WO2021032740A1

WO2021032740A1 - Method for operating a mobile radio communication system

Info

Publication number: WO2021032740A1
Application number: PCT/EP2020/073100
Authority: WO
Inventors: Alaa Mourad; Alexander Krebs
Original assignee: Bayerische Motoren Werke Aktiengesellschaft
Priority date: 2019-08-20
Filing date: 2020-08-18
Publication date: 2021-02-25
Also published as: DE102019122391A1

Abstract

The invention relates to a method for operating a mobile radio communication system, wherein the method comprises: sending a first message (ADV_INF) from a first mobile radio communication device (Device 1) to a second mobile radio communication device (Device 2), sending a connection request (CONNECT_REQ) from the second mobile radio communication device (Device 2) to the first mobile radio communication device (Device 1), receiving an indication of a connection of the first mobile radio communication device (Device 1) to the second mobile radio communication device (Device 2), starting a first and a second timer (T1, T2) on the first and second mobile radio communication devices (Device 1, Device 2) on the basis of reception of the indication, sending information regarding an event (event) beginning at a second time (t2) from the first mobile radio communication device (Device 1) to the second mobile radio communication device (Device 2) at a first time (t1), processing the information by means of the second mobile radio communication device (Device 2) such that the second mobile radio communication device (Device 2) determines its own event time (eventT) at which the event (event) is expected by the second mobile radio communication device (Device 2), and activating the second mobile radio communication device (Device 2) at its own event time (eventT) such that the second mobile radio communication device (Device 2) then receives the event (event) from the first mobile radio communication device (Device 1).

Description

Method for operating a Mobilfunkko communication system

The present invention relates to a method for operating a cellular radio communication system.

Bluetooth and the protocols based on it are used, among other things, for Internet of Things (IOT) applications. Such IOT applications are now widespread in motor vehicles. Energy consumption and time synchronization play important roles here, which often conflict with one another.

The accuracy or reliability of such time synchronizations are often not particularly high in Bluetooth-based IOT applications, not least due to back transmissions and connection-based events. As a result, the use and the possibility of time synchronization are tightly limited.

It would therefore be desirable to provide a possibility which can make it possible to enable improved time synchronization, while at the same time the energy consumption of the relevant mobile radio communication systems is low.

It is the aim of the invention to propose a possibility that at least part of the prior art the known art avoids or at least reduced disadvantages.

The object is achieved according to the invention by means of a method according to the main claim, as well as by means of secondary method and device claims.

The subject matter of the main claim relates to a method for operating a

Mobile radio communication system, the method comprising: sending a first message from a first mobile radio communication device to a second mobile radio communication device. Sending a connection request from the second mobile radio communication device to the first mobile radio communication device. Receiving an indication or a confirmation of a connection between the first mobile radio communication device and the second mobile radio communication device by the first mobile radio communication device and by the second mobile radio communication device. Starting a first timer on the first mobile radio communication device based on the receipt of the notification or the confirmation of the connection of the first

Cellular communication device with the second cellular communication device. Starting a second timer on the second mobile radio communication device based on the receipt of the information or the confirmation of the connection of the first mobile radio communication device to the second Cellular communication device. Sending activation information from the first mobile radio communication device to the second mobile radio communication device at a first point in time, the activation information item having information relating to an event starting at a second point in time. Processing of the received activation information by the second mobile radio communication device in such a way that the second mobile radio communication device determines its own event time at which the event is expected by the second mobile radio communication device. And activate the second mobile radio communication device at its own event time, such that the second

Mobile radio communication device is set up at its own event time to receive the event from the first mobile radio communication device.

The process steps can be carried out automatically.

A mobile radio communication device within the meaning of the invention means a device for mobile data communication, preferably also for mobile voice communication. They are there

Mobile radio communication devices set up to communicate with one another in a Bluetooth mobile radio network.

One of the two mobile radio communication devices is preferably a personal mobile radio communication device of a motor vehicle user, while the second mobile radio communication device is preferably that of the motor vehicle of the motor vehicle user. A connection request within the meaning of the invention means making contact between one of the two mobile radio communication devices and the other mobile radio communication device for the purpose of establishing a mobile communication link between the two mobile radio communication devices.

A note within the meaning of the invention means information that provides information that the two mobile radio communication devices are connected to one another. The note thus indicates a confirmation of a

Connection of the first cellular communication device to the second cellular communication device. This information can be given by the first mobile radio communication device and by the second mobile radio communication device to the respective other mobile radio communication device. In a simple case, the information from a mobile radio communication device only contains information that it has received a data packet from the other mobile radio communication device. A timer within the meaning of the invention means a piece of time information which continuously indicates a period of time since the start of the timer. The timer can have a resolution and / or inaccuracy which is in the millisecond range, preferably in the microsecond range.

