WO2008132269A1

WO2008132269A1 - Short range communication

Info

Publication number: WO2008132269A1
Application number: PCT/FI2007/050233
Authority: WO
Inventors: Ville V. Ranki; Iiro Jantunen; Kimmo Kalliola; Jani Ollikainen
Original assignee: Nokia Corporation
Priority date: 2007-04-26
Filing date: 2007-04-26
Publication date: 2008-11-06

Abstract

Disclosed is a device (202), including a communication unit configured to operate on a communication frequency, wherein the communication unit includes a tunable element (205), which tunable element has an initial frequency band, which prevents a signal on the communication frequency from traversing the communication unit, and is configured to tune away from the initial frequency band responsive to being in proximity of a transmitter (201 ) of a predefined type, such that a signal on the communication frequency is allowed to traverse the communication unit. Also disclosed are related other devices, methods and systems.

Description

SHORT RANGE COMMUNICATION

FIELD OF THE INVENTION

The present invention generally relates to the field of communications and particularly, but not exclusively, to proximity detection and/or allowing communication only at short range.

BACKGROUND OF THE INVENTION

Conventionally, wireless communication systems have been designed such that the communication range is maximized. There are, however, use cases where it is desired that the communication takes place at very short range only.

In many cases where it is desired that only short range communication is enabled, so called near field communication is used. The term near field communication covers various short-range techniques and technologies which enable wireless communication between devices when they are touched together or brought close together. The term near field communication covers, among other things, various contactless close-to-touch connectivity technologies which involve electromagnetic and/or electrostatic coupling. The term covers the RFID (Radio Frequency IDentification) technology as well as the specific NFC (Near Field Communication) technology specified by following standardization bodies: NFC Forum, International Organization for Standards (ISO) and ECMA International. Despite the fact that the acronym NFC has a particular meaning specified by the NFC Forum, in the following description the acronym NFC is used in the place of near field communication in its broadest sense. The operating distance achieved by different near field communication techniques is typically from around O cm to around few tens of centimeters.

Even with near field communication, there are certain sensitive application areas, e.g. transfer of classified or otherwise sensitive information, where one may desire to further limit the "normal" communication range so that only devices very close to each other may communicate. One example of such use case is electrical payment/ticketing where payment information can be read from a payment card or the like over a radio interface. It is desirable that the payment information can be read only when the payment card is placed very close to a reader device so that the owner of the payment card can control the use of the payment card. That is, reading the payment information from further away, possibly without the owner of the payment card even noticing such event, should not be allowed.

Another example case is the use of UHF RFID (Radio Frequency Identification at Ultra High Frequency) tags as it may be desirable that the tags cannot be read over a long distance due to privacy reasons or simply to make sure that the correct tag is read when there are tags many around.

In order to be able to allow communication only between devices very close to each other a mechanism to detect proximity of another device is needed. One way to achieve this is to require physical connection before communication is allowed. This, however requires physical connectors on both of the devices and positioning the devices so that the connectors are physically touching each other. This may be difficult to achieve and may thus lead to inconvenient user experience. Another way is to monitor transmission power as transmission power attenuates over distance and thereby is at its maximum when the devices are very close to each other. This is not a reliable method though, as the original transmission power may be easily increased whereby a transmitter further away may appear to be close by.

SUMMARY

Now an alternative mechanism to allow communication only at short range is provided.

According to a first aspect of the invention there is provided a device, comprising: a communication unit configured to operate on a communication frequency, wherein the communication unit comprises a tunable element, which tunable element has an initial frequency band, which prevents a signal on the communication frequency from traversing the communication unit, and is configured to tune away from the initial frequency band responsive to being in proximity of a transmitter of a predefined type, such that a signal on the communication frequency is allowed to traverse the communication unit.

According to a second aspect of the invention there is provided a method, comprising: maintaining in a tunable element residing in a communication unit an initial frequency band, which prevents a signal on a communication frequency from traversing the communication unit, and responsive to being in proximity of a transmitter of a predefined type, tuning the tunable element away from the initial frequency band such that a signal on the communication frequency is allowed to traverse the communication unit.

