartz oscillator 24, which can be at an oscillation frequency of the order of 26 MHz for example. As soon as the interrogation signals 25 are received by the receiver, the signals received by the first antenna 12 ′ can be converted in conjunction with the oscillator 24 of the transmitter 23 and a traditional frequency synthesizer.

It should also be noted that for waking up and receiving signals from the transponder module 2, the receiver 25 may be able to pick up low frequency signals of the order of 125 kHz or high frequency of the order of 13

CH 714 449 A2

MHz (NFC) or higher than 400 MHz, for example 868 MHz. A conversion of the signals is carried out on the basis of the RC oscillator of the microcontroller 22. Under these conditions, the receiver can remain permanently activated.

It can also be envisaged to wake up the transponder module 2 by any other means, such as by receiving an optical, infrared, ultrasonic or other signal.

Once the transponder module 2, carried by a mobile object, approaches a short distance from a reading device, for example as for NFC near field communication, the reading device transmits a signal d 'interrogation and / or synchronization to the transponder module 2, which detects it nearby. From this instant, the transponder module 2 can fully activate the receiver 25 and the transmitter 23 with its oscillator 24 to enable it to transmit ultra high frequency St data signals, for example at a carrier frequency above 2 GHz and preferably around 5.8 GHz. All the measurement data stored in the memory unit 21 and clocked by the RC oscillator of the microcontroller 22 are transmitted as soon as the transmitter is activated, which can transmit data at low power thanks to its proximity to the reading device. The measurement data can be modulated in phase (OQPSK) and transmitted at very high speed, for example at a speed of the order of 26 Mbits / s.

As each transponder module includes a personalized identification number, for example to the person or animal carrying it, it may be authorized to question several transponder modules near the same reading device. There is no risk of collision of the measurement data transmitted by each activated transmitter near the same reading device.

The supply voltage used for the operation of the transponder module 2 can be less than 3 V, for example of the order of 0.6 V, preferably being extracted from at least one auxiliary energy source 4 Once a communication with a reading device is carried out, the energy of the signals received in reception can be obtained by a rectifier to also ensure the electrical supply of the transponder module 2.

According to the method of actuating the RFID transponder module 2 for the transmission of information to a reading device, it is planned to carry out several measurements over time by the sensor or sensors 5 on the control of the microcontroller 22 of the transponder module 2. At least the microcontroller 22 and the sensors 5 can be activated periodically for each measurement and in low power mode the rest of the time by being supplied by at least one auxiliary energy source 4 after energy extraction and accumulation of charges on an accumulator 27, or a small battery. The different measurements made by the sensors 5 are stored digitally in the volatile memory or the non-volatile memory of the memory unit 21 with indication of the time of the measurement by being clocked by the low frequency oscillator of the microcontroller 22. It can also be It is possible that the microcontroller 22 performs a preprocessing of the measurements before recording them in the memory unit.

As soon as the transponder module 2 carried by the mobile object approaches a defined short distance for detecting a reading device, the reading device transmits an interrogation and / or synchronization signal, which is received by the first antenna 12 ′ of the receiver 25 of the transponder circuit 20 of the transponder module 2. From this moment, synchronization of the transponder circuit 21 can be carried out and complete activation of the receiver and the transmitter is carried out. The stored measurement data are preferably completely transmitted at very high speed, for example greater than 10 Mbits / s and preferably of the order of 26 Mbits / s by the second antenna 12 of the activated UHF transmitter 23. However, the first antenna and the second antenna may also constitute only a single dual-band antenna. Once all the measurement data have been transmitted with indication of the time periods of each measurement, taking account for example of the synchronization of the transponder circuit 20, at least the transmitter 24, or even part of the receiver 25 are deactivated. The transmitter 24 and the receiver 25 remain in an idle mode until a new interrogation of a reading device is made when the transponder module 2 again approaches a reading device.

It should be noted that all of the measurement data transmitted by the transponder module 2 can be used in a treatment station for medical monitoring (biorhythm) or mobility habits of the person or animal carrying the module. with transponder 2.

From the description which has just been made, several alternative embodiments of the transponder module and of the communication system comprising it can be designed by those skilled in the art without departing from the scope of the invention defined by the claims.

Claims (19)