A resolution here means the smallest displayable unit of the timer, whereas the inaccuracy provides information about the temporal deviation of the timer from a standard time, i.e. a Quality criterion. The inaccuracy can be specified as a percentage.

Activation information within the meaning of the invention means information that provides information about when an event is to take place. These

Information can preferably have a time span which is to be added to a time. The activation information can also contain information relating to an event starting at a second point in time, thus providing information about which or which type of event can be expected.

An event within the meaning of the invention means, in a simple case, the establishment of contact from one of the mobile radio communication devices to the other

Cellular communication device. In a more complex case, the event can also mean information about the type of contact made. Furthermore, the event can also contain information about the communication protocol via which contact is to be made or will be made. The information can also have a communication channel via which communication should take place in the event of an event. The establishment of contact can also include an instruction and / or request to the respective other mobile radio communication device.

Processing the received activation information within the meaning of the invention means evaluating the activation information with regard to the information or information contained therein. The result of processing can be have a time surcharge on a time, preferably on the time at which the activation information was received.

The teaching according to the invention has the advantage that time synchronization is made possible in a mobile radio communication system while at the same time minimizing the energy consumption of the mobile radio communication system. The subject matter of an independent claim relates to a method for operating a mobile radio communication device, the method comprising: sending a first message to a further mobile radio communication device. Receiving a connection request from the further

Cellular communication device. Receiving an indication or a confirmation of a connection between the mobile radio communication device and the further mobile radio communication device. Starting a timer on the first cellular communication device based on the

Receipt of the information or the confirmation of the connection between the mobile radio communication device and the further mobile radio communication device. Sending activation information at a first point in time to the further mobile radio communication device, the

Activation information has information relating to an event starting at a second point in time. And activate the first

Mobile radio communication device at the second point in time, such that the first mobile radio communication device to the second time is set up to send the event to the second cellular communication device.

The teaching according to the invention has the advantage that a time synchronization between mobile radio communication devices is made possible while at the same time minimizing the energy consumption of a mobile radio communication device waiting for information from another mobile radio communication device.

The subject matter of a further independent claim relates to a method for operating a mobile radio communication device, the method comprising: receiving a first message from a further mobile radio communication device. Sending a connection request to the other

Cellular communication device. Receiving an indication or a confirmation of a connection between the mobile radio communication device and the further mobile radio communication device. Starting a timer on the mobile radio communication device based on the receipt of the information or the confirmation of the connection of the mobile radio communication device to the further mobile radio communication device. Receiving activation information from the further mobile radio communication device, wherein the

Activation information has information relating to an event starting at a second point in time. Processing of the received activation information by the Mobile radio communication device such that the mobile radio communication device determines its own event time at which the event of the further mobile radio device is expected by the mobile radio communication device. And activate the mobile radio communication device at its own event time, in such a way that the

Mobile radio communication device is set up at its own event time to receive the event from the further mobile radio communication device.

The subject of a further independent claim relates to a

Mobile radio communication device, the mobile radio communication device being set up to carry out a method according to the invention for operating the mobile radio communication device.

The teaching according to the invention has the advantage that a cellular radio communication device can keep its energy consumption low despite time synchronization with another cellular radio communication device. The subject matter of a further independent claim relates to a motor vehicle having a mobile radio communication device according to the invention.

The teaching according to the invention achieves the advantage that a motor vehicle can be provided which is set up to keep its energy consumption low despite time synchronization with a further mobile radio communication device.

The subject matter of a further independent claim relates to a computer program product for a device according to the invention and / or a motor vehicle according to the invention, wherein the device and / or the motor vehicle can be operated according to any corresponding method according to the invention or the computer program product is set up to control at least one processor that controls the sequence causes at least one step of a method according to the invention. The teaching according to the invention has the advantage that the method can be carried out automatically in a particularly efficient manner.

The subject matter of a further independent claim relates to a data carrier having a computer program product according to the invention.

The teaching according to the invention has the advantage that the method can be applied particularly efficiently to the devices, systems and / or Motor vehicles can be distributed or held available.

Before embodiments of the invention are described in more detail below, it should first be noted that the invention is not limited to the components described or the method steps described. Furthermore, the terminology used does not represent any restriction, but is merely an example. Insofar as the singular is used in the description and the claims, the plural is also included, unless the context explicitly excludes this. If the context does not explicitly exclude this, any procedural steps can be carried out automatically. Corresponding method sections can lead to corresponding device properties and vice versa, so that, unless the context explicitly excludes this, a change of one

Process feature is made possible in a device feature and vice versa.

Further exemplary embodiments of the method according to the invention are explained below.

