FR3132958A1 - Method and device for communicating data by selecting at least one radar from a plurality of radars of a vehicle - Google Patents

Abstract

The present invention relates to a method and a communication method device implemented by a first vehicle carrying a millimeter wave radar system comprising one or more radars (101 to 104). For this purpose, at least one event associated with movement of the first vehicle in a road environment (1) is detected. One or more radars of the radar system of the first vehicle (10) are selected based on the traffic event(s) detected. The first vehicle (10) then initiates the transmission of data to one or more second vehicles (11, 12, 13) via the radar(s) selected according to a vehicle-to-vehicle type communication mode, called V2V. Figure for abstract: Figure 1

Description

Method and device for communicating data by selecting at least one radar from a plurality of radars of a vehicle

The present invention relates to communication methods and devices for vehicles, particularly automobiles. The present invention also relates to a method and a communication device using one or more radars fitted to a vehicle, in particular in the context of V2X type communication(s).

Technology background

Contemporary vehicles carry more and more means of communication which often require specific components (antennas, transmitters, receivers), complicating the electronic architecture of the vehicle and increasing its manufacturing cost.

For example, new technologies are emerging that allow the exchange of information between vehicles and/or between vehicles and the infrastructure that surrounds them, these communication technologies being grouped under the name V2X (from the English “Vehicle to Everything” or in French “Véhicule vers tout”). Thus, new information and communication technologies applied to the field of transport have appeared, such as ITS G5 (from the English “Intelligent Transportation System G5” or in French “Système de transport intelligent G5”) in Europe or DSRC (from the English “Dedicated Short Range Communications” or in French “Communications dedicated to short range”) in the United States of America which are both based on the IEEE 802.11p standard or even technology based on cellular networks called C-V2X (from the English “Cellular – Vehicle to Everything” or in French “Cellulaire – Véhicule vers tout”) which is based on 4G based on LTE (from the English “Long Term Evolution” or in French “Long-term evolution”) or 5G.

V2X communication technologies also use the 5.9 GHz frequency band, which results in a maximum rate of 6 Mbits/s for data communication. Such a maximum throughput may prove insufficient to meet the communications needs of vehicles, particularly in the context of autonomous vehicles.

Summary of the present invention

An object of the present invention is to solve at least one of the problems of the technological background described above.

Another object of the present invention is for example to reduce the diversity of certain components implemented by the means of communication of a vehicle.

Another object of the present invention is, for example, to improve communication between vehicles.

According to a first aspect, the present invention relates to a communication method for a first vehicle, the first vehicle carrying a millimeter wave radar system comprising at least one radar, the method comprising the following steps:

- detection of at least one event associated with movement of the first vehicle in a road environment;

- selection of at least one radar from the radar system based on at least one detected event;

- transmission of data to at least one second vehicle in the road environment via the at least one radar selected according to a vehicle-to-vehicle type communication mode, called V2V.

Using vehicle radar(s) to transmit or receive data in a V2V communication mode reduces the number of components required (antenna, transmitter, receiver) for V2X communications by using vehicle detection radars instead only dedicated components.

Since the frequency band used by radars is between 76 and 81 GHz, the maximum rate allowed for data communication is much higher than that allowed by the frequency band allocated to V2X or V2V communications.

Selecting one or more radars of the radar system to communicate with one or more other vehicles allows communications to be distributed spatially across the selected radar(s), allowing for more directional communications beams.

According to one variant, the at least one event belongs to a set of events comprising:

- detection of at least one second vehicle; And

- activation of a turn signal of the first vehicle.

According to another variant, when the event corresponds to the detection of at least one second vehicle, the method comprises a step of determining a position of the at least second vehicle relative to the first vehicle, the at least one selected radar corresponding to the radar of the radar system comprising the position in its coverage area for transmission and/or reception of V2V communication signals, each radar of the radar system having a different coverage area.

According to an additional variant, when the event corresponds to the activation of a turn signal, the method comprises a step of determining a side of the first vehicle for which the turn signal is activated, the at least one selected radar being positioned on the side of the first vehicle.

According to yet another variant, the radar system comprises 4 corner radars, each corner radar being arranged along an axis forming an angle of 45° relative to a longitudinal axis of the first vehicle, the coverage zone associated with each radar of the system of radars corresponding to an angular sector around the axis.