According to a third aspect of the invention there is provided a communication module, wherein. the communication module is configured to operate on a communication frequency, and wherein the communication module comprises a tunable element, which tunable element has an initial frequency band, which prevents a signal on the communication frequency from traversing the communication module, and is configured to tune away from the initial frequency band responsive to being in proximity of a transmitter of a predefined type, such that a signal on the communication frequency is allowed to traverse the communication module.

The communication module may be comprised of one or more chips or chipsets.

According to a fourth aspect of the invention there is provided a device, comprising: means for communicating configured to operate on a communication frequency, and means for tuning configured to initially tune the means for communicating to an initial frequency band, which prevents a signal on the communication frequency from traversing the means for communicating, and responsive to being in proximity of a transmitter of a predefined type, to tune the means for communicating away from the initial frequency band such that a signal on the communication frequency is allowed to traverse the means for communicating.

A device or communication module relating to the first four aspects may further comprise a secure module configured to be accessed through the communication unit.

According to an embodiment of the invention the device may be for example an RFID tag or a device capable of emulating an RFID tag.

In an embodiment of the invention the transmitter of the predefined type comprises a piece of material configured to cause said tuning of the tuning element. The piece of material may be dielectric material or conductive material, for example. In another embodiment of the invention the transmitter the predefined type comprises an antenna configured to cause said tuning of the tuning element.

The tunable element may be configured to be automatically tuned responsive to being in proximity of the transmitter of a predefined type.

The communication unit or the communication module of various embodiments of the invention may be a near field communication unit.

In an embodiment of the invention a device relating of one of the first four aspects of the invention further comprises an element, which is configured to be waken up responsive to the tuning of the tunable element. The element that is waken up may be a secure module or a separate communication element. Also more than one element may be waken up.

According to a fifth aspect of the invention there is provided a device, comprising: a communication unit configured to operate on a communication frequency, a processing unit configured to co-operate with the communication unit to communicate with an external device, and an arrangement configured to tune a tunable element of the external device responsive to being in proximity of the external device so as to allow communication between the second device and the external device.

The arrangement in the device of the fifth aspect may be a specifically designed antenna or it may be comprised of a piece of predefined material. The predefined material may be dielectric material or conductive material, for example. Additionally, the arrangement may be such that it automatically tunes the tunable element of the external device.

The device of the fifth aspect may be for example a reader device configured to read an external secure module or smart card.

According to a sixth aspect of the invention there is provided a system comprising a first device and a second device, wherein the first device comprises a communication unit configured to operate on a communication frequency, the communication unit comprising a tunable element, which tunable element has an initial frequency band, which prevents a signal on the communication frequency from traversing the communication unit, and wherein the second device comprises a communication unit configured to operate on the communication frequency, a processing unit configured to co-operate with the communication unit to communicate with the first device, and an arrangement configured to tune the tunable element of the first device responsive to being in proximity of the first device so as to allow a signal on the communication frequency to traverse the communication unit of the first device.

The first device may be for example a device of one of the first four aspects of the invention and the second device may be for example a device of the fifth aspect of the invention. In various embodiments of various aspects of the invention the frequency band of the tunable element may be tuned into the communication frequency or away from the communication frequency responsive to being in proximity of the transmitter of a predefined type.

The tunable element may be for example one of the following: a band pass filter, a band reject filter, and an antenna. In practise an antenna may be configured to provide the functionality of a band pass filter or a band reject filter.

Various embodiments of the present invention have been illustrated only with reference to certain aspects of the invention. It should be appreciated that corresponding embodiments may apply to other aspects as well.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described, by way of example only, with reference to the accompanying drawings, in which:

Fig. 1 shows a flow diagram of a method according to an embodiment of the invention;

Fig. 2A shows a block diagram illustrating logical components of a system according to an embodiment of the invention; Fig. 2B shows a block diagram illustrating logical components of a system according to another embodiment of the invention; Fig. 3 shows a block diagram of a device suited for operating according to various embodiments of the invention, and Fig. 4 shows a block diagram of a reader device according to an embodiment of the invention.

