METHOD AND DEVICE FOR COMMUNICATION BETWEEN A VEHICLE AND A PUBLIC LAND RADIO NETWORK

Description

technical field

[0001] The invention relates to a method and device for communication between a vehicle and a public terrestrial mobile network, for example a 4G or 5G cellular network. The invention also relates to a method and device for optimizing energy consumption to maintain a connection between the vehicle and the network for a specified duration. Technological background

[0002] Modern vehicles are equipped with one or more devices that require a constant connection to a network, such as a wireless cellular network. These devices include, for example, electronic control units (ECUs), also known as electronic control units (ECUs), or telematics control units (TCUs). These ECUs contain one or more software programs that run to perform their assigned functions. Software updates are sometimes necessary, for example, to improve a function or correct an error, also called a "bug" in computer science. These ECUs or units also allow information to be sent to servers, emergency services, or data centers belonging to vehicle manufacturers or automotive parts suppliers.

[0003] These data exchanges are, for example, carried out over the air, using a technology called OTA (over-the-air) for downloading updates. This technology relies on one or more public terrestrial mobile networks in the same way as all cellular communications.

[0004] The communications established between a vehicle and the network consume energy, particularly for the vehicle itself, whose electrical power is supplied by one or more batteries. The amount of electrical energy available in the vehicle is limited, especially when the vehicle is in a situation where the battery is not charging.

[0005] Maintaining communications between the vehicle and the network can thus deplete the amount of energy available in the vehicle, which can prove problematic when, for example, the vehicle is not used for a long period and the vehicle battery cannot be recharged.

[0006] WO 2018 / 225990 A1 discloses a method for controlling the operating mode of an electronic device to save energy, the method being implemented by a server in a wireless communication network. Summary of the invention

[0007] One object of the present invention is to optimize communications between a vehicle and a terrestrial mobile network.

[0008] Another object of the present invention is to optimize the energy consumption of the vehicle by ensuring the maintenance of a connection with the terrestrial mobile network.

[0009] According to a first aspect, the invention relates to a method of communication between a vehicle's communication system and a public terrestrial mobile network, the vehicle being stationary in a cell of the network, the method being implemented by the network, the method comprising the following steps: reception of a first piece of information representing the vehicle's electrical consumption; reception of a second piece of information representing the amount of electricity available in the vehicle; reception of a third piece of information representing the objective of maintaining a connection between the communication system and the network for a specified period; determination of at least one energy saving mode to be allocated to the vehicle's communication system based on the first, second, and third pieces of information; transmission, to the vehicle's communication system, of an instruction to switch to at least one specified energy saving mode.

[0010] The determination of at least one energy saving mode includes the selection of an energy saving profile from a plurality of energy saving profiles, each profile in said plurality being associated with a set of applications and / or services to be kept in operation with a set of associated communication parameters, said set of communication parameters including: - a data exchange frequency; and / or - a data packet size.

[0011] According to one variant, the determination of at least one energy saving mode includes a selection of a mechanism for putting the vehicle's communication system to sleep at regular intervals of determined duration from among a plurality of mechanisms supported by the network.

[0012] According to another variant, the plurality of mechanisms includes: a power saving mode mechanism, called PSM; a discontinuous reception mechanism, called DRX; an extended discontinuous reception mechanism, called eDRX; a continuous connected-mode reception mechanism, called CDRX.

[0013] According to a further variant, the plurality of energy saving profiles includes a profile for which only one or more emergency services are kept in operation.

[0014] According to another variant, the selection of an energy saving profile is based on a virtual image of the communication system of said vehicle recorded in the network.

[0015] According to a second aspect, the invention relates to a device of the public terrestrial mobile network configured to communicate with a vehicle communication system, the device comprising a memory associated with a processor configured for the implementation of the steps of the process according to the first aspect of the invention.

[0016] According to a third aspect, the invention relates to a communication system comprising a device as described above according to the second aspect of the invention and at least one vehicle connected to the public terrestrial mobile network via a wireless link.

[0017] According to a fourth aspect, the invention relates to a computer program which includes instructions adapted for carrying out the steps of the process according to the first aspect of the invention, in particular when the computer program is executed by at least one processor.

