HK40010013B - Rfid transponder-based module for communicating information to a reading device - Google Patents

Description

RFID transponder-based module for transmitting information to a reading device

Technical Field

The invention relates to an RFID transponder based module for transmitting information to a reading device, which module may be passive or semi-passive.

The invention also relates to a system for communicating information with an RFID transponder based module.

The invention also relates to a method of enabling an RFID transponder based module to transmit information to a reading device.

Background

For transmitting information, RFID communication between the transponder and the reader, in particular via a Near Field Connection (NFC) or a bluetooth connection, is generally used. The transponder, which may be passive, is first awakened by the reader interrogation signal and a rectifier in the transponder makes it possible to tap the supply voltage for operating the transponder from the received signal. Generally, upon waking up, the transponder may transmit, for example, a constant information item, which is the identification code of the transponder or of the product or object on which the transponder is placed. The transponder therefore transmits this constant information item at the request of the RFID reader in communication.

In conventional RFID transponders, the transmission of data or constant information items is effected at an average bit rate of the order of several hundred kilobits/second. This requires a considerable data transmission time and thus a relatively large consumption. This in principle does not allow to allow sufficient power supply using only energy tapped off from an external auxiliary source connected to the transponder circuit until all data are transmitted, thus constituting a drawback.

In the case of connection via bluetooth, synchronization with the reader is first performed. Furthermore, a complex and difficult-to-operate communication protocol that consumes a large amount of current is used. Therefore, it is not conceivable to use such a communication via bluetooth for a passive or semi-passive transponder powered by extracting energy from external energy, thus constituting a drawback.

The transponder or portable RFID device may be placed on an object or person or animal in motion. The transponder may comprise sensors for performing measurements of various physical parameters of the object or the person or animal. These measurements may be transmitted to a reader or base station for remote processing or use of the measurements. However, the transponder or portable RFID device must be powered by a sufficient energy source to be able to transmit the measurement values of the performed measurements without excessive consumption, which is difficult to perform with prior art transponders or portable devices.

Patent application WO 2012/125425A1 may be cited, which describes a portable device in the form of a patch with various sensors. The portable device may be placed on a person to determine various physiological parameters (biorhythms) of the person by means of several sensors. The measured values of the performed measurements may be stored and transmitted to a processing station which manages the measurements performed on the person, for example by the portable device, for medical examinations. The portable device includes a battery to provide the necessary power to obtain various measurements via the sensor. However, such portable devices cannot operate without a power supply battery and they cannot periodically make measurements and quickly transmit the stored information to the processing station with reduced energy consumption, thus constituting a drawback.

Disclosure of Invention

It is therefore an object of the present invention to provide an RFID transponder based module for transmitting information to a reading device which alleviates the above-mentioned disadvantages of the prior art and operates at low supply voltages in order to be able to periodically perform measurements by means of at least one sensor and to be able to quickly transmit said measurements when the reading device passes by.

To this end, the invention relates to an RFID transponder-based module for transmitting information, comprising the features mentioned in independent claim 1.

Particular forms of module based on RFID transponders are defined in the dependent claims 2 to 15.

An advantage of the transponder-based module according to the invention is that it can be powered by drawing energy from an auxiliary energy source, allowing it to operate partially, in order to perform measurements by means of at least one sensor and preferably by means of a certain number of sensors. Thus, the transponder-based module can remain continuously powered and perform measurements by the sensor in order to store the measurement results in a memory unit with at least one volatile memory. The sensor is connected to a microcontroller which can be regulated by an oscillator with low power consumption, such as an RC or ring oscillator.

Once communication can be established with a nearby reader, all measurement data can be transmitted at a very high bit rate by a transmitter which is activated at least from this moment in a very short time span. Upon receiving an interrogation and/or synchronization signal from the RFID reading device, the oscillator of the transmitter may be woken up in order to adjust or time the measurement data transmission operation. Once all stored measurement data has been transmitted, the transmitter may again be in idle mode.

To this end, the invention also relates to an information transfer system comprising the features mentioned in the independent claim 16.

To this end, the invention also relates to a method of using a transponder-based module in an information transfer system, which method comprises the features mentioned in independent claim 17.

Specific steps of the method are defined in the dependent claims 18 and 19.

