WO2018130308A1

WO2018130308A1 - Rf-radiated activatable device

Info

Publication number: WO2018130308A1
Application number: PCT/EP2017/050743
Authority: WO
Inventors: Markus Warken
Original assignee: Nokia Solutions and Networks Oy
Current assignee: Nokia Solutions and Networks Oy
Priority date: 2017-01-16
Filing date: 2017-01-16
Publication date: 2018-07-19
Anticipated expiration: 2019-07-16

Abstract

It is provided an apparatus, comprising a first power source adapted to provide electrical power; a logical unit adapted to consume the electrical power provided by the first power source if the logical unit operates; a switch unit adapted to inhibit the consuming of the electrical power by the logical unit if the switch unit is switched off and to allow the consuming of the electrical power by the logical unit if the switch unit is switched on; an activator adapted to switch on the switch unit if the activator receives a predetermined first electromagnetic field.

Description

Title

RF-RADIATED ACTIVATABLE DEVICE

Field of the invention

The present invention relates to an apparatus and a method related to activatable devices. More particularly, the present invention relates to an apparatus and a method related to activatable loT devices.

Abbreviations

3GPP Third Generation Partnership Project

5G 5th Generation

CDMA Code Division Multiple Access

EDGE Enhanced Datarate for GSM Evolution

loT Internet of Things

LAN Local Area Network

LED Light Emitting Diode

LTE Long Term Evolution

LTE-A LTE-Advanced

LTE-M LTE Machine-to-Machine

MEMS Microelectromechanical systems

NB loT Narrowband loT

RFID Radio Frequency Identification

UMTS Universal Mobile Telecommunications System

UTRAN UMTS Terrestrial Radio Access Network

WLAN Wireless LAN Background of the invention

Many "things" in the Internet of Things, i.e. devices that are able to communicate with other devices, face issues with power supply. The requirement of low maintenance, in particular long battery life times, conflicts with communication requirements, for instance listening to some data channel to form ad hoc networks or similar. A typical example are fire detectors not only issuing an alarm in case of fire but capable to communicate to other fire detectors or a fire department. Another application are active labels on containers that have no power consumption at all while the container ship is at sea but get activated when the ship enters the harbour.

Conventionally known are autonomous loT devices that have their own power supply (battery) and have means to communicate with other devices. In the above example of a system of fire detectors, a key requirement of such a system of active fire detectors is to setup and maintain connections. This costs energy and even the most energy efficient implementation of several available implementations of "sleep modes" requires at least the ability to always receive signals, i.e. uses continuously power. A generalization of this concept for other applications is obvious.

With the basic principles of RFID systems it is possible, in principle, to build autonomously operating communication means for devices without the need of a power supply. In principle, in such devices, the electromagnetic field generates a current in an antenna which is rectified (e.g. by a diode). The resulting DC current may be accumulated in a capacity in order to increase the collected energy. For details, refer to conversion of electromagnetic radiation into electrical current [1 ].

[1 ] Negar Sani et al, All-printed diode operating at 1 .6 GHz,

http://www.pnas.Org/content/1 1 1 /33/1 1943.full

Summary of the invention

It is an object of the present invention to improve the prior art.

According to a first aspect of the invention, there is provided an apparatus, comprising a first power source adapted to provide electrical power; a logical unit adapted to consume the electrical power provided by the first power source if the logical unit operates; a switch unit adapted to inhibit the consuming of the electrical power by the logical unit if the switch unit is switched off and to allow the consuming of the electrical power by the logical unit if the switch unit is switched on; an activator adapted to switch on the switch unit if the activator receives a predetermined first electromagnetic field.

The activator may be electrically separated from the first power source such that the activator does not consume the electrical power from the first power source. The logical unit may operate if the switch unit is switched on.

The first power source may be at least one of a battery, a secondary battery, a fuel cell, and a solar panel. The apparatus may further comprise a monitoring unit adapted to monitor if a

predetermined first switch-off signal is received; a first switch-off unit adapted to switch off the switch unit if the predetermined first switch-off signal is received.