claims 1. Transponder module (2) intended to be placed on a mobile object (10) and arranged to transmit information near a reading device (3, 3 '), on the basis of an interrogation signal transmitted by the reading device (3, 3 ') and received by the transponder module (2), the transponder module comprising: - at least one energy source (4) for supplying energy for the power supply of the transponder module (2), - at least one sensor (5) to carry out one or more measurements of at least one physical parameter, - a microcontroller (22) connected to the measurement sensor (5) to receive the measurement (s) from the sensor (5), CH 714 449 A2 a memory unit (21) for storing in at least one memory the measurement data of the measurement or measurements carried out by the sensor (5) and processed in the microcontroller (22) for their storage, - a receiver arranged to receive at least one interrogation signal from a reading device (3, 3 '), when the transponder module (2) is located near a reading device (3, 3') , and - a transmitter (23) arranged to transmit measurement data stored on the basis of the interrogation of a reading device, characterized in that the transmitter (23) once activated is arranged to transmit measurement data signals memorized at ultra high frequency and very high speed following the reception of an interrogation signal from a nearby reading device. 2. transponder module (2) according to claim 1, characterized in that the transmitter (23) is able to transmit all the measurement data stored in the memory unit (21) once the receiver has received the signal interrogation of a reading device (3, 3 '). 3. transponder module (2) according to one of claims 1 and 2, characterized in that the UHF transmitter (23) is arranged to transmit measurement data signals at a carrier frequency greater than 2 GHz and preferably of around 5.8 GHz. 4. transponder module (2) according to one of claims 1 and 2, characterized and in that the UHF transmitter (23) is arranged to transmit measurement data signals at a rate greater than 10 Mbits / s and of preferably around 26 Mbits / s. 5. Transponder module (2) according to claim 1, characterized in that the transmitter (23) is able to transmit the stored measurement data modulated in phase of the OQPSK type. 6. transponder module (2) according to claim 1, characterized in that the energy source (4) is a backup energy source (4), which is a solar cell or a thermoelectric generator (TEG) or a magnetic induction circuit or a piezoelectric element. 7. transponder module (2) according to claim 1, characterized in that it comprises several auxiliary energy sources (4) connected to an extractor (26) of energy from the transponder module (2) to accumulate charges in an accumulator (27) or in a super-capacity element for electrically and continuously supplying the transponder module (2). 8. transponder module (2) according to claim 1, characterized in that the microcontroller (22) is clocked by an internal low frequency oscillator, which is an RC or ring type oscillator, and in that the microcontroller ( 22) is connected to the memory unit (21), which comprises at least one volatile memory, and to the receiver (25) and to the transmitter (23) to form a transponder circuit (20). 9. transponder module (2) according to claim 1, characterized in that it comprises several measurement sensors (5) each arranged to carry out one or more measurements of a respective physical parameter, and connected to the microcontroller (22) for storing the measurement data in the memory unit (21). 10. transponder module (2) according to claim 9, characterized in that the sensors (5) are arranged to carry out measurements of biorhythms of a person or an animal, which constitute the mobile object (10). 11. Transponder module (2) according to claim 9, characterized in that the microcontroller (22) is clocked by an internal low frequency oscillator, which is an RC or ring type oscillator, and in that the sensors ( 5) are arranged to each perform several measurements over time, all of the measurements being stored in the memory unit (21) in defined positions. 12. transponder module (2) according to claim 1, characterized in that the receiver (25) is arranged to receive one or more signals at a low frequency of the order of 125 kHz or at high frequency of the order of 13 MHz or more than 400 MHz and preferably of the order of 868 MHz. 13. transponder module (2) according to claim 12, characterized in that the receiver (25) is arranged to receive an interrogation and synchronization signal from a reading device (3, 3 ') near the transponder module (2). 14. transponder module (2) according to claim 13, characterized in that the transmitter (23) is arranged to be activated upon receipt of the interrogation and synchronization signal and by being clocked by a quartz oscillator of frequency around 26 MHz. 15. Transponder module (2) according to claim 1, characterized in that the memory unit (21) comprises a volatile memory and a non-volatile memory, and in that as a function of the level of the supply voltage, the microcontroller (22) is able to store the measurement data of one or more sensors (5) in the non-volatile memory, if the supply voltage level is above a defined threshold, and in the volatile memory, if the supply voltage level is below the defined threshold. 16. Information communication system (1) which comprises at least one transponder module (2) according to one of the preceding claims and at least one reading device (3,3 '), characterized in that the module with transponder (2) is able to communicate measurement data stored in a memory unit (21) of the module CH 714 449 A2 with ultra high frequency and very high speed transponder (2) following the reception of an interrogation signal from a nearby reading device. 17. Method for activating a transponder module (2) according to one of claims 1 to 15, in a system (1) for information communication, the method comprising the steps of: - carry out several measurements over time by one or more sensors (5) being controlled by a microcontroller (22) of the transponder module (2), which is continuously supplied by an energy source (4), - memorize all the measurement data processed by the microcontroller (22) in a memory unit (21), - receive an interrogation signal from a reading device (3, 3 ') by the receiver (25) of the transponder module (2), when it is near the reading device (3, 3'), - upon receipt of the interrogation signal, fully activate the ultra high frequency transmitter (23) for the transmission of measurement data stored at very high speed to the reading device (3, 3 ') in communication. 18. A method of actuating a transponder module (2) according to claim 17, characterized in that the receiver (25) of the transponder module (2) receives an interrogation and synchronization signal from the reading device. (3, 3 ') nearby to synchronize the microcontroller (22) and the stored measurement data. 19. Method for activating a transponder module (2) according to claim 17, characterized in that once the transmitter (23) has transmitted all the measurement data at very high speed within a period of time less than 1 second to the reading device in communication, it is deactivated and goes into a rest mode until the next interrogation of a reading device (3, 3 ').