Drawings

The objects, advantages and features of an RFID transponder based information communication module, a communication system including the same, and a method of using an RFID transponder based module will become more apparent in the following description, which is based on at least one non-limiting embodiment shown in the accompanying drawings, in which:

FIG. 1 is a simplified view of an information communication system having at least one transponder-based module and one or more reading devices for high bit rate communication of information from the transponder-based module to nearby reading devices, according to the present invention, and

fig. 2 shows a simplified block diagram of the electronic components of an RFID transponder-based module according to the present invention, which has one or more measurement sensors and one or more energy supply sources for powering the RFID transponder-based module.

Detailed Description

In the following description, the RFID transponder based module for transmitting information to at least one reading device in the vicinity and the electronic components of a data communication system comprising the module, which are known to a person skilled in the art, are described only in a simplified manner.

Fig. 1 shows a system for transmitting data or commands 1. The system 1 essentially comprises at least one transponder-based module 2, which at least one transponder-based module 2 can be placed on a moving object 10, such as a human or animal, or any type of vehicle, and one or more reading devices 3,3' arranged at different locations in a defined area. The location of the reading device 3,3' may be in a public place, a house, a shop, a natural path, a city area or in a different other location.

The transponder-based module 2, for example placed on a human or animal 10, may be of a passive or semi-passive type. According to the embodiment shown in fig. 1, which comprises a transponder circuit 20, at least one power supply 4 and at least one measuring sensor 5 of the transponder circuit 20, the transponder circuit 20 can be personalized for the carrier of the transponder-based module 2.

The power supply 4 is preferably an auxiliary energy source, which may be a solar cell, a thermoelectric generator (TEG), also known as Seebeck generator, a magnetic induction circuit, a piezoelectric element or optionally a small battery. Energy extraction from the backup or auxiliary energy source may be operated by the transponder circuit 20 to charge a charging battery so that voltage may be supplied to the transponder circuit 20. A combination of several auxiliary energy sources 4 may be used to power the transponder circuit.

Preferably, the transponder-based module 2 may include a set of sensors 5 coupled to the transponder circuit 20. It is conceivable to use various sensors 5 for measuring physiological parameters (biorhythms) of the human or animal 10, at least for a determined period of time. Depending on the application, the set of sensors 5 may comprise temperature sensors, pressure sensors, pulse meters, magnetic sensors, accelerometers, gyroscopes, optical sensors or other types of sensors. The measurements performed by the sensors may be at least temporarily stored in the at least one memory after sampling or analog-to-digital conversion, as explained below with reference to fig. 2.

With one or more auxiliary energy sources 4, the transponder circuit 20 and a major part of the electronic components of the sensor 5 can be operated continuously, since their energy consumption is considerably reduced. On the other hand, when the transponder-based module 2 is close to the reader device 3, for example less than 50cm away therefrom, the reader device 3 transmits an interrogation and/or synchronization signal via at least one antenna 11 to the transponder-based module 2 at a carrier frequency of, for example, 868 MHz. This has the effect of fully activating all electronic components of the transponder-based module 2. In this fully activated state, the transponder-based module 2 can transmit, via the antenna 12, most of the measurement data stored via the UHF transmitter assigned to the reader device 3 in the interrogation state, which reader device 3 receives these measurement data via the antenna 11. Preferably, all measurements performed by the sensor 5 associated with the transponder circuit 20 are transmitted at a very high bit rate, for example at a bit rate of about 26Mbits/s and at an ultra high frequency of about 5.8 GHz.

It should be noted that in case of transmission at very high bit rates and ultra high transmission frequencies, all stored measurements originating from the sensor 5 can be transmitted very quickly in a very short time of less than 1s and without requiring high electrical consumption of the transponder based module 2. Once all measurement data has been transmitted, the transmitter of the transponder circuit 20 can enter an idle mode before a new interrogation of the reading device 3, 3'.

Such a transponder-based module 2 can be used for monitoring the biorhythm of a human or animal 10 (moving object) in which the measurements performed by the sensor vary continuously. The reading device 3 can be arranged, for example, in a part of a house or garden or, if the animal is a cat, in a cat hole to obtain all the stored measurements of the sensor in operation. Since the sensor measurements can be made at low voltages and low consumption, the transponder-based module 2 remains continuously activated for this part of the transponder circuit 20. When a human or animal (e.g. a cat in a cat hole) passes, the transmitter of the module remains idle until interrogated by the reading device 3. Each reading device 3,3' can still be coupled to a central unit, for example a computer, by cable or wirelessly, for managing all the measurement data.