According to a first exemplary embodiment, the method also has the first message having an advertising packet.

This refinement has the advantage that a conventional and common message for time synchronization can be used and thus the implementation effort can be kept low.

According to a further exemplary embodiment, the method also has that the connection request has a connection request in accordance with a Bluetooth Low Energy Standard.

Thus, in this exemplary embodiment, the mobile radio communication devices are set up to communicate with one another in a Bluetooth mobile radio network according to a Bluetooth low energy standard.

This refinement has the advantage that an up-to-date mobile radio communication standard that can be used well for IOT applications can be used.

According to a further exemplary embodiment, the method also has that the receipt of the information or the confirmation of the connection of the first mobile radio communication device to the second

Mobile radio communication device has a corresponding notice or a corresponding confirmation in accordance with a Bluetooth Low Energy Standard.

This embodiment has the advantage that the protocol of this standard does not have to be changed for this, but can be used unmodified.

According to another exemplary

Embodiment, the method also has that the The start of the first timer and the start of the second timer take place synchronously with one another.

Thus, in this exemplary embodiment, the two timers are time-synchronized with one another.

This refinement has the advantage that a simple possibility can be used to establish time synchronicity between the two mobile radio communication devices.

According to a further exemplary embodiment, the method furthermore has that the first timer and the second timer run synchronously with one another, with a desynchronization rate that is dependent on a first timer of the first mobile radio communication device and a second timer of the second mobile radio communication device.

This refinement has the advantage that the accuracy of the time synchronicity between the two mobile radio communication devices is defined and is therefore known, and excessive desynchronization can thus be counteracted.

According to a further exemplary embodiment, the method also has: the first mobile radio communication device decides at a first point in time that an event should begin at a second point in time. The second point in time is later than the first point in time. And the first point in time is after the start of the first timer. This refinement has the advantage that a mobile radio communication device can tell a further mobile radio communication device a point in time at which it can expect an event. As a result, the further mobile radio communication device does not have to constantly search for an event and can thus be operated in an energy-saving manner.

According to a further exemplary embodiment, the method also has the activation information relating to the event starting at the second point in time having a time offset from the first point in time, from which the second mobile radio communication device can deduce a separate event time of the event to be started.

This refinement has the advantage that the information about the time of the expected event can be passed on to the further mobile radio communication device in a simple manner.

According to a further exemplary embodiment, the method also has that the own event time has a point in time and / or a time period at which the second

Cellular communication device is activated to receive messages from the first cellular communication device.

This refinement has the advantage that, despite a desynchronization rate, the event can be received in an energy-optimized manner. According to a further exemplary embodiment, the method also has that the activation information regarding the event starting at the second point in time includes information regarding the expected event, from which the second mobile radio communication device can infer the event to be waited or to be listened to the activation of the second mobile radio communication device has the consequence.

This embodiment has the advantage that, despite a desynchronization rate, the further

Mobile radio communication device can receive the event in an energy-optimized manner.

According to a further exemplary embodiment, the method further includes activating the second mobile radio communication device at its own event time, activating a receiving capability or a receiving channel of the second mobile radio communication device at its own event time in order to receive the event from the first mobile radio communication device.

Mobile radio communication device can receive the event in an even more energy-optimized manner.

According to a further exemplary embodiment, the method also has that the The first mobile radio communication device or the second mobile radio communication device is set up to generate a time stamp, the time stamp being indicative in order to assign a unique point in time to a future event.

This refinement has the advantage that time synchronization can take place even more precisely. Furthermore, the time synchronization can be carried out in a comprehensible manner.

According to a further exemplary embodiment, the method also has that the mobile radio communication device generating the time stamp is set up to transmit the time stamp to the respective other mobile radio communication device.

This refinement has the advantage that time synchronization can be carried out in an even better traceable manner. According to another exemplary

In an embodiment, the method also has that the time stamp for sending a useful message from one of the two mobile radio communication devices to the respective other of the two mobile radio communication devices takes place via a communication link based on an ultra-wide band (UWB) communication standard.

If the useful message is to be received using a UWB communication standard, this is typically associated with a relatively high energy consumption by the recipient. By a temporal Synchronization between transmitter and receiver makes it possible to deactivate the receiver mobile radio communication device at least temporarily so that the energy consumption of the receiver can be reduced significantly.

The transmitter mobile radio communication device can, for example, be part of a Telestart transmitter (for example a smartphone or a vehicle key) for an access and / or activation function of a vehicle, whereas the receiver

Mobile communication device can be part of a motor vehicle. For example, depending on a received useful message, access to the vehicle can be achieved (for example unlocking the vehicle) and / or a function of the vehicle can be activated (for example starting the drive motor of the vehicle).