[0018] Such a computer program can use any programming language, and be in the form of source code, object code, or an intermediate form between source code and object code, such as in a partially compiled form, or in any other desirable form. Brief description of the figures

[0019] Other features and advantages of the invention will become apparent from the description of the non-limiting embodiments of the invention below, with reference to figures 1 to 3 attached, on which: [ Fig. 1 ] schematically illustrates a communication environment between a vehicle and a public terrestrial mobile network infrastructure, according to a particular embodiment of the present invention; Fig. 2 ] schematically illustrates a communication device of the network of the figure 1 , according to a particular embodiment of the present invention; [ Fig. 3 ] illustrates a flowchart of the different stages of a communication process between the vehicle and the figure 1 and the public terrestrial mobile network of the figure 1 , according to a particular embodiment of the present invention. Description of the implementation methods

[0020] A method and device for communication between a vehicle's communication system and a public terrestrial mobile network will now be described in what follows, with joint reference to figures 1 to 3 The same elements are identified with the same reference symbols throughout the description that follows.

[0021] According to a particular and non-limiting embodiment of the invention, a communication method between a vehicle's communication system and a public land mobile network comprises receiving first information representing the vehicle's current power consumption, second information representing the amount of electricity available in the vehicle, for example, in the vehicle's battery, and third information representing the desired duration for which the vehicle wishes to remain connected to the network. Based on the first, second, and third pieces of information, the network determines which power-saving mode should be allocated to the vehicle's communication system so that it can maintain a connection with the network for the desired duration. The network then transmits to the vehicle which power-saving mode the communication system should switch to.

[0022] When a vehicle communicates information about its energy consumption, energy resources, and connection duration goals to the grid, the grid can implement appropriate mechanisms to meet the vehicle's connection requirements. This optimizes the vehicle's available energy resources to maintain a connection with the grid.

[0023] Although the description below relates to a method and device for communication between a vehicle's communication system and a public terrestrial mobile network, the invention is not limited to such an implementation. The invention extends to a method and device for communication between any mobile communication device (e.g., a smartphone, tablet, or connected object) and any mobile network.

[0024] [ Fig. 1 ] schematically illustrates a communication environment 1 between a vehicle 10 and a public terrestrial mobile network infrastructure, according to a particular and non-limiting embodiment of the present invention.

[0025] There figure 1 This illustrates a parked vehicle 10, for example in a parking space in a car park or garage, communicating with one or more remote servers or the "cloud" 100 (or in French "nuage") through one or more communication devices 110 such as a cellular network relay antenna, forming part of the infrastructure of the public terrestrial mobile network. The public terrestrial mobile network advantageously corresponds to a cellular type network, for example a fourth-generation or fifth-generation 3GPP (from the English "3rd Generation Partnership Project" or in French "Projet de partenariat de 3ème génération") network, referred to as 3GPP 4G or 5G, respectively.

[0026] Vehicle 10, for example, is part of a group of vehicles 10, 11, 12 that are stopped for a set period of time, for example a few days, weeks or months.

[0027] Vehicle 10 includes, in particular, a communication system powered by an electrical battery of a determined capacity. The communication system includes, for example, a communication device, such as a TCU, connected to one or more computers of the vehicle 10's embedded system. This computer or these computers correspond, for example, to computers that transmit data (for example, from sensors of vehicle 10) to one or more servers in the "cloud" 100 via a wireless connection conforming to the LTE (Long-Term Evolution), LTE-Advanced, or 3GPP 5G standard and / or receive data from this or these servers.

[0028] The quantity of electricity is expressed in ampere-hours (Ah, a unit of electric charge; 1 Ah corresponds to the amount of electricity flowing through a cross-section of a conductor carrying a current of 1 ampere for 1 hour). The quantity of electrical energy is expressed in watt-hours (or kilowatt-hours, kWh; 1 kWh corresponds to the amount of energy consumed by a 1000-watt appliance for 1 hour). It is possible to convert between the two units using, for example, the nominal voltage V across the terminals of the vehicle's battery, where Ah * V => Wh.

[0029] The battery's state of charge (SOC) or depth of discharge (DOD) indicates its charge level. This information is obtained, for example, through a battery management system (BMS) connected to the battery or by a computer that receives battery parameters to determine the SOC.

[0030] The elements forming the communication system are, for example, connected to each other via a wired network, for example a CAN type network (from the English "Controller Area Network" or in French "Réseau de contrôlers"), CAN FD (from the English "Controller Area Network Flexible Data-Rate" or in French "Réseau de contrôlers à débit de données flexible"), FlexRay (according to the ISO 17458 standard) or Ethernet (according to the ISO / IEC 802.3 standard).