Fig. 2 shows the electronic components of the RFID transponder based module 2 in more detail in order to better understand the way it operates.

The transponder-based 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 may be auxiliary energy sources 4 from which energy may be extracted to power the transponder circuit 20 and other parts of the transponder-based module 2.

One sensor or n sensors, sensor 1 to sensor n, are coupled to the microcontroller 22, the microcontroller 22 preferably being regulated by a low frequency clock originating from a low consumption oscillator, for example an RC-type oscillator or a ring oscillator. The measurements performed by the sensors are digitally converted in the microcontroller to be stored at defined locations in the memory unit 21. The converted measurement data are in principle stored in volatile memories of the SRAM type, because of the low consumption required for storage in this type of memory. However, if the magnitude of the supply voltage is sufficient, it is also conceivable to store these measurement data in a non-volatile memory, such as a flash memory, which requires more information storage consumption. Under these conditions, the magnitude of the supply voltage can be detected in the microcontroller in order to know the type of memory in which the measurement data can be stored. Below a defined voltage threshold, measurement data may be stored in volatile memory, whereas above this voltage threshold, measurement data may be stored in non-volatile memory NVM (non-volatile memory).

As mentioned above, several auxiliary energy sources 4 may be provided, or indeed one small battery may also be provided. Energy is extracted from these energy sources by a well-known extractor 26, which well-known extractor 26 is shown as a diode in the transponder circuit 20. The accumulator (capacitor) 27 at the output of the extractor is charged so as to be able to supply the transponder circuit 20 with a supply voltage. However, instead of a battery, an ultracapacitor element may also be required if an auxiliary energy source is permanently present, such as vibration of a motor or a permanent operating reservoir.

The transponder-based module 2 further comprises a receiver 25, which receiver 25 may be a HF high-frequency signal receiver 25, in order to receive a high-frequency signal SR from the reading device 3 in the interrogation state via the first antenna 12'. A conventional rectifier (not shown) in the HF-signal receiver 25 can be envisaged for rectifying the acquired signal and also for energizing the power supply of the transponder-based module 2. The high frequency signal may be a signal having a carrier frequency greater than 400MHz, for example a frequency of 434MHz, 868MHz or 916MHz, preferably 868 MHz. The HF receiver 25 may be partially idle or some of the receiving parts may be permanently activated before the signal transition. These enabling parts of the receiver consume only very little current as long as no conversion of the received signal is performed.

The transponder-based module 2 further comprises a transmitter 23 for transmitting, when activated, an ultra-high frequency signal ST via the second antenna 12. This transmitter 23 is regulated by its own quartz oscillator 24, which may have an oscillation frequency of, for example, about 26 MHz. Once the interrogation signal is received by the receiver 25, the oscillator 24 of the transmitter 23 and a conventional frequency synthesizer may be coordinated to perform a conversion of the signal acquired by the first antenna 12'.

It should also be noted that for the wake-up and reception of signals by the transponder-based module 2, the receiver 25 is able to acquire low-frequency signals of about 125kHz or high-frequency signals of about 13MHz (NFC) or more than 400MHz, for example 868 MHz. The conversion of the signal is performed based on an RC oscillator of the microcontroller 22. Under these conditions, the receiver may remain permanently activated.

It is also conceivable that the wake-up of the transponder-based module 2 is performed by any other means, for example by receiving light, infrared, ultrasonic or other signals.

Once the transponder-based module 2 carried by the moving object has approached a short distance from the reading device, for example only for NFC near field communication, the reading device sends an interrogation and/or synchronization signal to the transponder-based module 2, which interrogation and/or synchronization signal is detected nearby by the transponder-based module 2. From this moment on, the transponder-based module 2 can use its oscillator 24 to fully activate the receiver 25 and the transmitter 23, allowing it to transmit the data signal S at an ultra-high frequency _T Transmitting data signals S, e.g. at carrier frequencies higher than 2GHz, preferably about 5.8GHz _T . Once the transmitter is started, all the measurement data stored in the memory unit 21 and conditioned by the RC oscillator of the microcontroller 22 are transmitted, the transmitter being able to transmit data at low power due to the proximity of the reading device. The measurement data may be phase modulated (OQPSK) and transmitted at a very high bit rate, for example at a bit rate of about 26 Mbits/s.

Since each transponder-based module comprises an identification code, for example personalized for the person or animal carrying the module, it is possible to allow querying several transponder-based modules in the vicinity of one and the same reading device. There is no risk of collision of the measurement data transmitted by each activated transmitter in the vicinity of one and the same reading device.