DETAILED DESCRIPTION

In the following description, like numbers denote like elements. A principle of some embodiments of the invention is to use a tunable element that does not allow communication in its initial setting. Configuration of the tunable element is such that proximity of a transmitter of a predefined type automatically tunes the tunable element so as to allow communication. Then if the transmitter is no longer close by, the tunable element returns to its initial setting. In this way communication is allowed only at short range.

In an embodiment of the invention reading of a secure module or a smartcard, such as an RFID tag or payment card, may be prevented in the initial setting, whereas proximity of a transmitter of a predefined type may allow accessing the secure module. Some other embodiments of the invention may be applied in other scenarios, such as communication of other types of sensitive data.

Figure 1 shows a flow diagram of a method according to an embodiment of the invention. The procedure is started and in phase 102 an initial frequency band is maintained in a tunable element of a communication unit. The communication unit operates on an operating frequency and may be coupled to a secure module, which may be accessed through the communication unit. The initial frequency band is such that signals on the communication frequency are prevented from traversing the communication unit. That is, the tunable element does not pass through signals on the communication frequency and the communication (and reading the secure module) is disabled.

Then if proximity of a transmitter is detected in phase 103, the frequency band of the tunable element is tuned in phase 104 so as to allow signals on the communication frequency to traverse the communication unit. That is, after tuning the tunable element does pass through signals on the communication frequency and the communication (and reading the secure module) is enabled. Depending on the tunable element, it may be tuned into the communication frequency (e.g. if the tunable element operates as a band pass filter) or away from the communication frequency (e.g. if the tunable element operates as a band reject filter). If proximity of a transmitter is not detected in phase 103, the procedure resumes to phase 102.

Likewise, when proximity of a transmitter is not detected anymore, the tunable element is tuned back to the initial frequency band, whereby the communication is again disabled. In this way for example reading the secure module such as an RFID tag or a payment card may be enabled only when the reading device is in proximity of the device hosting the secure module.

It must be noted that phases 103 and 104 may be automatic in the sense that proximity of a transmitter may automatically cause the desired tuning of the tunable element. This may be achieved with certain physical arrangements, which are further discussed below.

In an embodiment of the invention the tuning of the tunable element is based on the fact that antenna tuning may change in proximity of another antenna. In other words, insertion loss of a system at certain frequency may change when transmitting and receiving antennas are brought close to each other. By tuning the antennas so that this throughput is maximized when the antennas are next to each other, and minimized when they are far away from each other, one may gain additional attenuation at longer distances. This phenomenon may be employed to make a system that only works at short distances. For example loop antennas may be used for obtaining this phenomenon.

Figure 2A shows a block diagram illustrating logical components of a system according to an embodiment of the invention. The system comprises a transmitter 201 and a receiver 202. The transmitter may be a reader device and the receiver may be a device hosting a secure module that is to be read. Alternatively the transmitter and the receiver may be Bluetooth devices communicating with each other.

The transmitter side 201 comprises a transmitting device 203 and an antenna 204, which may operate e.g. on a 900 MHz frequency band according to one embodiment of the invention. The receiver side 202 comprises an antenna 206, a tunable band pass filter 207, and a band pass filter 208. The band pass filter according to one embodiment of the invention operates on a 900 MHz frequency band (i.e. passes through signals on the 900 MHz band), which is the desired communication frequency according to one embodiment of the invention.

The frequency band of the tunable band pass filter 207 is tuned responsive to distance between the receiver 202 and the transmitter 201. The tunable band pass filter is tuned to 900 MHz frequency band when located in proximity of the transmitter 201. When the receiver 202 is further away from the transmitter 201 , the frequency band of the band pass filter 207 is further away from the desired 900 MHz communication frequency, thereby rejecting signals on the 900 MHz band. As a result the receiver 202 only detects a clear signal when both band pass filters 207 and 208 are at the same frequency (which happens when the receiver and transmitter are close to each other) and thus communication is only possible at short distances.