The logical unit may comprise a trigger unit adapted to provide a trigger at a time when the logical unit operates; and the apparatus may further comprise a timer unit adapted to determine when a predetermined time has elapsed after the trigger was provided; a signal provider adapted to provide a predetermined second switch-off signal if the predetermined time has elapsed; a second switch-off unit adapted to switch off the switch unit if the predetermined second switch-off signal is received.

The logical unit may be adapted to issue an activation signal when the logical unit operates; and the apparatus may further comprise a transmitting unit adapted to transmit a predetermined second electromagnetic field if the activation signal is received; and a second power source; wherein the transmitting unit may be adapted to consume an electrical power from the second power source when the transmitting unit transmits the second electromagnetic field.

The predetermined second electromagnetic field may have a second frequency characteristic corresponding to a first frequency characteristic of the predetermined first electromagnetic field. According to a second aspect of the invention, there is provided a method, comprising switching on a switch unit if a predetermined first electrical field is received, wherein the switch unit is adapted to inhibit a logical unit to consume electrical power provided by a first power source if the switch unit is switched off and to allow the logical unit to consume the electrical power if the switch unit is switched on; and the logical unit is adapted to consume the electrical power provided by the first power source if the logical unit operates.

The switching on of the switch unit may not consume the electrical power from the first power source.

The logical unit may operate if the switch unit is switched on.

The first power source may be at least one of a battery, a secondary battery, a fuel cell, and a solar panel.

The method may further comprise monitoring if a predetermined first switch-off signal is received; switching off the switch unit if the predetermined first switch-off signal is received.

The method may further comprise providing a trigger at a time when the logical unit operates;

determining when a predetermined time has elapsed after the trigger was provided;

providing a predetermined second switch-off signal if the predetermined time has elapsed; switching off the switch unit if the predetermined second switch-off signal is received.

The method may further comprise issuing an activation signal by the logical unit when the logical unit operates; transmitting a predetermined second electromagnetic field if the activation signal is received, wherein an electrical power from a second power source may be consumed when the transmitting unit transmits the second electromagnetic field.

The predetermined second electromagnetic field may have a second frequency characteristic corresponding to a first frequency characteristic of the predetermined first electromagnetic field. The method of the second aspect may be a method of device activation.

According to a third aspect of the invention, there is provided a computer program product comprising a set of instructions which, when executed on an apparatus, is configured to cause the apparatus to carry out the method according to the second aspect. The computer program product may be embodied as a computer readable medium or directly loadable into a computer.

According to some embodiments of the invention, at least one of the following advantages may be achieved:

Battery lifetime may be extended;

Power consumption may be reduced;

Maintenance efforts may be reduced.

It is to be understood that any of the above modifications can be applied singly or in combination to the respective aspects to which they refer, unless they are explicitly stated as excluding alternatives.

Brief description of the drawings

Further details, features, objects, and advantages are apparent from the following detailed description of the preferred embodiments of the present invention which is to be taken in conjunction with the appended drawings, wherein:

Fig. 1 shows an apparatus according to some embodiments of the invention;

Fig. 2 shows a method according to some embodiments of the invention; and

Figs. 3 to 7 show message sequence charts according to some embodiments of the invention.

Detailed description of certain embodiments Herein below, certain embodiments of the present invention are described in detail with reference to the accompanying drawings, wherein the features of the embodiments can be freely combined with each other unless otherwise described. However, it is to be expressly understood that the description of certain embodiments is given by way of example only, and that it is by no way intended to be understood as limiting the invention to the disclosed details.

Moreover, it is to be understood that the apparatus is configured to perform the corresponding method, although in some cases only the apparatus or only the method described.

With the basic principles of RFID systems it is possible, in principle, to build autonomously operating communication means for devices without the need of a power supply.

However, since only little energy can be collected from the radiation field, such communication system has strong limitations.

However, the energy that can be obtained directly from the radiation field in suitable time is large enough to trigger a power-up of a ready device that has a power supply. Hence, according to some embodiments of this invention, there are provided autonomous loT devices that reduce their power consumption to zero if not activated and can be activated by radiation. In the activated state (i.e., if the loT device operates), the loT device may consume power from a power source.