According to an additional variant, each radar of the radar system is configured for object detection in the road environment and for establishment of at least one communication according to the V2V communication mode.

According to a second aspect, the present invention relates to a communication device for a vehicle embedding a millimeter wave radar system comprising at least one radar, the device comprising a memory associated with a processor configured for implementing the steps of the method according to the first aspect of the present invention.

According to a third aspect, the present invention relates to a vehicle communication system comprising the device as described above according to the second aspect of the present invention and a millimeter wave object detection radar system comprising a plurality of radars arranged spatially on the vehicle and connected to the device as described above according to the second aspect of the present invention.

According to a fourth aspect, the present invention relates to a vehicle, for example of the automobile type, comprising a device as described above according to the second aspect of the present invention or a system as described above according to the third aspect of the present invention.

According to a fifth aspect, the present invention relates to a computer program which comprises instructions adapted for the execution of the steps of the method according to the first aspect of the present invention, in particular when the computer program is executed by at least one processor.

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

According to a sixth aspect, the present invention relates to a computer-readable recording medium on which is recorded a computer program comprising instructions for executing the steps of the method according to the first aspect of the present invention.

On the one hand, the recording medium can be any entity or device capable of storing the program. For example, the medium may comprise a storage means, such as a ROM memory, a CD-ROM or a ROM memory of the microelectronic circuit type, or even a magnetic recording means or a hard disk.

On the other hand, this recording medium can also be a transmissible medium such as an electrical or optical signal, such a signal being able to be conveyed via an electrical or optical cable, by conventional or terrestrial radio or by self-directed laser beam or by other ways. The computer program according to the present invention can in particular be downloaded onto an Internet type network.

Alternatively, the recording medium may be an integrated circuit in which the computer program is incorporated, the integrated circuit being adapted to execute or to be used in executing the method in question.

Brief description of the figures

Other characteristics and advantages of the present invention will emerge from the description of the particular and non-limiting examples of embodiment of the present invention below, with reference to the appended Figures 1 to 4, in which:

schematically illustrates a communication environment for vehicles, according to a particular and non-limiting embodiment of the present invention;

schematically illustrates a communication device for a first vehicle of the , according to a particular and non-limiting embodiment of the present invention;

schematically illustrates a communication system for a first vehicle of the and comprising the device of the , according to a particular and non-limiting embodiment of the present invention;

illustrates a flowchart of the different stages of a communication process for a first vehicle of the , according to a particular and non-limiting embodiment of the present invention.

Description of the implementation examples

A method and a communication device for a vehicle carrying a radar system comprising at least one radar will now be described in what follows with reference jointly to Figures 1 to 4. The same elements are identified with the same reference signs while throughout the description which follows.

According to a particular and non-limiting example of an embodiment of the present invention, a communication method implemented by a first vehicle carrying a millimeter wave radar system comprising one or more radars comprises the detection of at least one event associated with a movement of the first vehicle in a road environment. Such an event corresponds for example to the activation of one or more indicators of the first vehicle, for example to indicate a change of lane, and/or to the detection of one or more second vehicles also traveling in the road environment ( the detection being obtained from the radar system). One or more radars of the radar system of the first vehicle are selected according to the traffic event(s) detected. The first vehicle then initiates the transmission of data to one or more second vehicles in its environment using the selected radar(s). The data is advantageously transmitted using a vehicle-to-vehicle type communication mode, known as V2V (from the English “Vehicle-to-Vehicle”).

Using vehicle radar(s) to transmit or receive data in a V2V communication mode reduces the number of components required (antenna, transmitter, receiver) for V2X communications by using vehicle detection radars instead only dedicated components.

Furthermore, the frequency band used by radars being between 76 and 81 GHz, the maximum rate allowed for data communication is much higher than that allowed by the frequency band allocated to V2X or V2V communications.

Finally, the selection of one or more radars of the radar system to communicate with one or more other vehicles allows communications to be distributed spatially on the selected radar(s), which allows for more directional communication beams.

There schematically illustrates an environment 1 for communication between vehicles, according to a particular and non-limiting embodiment of the present invention.

There illustrates an environment 1 comprising one or more roads and/or lanes on which a first vehicle 10 and one or more second vehicles 11, 12, 13 circulate.