The reception period can have a duration of 50% or less, preferably 20% or less, particularly preferably 10% or less, of a period duration, i.e. a time interval between two possible transmission times or the corresponding reception times of useful messages. Furthermore, the receiver can be deactivated in the period between two directly successive reception periods, in particular with regard to the reception of a useful message from the sender. A reliable and energy-efficient reception of useful messages can thus be achieved. This refinement also has the advantage that reliable time synchronization can also be made possible in a simple manner in a UWB without the UWB protocol having to be modified. In addition, this embodiment has the advantage that when using a UWB-based

Cellular communication connection the energy consumption can be significantly reduced. According to another exemplary

In an embodiment, the method furthermore has that the processing of the received activation information is carried out by the second mobile radio communication device based on the time stamp. This configuration has the advantage that a

Time synchronization can be done even more precisely.

According to a further exemplary embodiment, the method also has that the event has time synchronization information by means of which the first timer can be synchronized again with the second timer.

This refinement has the advantage that time synchronization can be maintained more precisely over a longer period of time.

According to a further exemplary embodiment, the method further comprises: activating the first mobile radio communication device at the time of the event, such that the first Mobile radio communication device is set up at the event time to send the event to the second mobile radio communication device.

This refinement has the advantage that the first mobile radio communication device can send the event in a more energy-optimized manner.

The invention thus makes it possible to establish communication between two mobile radio communication devices in a time-synchronous manner in order to be able to communicate with one another in an energy-optimized manner.

The invention will be explained in more detail below with reference to the figures. In these show: FIG. 1 a schematic representation of a first proposed method according to an exemplary embodiment of the invention;

2 shows a schematic illustration of a further proposed method according to a further exemplary embodiment of the invention;

3 shows a schematic representation of a further proposed method according to a further exemplary embodiment of the invention;

4 shows a schematic representation of a further proposed method according to a further exemplary embodiment of the invention;

5 shows a schematic representation of a further proposed method according to a further exemplary embodiment of the invention; and 6 shows a schematic representation of a further proposed method according to a further exemplary embodiment of the invention.

1 shows a schematic representation of a first proposed method according to an exemplary embodiment of the invention.

1 shows a schematic representation of a. The subject matter of the main claim relates to a method for operating a

Mobile radio communication system, the method comprising: sending a first message ADV_INF from a first mobile radio communication device device 1 (device 1) to a second mobile radio communication device device 2 (device 2). Sending a connection request VERBINDUNG_ANF (CONNECT_REQ) from the second mobile radio communication device device 2 (device 2) to the first mobile radio communication device device 1 (device 1). Receipt of a message or a confirmation of a connection between the first mobile radio communication device device 1 (device 1) and the second mobile radio communication device device 2 (device 2), through the first mobile radio communication device device 1 (device 1) and through the second mobile radio communication device device 2 (device 2) . Starting a first timer TI on the first mobile radio communication device device 1 (device 1), based on the receipt of the information or the confirmation of the connection of the first mobile radio communication device device 1 (device 1) with the second mobile radio communication device device 2 (device 2). Starting a second timer T2 on the second mobile radio communication device device 2 (device 2), based on the receipt of the information or the confirmation of the connection of the first mobile radio communication device device 1 (device 1) to the second mobile radio communication device device 2 (device 2). Sending of activation information Aktlnf from the first mobile radio communication device device 1 (device 1) to the second mobile radio communication device device 2 (device 2) at a first point in time t1, the activation information item Aktlnf having information relating to an event beginning at a second point in time t2 . Processing of the received activation information Aktlnf by the second mobile radio communication device device 2 (device 2) in such a way that the second mobile radio communication device device 2 (device 2) determines its own event time EventT (eventT) at which the event event (event) from the second mobile radio communication device device 2 (Device 2) is expected. And activate the second mobile radio communication device device 2 (device 2) at its own event time EventT (eventT), such that the second mobile radio communication device device 2 (device 2) is set up at its own event time EventT (eventT), the event Event (event) from the first mobile radio communication device device 1 (device 1) to receive. 2 shows a schematic representation of a further proposed method according to a further exemplary embodiment of the invention.

2 shows a schematic representation of a method according to FIG. 1, the method further comprising: deciding at a first point in time t1 that an event should begin at a second point in time t2, by the first

Mobile radio communication device device 1 (device 1). The second point in time t2 is later than the first point in time t1. And the first point in time tl occurs after the start of the first timer Tl.

The activation information Aktlnf has a time offset dt with respect to the event beginning at the second point in time t2 compared to the first point in time tl, from which the second mobile radio communication device device 2 (device 2) assigns its own event time to eventT (eventT) of beginning event event (event) can be closed.

