Method and apparatus for data communication in a vehicle between an actuation apparatus and multiple units

Abstract

In the case of the method and the apparatus for data communication in a vehicle between an actuation apparatus and multiple units, which may be sensors and / or actuators, there are multiple communication channels (22 to 28), by way of each of which at least one unit (14 to 20) is communicatively connected to the actuation apparatus (12). The communication between the actuation apparatus (12) and the units (14 to 20) is performed by transmitting signal pulse sequences (22' to 28') of pulses (30) with the same repetition rate, which have rising edges (32). Signal pulse sequences (22' to 28') transmitted via at least two of the communication channels (22 to 28) are transmitted with a phase shift in relation to one another, and so the rising edges (32) of the pulses (30) of one transmitted signal pulse sequence (22' to 28') have a time offset with respect to the rising edges (32) of the pulses (30) of the or each other transmitted signal pulse sequence (22' to 28') within the period defined by the repetition rate.

Description

[0001] Method and device for data communication in a vehicle between a control device and several units

[0002] The invention relates to a method and a device for data communication in a vehicle between a control device and a plurality of units, which may primarily be sensors and / or actuators. In other words, the invention relates to a method and a device for bidirectional data exchange via at least two communication buses (such as DSI3), to each of which a control device (master) and one or more functional units (slaves) are connected.

[0003] The various units of a vehicle subsystem, such as an ultrasonic (US) measurement system for parking sensors, are typically connected to the control unit via a communication bus. However, in modern US systems, for reasons of faster (due to parallelized) data transmission, each US transducer is connected to the control unit via a separate communication line.

[0004] For data communication, signals are modulated, typically in the form of signal pulse sequences. Signal modulation inevitably results in EMC emissions. If multiple communication buses or communication lines are connected in parallel and, as is common practice, combined at least in cable harnesses, the impact of EMC emissions increases. This can be counteracted by EMC-reducing measures, but if the EMC load is too high, this is only possible to a limited extent or requires considerable effort.

[0005] The object of the invention is to provide a method and a device for data communication in a vehicle in which the addition of EMC emissions is reduced despite the use of several communication channels.

[0006] To achieve this object, the invention proposes a method for data communication in a vehicle between a control device and a plurality of units, which may be sensors and / or actuators, wherein the method comprises a plurality of communication channels, via which at least one unit is in communication connection with the control device,the communication between the control device and the units is effected by transmitting signal pulse sequences consisting of pulses having rising edges and having the same repetition frequency, and the signal pulse sequences transmitted by the control device via at least two of the communication channels to the units communicating with them are phase-shifted relative to one another, so that the rising edges of the pulses of one transmitted signal pulse sequence are, within the period defined by the repetition frequency, time-shifted relative to the rising edges of the pulses of the or any other transmitted signal pulse sequence, and / or this also applies to the falling edges of the pulses relative to one another, and / or the steepness of the rising edges of the pulses of one signal pulse sequence is selected to be different from the steepness of the rising edges of the pulses of the or any other signal pulse sequence.

[0007] The idea pursued by the invention is to use signal pulse sequences for communication between the control device and the units. These pulses are provided with rising edges and have the same repetition frequency. The control device transmits these signal pulse sequences via the individual communication channels with a phase shift, thus preventing the rising edges of the pulses of two signal pulse sequences from coinciding in time, which preferably also applies to the falling edges. This reduces the strength of EMC radiation.

[0008] Typically, after a phase-shifted signal pulse sequence of the type according to the invention is output by the control device, the units in turn send their own signal pulse sequences as responses back to the control device. What was previously stated in connection with the signal pulse sequence of the control device also applies to these response signal pulse sequences. The units can, for example, have ultrasonic transducers that can be used for monitoring the surroundings of a vehicle. The invention concerns the communication between the control device and the units, not the emitted ultrasonic signals and their echo signals due to reflection from objects in the vehicle's surroundings.

[0009] The communication channels can be data communication buses known in the state of the art, such as DSI3 or similar. In particular, the data communication buses are bidirectional.

[0010] According to the invention, the said modification reduces the radiation characteristics of the communication system, whereby a superposition of the radiation energies is prevented by the phase shift with which the individual signal pulse sequences are transmitted.

[0011] As an alternative to the phase shift or in addition to it, it can be provided to select the steepness of the rising edges of the pulses of the signal pulse sequences differently.