According to the particular and non-limiting example of the , the second vehicle 11 precedes for example the first vehicle 10 on the lane of the first vehicle 10. The second vehicle 1 travels on another lane adjacent to that of the first vehicle 10, this adjacent lane being to the left of the lane of circulation of the first vehicle 10 according to the direction of circulation of the first vehicle 10. The second vehicle 13 circulates on a traffic lane adjacent to that of the first vehicle 10, this adjacent lane being to the right of the traffic lane of the first vehicle 10 according to the direction of travel of the first vehicle.

The first vehicle 10 and at least part of the second vehicles 11 to 13 are advantageously configured to communicate using a so-called V2X communication mode, for example based on the 3GPP LTE-V or IEEE 802.11p standards of ITS G5. In such a V2X communication mode, each vehicle has a node to enable vehicle-to-vehicle V2V (vehicle-to-vehicle) and vehicle-to-vehicle-to-infrastructure (V2I) communication. -infrastructure") and/or vehicle-to-pedestrian V2P, the pedestrians being equipped with mobile devices (for example a smartphone) configured to communicate with vehicles.

According to the present invention, the first vehicle 10 and one or more second vehicles 11 to 13 are in particular configured to communicate or exchange data via one or more wireless links based on V2V technology.

The first vehicle 10 is advantageously equipped with a millimeter wave radar system. The system comprises one or more radars, for example 4, 6, 8, 10 radars distributed over the first vehicle 10 to detect objects in the environment around the first vehicle 10. Each radar is adapted to emit electromagnetic waves and to receive the echoes of these waves returned by one or more objects, with the aim of detecting obstacles and their distances with respect to the first vehicle 10 for example. Each radar, or at least part of the plurality of radars, is further adapted to transmit and receive electromagnetic waves to communicate with another entity, for example one or more second vehicles 11 to 16. A radar capable of both detecting objects and allowing radio communication with another entity is for example described in document WO2012/037680 A1, published on March 29, 2012. Such a radar comprises for example 2 modulators, 1 first modulator for generating waves for detecting objects and a second modulator for generating waves having suitable characteristics for carrying communication data. According to another example, each radar includes only one modulator and offers dual object detection/communication functionality by implementing a spread spectrum technique, for example direct sequence spread spectrum (or DSSS in English). , for “Direct-Sequence Spread Spectrum”), frequency hopping spread spectrum (or FHSS in English, for “Frequency-Hopping Spread Spectrum”) or even CDMA (from English “Code Division Multiple Access” or in French “Code division multiple access”). According to yet another example, the dual object detection/communication functionality is implemented by the use of the OFDM technique (from the English “Orthogonal Frequency-Division Multiplexing” or in French “Multiplexing by distribution of orthogonal frequencies").

The radars of the radar system of the first vehicle 10 are for example used as part of an automobile driving assistance system (ADAS in English, for “Advanced driver-assistance system”). Part of the radars is for example used for the detection of objects (other vehicles, obstacles, pedestrians for example) and another part of the radars for blind spot detection. The ADAS function(s) using data obtained from radars correspond for example to one or more of the following functions:

- object detection;

- vehicle detection in a blind spot;

- Parking assistance ;

- anti-collision;

- adaptive cruise control.

These ADAS functions are for example implemented by one or more dedicated computers. The data obtained from the radars on the basis of the waves generated by the radars are for example transmitted to this or these computers (via one or more data buses for example) for implementation of the ADAS functions.

The first vehicle 10 comprises for example 4 radars 101, 102, 103 and 104 adapted to detect objects and transmit (and receive) communication data, for example of V2V or V2I type, to (from) other communication equipment. The 4 radars correspond for example to corner radars (from the English “Corner radar”) arranged at each “corner” of the vehicle, for example 1 front left radar 101, 1 front right radar 102, 1 rear right radar 103 and 1 left rear radar 104. Each radar is for example arranged on the first vehicle 10 so that the main axis of emission of electromagnetic waves forms an angle of 45° with the longitudinal axis 100 of the first vehicle 10. Such a main axis transmitter 1030 is shown on the for the right rear radar 103, forming an angle α of 45° with the longitudinal axis 100. Each radar 101 to 104 emits waves in a determined angular sector, for example 90° or 120° around the main axis of transmission, which makes it possible to cover 360° in transmission/reception around the first vehicle 10.

