Method and communication control device for data transmission in a vehicle

Abstract

The invention relates to a method for transmitting data packets provided by at least one stationary data transmission device (2) via at least one channel (10) in a vehicle (1). The data packets are received by the communication control device (100) by means of a communication module (120) adapted for reception via the at least one channel (10) and cached in a memory (140), an allowable transmission delay being determined for each data packet, and transmitting the data packets to at least one further component (200, 300) of the vehicle (1) in an ascending order of permissible transmission delays via at least one data transmission path (201, 202), the transmission rate of which is lower than the maximum transmission rate of the at least one channel (10). The invention further relates to a communication control device (100) for carrying out such a method, and to an arrangement of components in a vehicle (1) having at least one such communication control device (100).

Description

Technical Field

[0001] The invention relates to a method for transmitting data packets in a vehicle according to the preamble of claim 1. The invention also relates to a communication control device for a vehicle according to the preamble of claim 4. Furthermore, the invention relates to an arrangement of components in a vehicle according to the preamble of claim 6. Background Art

[0002] Fixed-site data transmission devices, for example those installed along traffic routes, are known to be used for various channels, for example for transmitting data via ultrashort waves (USW), microwaves or infrared light. With the aid of these data transmission devices, data packets can be sent to moving vehicles and / or received from these vehicles. Such data packets can, for example, include information about traffic flow, traffic disturbances, restrictions on the availability of traffic routes according to vehicle weight, vehicle type, vehicle height or similar parameters, or the resulting road use charges (tolls).

[0003] Furthermore, for example, from the published patent document DE 10 2018 221 933 A1, a distributed data exchange system for vehicles is known, which has a local static intermediate memory for buffering data. The distributed data exchange system also has a sending device in a first vehicle for sending the data to be buffered to the local static intermediate memory via a first short-distance interface; a receiving device in a second vehicle passing through the intermediate memory for receiving the buffered data from the local static intermediate memory via a second short-distance interface; and a processor connected to the intermediate memory. The processor is adapted to process the data sent to the intermediate memory, generate environmental model data, write the environmental model data to the intermediate memory, and send it to the second vehicle.

[0004] Publication WO 2021 / 043841 A1 describes a device for controlling access to a wireless communication network using a time multiplexing method. The device includes a time slice allocation module, which is adapted to allocate time slices to data transmission from a first node to a second node, and a verification module, which is adapted to verify the data packet based on the delay requirement of the data packet and the delay of the data packet expected at the time point of the allocated time slice before transmitting the data packet from the first node to the second node. The verification module is used to distinguish between data packets to be transmitted and data packets not to be transmitted. The device also includes a time control module, which is adapted to allocate the data packets to be transmitted in time to the time slice for transmission from the first node to the second node.

[0005] Data received from mobile vehicles via data transmission devices and / or from fixed-position intermediate storage devices have very different requirements with regard to the maximum permissible delay (i.e. the delay until processing and / or display in the respective vehicle). Some information, such as general information about road conditions or traffic jams a little further away, is less time-critical or non-urgent. Other information, such as warning messages about catastrophic events such as tsunamis or earthquakes and payment notices related to road user charges (tolls), must be processed and / or displayed immediately or within a very short deadline.

[0006] Such data packets are usually small in size, usually between 10 kilobytes and 100 kilobytes. However, the channel used for data transmission between the fixed data transmission device and the vehicle must have a transmission rate that ensures that all valid data as well as all metadata and security data required for the transmission protocol are fully received within a time window, which may be strictly limited by the maximum movement speed of the vehicle and the minimum range of the data transmission device.

[0007] The transmission rates required for such channels thus created often significantly exceed the bandwidth or transmission rates typically used for data transmission between components within a vehicle, sometimes by one or more orders of magnitude.

[0008] Therefore, it is necessary to equip the communication control device designed to receive data via such a channel with special data transmission interfaces (hereinafter also referred to as gateways), which enable higher data transmission rates than are usually provided in vehicles. Such special gateways lead to higher manufacturing costs on the one hand, in particular because they need to be provided not only to the communication control device, but also to other components for processing and / or displaying data received via such a channel.

[0009] Furthermore, data transmission paths with higher bandwidth are more sensitive to interference, especially electromagnetic interference, and therefore place higher demands on cabling and installation.

[0010] Therefore, a method is needed with which data packets received via a channel with a high transmission rate can be distributed within the vehicle via data transmission paths having a significantly lower transmission rate than the channel, without thereby affecting the requirements for a maximum tolerable delay for the transmission of such data packets. Summary of the invention

[0011] The object of the present invention is to provide an improved method for transmitting data packets in a vehicle. This object is achieved by a method having the features of claim 1 .