3 shows a schematic illustration of a further proposed method according to a further exemplary embodiment of the invention.

3 shows a schematic representation of a method according to FIG. 2, the method further comprising: activating the first

Mobile radio communication device device 1 (device 1) at the event time EventT (eventT), such that the first mobile radio communication device device 1 (device 1) at the event time EventT (eventT) it is set up to send the event Event (event) to the second mobile radio communication device device 2 (device 2).

4 shows a schematic illustration of a further proposed method according to a further exemplary embodiment of the invention.

4 shows a schematic representation of a method according to FIG. 3, the first message ADV_INF having an advertising packet.

The connection request VERBINDUNG_ANF (CONNECT_REQ) also has a connection request in accordance with a Bluetooth Low Energy Standard.

In addition, the receipt of the information or the confirmation of the connection of the first mobile radio communication device device 1 (device 1) to the second mobile radio communication device device 2 (device 2) has a corresponding message or a corresponding confirmation in accordance with a Bluetooth low energy standard.

The start of the first timer TI and the start of the second timer T2 take place synchronously with one another.

The first timer TI and the second timer T2 run synchronously with one another, at a desynchronization rate that is dependent on one another, from a first quartz timer 1 (not shown in FIG. 4 for the sake of clarity) of the first mobile radio communication device device 1 (device 1) and a second quartz timer 2 (not shown in Fig. 4 for the sake of clarity) of the second mobile radio communication device device 2 (device 2).

The two timers thus desynchronize with one another, the more the time t0 (not shown in FIG. 4 for the sake of clarity) has passed. Here tO indicates the time-synchronous start of the two timers TI, T2.

Depending on the quality of the crystals installed in the mobile radio communication devices, the two timers TI and T2 should either be resynchronized earlier - with cheap crystals with a low quality, thus higher desynchronization rate - or correspondingly later - with higher quality crystals with high quality, thus lower desynchronization rate.

To resynchronize the two timers TI, T2, at least the first part of the method should be carried out again, i.e.

Sending the first message ADV_INF from the first mobile radio communication device device 1 (device 1) to the second mobile radio communication device device 2 (device 2). Sending a connection request VERBINDUNG ANF (CONNECT REQ) from the second mobile radio communication device device 2 (device 2) to the first

Mobile radio communication device device 1 (device 1). Receiving the notification or the confirmation of the connection of the first

Mobile radio communication device device 1 (device 1) with the second mobile radio communication device device 2 (device 2), through the first mobile radio communication device device 1 (device 1) and through the second Mobile radio communication device device 2 (device 2). Starting the first timer TI on the first mobile radio communication device device 1 (device 1) based on the receipt of the information or the confirmation of the connection of the first mobile radio communication device device 1 (device 1) to the second mobile radio communication device device 2 (device 2). And start the second timer T2 on the second mobile radio communication device device 2 (device 2) based on the receipt of the information or the confirmation of the connection of the first mobile radio communication device device 1 (device 1) to the second mobile radio communication device device 2 (device 2).

Furthermore, the activation information item Aktlnf has a time offset dt with respect to the event beginning at the second time t2 compared to the first time t1. From this, the second mobile radio communication device device 2 (device 2) can deduce its own event time EventT (eventT) of the event that is about to begin.

It can thus be established at a point in time t1 that the event should take place at a point in time t2.

The result of the first time tl plus a surcharge in the form of the time offset dt can therefore be specified as the event time t2, as: t2 = tl + dt. Thus, at time tl it can be determined that the time Tl * + dt continues to the second Cellular communication device device 2 (device 2) is to be passed on.

The second mobile radio communication device device 2 (device 2) then receives the time T2 * as the event time.

+ dt, since TI and T2 are viewed as time-synchronous with one another. The own event time EventT (eventT) for the second mobile radio communication device device 2 (Device 2) can thus be determined as EventT (eventT) =

T2 * + dt.

If, for example, the first mobile radio communication device device 1 (device 1) sends the event start information with TI * + dt as activation information Aktlnf to the second mobile radio communication device device 2 (device 2) at time tl, it may be that this activation information Aktlnf is not received. If this activation information Aktlnf is then sent again at a later point in time tl '<t2, the event start information still looks the same: Tl * + dt. Tl * has not changed, although the time dt' = tl '- tl has now passed. Because both Tl * and dt are now fixed for the transmission of the event information. In the next successful transmission of the event start information, the second mobile radio communication device device 2 (device 2) can still expect the event start, i.e. its own event time EventT (eventT), at the same point in time, since the event time is still Tl * + dt and can therefore be calculated back to determine the time T2 * and from this the own event time EventT (eventT). Thus the event becomes at the time of the timer own event time EventT (eventT) = T2 * + dt = TI * + dt expected. Only the de-synchronization will be advanced. Thus, for example, a time window of the second mobile radio communication device device 2 (device 2) can be set around its own event time EventT (eventT), which should be greater with regard to de-synchronization, the closer the reception of TI * + dt to its own event time EventT (eventT) lies.