[0031] The vehicle 10 is advantageously stationary, or nearly stationary, within a cell of the mobile network with which one or more communications are established. The cell corresponds to a geographical coverage area of ​​a communication antenna (also called a base station), for example antenna 110, enabling radio communications between the vehicle 10 and the network infrastructure of the mobile network.

[0032] In one specific implementation, the mobile network is a 3GPP 5G network. In this example, the network is divided into network slices based on Software-Defined Networking (SDN) and / or Network Function Virtualization (NFV) technologies. A network slice corresponds to a form of virtual network architecture, that is, a logical instance of the terrestrial mobile network. Slicing a network allows the creation of multiple virtual networks on a shared physical infrastructure.Each network slice is allocated a set of dedicated resources by the network operator for specific use by a given customer (e.g., an automotive supplier) or for a particular device, such as the vehicle's communication system. This segmentation of the 3GPP 5G public terrestrial mobile network is described and defined in the specification document entitled "5G; System Architecture for the 5G System," referenced as ETSI TS 123 501 version 15.2.0 and published in June 2018. In one variant, the vehicle accesses one or more network slices to access the services associated with those slices, with a specific service being associated with each slice. Each network slice corresponds to an end-to-end virtual network, from the vehicle to the physical or virtual machine in the cloud providing the associated service.

[0033] In a first operation, the network receives, for example, one or more servers in the "cloud" 100, a first piece of information representing the current electrical consumption of vehicle 10, a second piece of information representing the amount of electricity available in vehicle 10, and a third piece of information representing the objective of maintaining a connection between the communication system of vehicle 10 and the network for a specified duration. This information is transmitted by vehicle 10 via a wireless link, for example, at the request of the network, or at the initiative of the communication system of vehicle 10, either periodically or aperiodically. The wireless link is an OTA (Over-The-Air) type link, for example, and conforms to a wireless communication standard, such as LTE, LTE-Advance, or 3GPP 5G.

[0034] The first piece of information corresponds, for example, to the amount of electricity supplied by the battery at a given moment, this first piece of information being obtained, for example, from the BMS system associated with the battery.

[0035] The second piece of information corresponds, for example, to the amount of electricity remaining in the battery at the moment the first piece of information was provided, this second piece of information corresponding, for example, to the state of charge SOC or the depth of discharge DOD obtained, for example, from the BMS system associated with the battery.

[0036] The third piece of information corresponds, for example, to the duration (expressed, for instance, in hours or days) for which vehicle 10 wishes to maintain communications with the mobile network. This third piece of information corresponds, for example, to a duration determined according to the environment and the vehicle's situation. This duration is, for example, predetermined, i.e., stored in the communication system's memory. In another variant, this duration is a configurable value, for example, a value entered by a vehicle user via a human-machine interface (HMI).

[0037] In a second operation, the network determines one or more energy saving modes to allocate to the vehicle 10 communication system based on the first, second and third information received.

[0038] According to a first specific embodiment, a first energy-saving mode corresponding to a sleep mode mechanism for the vehicle 10 communication system is determined. This mechanism, allocated to communications between the vehicle 10 communication system and the network, is advantageously selected from a list of available mechanisms compatible with the mobile network communication standard (e.g., LTE, LTE-Advanced, or 3GPP 5G). The mechanism is selected based on the parameters provided by the vehicle 10 and corresponding to the first, second, and third pieces of information received. The selected mechanism corresponds, for example, to one of the following mechanisms: PSM mechanism (from the English "Power Saving Mode" or in French "Mode d'économie d'énergie"): this mechanism allows the radio of the vehicle's radio system 10 to be switched off for an extended period; according to this mechanism, the radio system remains listening to the "paging" channel (or "tele-warning" in French) once it has entered a rest or standby state for a determined active time characterized by a timer named T3324; once this timer has expired, the vehicle's radio system 10 is no longer reachable by the network or the "cloud" 100 since the radio of the radio system is deactivated for a duration corresponding to the timer named T3412; the timers T3324 and T3412 are, for example, determined by the network or the "cloud" 100;DRX mechanism (from the English "Discontinuous Reception" or in French "Réception discontinue"): this mechanism allows the radio of the vehicle's radio system 10 to be switched off periodically in order to monitor the PDCCH channel (from the English "Physical Downlink Control Channel" or in French "canal de commande physique descendu"), according to a cycle called the DRX cycle which corresponds to a period during which the radio module is at rest ("DRX sleep" in English) alternating with a period of activity ("DRX Active State" in English); the values ​​of the DRX cycle vary between 2 ms and 640 ms, with the value of the active period between 1 and 200 ms; eDRX mechanism (from the English "Extended Discontinuous Reception" or in French "Réception discontinue tendue"): this mechanism corresponds to an extended mode of the DRX mechanism, i.e. that the period of inactivity of the radio module can be extended compared to that of the DRX mechanism;According to this mechanism, the "paging" interval (or "tele-warning" in French) can be extended to values ​​between 5.12 seconds and 2621.44 seconds, that is to say that the radio system of vehicle 10 can be in a rest or standby state during the "paging" interval, the radio module of the radio system waking up at each end of the interval to listen to the PDCCH logical channel (from the English "Physical Downlink Control Channel" or in French "canal de commande physique descendant") on which the RRC (from the English "Radio Resource Control" or in French "Contrôle de ressource radio") "paging" message is issued by the "cloud" server 100 to notify vehicle 10 that data is waiting to be transmitted to its radio system;CDRX mechanism (from the English "Connected Mode Discontinuous Reception" or in French "Réception discontinue en mode connecté"): this mechanism corresponds to a connected mode of the DRX mechanism, that is to say that according to the CDRX mechanism, the short DRX cycle is optional and if it is not activated only the long DRX cycle is executed.