In an embodiment of the invention the functionality of the band pass filter 207 is provided by the antenna 206, that is, the band pass filter 207 is not a physically separate component but instead a logical component illustrating functionality provided by the antenna 206. The antenna 206 and the band pass filter 207 as logical components form a tunable element 205. Alternatively it is possible that there is an antenna and a separate, tunable filter.

It is clear that the system of Figure 2A usually comprises other components, too, but for the sake of clarity they are not shown.

Figure 2B shows a block diagram illustrating logical components of a system according to another embodiment of the invention. This embodiment is otherwise similar to the one shown in Figure 2A, but now the band pass filter 207 is replaced by a band reject filter 217, which is tuned away from the communication frequency for allowing communication. In this case the receiver 212 only detects a clear signal when the band reject filter 217 and the band pass filter 208 are not at the same frequency. Also in this case the functionality of the band reject filter 217 may be provided by the antenna 216, that is, the band reject filter 217 does not need to be a physically separate component. Instead it may be a logical component illustrating functionality provided by the antenna 216. The antenna 216 and the band pass filter 217 as logical components form a tunable element 215. Alternatively it is possible that there is an antenna and a separate, tunable filter.

An advantage that may be achieved with a band reject filter arrangement is that such system is not sensitive to the exact amount of filter off-tuning. Instead it suffices that the off-tuning of the tunable filter/antenna is large enough.

It must be noted that the frequencies presented in connection with Figures 2A and 2B are only examples and that various other frequency bands may be equally applied according to various embodiments of the present invention.

Like mentioned above, the frequency of a loop antenna may be configured to tune responsive to the distance to another loop antenna. Thereby a loop antenna may be configured to provide the functionality of the band pass or band reject filters 207 and 217. In addition to radiating antennas also some other distance-sensitive tunable elements may be used in embodiments of the invention.

For example a microstrip antenna may be used to provide the functionality of the band pass filter 207 of Figure 2A or the band reject filter 217 of Figure 2B. Tuning of a microstrip antenna may be caused for example by bringing dielectric material into the electric field of the microstrip antenna.

The wavelength at a specific frequency is shorter in dielectric material than in vacuum. Therefore resonance frequency of a microstrip antenna becomes lower when dielectric material is brought into its electric field.

Resonance frequency f_ro of a half wavelength antenna can be defined

Where:

Ero is permittivity between the strip and ground level, and

/ is length of the wire.

If material with ε > 1 is placed on top of the strip (into the electric field of the microstrip antenna) the resonance frequency f_r is decreased even more.

Resonance frequency f_r obtained when dielectric material is brought into the electric field of the microstrip antenna can be defined f f_r * ψ=,

Where: ε_r is permittivity of the dielectric material, which is brought into the electric field, and f_ro is the original resonance frequency without the dielectric material in the electric field.

In the exemplary system illustrated on Figures 2A and 2B, according to an embodiment of the invention a suitable piece of dielectric material may be arranged in the transmitter 201 , whereby tuning of a microstrip antenna in the receiver 201 is achieved when the transmitter 201 is in proximity of the receiver 202. Alternatively some other material causing the tuning of the antenna may be placed in the transmitter instead of the dielectric material. For example using suitable conducting material instead of the dielectric material may cause the desired effect.

Like mentioned above the solutions of various embodiments of the invention may be used in connection with reading secure modules, such as RFID tags or payment cards. Additionally or alternatively various embodiments of the invention may be used in other cases. Various embodiment of the invention may suit for cases concerning communication of sensitive data, for example. In an embodiment of the invention the tuning of a tunable element is used as a wake-up signal. In one scenario the tuning of a tunable element is used for triggering a Bluetooth connection between a transmitting and a receiving device. For example the devices may be paired over the short range communication and/or the information needed for establishing a Bluetooth connection (e.g. BD_ADDR, Bluetooth Device Address, and possibly also clock information) may be transferred over the short range communication. In this way the transmitting device may start paging the receiving device right away and, as the receiving device has been triggered to a page scan state as a result of the short range communication allowed through the tunable element, the Bluetooth connection may be established relatively quickly. Additionally one may achieve that initially the Bluetooth chip in the receiving device may be in power save mode and waken up only when necessary, whereby one may save power.