The radars 101 to 104 of the radar system are for example implemented as part of an automobile driving assistance system (ADAS in English, for “Advanced driver-assistance system”). Radars are for example used for object detection (obstacles, pedestrians for example) and/or for blind spot detection.

Of course, the number of radars arranged on the first vehicle 10 is not limited to 4 but extends to any number, for example 6, 8, 10 or more radars. The first vehicle 10 comprises for example one or more front radars in addition to the radars 101, 102, one or more rear radars in addition to the radars 103, 104 and/or radars arranged on the exterior mirrors for blind spot detection, etc. The angle between the main transmission axis and the longitudinal axis 100 then depends on the position of the radar.

The second vehicle(s) 11 to 13 with which the first vehicle 10 communicates in V2V are also equipped with such a radar system configured to transmit and receive electromagnetic waves for data communication. On the , as an illustrative example, only the left rear radar 131 is illustrated for the second vehicle 13 and only the right rear radar 121 is illustrated for the second vehicle 12.

Each radar operates for example in the frequency band around 77 GHz, for example in the 76-81 GHz band, according to standard EN 302 264.

A communication process between the first vehicle 10 on the one hand and one or more second vehicles 11, 12, 13 on the other hand is advantageously implemented by the first vehicle 10, that is to say by one or more processors of a computer or a combination of computers of the on-board system of the first vehicle 10, for example by the computer or computers in charge of controlling the radar system and/or a telematic control unit, called TCU (from the English "Telematic Control Unit").

In a first operation, one or more events associated with the movement of the first vehicle 10 in the road environment 1 are detected.

Such an event corresponds for example to:

- the detection of one or more second vehicles 11 to 13 in the environment of the first vehicle 10; and or

- detection of the activation of one or more indicators of the first vehicle 10.

The detection of one or more second vehicles 10 is obtained from data received from one or more radars of the radar system equipping the first vehicle 10.

For example, the presence of the second vehicle 12 near the first vehicle 10 (that is to say at a distance less than a threshold from the first vehicle 10) is detected by the radar 101 of the first vehicle 10 and the presence of the second vehicle 13 is detected by radar 102.

Object detection by radar is based on the Doppler effect. For this purpose, electromagnetic waves are emitted by the radars, these waves being for example maintained with linear frequency modulation (FMCW or LMCW, from English “Frequency Modulated Continuous Wave” or “Linear Modulated Continuous Wave”), like this is classically the case for radars on board a vehicle. Such modulation makes it possible to obtain information on the distance and speed of the detected objects. Once generated at a determined frequency or frequency range, the waves are emitted for propagation in the air at a determined power and under specific radiation conditions. Once reflected by the detected object(s), the reflected waves (echo) are received by the radar for processing and analysis, in order to deduce useful information (distance of the detected object from the radar, speed of the detected object, azimuth of the detected object corresponding to the angle of incidence of the wave in a horizontal plane parallel to the plane of the roadway obtained by several antennas receiving the reflected waves, the azimuth being determined from the differences in phases between the reflected waves received).

The data thus obtained from the radar(s) having detected an object such as a second vehicle 11 to 13 makes it possible to determine a position of the second vehicle 11 to 13 detected with respect to the first vehicle 10 (i.e. a relative position). The relative position is for example determined from the distance information between the first vehicle 10 and the second vehicle detected, this distance information being obtained from the radar having detected the second vehicle.

According to a variant, the information relating to the radar having detected the second vehicle is also transmitted to the computer in charge of the process. For example, information identifying the radar 101 is for example associated with the distance data obtained between the first vehicle 10 and the second vehicle 12 by this radar 101. This identification information is then transmitted with the distance data to the computer in charge of the radar system.