Fig. 1 shows an apparatus 1 according to some embodiments of the invention. The apparatus 1 comprises an energy source 10 such as a battery and a logical unit 30. In order to operate, the logical unit 30 requires power from the energy source 10. The energy source 10 is connected to the logical unit 30 via a switch unit 20. If the switch unit 20 is closed, the energy source 10 is electrically connected to the logical unit such that the logical unit 30 may consume power from the energy source 10 in order to operate. If the switch unit 20 is open, the energy source 10 is not electrically connected to the logical unit 30. Hence, the logical unit 30 cannot operate.

The switch unit 20 is operated by an activator 40 such as an activation transponder. The activator 40 collects (harvests) energy out of an external electromagnetic field. For example, the activator 40 may be a RFID transponder which collects energy out of an electromagnetic field of a specific frequency range. In some embodiments, the switch unit 20 may be normally off. However, if the activator 40 collects sufficient energy from the electromagnetic field, the activator 40 may switch on the switch unit 20. If the activator 40 does not collect sufficient energy any more, the switch unit 20 is switched off again. For example, the switch unit may be a normally-off transistor such as a FET, where the activator 40 controls the gate voltage, and the energy source 10 and the logical unit 30 are connected to source and drain of the transistor, respectively. In some embodiments, the switch unit may be a relay, e.g. based on MEMS technology. In some embodiments of the invention, the switch unit 20 may switch off with some delay after activator 40 does not have sufficient energy to switch on the switch unit 20. This delay may be realized by an electrical buffer unit such as a capacity.

In some embodiments, the switch unit 20 may be bi-stable. If the switch unit 20 is off and the activator 40 has collected sufficient energy, the activator 40 switches on the switch unit 20. The switch unit 20 remains on until a switch-off signal is given to switch off the switch unit 20. For example, a switch-off signal may be generated by a timer after a certain event happened in the logical unit 30 (e.g. the last activity in the logical unit 30), and/or it may be received from an external device.

In some embodiments, the logical unit 30 may be configured to run specific SW conducting or enabling communication with another device. A SW timer may be used to terminate this state of communication readiness. On expiration of said timer the device may switch off switch unit 20, thus saving energy.

In some embodiments, the switch unit 20 remains switched on for a predetermined time after it was switched on. In some embodiments, the logical unit 30 may comprise some logic to switch off the switch unit 20 dependent on certain parameters or status.

In some embodiments of the invention, if the switch unit 20 is switched on and the power source 10 is electrically connected to the logical unit 30, the logical unit 30 starts operating. In some embodiments of the invention, the logical unit may start operating only if a further condition is fulfilled. For example, in the case of a fire detector, a bimetal switch may be additionally included in the connection between the power source 10 and the logical unit 30 such that the electrical connection between the power source 10 and the logical unit 30 is only established if there is a certain minimum temperature. If the temperature is lower than the minimum temperature, absence of fire may be assumed such that the fire detector does not issue an alarm.

In some embodiments of the invention, the apparatus 1 may additionally comprise a transmitting unit 50 (optional, as indicated by dashed lines) connected to the logical unit 30. For example, the transmitting unit 50 may be used to activate one or more further apparatuses similar to the apparatus 1 . For this purpose, the transmitting unit 50 may transmit an electromagnetic field suitable to activate the activators of one or more other similar apparatuses in the surroundings. That is, the electromagnetic field transmitted by the transmitting unit 50 is such that the activator of a similar apparatus in the surroundings can collect sufficient energy from the electromagnetic field in order to switch on the switch unit in the similar apparatus.

For example, the electromagnetic field transmitted by the transmitting unit 50 may be modulated such that it transfers a signal generated by the logical unit 30. Thus, the apparatus may communicate with other apparatuses by wireless means, e.g. according to WLAN, LTE including the emerging LTE-M and NB loT standards, or other, even vendor proprietary communication systems.