[0012] Another object of the present invention is to provide an improved communication control device for a vehicle. The present invention achieves the above object by a communication control device having the features of claim 4.

[0013] It is also an object of the invention to provide an improved arrangement of components in a vehicle. This object is achieved by an arrangement having the features of claim 6 .

[0014] Advantageous embodiments of the invention are the subject matter of the dependent claims.

[0015] According to a first aspect of the invention, in a method for transmitting data packets in a vehicle provided by at least one stationary data transmission device via at least one channel, the data packets are received by a communication control device of the vehicle by means of a communication module and buffered in a memory, the communication module being adapted for receiving via the at least one channel. In one embodiment, a time stamp is set for the data packet when buffering the data packet, the time stamp indicating the time of reception by the communication module.

[0016] For each data packet, a permissible transmission delay is determined, which indicates the time frame within which, after receipt of the data packet by the communication module, the data packet should be processed and / or presented, for example displayed, in the vehicle.

[0017] For example, a data packet indicating a traffic jam that is still far from the vehicle is assigned a relatively large transmission delay. Conversely, a data packet indicating a toll to be paid when driving on a toll road is assigned a relatively low transmission delay. Similarly, a data packet indicating a warning message such as a tsunami, earthquake, or embankment fire along the road ahead is assigned a relatively low transmission delay.

[0018] The data packets are transmitted in sequence to at least one other component of the vehicle via at least one data transmission path, wherein the data transmission path is adapted for exchanging data with a communication control device and has a transmission rate that is less than the maximum transmission rate of the at least one channel for receiving data from the at least one fixed-position data transmission device.

[0019] The transmission order of the data packets is determined such that the permissible transmission delay of each data packet is observed.

[0020] For example, the latest possible permissible transmission time of the data packet can be determined from the timestamp of the data packet received by the communication module with the aid of the transmission delay, i.e., the time before which the data packet must be transmitted to the at least one further component via the data transmission path. Thus, all cached data packets can be sorted according to their latest possible permissible transmission time, starting with the earliest (i.e., most recent) permissible transmission time, and transmitted in the order of this list. In this way, the correct transmission of all data packets in time can be ensured if the transmission rate of the data transmission path is sufficient.

[0021] In other words: Data packets received by the communication control device are buffered and given priority when forwarded via the data transmission path in such a way that data packets to be transmitted urgently receive a high priority, while data packets to be transmitted less urgently receive a low priority.

[0022] In this way, data received from the channel within a transmission time window limited by the minimum range of the stationary data transmission device and the maximum speed of the vehicle can be distributed to other components in the vehicle over a relatively long period of time without data packets being lost or requirements with regard to transmission delay being violated.

[0023] It is therefore possible to use a cost-effective gateway with a lower transmission rate for the at least one data transmission path in the vehicle than is possible in the prior art. In particular, a gateway that is especially specialized and designed for particularly high transmission rates, such as a Universal Serial Bus (USB) interface or a Controller Area Network Flexible Data Rate (CAN-FD) gateway, can be omitted.

[0024] Furthermore, a higher level of interference safety of the at least one data transmission path is achieved. Furthermore, the requirements for the wiring and installation of such a data transmission path in a vehicle can be relaxed.

[0025] In one embodiment of the method, the data transmitted by the communication control device via the at least one data transmission path at least partially includes toll payment information, and the transmission rate of the at least one data transmission path is less than the maximum transmission rate of the at least one channel.

[0026] By allocating a low transmission delay to data packets containing such toll payment information and correspondingly giving them a high priority in transmission to the at least one further component in the vehicle, these data packets are presented and / or processed with priority, thereby ensuring that the payment process of the toll is carried out properly despite the relatively limited transmission rate of the communication control device (compared to the channel).

[0027] In another embodiment of the method, the data transmitted by the communication control device via the at least one data transmission path at least partially comprises an emergency warning message, the transmission rate of the at least one data transmission path being less than the maximum transmission rate of the at least one channel.

[0028] Since data packets comprising such urgent warning messages are assigned a low transmission delay and are accordingly given a high priority in their transmission to the at least one further component in the vehicle, these warning messages are presented and / or processed with priority. Thus, despite the relatively limited transmission rate of the communication control device (compared to the channel), it is ensured that the vehicle occupants are correctly and reliably informed of the imminent warning messages.