The own event time EventT (eventT) has a point in time and / or a period in which the event Event (event) should begin.

Furthermore, the activation information Aktlnf with regard to the event beginning at the second point in time t2 has information regarding the expected event event (event) from which the second mobile radio communication device device 2 (device 2) points to the waiting or listening Event Event (event) can be closed, which results in the activation of the second mobile radio communication device device 2 (device 2).

Activating the second

Mobile radio communication device device 2 (device 2) has at its own event time EventT (eventT), an activation of a reception capability or a receiving channel of the second mobile radio communication device device 2 (device 2) at its own event time EventT (eventT) to activate the event Event (event) from the first mobile radio communication device device

1 (Device 1).

5 shows a schematic representation of a further proposed method according to a further exemplary embodiment of the invention.

5 shows a schematic representation of a method for operating a

Mobile radio communication device device 1 (device 1), the method comprising: sending a first message ADV_INF to another

Mobile radio communication device device 2 (device 2) (not shown in FIG. 5). Receipt of a connection request VERBINDUNG_ANF (CONNECT_REQ) from the further mobile radio communication device device 2 (device 2). Receiving an indication or a confirmation of a connection between the mobile radio communication device device 1 (device 1) and the further mobile radio communication device device

2 (Device 2). Starting a timer TI on the first mobile radio communication device device 1 (device 1) based on the receipt of the information or the confirmation of the connection of the

Mobile radio communication device device 1 (device 1) with the further mobile radio communication device device 2 (device 2). Sending activation information Aktlnf at a first point in time t1 to the further mobile radio communication device device 2 (device 2), the activation information Aktlnf information relating to an item beginning at a second point in time t2 Event has event (event). And activate the first mobile radio communication device device 1 (device 1) at the second time t2, such that the first mobile radio communication device device 1 (device 1) is set up at the second time t2, the event event (event) at the second

Mobile radio communication device device 2 (Device 2) to send.

6 shows a schematic representation of a further proposed method according to a further exemplary embodiment of the invention.

6 shows a schematic representation of a method for operating a

Mobile radio communication device device 2 (device 2), the method comprising: receiving a first message ADV_INF from another

Mobile radio communication device device 1 (device 1) (not shown in FIG. 6). Sending a connection request VERBINDUNG_ANF (CONNECT_REQ) to the further mobile radio communication device device 1 (device 1). Receiving a notice or a confirmation of a connection of the

Mobile radio communication device device 2 (device 2) with the further mobile radio communication device device 1 (device 1). Starting a timer T2 on the mobile radio communication device device 2 (device 2) based on the receipt of the message or the confirmation of the connection of the

Mobile radio communication device device 2 (device 2) with the further mobile radio communication device device

1 (device 1). Receiving activation information Aktlnf from the further mobile radio communication device device 1 (device 1), wherein the

Activation information Aktlnf has information relating to an event beginning at a second point in time t2. Processing of the received activation information Aktlnf by the mobile radio communication device device 2 (device 2) such that the mobile radio communication device device

2 (Device 2) determines its own event time, EventT (eventT), at which the event Event (event) of the further mobile radio device device 1 (device 1) is expected by the mobile radio communication device device 2 (device 2). And activate the

Mobile radio communication device device 2 (device 2) at its own event time EventT (eventT), in such a way that the mobile radio communication device device 2 (device 2) is set up at its own event time EventT (eventT), the event event (event) from the further mobile radio communication device device 1 (Device 1) to be received.

The dashed lines in the figures indicate that at the corresponding time, the corresponding mobile radio communication device device 1 (device 1), device 2 (device 2) is deactivated or can be deactivated in order to minimize the consumption of electrical energy. The inventive idea can be summarized as follows. Three methods, a related mobile radio communication device and a motor vehicle are provided with which it can be possible to establish and maintain a reliable time synchronization in a simple manner. Due to the high reliability of the time synchronization, the

Mobile radio communication devices device 1 (device 1), device 2 (device 2) communicating with one another with minimal energy.

For time synchronization, information can be used which is present at the same time on both mobile radio communication devices device 1 (device 1), device 2 (device 2). At this point in time, a timer TI, T2 is started on both mobile radio communication devices device 1 (device 1), device 2 (device 2) so that they run synchronously. Now one of the two can

Cellular communication devices Device 1 (Device 1), Device 2 (Device 2) of the other

Mobile radio communication device device 1 (device 1), device 2 (device 2) allow a point in time at which it can expect an event (event). This can be, for example, a point in time that can lie a certain time after the two mobile radio communication devices device 1 (device 1), device 2 (device 2) have been reconnected.