In another scenario the tuning of a tunable element is used for waking up a secure module, such as an RFID tag. Let's consider for example a tag, which has its own battery to be used for conducting more complicated tasks. By default such tag may be in sleep/power save mode and may be "waken up", if the tunable element is tuned so that communication is allowed. That is, if a transmitter signal reaches the secure module, it is waken up, and the transmitter signal is allowed to reach the secure module only if the transmitter and the secure module (or a device hosting the secure module) are close to each other.

A secure module or a smart card related to various embodiments of the invention may comprise a secure storage area. The secure storage area may be used for storing data in a tamperproof environment on the smartcard. Such data may comprise secure applications, private data, important receipts or the like. The secure module may be connected to a power source, which provides necessary power to the secure module for powering it up or shutting it down. The secure module may be further connected to a communication unit discussed above in connection with various embodiments of the invention for allowing communication between the secure module and external devices. Both reading and writing operations may be allowed to be conducted both to and from external tags/devices and also peer-to-peer type communication between two devices may be allowed.

In addition to the secure or sensitive data the secure module may comprise informational data such as user information, purpose of usage and validity information. As an example a digital ticket data transmitted by a ticket issuing entity represents the sensitive data and related informational data may be for example clear text information relating to the content description as written today on paper-form tickets.

User access to the secure storage area and data stored therein may be limited. As an example, a user may be allowed to read only the informational data relating to some sensitive data. Such a limitation of the read access may be obtained for example by at least partially coding and encrypting the sensitive data. Access to the secure storage area or specifically defined data fields in the secure storage area may be allowed for an authorized entity.

Figure 3 shows a block diagram of a device 300 suited for operating according to various embodiments of the invention. The device 300 may be for example a mobile communication device or some other device capable of hosting a secure module.

The device 300 comprises an antenna 301 for providing an air interface, a communication unit 302, and a secure module 306 accessible through the communication unit. The communication unit may comprise for example the receiver 202 of Figure 2A or the receiver 212 of Figure 2B or the like arrangement comprising a tunable element. Also the antenna 301 may be the tunable element of various embodiments of the invention.

Further the device comprises a memory 304 comprising operating instructions and software 305, and a processor 303 for executing the operating instructions and running the software and accordingly controlling other blocks of the device. The processor 303 is typically a central processing unit (CPU) or a master control unit MCU. Alternatively, the processor may be a microprocessor, a digital signal processor or an application specific integrated circuit, a field programmable gate array, a microcontroller or a combination of such elements. Additionally the device 300 may comprise a user interface (not shown) for providing output to a user and reading user input. The user interface typically comprises, for data output, a display and/or a speaker. For data input, the user interface typically comprises one or more of the following: dedicated buttons, soft keys, touch screen, roller, microphone, voice recognition circuitry, and pointing device.

The communication unit 302 is typically some near field communication unit. In addition to the near field communication unit the device 300 may further comprise another wireless communication unit for enabling longer range communication, for example according to GSM (Global System for Mobile communications), 3G (3^rd Generation Network) or WLAN (Wireless Local Area Network) technology.

As an alternative to the device shown in Figure 3 also less advanced devices may be suited for operating according to various embodiments of the invention. Such device may be an RFID tag, for example, and the blocks typically comprised in such devices are the antenna 301 , the communication unit 302, and the secure module 306 of Figure 3. A further variation of the device 300 is a device without the secure module 306. Such device may suit for implementing some embodiments of the invention.