The supply voltage for operating the transponder based module 2 may be less than 3v, for example about 0.6v, preferably drawn from the at least one auxiliary energy source 4. Once communication with the reading device has been performed, the energy of the signal acquired in reception can be obtained by means of a rectifier, so as to also supply power to the transponder-based module 2.

According to the method of enabling the RFID transponder based module 2 to transmit information to a reading device, it is provided that several measurements over time are performed via one or more sensors 5 according to the command of the microcontroller 22 of the transponder based module 2. At least the microcontroller 22 and the sensor 5 can be activated periodically at each measurement and in a low power mode for the remaining time, by being powered by at least one auxiliary energy source 4 or by a small battery after energy extraction and charge accumulation on the accumulator 27. The various measurements performed by the sensor 5 are digitally stored in a volatile or non-volatile memory of the storage unit 21 and have an indication of the time of the measurement, which is regulated by a low frequency oscillator of the microcontroller 22. The microcontroller 22 may also perform a pre-processing of the measurements before recording them in the memory unit.

As soon as the transponder-based module 2 carried by the moving object approaches a short detection distance defined from the reading device, the reading device transmits an interrogation and/or synchronization signal, which is acquired by the first antenna 12' of the receiver 25 of the transponder circuit 20 of the transponder-based module 2. From this point on, synchronization of the transponder circuit 20 may be performed and full activation of the receiver and transmitter may be performed. The stored measurement data are preferably transmitted completely by the second antenna 12 of the activated UHF transmitter 23 at a very high bit rate, for example a bit rate of more than 10Mbits/s, and preferably about 26 Mbits/s. However, the first antenna and the second antenna may constitute only a single dual-band antenna. Once all measurement data has been transmitted, e.g. by synchronization of the transponder circuit 20, and indicating the time period of each measurement, at least a part of the transmitter 24 or indeed of the receiver 25 is deactivated. The transmitter 24 and the receiver 25 remain in idle mode until the moment when the reading device re-interrogates when the transponder-based module 2 is again close to the reading device.

It should be noted that all measurement data transmitted by the transponder-based module 2 can be used in the processing station for medical examinations (biorhythms) or for tracking the movement habits of the person or animal carrying the transponder-based module 2.

Based on the description just given, a person skilled in the art can design several variant embodiments of the transponder-based module and of the communication system comprising it without departing from the scope of the invention as defined by the claims.

Claims (19)

1. A transponder-based module (2) for placement on a moving object (10) and designed to transmit information in the vicinity of a reading device (3,3 ') based on an interrogation signal transmitted by the reading device (3,3') and received by the transponder-based module (2), the transponder-based module comprising:

at least one energy source (4) for supplying energy to the power supply of the transponder-based module (2),

at least one sensor (5) for performing one or more measurements of at least one physical parameter,

a microcontroller (22) coupled to the sensor (5) for receiving a measurement or measurements of the sensor (5),

a storage unit (21) for storing measurement data of one or more measurements in at least one memory, the one or more measurements being performed by the sensor (5) and processed in a microcontroller (22) for storage of the measurement data,

-a receiver (25) designed to receive at least one interrogation signal from a reading device (3,3 ') when a transponder-based module (2) is located in the vicinity of the reading device (3,3'), and

a transmitter (23) which is designed to transmit the stored measurement data upon interrogation by the reading device,

characterized in that said microcontroller (22) is regulated by a low-frequency internal oscillator, which is an RC or ring oscillator, in order to regulate, over time, the measurements performed by the sensor (5), which are stored in a storage unit (21) and have an indication of the time of each measurement in the low-power mode, and

wherein the transmitter (23), which is activated as soon as the receiver (25) of a nearby reading device receives the interrogation signal, is designed to transmit the stored signal of the measurement data at an ultra-high frequency and a very high bit rate, wherein the transmitter (23) is designed to transmit the signal of the measurement data at a bit rate of more than 10Mbits/s,

wherein the storage unit (21) comprises a volatile memory and a non-volatile memory, and wherein, depending on the magnitude of the supply voltage, the microcontroller (22) is capable of storing measurement data of one or more sensors (5) in the non-volatile memory if the magnitude of the supply voltage is greater than a defined threshold value, and storing measurement data of one or more sensors (5) in the volatile memory if the magnitude of the supply voltage is less than a defined threshold value.