This can take place in particular by means of mobile radio communication in accordance with a Bluetooth Low Energy Standard (BLE). If two mobile radio communication devices device 1 (device 1), device 2 (device 2) are paired with one another, the method can proceed as follows:

Receipt of an advertising packet by a second cellular radio communication device device 2 (device 2).

Sending a connection request to the first mobile radio communication device device 1 (device 1), according to a BLE standard.

At this point in time, an indication of connection is sent to the respective other mobile radio communication device device 1 (device

1), device 2 (device 2) sent, according to a BLE standard.

As soon as these connection indications are received, the corresponding timer starts in each case on the corresponding mobile radio communication device device 1 (device 1), device 2 (device 2): TI and T2.

If the first mobile radio communication device device 1 (device 1) decides at time t1 that an event should take place at a second time t2, it sends it to the other mobile radio communication device device 2 (device

2) an indication that the event will take place at the timer time Tl * + dt. Since T1 and T2 are synchronized with one another, the time synchronization is also retained in the event that further transmissions of the timer time instant T1 * + dt are required. The second Mobile radio communication device device 2 (device 2) now expects the event to take place at the timer time T2 * + dt.

A re-synchronization, i.e. a synchronization update, can be carried out using a few BLE events, for example. Events can be used that are triggered at the same time on both mobile radio communication devices device 1 (device 1), device 2 (device 2), and thus take place at the same time. For example, the re-synchronization can take place with a connection parameter update procedure (connection parameters update procedure) in which both timers TI and T2 are re-synchronized to one another again.

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List of reference symbols

ADV_INF first message

Device 1 first mobile radio communication device Device 2 second mobile radio communication device CONNECTION ANF Connection request

Current activation information quartz 1 first timer quartz 2 second timer TI first timer or its current time

T2 second timer or its current time

TI * Timer Time of the first timer at time tl

T2 At the timer instant Tl * of the first timer, the timer instant of the second timer tl first instant of the first

Mobile radio communication device t2 second time of the first

Mobile radio communication device dt time offset compared to the first

time

Event event

EventT own event time of the event event for the second mobile radio communication device

Motor vehicle

Claims

1. Procedure for operating a

Mobile radio communication system, the method comprising:

Sending a first message (ADV INF) from a first mobile radio communication device (device 1) to a second mobile radio communication device (device 2),

Send a connection request (VERBINDUNG_ANF (CONNECT REQ)) from the second

Mobile radio communication device (device 2) to the first mobile radio communication device (device 1), receiving an indication or confirmation of a connection between the first mobile radio communication device (device 1) and the second mobile radio communication device (device 2), through the first mobile radio communication device (device 1) and through the second mobile radio communication device (device 2),

Starting a first timer (TI) on the first mobile radio communication device (device 1) based on the receipt of the information or the confirmation of the connection of the first mobile radio communication device (device 1) to the second mobile radio communication device (device 2) Starting a second timer (T2) on the second mobile radio communication device (device 2) based on the receipt of the information or the confirmation of the connection of the first mobile radio communication device (device 1) to the second mobile radio communication device (device 2),

Sending activation information (Aktlnf) from the first mobile radio communication device (device 1) to the second mobile radio communication device (device 2) at a first point in time (tl), the activation information item (Aktlnf) being information relating to an event (t2) beginning at a second point in time (t2). Event), processing of the received activation information (Aktlnf) by the second

Mobile radio communication device (device 2) such that the second mobile radio communication device (device 2) determines its own event time (EventT) at which the event (event) is expected by the second mobile radio communication device (device 2), and

Activate the second mobile radio communication device (device 2) at its own event time (EventT), such that the second mobile radio communication device (device 2) is set up at its own event time (EventT) to assign the event (event) from the first mobile radio communication device (device 1) receive.

2. The method of claim 1, wherein the first message (ADV INF) comprises an advertising packet.

3. The method according to claim 1 or 2, wherein the connection request (VERBINDUNG_ANF (CONNECT_REQ)) comprises a connection request according to a Bluetooth Low Energy Standard.

4. The method according to any one of the preceding claims, wherein the start of the first timer (TI) and the start of the second timer (T2) take place synchronously with one another.

5. The method according to any one of the preceding claims, wherein the first timer (TI) and the second timer (T2) run synchronously with one another, with a desynchronization rate that is dependent on a first timer (quartz 1) of the first mobile radio communication device (device 1) and a second timer (quartz 2) of the second mobile radio communication device (device 2).