Figure 4 shows a block diagram of a reader device 400 according to an embodiment of the invention. The reader device 400 may be for example an RFID reader or other near field communication reader. The reader device 400 may also be a mobile communication device operating as a NFC reader.

The reader device 400 comprises an antenna 401 for providing an air interface, a communication unit 403, a memory 404 comprising operating instructions and software 405, and a processor 403 for executing the operating instructions and running the software and accordingly controlling other blocks of the reader device. The processor 403 is typically a central processing unit (CPU) or a master control unit MCU. Alternatively, the processor may be a microprocessor, a digital signal processor or an application specific integrated circuit, a field programmable gate array, a microcontroller or a combination of such elements. The communication unit 402 in combination with the antenna 401 provides for example near field communication functionality. The near field communication functionality may be used for accessing external secure modules over air interface or just for providing near field communication between devices.

In an embodiment of the invention the antenna 401 is configured to cause the above discussed tuning effect, which allows reading a secure module residing for example in the device 300 of Figure 3, when the reader device 400 and the device 300 are close to each other.

In another embodiment of the invention the reader device comprises a block of dielectric material 406 (shown with dashed line) that will cause the above discussed tuning effect, which allows communication with the device 300 of Figure 3 for example, when the reader device 400 and the device 300 are close to each other. Alternatively the block 406 may be some other predefined type of material, such as conductive material, for example. The block 406 may be just an additional piece of material in the reader device or some components of the reader device may be arranged so as to form a combination providing equal functionality as a separate piece of additional material. The latter option provides the advantage that additional material does not need to be added to the reader device or that only small amount of material needs to be added.

It should be appreciated that in this document, words comprise, include and contain are each used as open-ended expressions with no intended exclusivity.

Particular implementations and embodiments of the invention have been described by way of non-limiting examples. It is clear to a person skilled in the art that the invention is not restricted to details of the embodiments presented above, but that it can be implemented in other embodiments using equivalent means without deviating from the characteristics of the invention. Furthermore, some of the features of the above-disclosed embodiments of this invention could be used without the corresponding use of other features. As such, the foregoing description should be considered as merely illustrative of the principles of the present invention, and not in limitation thereof. Hence, the scope of the invention is only restricted by the appended patent claims.

Claims

Claims:

1. A device, comprising: a communication unit configured to operate on a communication frequency, wherein the communication unit comprises a tunable element, which tunable element has an initial frequency band, which prevents a signal on the communication frequency from traversing the communication unit, and is configured to tune away from the initial frequency band responsive to being in proximity of a transmitter of a predefined type, such that a signal on the communication frequency is allowed to traverse the communication unit.

2. A device according to claim 1 , wherein the frequency band of the tunable element is configured to be tuned into the communication frequency or away from the communication frequency responsive to being in proximity of the transmitter of a predefined type.

3. A device according to claim 1 or 2, wherein the tunable element is one of the following: a band pass filter, a band reject filter, and an antenna.

4. A device according to any one of claims 1-3, wherein the device further comprises a secure module configured to be accessed through the communication unit.

5. A device according to claim 4, wherein the device is an RFID tag or a device capable of emulating an RFID tag.

6. A device according to any one of claims 1-5, wherein the transmitter of the predefined type comprises a piece of material configured to cause said tuning of the tuning element.

7. A device according to claim 6, wherein the piece of material is dielectric material or conductive material.

8. A device according to any one of claims 1-5, wherein the transmitter of the predefined type comprises an antenna configured to cause said tuning of the tuning element.

9. A device according to any one of claims 1-8, wherein the tunable element is configured to be automatically tuned responsive to being in proximity of the transmitter of a predefined type.

10. A device according to any one of claims 1-9, wherein the communication unit is a near field communication unit.

11. A device according to any one of claims 1-10, further comprising an element, which is configured to be waken up responsive to the tuning of the tunable element.