2. Transponder-based module (2) according to claim 1, characterized in that the transmitter (23) is designed to signal measurement data at a bit rate of about 26 Mbits/s.

3. Transponder-based module (2) according to claim 1, characterized in that the transmitter (23) is able to transmit all measurement data stored in the memory unit (21) as soon as the receiver receives an interrogation signal from the reading device (3,3').

4. Transponder-based module (2) according to claim 1, characterized in that the transmitter (23) is designed to transmit signals of measurement data at a carrier frequency greater than 2 GHz.

5. Transponder-based module (2) according to claim 4, characterized in that the transmitter (23) is designed to transmit a signal of measurement data at a carrier frequency of about 5.8 GHz.

6. Transponder-based module (2) according to claim 1, characterized in that the transmitter (23) is able to transmit stored measurement data of an OQPSK type phase modulation.

7. Transponder-based module (2) according to claim 1, characterized in that the energy source (4) is an auxiliary energy source (4), the auxiliary energy source (4) being a solar cell or a thermoelectric generator (TEG) or a magnetic induction circuit or a piezoelectric element.

8. Transponder-based module (2) according to claim 1, characterized in that it comprises a plurality of auxiliary energy sources (4) coupled to the energy extractor (26) of the transponder-based module (2) in order to accumulate electric charges in the accumulator (27) or supercapacitor element, so as to continuously supply power to the transponder-based module (2).

9. Transponder-based module (2) according to claim 1, characterized in that the microcontroller (22) is coupled to a storage unit (21) comprising at least one volatile memory and to a receiver (25) and a transmitter (23) to form a transponder circuit (20).

10. Transponder-based module (2) according to claim 1, characterized in that it comprises a plurality of sensors (5), each designed to perform one or more measurements of a respective physical parameter, and each coupled to a microcontroller (22) for storing measurement data in a memory unit (21).

11. Transponder-based module (2) according to claim 10, characterized in that the sensor (5) is designed to perform measurements on the biorhythms of humans or animals constituting the moving object (10).

12. Transponder-based module (2) according to claim 10, characterized in that a plurality of sensors (5) are designed to each perform a plurality of measurements over time, all measurements being stored in defined positions in a memory unit (21).

13. Transponder-based module (2) according to claim 1, characterized in that the receiver (25) is designed to receive one or more signals of low frequency of about 125kHz, about 13MHz, greater than 400 MHz.

14. Transponder-based module (2) according to claim 13, characterized in that the receiver (25) is designed to receive interrogation and synchronization signals originating from a reading device (3,3') in the vicinity of the transponder-based module (2).

15. Transponder-based module (2) according to claim 14, characterized in that the transmitter (23) is designed to be activated immediately after receiving the interrogation and synchronization signals and to be conditioned by a quartz oscillator with a frequency of about 26 MHz.

16. A system (1) for information communication, comprising at least one transponder-based module (2) according to claim 1 and at least one reading device (3,3'), characterized in that the transponder-based module (2) is capable of transmitting measurement data stored in a memory unit (21) of the transponder-based module (2) at ultra-high frequencies and very high bit rates after receiving an interrogation signal from a nearby reading device.

17. A method of using a transponder-based module (2) according to claim 1 in a system (1) for information communication, the method comprising the steps of:

-performing a plurality of measurements over time by means of one or more sensors (5) controlled by a microcontroller (22) of the transponder-based module (2), the transponder-based module (2) being continuously powered by the energy source (4),

-storing all measurement data processed by the microcontroller (22) in a memory unit (21) and indicating the time of each measurement in the low power mode,

-receiving an interrogation signal from a reading device (3,3 ') via a receiver (25) of a transponder based module (2) when the receiver (25) of the transponder based module (2) is located in the vicinity of the reading device (3,3'),

-upon reception of the interrogation signal, fully activating the transmitter (23) at the ultra high frequency immediately for transmitting the stored measurement data to the reading device (3,3') in communication at a very high bit rate.

18. Method according to claim 17, characterized in that the receiver (25) of the transponder-based module (2) receives interrogation and synchronization signals from a nearby reading device (3,3') in order to synchronize the microcontroller (22) with the stored measurement data.

19. Method according to claim 17, characterized in that once the transmitter (23) has transmitted all measurement data to the reading device at a very high bit rate in a time interval of less than 1 second in the communication, said transmitter (23) is deactivated and enters idle mode until the next interrogation of the reading device (3,3').