The transmitting unit 50 may obtain the necessary energy from the energy source 10 or from a separate energy source. The logical unit 30 may activate the transmitting unit 50 to transmit the electromagnetic field according to the logic implemented in the logical unit 30.

In some embodiments, the apparatus 1 may communicate with other apparatuses e.g. via a glass fiber or via an electric wire. The electric wire may also be used as a power supply if it is connected to some power source such as a power grid.

Fig. 2 shows a method according to some embodiments of the invention. The apparatus 1 according to Fig. 1 may perform the method of Fig. 2 but is not limited to this method. The method of Fig. 2 may be performed by the apparatus 1 of Fig. 1 but is not limited to being performed by this apparatus.

The method comprises switching on a switch unit (such as switch unit 20 of Fig. 1 ) if a predetermined first electrical field is received (S10). The switch unit is adapted to inhibit a logical unit (such as logical unit 30 of Fig. 1 ) to consume electrical power provided by a power source (such as power source 10 of Fig. 1 ) if the switch unit is switched off and to allow the logical unit to consume the electrical power if the switch unit is switched on. If the logical unit operates, the logical unit consumes the electrical power provided by the power source.

Figs. 3 to 7 show message sequence charts according to some embodiments of the invention. In Figs. 3 to 7, the same reference signs as in Fig. 1 are used for corresponding unit, i.e. apparatus 1 comprising power source 10, switch unit 20, logical unit 30, activator 40, and optionally transmitting unit 50. Bold dashed lines indicate that the logical unit 30 consumes power from the power source 10 unless the bold dashed line is crossed out by "X". In this case, the switch unit 20 is switched off such that the logical unit 30 does not consume power from the power source 10.

Fig. 3 shows a message sequence wherein the apparatus 1 reduces its power consumption to zero based on inactivity for a certain time. Inactivity is a specific example of a timer that may be used to switch off the switching unit 10 of Fig. 1 . Another example may be switching off after a certain activity has been performed.

As shown in Fig. 3, the power source 10 is electrically connected to the logical unit 30 via the switch unit 20 which is switched on. The logical unit 30 comprises an inactivity timer 33 which is started after every operation. If the inactivity timer detects that an operation has not been performed it triggers the activator 40 to switch off the switch unit 20 (S31 ). Based on the trigger from the inactivity timer, the activator 40 switches off the switch unit 20 (S32). Thus, the logical unit 30 does not receive power from the power supply 10 anymore, stops operation, and reduces its power consumption to zero.

In the embodiment shown in Fig. 3, switching off is performed by the activator 40 but in some embodiments, the switch unit 20 may be switched off by a deactivator different from the activator 40, based on the trigger signal from a timer such as the inactivity timer.

Fig. 4 shows a message sequence, wherein the apparatus 1 reduces its power consumption to zero based on a trigger received from external. E.g. the trigger may be received from another similar apparatus, more particularly, from a transmitting unit 54 of the other apparatus.

If the logical unit 30, powered by the power source 10 (switch unit 20 is switched on), receives an external trigger to switch off (S41 ), it instructs the activator 40 (or a separate deactivator) to switch off the switch unit 20 (S42). The activator 40 (or the separate deactivator) switches off the switch unit 20 (S43). Thus, the logical unit 30 does not receive power from the power supply 10 anymore, stops operation, and reduces its power consumption to zero.

According to some embodiments of the invention, the apparatus 1 may comprise both a timer such as the inactivity timer 33 and a reception unit to receive an external trigger signal. In these apparatuses, the switching unit 20 may be switched off whenever one of the timer expires and the external trigger is received. In some embodiments, the switching unit 20 may be switched off only if both the timer expires and the external trigger is received.

Fig. 5 shows a message sequence to activate the apparatus 1 . Namely, while the switching unit 20 is switched off such that the logical unit 30 cannot consume power from the power source 10, the activator 40 receives an electromagnetic field which allows the activator to collect (harvest) sufficient energy to switch on the switching unit 20 (S51 ). The electromagnetic field may be provided e.g. from a transmitting unit 55 of another similar apparatus or from some other external entity.