12. A device according to claim 11 , wherein said element is a secure module or a separate communication element.

13. A method, comprising: maintaining in a tunable element residing in a communication unit an initial frequency band, which prevents a signal on a communication frequency from traversing the communication unit, and responsive to being in proximity of a transmitter of a predefined type, tuning the tunable element away from the initial frequency band such that a signal on the communication frequency is allowed to traverse the communication unit.

14. A method according to claim 13, wherein the tuning comprises tuning the frequency band of the tunable element into the communication frequency or away from the communication frequency.

15. A method according to claim 13 or 14, wherein the tunable element is one of the following: a band pass filter, a band reject filter, and an antenna.

16. A method according to any one of claims 13-15, further comprising allowing a secure module to be accessed through the communication unit.

17. A method according to any one of claims 13-16, wherein the transmitter of the predefined type comprises a piece of material configured to cause said tuning of the tuning element.

18. A method according to claim 17, wherein the piece of material is dielectric material or conductive material.

19. A method according to any one of claims 13-16, wherein the transmitter of the predefined type comprises an antenna configured to cause said tuning of the tuning element.

20. A method according to any one of claims 13-19, further comprising automatically tuning the tunable element responsive to being in proximity of the transmitter of a predefined type.

21. A method according to any one of claims 13-20, further comprising waking up a predefined element responsive to the tuning of the tunable element.

22.A method according to claim 21 , wherein said predefined element is a secure module or a separate communication element.

23.A communication module, wherein. the communication module is configured to operate on a communication frequency, and wherein the communication module comprises a tunable element, which tunable element has an initial frequency band, which prevents a signal on the communication frequency from traversing the communication module, and is configured to tune away from the initial frequency band responsive to being in proximity of a transmitter of a predefined type, such that a signal on the communication frequency is allowed to traverse the communication module.

24.A communication module according claim 23, wherein the communication module is comprised of one or more chipsets.

25.A communication module according to any one of claims 23-24, wherein the communication module further comprises a secure module.

26.A communication module according to any one of claims 23-25, further comprising an element, which is configured to be waken up responsive to the tuning of the tunable element.

27.A communication module according to claim 26, wherein said element is a secure module or a separate communication element.

28.A device, comprising: means for communicating configured to operate on a communication frequency, and means for tuning configured to initially tune the means for communicating to an initial frequency band, which prevents a signal on the communication frequency from traversing the means for communicating, and responsive to being in proximity of a transmitter of a predefined type, to tune the means for communicating away from the initial frequency band such that a signal on the communication frequency is allowed to traverse the means for communicating.

29.A device according to claim 28, wherein the device further comprises a secure module configured to be accessed through the means for communicating.

30. A device according to any one of claims 28-29, further comprising means for waking up at least one predefined element responsive to the tuning of the tunable element.

31.A device according to claim 30, wherein said at least one predefined element is a secure module or a separate communication element.

32.A device, comprising: a communication unit configured to operate on a communication frequency, a processing unit configured to co-operate with the communication unit to communicate with an external device, and an arrangement configured to tune a tunable element of the external device responsive to being in proximity of the external device so as to allow communication between the second device and the external device.

33.A device according to claim 32, wherein said arrangement comprises a piece of predefined material.

34.A device according to claim 33, wherein the predefined material is dielectric material or conductive material.

35.A device according to claim 32, wherein said arrangement is an antenna.

36.A device according to any one of claims 32-35, wherein said arrangement is configured to tune the tunable element to the communication frequency or away from the communication frequency.

37.A device according to any one of claims 32-36, wherein said arrangement is configured to automatically tune the tunable element.

38.A system comprising a first device and a second device, wherein the first device comprises a communication unit configured to operate on a communication frequency, the communication unit comprising a tunable element, which tunable element has an initial frequency band, which prevents a signal on the communication frequency from traversing the communication unit, and wherein the second device comprises a communication unit configured to operate on the communication frequency, a processing unit configured to co- operate with the communication unit to communicate with the first device, and an arrangement configured to tune the tunable element of the first device responsive to being in proximity of the first device so as to allow a signal on the communication frequency to traverse the communication unit of the first device.