[0029] According to a second aspect of the present invention, a communication control device for a vehicle includes a communication module, the communication module having a transceiver device, the transceiver device being configured to receive data packets from a fixed-position data transmission device via at least one channel. According to the present invention, the communication control device also includes a memory for caching data packets, a computing unit, and at least one gateway, each gateway being adapted to be connected to a data transmission path, respectively, the transmission rate of the data transmission path being less than the maximum transmission rate of the at least one channel, wherein the communication control device is adapted to execute the method for transmitting data packets in a vehicle as described in the first aspect of the present invention. In particular, the communication control device is adapted for priority division, and the memory is adapted to cache data packets received via the channel.

[0030] By selecting the transmission rate of the at least one gateway to be lower than the transmission rate of the channel, such a communication control device according to the invention can be constructed using simpler components that are also less susceptible to interference, in particular gateways that are widely used and cost-effective in automobile construction. Further advantages of the communication control device according to the invention correspond to the advantages of the method according to the invention for transmitting data packets in a vehicle.

[0031] In one embodiment, the at least one gateway is designed as a controller area network (CAN) gateway, whose transmission rate is less than the maximum transmission rate of the at least one channel. Such CAN gateways are particularly widely used in automobile manufacturing and are inexpensive.

[0032] According to a third aspect of the present invention, a component arrangement structure, which can be designed, for example, as a control device, an infotainment component or a display and operating device, comprises at least one component, which is designed as a communication control device according to the second aspect of the present invention and is adapted to receive data packets from a fixed-position data transmission device via at least one channel and to be connected to at least one other component via a data transmission path, the transmission rate of which is less than the maximum transmission rate of the at least one channel.

[0033] The advantages of this arrangement correspond to the advantages of the method for transmitting a data packet in a vehicle in the first aspect of the invention, and the advantages of the communication control device in the second aspect of the invention.

[0034] In one embodiment, at least one further component connected to the communication control device is designed as an infotainment head unit and is adapted to determine a driving route of the vehicle.

[0035] The invention is based on the recognition that such an infotainment head unit in its typical operating mode receives urgent data packets with a short transmission delay, such as warning messages about natural disasters or toll payment information, only in very rare cases, while receiving data packets with a high transmission delay, which are less time-critical or not urgent, relatively more frequently, but still at sufficiently long time intervals.

[0036] By means of the method according to the invention, data packets are given priority according to their maximum permissible transmission delay and the data packets are buffered in a memory until they are transmitted via the at least one data transmission path, thereby enabling bursty data transmission on a channel at a high data transmission rate to be smoothed. It is therefore possible to perform data transmission at a significantly lower data transmission rate without affecting the safety or reliability of the infotainment head unit. Other advantages of this embodiment correspond to the advantages of the method for transmitting data packets in a vehicle in the first aspect of the invention and the advantages of the communication control device in the second aspect of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Embodiments of the present invention are explained in more detail below with reference to the accompanying drawings.

[0038] In the attached picture:

[0039] Figure 1 A stationary data transmission device and a vehicle with a communication control device are shown schematically.

[0040] In all the figures, parts which correspond to one another are provided with the same reference numerals. DETAILED DESCRIPTION

[0041] Figure 1 The diagram schematically shows a moving vehicle 1 and a fixed data transmission device 2. The vehicle 1 includes a communication control device 100, an infotainment main unit 200, and other electrical and / or electronic components. Figure 1 The information is schematically summarized in the vehicle electronic device 300. The infotainment main unit 200 (hereinafter referred to as the main unit 200) is connected to the communication control device 100 and the vehicle electronic device 300 using corresponding bidirectional data transmission paths 201, 202 to exchange data and / or control commands.

[0042] The vehicle 1 and the data transmission device 2 are adapted to exchange data via a channel 10 .

[0043] The channel 10 can be designed, for example, as a unidirectional frequency modulation channel 10, via which data packets are sent by the data transmission device 2, which is preferably designed as a ground transmission station, so that these data packets are provided in a broadcast manner for reception by a plurality of vehicles 1. Via such a frequency modulation channel 10, data packets of a maximum of 50 kilobytes can be transmitted at a data transmission rate of approximately 16 kilobits per second at a typical carrier frequency of between 76 MHz and 90 MHz within a typical radius of approximately 10 km to 50 km.

[0044] In another embodiment, the channel 10 can also be designed as a microwave channel 10, in which a maximum of 25 kilobytes of data packets are transmitted via a carrier frequency of typically 5.8 GHz at a data transmission rate of approximately 4 megabits per second. In this embodiment, the data transmission station 2 is designed as a fixed-position microwave beacon with a typical range of up to 20 meters, usually installed along traffic routes with heavy traffic, such as highways and expressways.