If the activator 40 collects sufficient energy, the activator 40 switches on the switching unit 20 (S52). Thus, the power source 10 is electrically connected to the logical unit 30 such that the same may operate. In some embodiments, the logical unit 30 starts to operate as soon as the switching unit 20 is switched on such that the power source 10 is electrically connected to the logical unit 30.

An example of a real use case of such embodiments are intelligent "labels" for containers, that can be activated when a container ship enters the harbour and informs about recipient, status of goods within the container, addressee, etc. In this case, the electromagnetic field may be generated from an external RFID reader, and the activator 40 may be substantially a RFID tag (transponder) which switches on the switching unit 20 if sufficient energy is received from the electromagnetic field

According to one implementation example, on activation the unit (intelligent label) attached to a container performs checks on the content of the container like measuring temperature, humidity, consistency of gas or liquid mix allowing to conclude on the state of content, in one example the ripeness of fruit. This information may then be transmitted to a logical device in the harbor infrastructure, in one example operated by the harbor operators, in another by the recipient of the goods, in a third by the transport operator. This information may be used to decide on priority of further transportation or corrective action to save goods from spoiling.

Fig. 6 shows another message sequence to activate the apparatus 1 . Namely, while the switching unit 20 is switched off such that the logical unit 30 cannot consume power from the power source 10, the activator 40 receives an electromagnetic field which allows the activator to collect (harvest) sufficient energy to switch on the switching unit 20 (S61 ). The electromagnetic field may be provided e.g. from a transmitting unit 56 of another similar apparatus or from some other external entity. If the activator 40 collects sufficient energy, the activator 40 informs the external entity (e.g. transmitting unit 56) that it is ready (S62). Then, the external entity (e.g. transmitting unit 56) instructs the activator 40 to switch on the switching unit 20 (S63). Such instruction may be transmitted e.g. by a modulation of the electromagnetic field from which the activator 40 collected sufficient energy (i.e., the electromagnetic field carries a signal), or it may be transmitted in a signal transmitted on a different frequency band.

Based on this instructions, the activator 40 switches on the switching unit 20 (S64). Thus, the power source 10 is electrically connected to the logical unit 30 such that the same may operate.

Fig. 7 shows a message sequence which starts when the logical device 30 is operating, i.e. if the switch unit 20 is switched on. For example, the message sequence may follow after one of the message sequences of Figs. 5 and 6.

If the logical unit 30 operates it may issue an activation signal to the transmitting unit 50 to transmit an electromagnetic field in order to activate one or more activatable devices similar to apparatus 1 (an example of an activatable device such as loT activatable device) (S71 ). In response to the activation signal, the transmitting unit 50 transmits an electromagnetic field to the outside (S72).

If the electromagnetic field is received by an activatable device such as device 17 shown in Fig. 7, device 17 may start to operate. For example, device 17 may have a similar structure as apparatus 1 comprising an energy source, a switch unit, a logical unit, an activator, and optionally a transmitting unit. Thus, if the electromagnetic field transmitted by the transmitting unit 50 of apparatus 1 is received by the activator of device 17, the latter may switch on the switching unit of the device 17 such that the logical unit of the device 17 may operate.

If the device 17 has a transmitting unit, too, its logical unit may then activate the transmitting unit such that another electromagnetic field is transmitted. This

electromagnetic field may activate further activatable devices within reach of the device 17 (but outside reach of apparatus 1 ). Thus, the activation may be cascaded over plural activatable devices.

The electromagnetic field transmitted by the transmitting unit 50 should be such that it can activate the activatable device 17. For example, if the device 17 and the apparatus 1 are of the same type, the electromagnetic field transmitted by the transmitting unit 50 may have a same frequency characteristic as the electromagnetic field from which the activator 40 may collect sufficient energy to switch on the switching unit 20. However, the frequency characteristics need not be exactly the same. For example, the transmitted

electromagnetic field may have a broader frequency band than the frequency band from which the activator 40 collects energy, or it may comprise only a subrange of this frequency band. Thus, in the above example, the transmitted electromagnetic field should have a frequency characteristic corresponding to that of the electromagnetic field harvested by the activator 40.