6. The method according to any one of the preceding claims, the method further comprising: deciding at a first point in time (t1) that an event should begin at a second point in time (t2) by the first Mobile radio communication device (device 1), wherein the second point in time (t2) is after the first point in time (tl), and wherein the first point in time (tl) is after the start of the first timer (Tl).

7. The method according to any one of the preceding claims, wherein the activation information (Aktlnf) with respect to the event starting at the second time (12) has a time offset (dt) compared to the first time (tl), from which by the second Mobile radio communication device (device 2) can be closed on its own event time (EventT) of the beginning event (Event).

8. The method of any one of the preceding claims, wherein activating the second

Mobile radio communication device (device 2) at its own event time (EventT), an activation of a receiving capability or a receiving channel of the second

Mobile radio communication device (device 2) at its own event time (EventT) to the event (Event) from the first

Mobile radio communication device (device 1) to receive.

9. The method according to any one of the preceding claims, wherein the event (event) is a

Has time synchronization information, by means of which a renewed synchronization of the first timer (TI) with the second timer (T2) can be undertaken.

10. The method of any one of the preceding claims, the method further comprising:

Activation of the first cellular communication device

(Device 1) at the event time (12) such that the first mobile radio communication device (device 1) is set up at the event time (t2) to send the event (event) to the second mobile radio communication device (device 2).

11. The method according to any one of the preceding claims, wherein the first mobile radio communication device (device 1) or the second mobile radio communication device (device 2) is set up to generate a time stamp, the time stamp being indicative to assign a unique point in time to a future event.

12. The method of claim 11, wherein processing the received activation information

(Aktlnf) through the second

Cellular communication device (device 2) takes place based on the time stamp, preferably based on the time stamp of the first mobile radio communication device (device 1).

13. The method according to any one of the preceding claims 11 or 12, wherein the time stamp for sending a useful message from one of the two mobile radio communication devices to the respective other of the two mobile radio communication devices takes place via a communication link based on an ultra-wide band communication standard.

14. A method for operating a mobile radio communication device (device 1), the method comprising:

Sending a first message (ADV INF) to a further mobile radio communication device (device 2),

Receiving a connection request (VERBINDUNG_ANF (CONNECT_REQ)) from the further mobile radio communication device (device 2), receiving a message or a confirmation of a connection of the

Mobile radio communication device (device 1) with the further mobile radio communication device (device 2),

Starting a timer (TI) on the first mobile radio communication device (device 1) based on the receipt of the information or the confirmation of the connection of the mobile radio communication device (device 1) with the further mobile radio communication device (device 2),

Sending activation information (Aktlnf) at a first point in time (tl) to the further mobile radio communication device (device 2), the activation information item (Aktlnf) comprising information relating to an event (event) starting at a second point in time (t2), and activating the first Mobile radio communication device (device 1) at the second point in time (t2), such that the first mobile radio communication device (device 1) is set up at the second point in time (12) to send the event (event) to the second mobile radio communication device (device 2).

15. Procedure for operating a

Mobile radio communication device (device 2), the method comprising:

Receiving a first message (ADV INF) from a further mobile radio communication device (device 1),

Sending a connection request (VERBINDUNG_ANF (CONNECT_REQ)) to the other

Mobile radio communication device (device 1), receiving a message or a confirmation of a connection of the

Cellular communication device (device 2) with the further mobile radio communication device (device 1),

Starting a timer (T2) on the mobile radio communication device (device 2) based on the receipt of the information or the confirmation of the connection of the mobile radio communication device (device 2) to the further mobile radio communication device (device 1),

Receiving activation information (Aktlnf) from the further mobile radio communication device (device 1), the activation information (Aktlnf) comprising information relating to an event (event) starting at a second point in time (12),

Processing of the received activation information (Aktlnf) by the mobile radio communication device (device 2) such that the

Mobile radio communication device (device 2) determines its own event time (EventT) at which the event (event) of the further mobile radio device (device 1) is expected by the mobile radio communication device (device 2), and activating the mobile radio communication device (device 2) at its own event time ( EventT) in such a way that the

Mobile radio communication device (device 2) is set up at its own event time (EventT), the event (event) from the further Mobile radio communication device (device 1) to receive.

16. Mobile radio communication device (device 1, device 2), wherein the

Mobile radio communication device (device 1, device 2) is set up to carry out a method according to any one of claims 14 or 15.

17. Motor vehicle (motor vehicle), having a mobile radio communication device (device 1, device 2), according to claim 16.

18. Computer program product for controlling at least one processor which effects the execution of at least one step of a method according to any one of the preceding claims 1 to 15.

19. Data carrier having a computer program product according to claim 18.