[0045] In another embodiment, the channel 10 can also be designed as an infrared channel 10, in which data packets of up to 10 kilobytes are transmitted via an optical connection between the vehicle 1 and a data transmission station 2 designed as an infrared beacon. Such infrared beacons usually have a range of up to 3.5 meters, are adapted for a data transmission rate of up to 1 megabit per second from the infrared beacon to the vehicle 1 (downlink) and a data transmission rate of up to 64 kilobit per second from the vehicle 1 to the infrared beacon (uplink), and are installed along traffic routes with normal or low traffic volume.

[0046] To simplify the representation, Figure 1 Only one channel 10 is shown in FIG. 1 , but the vehicle 1 is usually adapted for exchanging data with various stationary data transmission devices 2 , which data exchange can take place via several channels 10 of different designs.

[0047] The infotainment head unit or head unit 200 arranged on the vehicle side processes the data transmitted via the channel 10 and / or provides such data for transmission.

[0048] For example, the main unit 200 is adapted to be used primarily for route planning, i.e. for calculating a driving route of the vehicle 1 based on the position data and the map data. For such route planning, traffic data provided via at least one channel 10 may be taken into account. The traffic data may include information about traffic flow and / or traffic guidance, such as information about current road closures, congestion or other restrictions along the route, which is relevant for route planning. The presentation and processing of the traffic data by the main unit 200 is usually not time-critical.

[0049] In addition, the head unit 200 can display important information to the vehicle occupants, such as warnings of severe weather or disaster conditions along the driving route, which is also provided by the fixed-location data transmission device 2 via one or more channels 10.

[0050] In addition, the main unit 200 can present and / or process important information related to the specific traffic route on which the vehicle 1 is currently traveling, such as information about tolls payable (i.e., information about amounts that need to be paid immediately when using a certain road section), information about height restrictions or tonnage restrictions, such as when passing through ferries, tunnels, bridges or other transportation facilities.

[0051] Such information, which is listed here only by way of example and by no means exhaustively, can also be provided via the stationary data transmission device 2. Such information can require an immediate reaction from the head unit 200 or other components of the vehicle electronics 300 and / or the vehicle occupants of the vehicle 1.

[0052] The invention is therefore based on the recognition that different data received by the vehicle 1 via one or more channels 10 need to be processed with different time urgency or priority. Some of these data are associated with strict real-time requirements and must be processed and / or presented to the vehicle occupants within a predetermined time frame or within a permissible transmission delay (from the time of receipt by the vehicle 1). Other data are associated with loose real-time requirements, i.e. these data must be processed and / or presented within a certain time frame in a statistical average sense, but in sufficiently rare individual cases, this time frame may also be exceeded. Other data have no special time requirements for processing and / or presentation.

[0053] Based on this knowledge, the object of the present invention is to organize the transmission, storage and processing of such data received via one or more channels 10 in vehicle 1 in such a way that all time requirements are met with particularly low technical effort and without data losses.

[0054] To this end, a communication module 120 is provided in the communication control device 100 for data exchange via the at least one channel 10, and the communication module has at least one transceiver device 121. Thus, for example, the first transceiver device 121 can be adapted to be an ultra-short wave receiver for receiving data via the frequency modulation channel 10, the second transceiver device 121 can be adapted to be a microwave receiver for receiving data via the microwave channel 10, and the third transceiver device 121 can be adapted to be a bidirectional infrared transceiver for receiving and sending data via the infrared channel 10.

[0055] The communication control device 100 further includes a computing unit 130 and a memory 140. The computing unit 130 is connected to the communication module 120 and the memory 140 in such a way that data can be transmitted between the computing unit 130 and the communication module 120 and data can be stored in and / or read from the memory 140.

[0056] In the embodiment shown in this case, the memory 140 is designed as a separate element from the computing unit 130, such as an independent storage module. Therefore, it is easy to manufacture communication control devices 100 with different configurations, which are adapted to different requirements by adopting memories 140 of different designs, such as memories with different storage capacities and / or transmission rates.

[0057] Alternatively, the memory 140 can however also be designed as a subelement of the computing unit 130. Thus, for example, higher data read and write transfer rates can be achieved on the memory 140.

[0058] The data received by the communication module 120 via the channel 10 are transmitted to the computing unit 130. According to the invention, the computing unit 130, preferably by means of a computing program implemented thereon, is adapted to determine the maximum permissible transmission delay of such received data (and therefore also the priority of transmission to further components 200, 300 in the vehicle 1). In other words: the computing unit 130 sorts these data into a sequence, transmits them to the main unit 200 in this sequence, and satisfies the time requirements for the presentation and / or processing of all these data.