[0039] Of course, the sleep mechanisms in the list above are provided as examples and the sleep mechanisms of the vehicle communication system 10 are not limited to the examples above.

[0040] The examples in the list above are mechanisms known to those skilled in the art and compliant with LTE standards. These mechanisms are described, for example, in the book written by Olof Liberg et al. and entitled "Cellular Internet of Things: from massive deployments to critical 5G".

[0041] According to a second specific embodiment, a second energy-saving mode corresponding to an energy-saving profile allocated to the communication system of vehicle 10 is determined. The allocated profile is, for example, selected from a list of predetermined energy-saving profiles. Each profile corresponds, for example, to a reduced list of applications or services that are kept running, with associated communication parameters; the list is reduced the greater the energy savings to be achieved. The profile is advantageously selected based on the parameters provided by vehicle 10 and corresponding to the first, second, and third pieces of information received.

[0042] As an example, the list of energy saving profiles includes the following profiles, but is not limited to the profiles listed below: low power consumption profile: according to this profile, a first restricted set of applications remain executed, a second restricted set of services are maintained such as for example vehicle location services 10, "push" type services, emergency services (automatic alert of a security service in case of accident or breakdown for example) with associated communication parameters such as a low frequency of data exchange between the network and the vehicle 10 (for example only every 1 minute) and a reduced size of the data packets exchanged; according to a variant, the communication parameters associated with each service or application vary from one service (respectively one application) to another (respectively to another);Very low power consumption profile: According to this profile, the number of applications run and services maintained is reduced compared to the low power consumption profile, with associated communication parameters configured to reduce consumption by, for example, decreasing the data exchange frequency (e.g., only every 10 minutes) and / or reducing the size of the data packets exchanged; according to a variant, the communication parameters associated with each service or application vary from one service (or application) to another (or application); Extreme low power consumption profile: According to this profile, only the applications or services related to the emergency system(s) are maintained with a very low data exchange frequency (e.g., only every 30 minutes) and a very small data packet size.

[0043] According to one embodiment, the profile best suited to the requirements and capacity of the vehicle (defined by the first, second and third information) is determined by the network on the basis of a virtual image of the communication system of the vehicle 10, such a virtual image corresponding for example to a copy of the applications and services provided by the vehicle 10, a copy of the hardware and software parameters of the vehicle 10 on a network slice of the cloud 100. According to this embodiment, the network or the cloud is able to test the different profiles and different associated communication parameters allowing to respond to the request of the vehicle 10 in terms of duration of maintenance of communication with the network on the basis of information of electricity consumption and state of charge before determining the optimum profile.

[0044] According to a third embodiment, the network combines a sleep mechanism (as described in the first embodiment) of the radio system with a power saving profile (as described in the second embodiment) to respond to the request of vehicle 10 in terms of duration of communication with the network based on electricity consumption and state of charge information.

[0045] According to another embodiment, the first and second information is periodically transmitted to the network so that the network can adapt the sleep mechanism and / or the energy saving profile to the actual electricity consumption of the vehicle 10 and the actual amount of electricity remaining in the battery.