[0012] In an advantageous development of the invention, it can be provided that the signal pulse sequences transmitted via all communication channels are phase-shifted with respect to one another and thus the rising edges of the pulses of one of the transmitted signal pulse sequences are time-shifted within one period of the repetition frequency with respect to the rising edges of the pulses of any other transmitted signal pulse sequence and / or the steepness of the rising edges of the pulses of one of the signal pulse sequences is selected to be different from the steepness of the rising edges of the pulses of any other signal pulse sequence.

[0013] In a further advantageous development of the invention, it can be provided that only one unit is in communication connection with the control device via at least some of the communication channels or via each communication channel. In an expedient embodiment of the invention, it can be provided that at least some of the communication channels or each communication channel is designed as a bus to which several units are connected.

[0014] In a further expedient embodiment of the invention, it can be provided that an electrical line, in particular a cable, is selected as the communication channel.

[0015] In an advantageous development of the invention, it can be provided that the electrical lines are combined at least in sections.

[0016] The above-mentioned object is also achieved according to the invention by a device for data communication in a vehicle between a control device and a plurality of units, which may be sensors and / or actuators, with a control unit, a plurality of communication channels and a plurality of units, which may be sensors and / or actuators, wherein at least one unit is in communication connection with the control device via each communication channel,wherein the control device transmits signal pulse sequences comprising rising-edge pulses of the same repetition frequency to the units for data communication, and wherein the signal pulse sequences transmitted by the control device via at least two of the communication channels to the units communicating with them are phase-shifted relative to one another, so that the rising edges of the pulses of one transmitted signal pulse sequence are time-shifted relative to the rising edges of the pulses of the or any other transmitted signal pulse sequence within the period defined by the repetition frequency, and / or this also applies to the falling edges of the pulses relative to one another, and / or the steepness of the rising edges of the pulses of one signal pulse sequence is selected to be different from the steepness of the rising edges of the pulses of the or any other signal pulse sequence.

[0017] In an advantageous development of the invention, it can be provided that the signal pulse sequences transmitted via all communication channels are phase-shifted with respect to one another and thus the rising edges of the pulses of one of the transmitted signal pulse sequences are offset in time from the rising edges of the pulses of any other transmitted signal pulse sequence within one period of the repetition frequency and / or the steepness of the rising edges of the pulses of one of the signal pulse sequences is selected to be different from the steepness of the rising edges of the pulses of any other signal pulse sequence.

[0018] In an expedient embodiment of the invention, it can be provided that only one unit is in communication connection with the control device via at least some of the communication channels or via each communication channel.

[0019] In a further advantageous development of the invention, it can be provided that at least some of the communication channels or each communication channel is designed as a bus to which several units are connected.

[0020] In a further expedient embodiment of the invention, it can be provided that each communication channel is designed as an electrical line, in particular as a cable, and that the electrical lines are combined at least in sections.

[0021] The invention is explained in more detail below using an exemplary embodiment and with reference to the drawing. In detail:

[0022] Fig. 1 shows an embodiment of a data communication system with four separate communication channels between a control device and four individual units that are controlled separately by the control device, and Fig. 2 shows an example of four signal pulse sequences with which the control device controls the four units.

[0023] Fig. 1 shows a highly schematic representation of a data communication system 10 that can be controlled via a separate communication channel 22, 24, 26, and 28 by a control device 12 and, in this exemplary embodiment, four units 14, 16, 18, 20, designed, for example, as sensors or actuators, and that also sends signals back to the control unit 12 via this communication channel. An example of the design of the units 14 to 20 is ultrasonic transducers, which can be installed, for example, in the front or rear bumper of a vehicle.

[0024] The phase-shifted control or data communication of the control device 12 with the four units 14 to 20 by means of signal pulse sequences consisting of pulses with rising edges and the same repetition frequency is shown in Fig. 2. The reference numerals 22', 24', 26', 28' in Fig. 2 denote the signal sequences sent from the control unit 12 to the units 22, 24, 26, 28. In this exemplary embodiment, the signal pulse sequences are different, but can also have identical pulse sequences. It can be seen that at no time are pulses 30 with temporally coincident rising edges 32 sent via the four communication channels 22 to 28 (see the time offsets Ati, Atz, and Ats of the signal pulse sequences 24', 26', and 28' compared to the respective signal pulse sequence 22').The respective return signals of the units 14 to 20 controlled in this way are then also time-shifted accordingly, so that at no point in time do the rising edges on the four communication channels occur at the same time.