The field strength of the transmitted electromagnetic field may be adapted to the distance to the next activatable device (such as device 17) and the sensitivity of the same. Thus, unnecessary energy consumption by the transmitting unit 50 may be avoided.

An example of an application of such an apparatus is a system of fire detectors which have very low power consumption. Each of the fire detectors has a fire detection part and a communication part. The fire detection part runs permanently on battery. E.g. the fire detection part may detect smoke due to scattering of light.

On the other hand, the communication part is normally fully switched off (power consumption = 0). The communication part corresponds to an apparatus 1 including the transmitting unit 50. If the fire detection part of a first one of the fire detectors detects a fire, it switches on the switch unit 20. That is, the switching unit may be switched on not only by the activator 40 but also by the fire detection part. Then, the logical unit 30 of the communication part can operate, powered by the power source 10. As a part of the logic implemented in the logical unit 30, the logical unit 30 activates the transmitting unit 50 to transmit an electromagnetic field (see Fig. 7). Thus, the communication parts of other fire detectors (which may have a similar setup as the apparatus 1 ) are activated although their respective fire detection parts might not have detected the fire yet. That is, the fire detectors set up an ad-hoc network.

In some embodiments, the transmitting unit 50 may be switched off by the logical unit 30 after a predetermined time (supposed to be sufficient to activate neighbored fire detectors) in order to save energy.

For example, each of the fire detectors may issue an acoustic alarm if activated. Thus, not only persons in the direct neighborhood of the first fire detector are warned. Furthermore, the fire detectors may communicate the location of the first fire detector which has detected the fire. Thus, an operation center may be informed of the location of the fire by an arbitrary fire detector although the first fire detector may not be in reach of the operation center.

If there are plural zones in an area, the fire detectors of each zone may operate on the same (or corresponding) frequency band of the electromagnetic field, but the fire detectors of different zones may operate on different frequency bands. Thus, a fire alarm may be issued only by the fire detectors of one zone but not by those of other zones.

A power source may be e.g. a battery, a secondary battery, a fuel cell, a solar panel, or a connection to a power grid. Even in the latter case, embodiments of the invention help to save energy.

A logical unit is not particularly restricted. It may be any circuit. For example, the logical circuit may transmit information on the device (such as a serial number) stored in a memory. It may transmit information on a property of the device (such as a maximum or minimum temperature in the past, if the device comprises a sensor which detects (and potentially stores) this information). It may transmit information on the environment of the device such as the occurrence of a fire. It may transmit a combination of such information. It may also activate a device such as a LED connected to the logical unit. It may also activate a transmitting unit to transmit an electromagnetic wave. The electromagnetic wave may or may not comprise a signal. The devices connected to the logical unit may use the power supply of the logical unit or a separate power supply.

According to some embodiments of the invention, the communication between activated activatable devices (such as apparatus 1 ) may be performed according to a wireless standard such as 3GPP (e.g. LTE, LTE-A, LTE-M, or 5G). Other communication standards such as CDMA, EDGE, UTRAN, WLAN etc. including wireline standards and also proprietary communication protocols may be employed.

One piece of information may be transmitted in one or plural messages from one entity to another entity. Each of these messages may comprise further (different) pieces of information.

Names of network elements, protocols, and methods are based on current standards. In other versions or other technologies, the names of these network elements and/or protocols and/or methods may be different, as long as they provide a corresponding functionality. If not otherwise stated or otherwise made clear from the context, the statement that two entities are different means that they perform different functions. It does not necessarily mean that they are based on different hardware. That is, each of the entities described in the present description may be based on a different hardware, or some or all of the entities may be based on the same hardware. It does not necessarily mean that they are based on different software. That is, each of the entities described in the present description may be based on different software, or some or all of the entities may be based on the same software. According to the above description, it should thus be apparent that example embodiments of the present invention provide, for example an loT device, or a component thereof, an apparatus embodying the same, a method for controlling and/or operating the same.