[0046] In a fourth operation, the network, for example a server in the "cloud" 100, transmits a request to the vehicle 10 to inform it of the energy saving mode(s) which have been allocated to the communication system of the vehicle 10 by the network, based on the first, second and third pieces of information.

[0047] This request or these requests are transmitted via the OTA type wireless link implemented to receive the first, second and third information and exchange data between the "cloud" 100 and the vehicle 10.

[0048] This request includes, for example, a set of communication parameters associated with the energy-saving mode(s) allocated to vehicle 10 and defining this or these energy-saving modes. Applying these parameters allows the vehicle to enter the energy-saving mode(s).

[0049] In one variant, the transmitted request(s) include an identifier for each allocated energy-saving mode. The vehicle 10 has in its memory (for example, in the memory of a computer in the vehicle 10 communication system) a lookup table (LUT) associating each identifier with an energy-saving mode and its associated parameters. According to this variant, the energy-saving modes that can be implemented by the vehicle 10 communication system are predefined and known to both the vehicle 10 and the network.

[0050] According to a specific embodiment, vehicle 10 exits the energy-saving mode(s) allocated by the network, for example automatically when one or more of the following conditions are met: Vehicle 10 moves and leaves the network cell in which it was parked; the battery of vehicle 10 recharges (for example, following the start of the internal combustion engine of vehicle 10 or following a connection of the battery of vehicle 10 to a charging station of a public or private power supply network); action by the driver to deactivate the energy saving mode(s) via an HMI for example.

[0051] [ Fig. 2 [Figure 2] schematically illustrates a communication device 2 in a public terrestrial mobile network, according to a particular and non-limiting embodiment of the present invention. The device 2 corresponds, for example, to a "cloud" server 100 or to a device onboard the vehicle 10 for communicating with the public terrestrial mobile network.

[0052] Device 2, for example, is configured to implement the operations described opposite the figure 1and / or steps of the process described in relation to the figure 3Examples of such a device 2 include, but are not limited to, a server, a computer, a computing device, embedded electronic equipment such as a vehicle's on-board computer, an electronic control unit such as an ECU, a telematics control unit (TCU), a smartphone, a tablet, and a laptop computer. The elements of device 2, individually or in combination, may be integrated into a single integrated circuit, into several integrated circuits, and / or into discrete components. Device 2 may be implemented as electronic circuits, software (or computer) modules, or a combination of electronic circuits and software modules.According to various particular embodiments, device 2 is coupled in communication with other similar devices or systems, for example via a communication bus or through dedicated input / output ports.

[0053] Device 2 includes one (or more) processor(s) 20 configured to execute instructions for carrying out the steps of the process and / or for executing instructions from the software embedded in Device 2. The processor 20 may include integrated memory, an input / output interface, and various circuits known to those skilled in the art. Device 2 further includes at least one memory 21, for example, volatile and / or non-volatile memory, and / or includes a memory storage device that may include volatile and / or non-volatile memory, such as EEPROM, ROM, PROM, RAM, DRAM, SRAM, flash, magnetic disk, or optical disk.

[0054] The computer code of the embedded software(s) including the instructions to be loaded and executed by the processor is for example stored on the first memory 21.

[0055] According to a particular and non-limiting embodiment, the device 2 comprises a block 22 of interface elements for communicating with external devices, for example, a remote server or the cloud, a vehicle communication system, a computer, or a TCU. The interface elements of block 22 comprise one or more of the following interfaces: radio frequency RF interface, for example of type Bluetooth ®< or Wi-Fi ®< , LTE (from the English "Long-Term Evolution" or in French "Evolution à long terme"), LTE-Advanced (or in French LTE-avancé), 3GPP 5G; USB interface (from the English "Universal Serial Bus" or "Bus Universel en Série" in French); HDMI interface (from the English "High Definition Multimedia Interface", or "Interface Multimedia Haute Definition" in French).

[0056] Data is for example loaded to device 2 via the interface of block 22 using a 4G (or LTE Advanced according to 3GPP release 10 - version 10) or 5G network.