[0025] Additionally or alternatively, it is possible to select different slopes for the rising edges of the individual signal pulse sequences. This approach, like the phase-shifted control described above, also ensures that the radiated energies do not accumulate, which has the advantage of reducing the need for EMC protection measures.

[0026] Data communication system

[0027] Control device

[0028] Unit

[0029] Unit

[0030] Unit

[0031] Unit

[0032] Communication channel

[0033] Communication channel

[0034] Communication channel

[0035] Communication channel ' Signal pulse sequence ' Signal pulse sequence ' Signal pulse sequence ' Signal pulse sequence

[0036] pulse

[0037] rising edge

Claims

CLAIMS Method for data communication in a vehicle between a control device and several units, which may be sensors and / or actuators, wherein the method has several communication channels (22 to 28) via which at least one unit (14 to 20) is in communication connection with the control device (12),Communication between the control device (12) and the units (14 to 20) is effected by sending signal pulse sequences (22' to 28') consisting of pulses (30) having rising edges (32) of the same repetition frequency, and the signal pulse sequences (22' to 28') sent by the control device (12) to the units (14 to 20) connected to it via at least two of the communication channels (22 to 28) are phase-shifted relative to each other, so that the rising edges (32) of the pulses (30) of one transmitted signal pulse sequence (22' to 28') are time-shifted within the period defined by the repetition frequency compared to the rising edges (32) of the pulses of the (30) or any other transmitted signal pulse sequence (22' to 28'). Method according to claim 1, characterized in thatthat the signal pulse sequences (22' to 28') sent by the control device (12) to the units (14 to 20) via all communication channels (22 to 28) are phase-shifted relative to each other, and thus the rising edges (32) of the pulses (30) of one of the sent signal pulse sequences (22' to 28') are time-shifted within one period of the repetition frequency to the rising edges (32) of the pulses (30) of each other sent signal pulse sequence (22' to 28'). Method according to claim 1 or 2, characterized in that only one unit (14 to 20) is in communication connection with the control device (12) via at least some of the communication channels (22 to 28) or via each communication channel (22 to 28). A method according to claim 1 or 2, characterized in that at least some of the communication channels (22 to 28) or each communication channel (22 to 28) is configured as a bus to which several units (14 to 20) are connected. A method according to any one of claims 1 to 5, characterized in that an electrical line, in particular a cable, is selected as the communication channel (22 to 28). A method according to claim 5, characterized in that the electrical lines are grouped together at least section by section. A device for data communication in a vehicle between a control device and several units, which may be sensors and / or actuators, comprising a control unit (12), several communication channels (22 to 28), and several units (14 to 20), which may be sensors and / or actuators.wherein at least one unit (14 to 20) is in communication connection with the control device (12) via each communication channel (22 to 28), wherein the control device (12) sends signal pulse sequences (22' to 28') consisting of rising edges (32) of the same repetition frequency to the units (14 to 20) for data communication, and wherein the signal pulse sequences (22' to 28') sent by the control device (12) via at least two of the communication channels (22 to 28) to the units (14 to 20) in communication with these are phase-shifted relative to each other, and thus the rising edges (32) of the pulses (30) of one sent signal pulse sequence (22' to 28') are time-shifted within the period defined by the repetition frequency relative to the rising edges (32) of the pulses, (30) of or any other transmitted signal pulse sequence (22' to 28'). Device according to claim 7, characterized in that the signal pulse sequences (22' to 28') transmitted by the control device (12) via all communication channels (22 to 28) to the units (14 to 20) are phase-shifted relative to each other, and thus the rising edges (32) of the pulses (30) of one of the transmitted signal pulse sequences (22' to 28') are time-shifted within one period of the repetition frequency to the rising edges (32) of the pulses (30) of each other transmitted signal pulse sequence (22' to 28'). Device according to claim 7 or 8, characterized in that only one unit (14 to 20) is in communication connection with the control device (12) via at least some of the communication channels (22 to 28) or via each communication channel (22 to 28).Device according to claim 7 or 8, characterized in that at least some of the communication channels (22 to 28) or each communication channel (22 to 28) is configured as a bus to which several units (14 to 20) are connected. Device according to any one of claims 7 to 10, characterized in that each communication channel (22 to 28) is configured as an electrical line, in particular as a cable. Device according to claim 11, characterized in that the electrical lines are grouped together at least section by section.

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