[0059] The data that does not need to be directly ("directly" means the highest priority) transmitted to the main unit 200 are cached in the memory 140, and only read and transmitted from there after the data with higher priority have completed the transmission. After the data transmission, they can be deleted from the memory 140 again to make room for the subsequent data to be cached.

[0060] In this way, all time requirements relating to the data of the channel 10 can be complied with even if the data transmission path 201 between the communication control device 100 and the main unit 200 has only a low transmission rate. In particular, this data transmission path 201 can have a transmission rate that is significantly lower than the transmission rate required to transmit all data received from the channel 10 via the communication module 120 in the order in which they were received (i.e. without being sorted and buffered according to their time priority).

[0061] In other words, the performance requirements for the data transmission path 201 can be relaxed in the following way: the data transmitted from the data transmission device 2 is buffered in the memory 140 of the communication control device 100 and transmitted to the main unit 200 according to its delay requirements according to priority, and although these data are transmitted at a high transmission rate in a burst manner, the data packet size is small and is sufficient relative to the burst duration or effective occupancy time of the channel 10.

[0062] In one embodiment, a data transmission path 201 between the main unit 200 and the communication control device 100 is formed by interconnected, simple and low-cost controller area network (CAN) gateways 210, 110. Therefore, it is advantageously no longer necessary to use a gateway with a higher transmission rate, such as a CAN flexible data rate (CAN-FD) gateway. Similarly, it is no longer necessary to provide other interfaces, such as a universal serial bus (USB) interface, between the communication control device 100 and the main unit 200 in addition or alternatively. Therefore, both the communication control device 100 and the main unit 200 can adopt a simpler and more cost-effective design. The design and installation of the cable or cable group used to connect the communication control device 100 and the main unit 200 can also be simplified. In addition, the risk of failure of the data transmission path 201 is also reduced by this simplified design.

[0063] In a similar manner, the performance requirements of the components which transmit the data initially received by the channel 10 and transmitted to the main unit 200 further to the vehicle electronics 300 can be relaxed. Thus, the data transmission path 202 between the vehicle electronics 300 and the main unit 200 can also be formed by a cost-effective, simple CAN gateway 310, 220. A more complex, more expensive and more prone to failure CAN-FD gateway or USB interface can also be omitted here.

Claims

1. A method for transmitting data packets in a vehicle (1), wherein the data packets are provided by at least one stationary data transmission device (2) via at least one channel (10), It is characterized in that The data packet is received by the communication control device (100) by means of a communication module (120) and buffered in a memory (140), wherein the communication module (120) is adapted to receive via the at least one channel (10), wherein a permissible transmission delay is determined for each data packet and the data packets are transmitted in sequence to at least one further component (200, 300) of the vehicle (1) via at least one data transmission path (201, 202), the transmission rate of the at least one data transmission path being lower than the maximum transmission rate of the at least one channel (10), The transmission order of the data packets is determined so as to comply with the allowable transmission delay of each data packet.

2. The method according to claim 1, It is characterized in that The data transmitted via the at least one transmission path (201, 202) at least partially includes toll payment information.

3. The method according to any one of the preceding claims, It is characterized in that The data transmitted via the at least one transmission path (201, 202) at least partially comprises at least one emergency warning message.

4. A communication control device (100) for a vehicle (1), comprising a communication module (120), the communication module having a transceiver device (121), the transceiver device being adapted to receive data packets from a fixed-position data transmission device (2) via at least one channel (10), It is characterized in that The communication control device (100) comprises a memory (140) for caching data packets, a computing unit (130) and at least one gateway (110), each gateway being used to connect to a data transmission path (201), the transmission rate of the data transmission path being less than the maximum transmission rate of the at least one channel (10), and wherein the communication control device (100) is adapted to execute the method according to any one of claims 1 to 3.

5. The communication control device (100) according to claim 4, It is characterized in that The at least one gateway (110) is designed as a controller area network (CAN) gateway, whose transmission rate is lower than the maximum transmission rate of the at least one channel (10).

6. An arrangement of components (100, 200, 300) in a vehicle (1), It is characterized in that At least one component (100, 200, 300) is designed as a communication control device (100) according to claim 4 or 5, which is used to receive data packets from a fixed-position data transmission device (2) via at least one channel (10) and is connected to at least one other component (200, 300) via a data transmission path (201, 202), the transmission rate of which is less than the maximum transmission rate of the at least one channel (10).

7. The arrangement according to claim 6, It is characterized in that At least one component (100, 200, 300) is designed as an infotainment head unit (200) and is adapted to determine a driving route of the vehicle (1).

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