It is to be understood that what is described above is what is presently considered the preferred embodiments of the present invention. However, it should be noted that the description of the preferred embodiments is given by way of example only and that various modifications may be made without departing from the scope of the invention as defined by the appended claims.

Claims

Claims:

1 . Apparatus, comprising

a first power source adapted to provide electrical power;

a logical unit adapted to consume the electrical power provided by the first power source if the logical unit operates;

a switch unit adapted to inhibit the consuming of the electrical power by the logical unit if the switch unit is switched off and to allow the consuming of the electrical power by the logical unit if the switch unit is switched on;

an activator adapted to switch on the switch unit if the activator receives a predetermined first electromagnetic field.

2. The apparatus according to claim 1 , wherein

the activator is electrically separated from the first power source such that the activator does not consume the electrical power from the first power source.

3. The apparatus according to any of claims 1 and 2, wherein

the logical unit operates if the switch unit is switched on.

4. The apparatus according to any of claims 1 to 3, wherein

the first power source is at least one of a battery, a secondary battery, a fuel cell, and a solar panel.

5. The apparatus according to any of claims 1 to 4, further comprising

a monitoring unit adapted to monitor if a predetermined first switch-off signal is received;

a first switch-off unit adapted to switch off the switch unit if the predetermined first switch-off signal is received.

6. The apparatus according to any of claims 1 to 5, wherein

the logical unit comprises a trigger unit adapted to provide a trigger at a time when the logical unit operates; and the apparatus further comprises

a timer unit adapted to determine when a predetermined time has elapsed after the trigger was provided;

a signal provider adapted to provide a predetermined second switch-off signal if the predetermined time has elapsed;

a second switch-off unit adapted to switch off the switch unit if the predetermined second switch-off signal is received.

7. The apparatus according to any of claims 1 to 6, wherein

the logical unit is adapted to issue an activation signal when the logical unit operates; and the apparatus further comprises

a transmitting unit adapted to transmit a predetermined second electromagnetic field if the activation signal is received; and

a second power source; wherein

the transmitting unit is adapted to consume an electrical power from the second power source when the transmitting unit transmits the second electromagnetic field.

8. The apparatus according to claim 7, wherein

the predetermined second electromagnetic field has a second frequency characteristic corresponding to a first frequency characteristic of the predetermined first electromagnetic field.

9. Method, comprising

switching on a switch unit if a predetermined first electrical field is received, wherein

the switch unit is adapted to inhibit a logical unit to consume electrical power provided by a first power source if the switch unit is switched off and to allow the logical unit to consume the electrical power if the switch unit is switched on; and

the logical unit is adapted to consume the electrical power provided by the first power source if the logical unit operates.

10. The method according to claim 9, wherein

the switching on of the switch unit does not consume the electrical power from the first power source.

1 1 . The method according to any of claims 9 and 10, wherein

the logical unit operates if the switch unit is switched on.

12. The method according to any of claims 9 to 1 1 , wherein

13. The method according to any of claims 9 to 12, further comprising

monitoring if a predetermined first switch-off signal is received;

switching off the switch unit if the predetermined first switch-off signal is received.

14. The method according to any of claims 9 to 13, further comprising

providing a trigger at a time when the logical unit operates;

determining when a predetermined time has elapsed after the trigger was provided; providing a predetermined second switch-off signal if the predetermined time has elapsed;

switching off the switch unit if the predetermined second switch-off signal is received.

15. The method according to any of claims 9 to 14, further comprising

issuing an activation signal by the logical unit when the logical unit operates;

transmitting a predetermined second electromagnetic field if the activation signal is received, wherein

an electrical power from a second power source is consumed when the transmitting unit transmits the second electromagnetic field.

16. The method according to claim 15, wherein

17. A computer program product comprising a set of instructions which, when executed on an apparatus, is configured to cause the apparatus to carry out the method according to any of claims 9 to 16.

18. The computer program product according to claim 17, embodied as a computer readable medium or directly loadable into a computer.