[0057] According to another particular embodiment, the device 2 includes a communication interface 23 which enables communication with other devices, such as for example the GPS-type location system, the mobile communication system (GSM, GPRS, Wi-Fi, Bluetooth, LTE, LTE-V, ITS G5) or the radars of the radar system via a communication channel 230. The communication interface 23 corresponds for example to a transmitter configured to transmit and receive information and / or data via the communication channel 230.Communication interface 23 corresponds for example to a wired network of type CAN (from the English "Controller Area Network" or in French "Réseau de contrôlers"), CAN FD (from the English "Controller Area Network Flexible Data-Rate" or in French "Réseau de contrôlers à débit de données flexible"), Ethernet Automotive (or in French "Ethernet automobile"), FlexRay (according to the ISO 17458 standard) or Ethernet (according to the ISO / IEC 802.3 standard).

[0058] According to a further particular embodiment, device 2 can provide output signals to one or more external devices, such as a display screen, one or more speakers and / or other peripherals via output interfaces not shown respectively.

[0059] [ Fig. 3[Illustrates a flowchart of the different stages of a communication process between a vehicle's communication system and a public terrestrial mobile network, according to a particular and non-limiting embodiment of the present invention. The process is advantageously implemented in the network (for example, in one or more servers), for example, implemented by device 2 of the figure 2 .

[0060] In a first step 31, a first representative piece of information on the vehicle's electrical consumption is received.

[0061] In a second step 32, a second piece of information representing a quantity of electricity available in the vehicle is received.

[0062] In a third step 33, a third piece of information representing an objective of maintaining a connection between the communication system and the network for a specified period is received.

[0063] In a fourth step 34, at least one energy saving mode to be allocated to the vehicle's communication system is determined based on the first piece of information, the second piece of information, and the third piece of information.

[0064] In a fifth step 35, an instruction to switch to at least one specified energy saving mode is transmitted to the vehicle's communication system.

[0065] According to one variant, steps 31 to 35 are repeated to take into account variations in the electrical consumption of vehicle 10, its needs and changes in the amount of electricity available.

[0066] Of course, the invention is not limited to the embodiments described above but extends to a method for managing communication between a vehicle and a network, and to the device configured for implementing such a method. The invention also relates to a method for managing energy in a vehicle, and the device configured for implementing such a method.

[0067] The invention also relates to a system comprising one or more vehicles, for example automobile or more generally a land motor vehicle, communicating with one or more servers or network devices such as device 2.

Claims

1. A method for communication between a vehicle communication system (10) and a public terrestrial mobile network (100), said vehicle (10) being stationary within a cell of said network (100), said method being implemented by said network (100), said method comprising the following steps: - receiving (31) a first piece of information representing the electrical consumption of said vehicle (10); - receiving (32) a second piece of information representing the amount of electricity available in said vehicle (10); - receiving (33) a third piece of information representing the objective of maintaining a connection between said communication system and said network for a specified duration; - determining (34) at least one energy-saving mode to be allocated to said vehicle communication system (10) based on said first, second, and third pieces of information; - transmitting (35) to said vehicle communication system (10) an instruction to switch to said at least one specified energy-saving mode. characterized in that said determination of at least one energy saving mode includes a selection of an energy saving profile from a plurality of energy saving profiles, to each profile of said plurality being associated a set of applications and / or services to be kept in operation with a set of associated communication parameters, said set of communication parameters comprising: - a data exchange frequency; and / or - a data packet size .

2. Method according to claim 1, wherein said determination of at least one energy saving mode comprises a selection of a sleep mechanism for said vehicle communication system (10) at regular intervals of determined duration from among a plurality of mechanisms supported by said network (100).

3. A method according to claim 2, wherein said plurality of mechanisms comprises: - energy saving mode mechanism, called PSM; - discontinuous reception mechanism, called DRX; - extended discontinuous reception mechanism, called eDRX ; - discontinuous reception mechanism in connected mode, called CDRX.

4. A method according to any one of the preceding claims, wherein said plurality of energy saving profiles includes a profile in which only one or more emergency services are kept in operation.

5. A method according to any one of the preceding claims, wherein said selection of an energy saving profile is a function of a virtual image of said communication system of said vehicle (10) recorded in said network.

6. Device (2) included in a public terrestrial mobile network, said device (2) comprising a memory (21) associated with at least one processor (20) configured for carrying out the steps of the method according to any one of claims 1 to 5.

7. Communication system comprising the device according to claim 6 and at least one vehicle connected to said public terrestrial mobile network via a wireless link.

8. Product computer program comprising instructions adapted for carrying out the steps of the process according to any one of claims 1 to 5, when the computer program is executed by at least one processor.