The activation of the turn signals is for example detected by the computer(s) in charge of the process upon receipt of data or information representative of the activation of one or more turn signals. The flashing lights of the first vehicle 10 are advantageously controlled by one or more computers of the on-board system of the first vehicle 10, which transmit to the computer in charge of the process the information relating to the activation of one or more flashing lights. The vehicle's on-board system includes a set of computers linked together by one or more communication buses. These computers form, for example, a multiplexed architecture for the production of different services useful for the proper functioning of the vehicle and to assist the driver and/or passengers of the vehicle in controlling the vehicle 10. The computers exchange data with each other by intermediary of one or more computer buses, for example a communication bus of the CAN data bus type (from the English “Controller Area Network” or in French “Réseau de controllers”), CAN FD (from the English “Controller Area Network Flexible Data-Rate", FlexRay (according to ISO 17458) or Ethernet (according to ISO/IEC 802-3).

The indicators are for example activated by the driver via one or more flashing light actuating members arranged in the passenger compartment of the first vehicle 10. Control of the activation and deactivation of each of the flashing lights is thus a function of control signals received from the control member(s).

For example, the activation and deactivation of the flashing lights to indicate a change of direction is obtained by actuation of a control lever (corresponding for example to a commodo lever), for example arranged near the steering wheel. For example, moving the control lever from the neutral position upwards controls the activation of the left turn signal lights, moving the control lever from the neutral position downwards controls the activation of the right turn signal lights, returning to the neutral position deactivates the left or right activated indicator lights.

According to another example, a slight upward or downward pressure controls the activation of the left or right turn signals for a determined time interval (for example 1, 2 or 3 seconds), the lever automatically returning to the neutral position and the flashing lights deactivating (i.e. turning off) automatically at the end of the determined time interval.

According to a particular embodiment, the detection of one or more second vehicles is added to the detection of the activation of the indicators (for example on one side of the first vehicle 10 to indicate a change of direction), for example of concomitantly or with a time delay between the two detections, for example equal to 0.5, 1, 2 or 3 seconds.

In a second operation, one or more radars of the radar system of the first vehicle 10 are selected according to the traffic event(s) detected in the first operation.

According to a first example, when the detected event corresponds to the activation of the indicators on one side of the first vehicle, for example on the right (respectively on the left), then the radars selected correspond to those on the right side (respectively on the left side). ) of the first vehicle 10, that is to say the radars 102, 103 (respectively the radars 101, 104).

According to a second example, when the detected event corresponds to the detection of one or more second vehicles, for example the second vehicles 12 and 13, then the selected radars correspond to those having in their coverage zone (the zone covered by the emission of electromagnetic radiation suitable for object detection, which also corresponds to the coverage area for transmission and/or reception of V2V communication signals) the second vehicles 12, 13 detected. Thus, when the second detected vehicle corresponds to vehicle 12, then the left front radar 101 is selected because the second vehicle 12 is in the coverage zone of radar 101. When the second detected vehicle corresponds to vehicle 13, then the front radar right 102 is selected because the second vehicle 13 is in the coverage zone of radar 102.

According to a variant embodiment, the selected radar(s) correspond to the radar(s) having detected the second vehicle(s). The selection of the radar(s) is thus implemented based on the information relating to the radar having detected the second vehicle received from the radar system, this information making it possible to directly identify the radar having the second vehicle detected in its coverage zone. .

In a third operation, data is transmitted by the first vehicle 10 to at least one second vehicle in the road environment 1 via the radar(s) selected according to the vehicle-to-vehicle type communication mode, known as V2V.

For example, when the detected event corresponds to the activation of the indicators on one side of the first vehicle 10, data representative of an alert are for example transmitted to all of the second vehicles potentially traveling on the lane of traffic adjacent to the current lane of the first vehicle and on the side of the current lane corresponding to the side where the activated indicators are located. Such data is transmitted by the radars of the first vehicle on the side corresponding to that of the activated indicators, for example in a broadcast mode. Such data correspond for example to an alert message to alert the second vehicles traveling on this adjacent lane that the first vehicle is going to move towards this adjacent lane. The transmission of such data in broadcast mode via the radars on the side corresponding to that of the lane change of the first vehicle 10 makes it possible to reach all of the second vehicles potentially traveling on this adjacent lane, without the need to detect them individually or to identify them as the recipient of the data. According to another example, the data corresponds to a request issued by the first vehicle 10 to ask the second vehicles traveling on the adjacent lane to leave a free space so that the first vehicle 10 can enter without risk on this adjacent lane.

According to another example, when the detected event corresponds to the detection of a second vehicle, for example the vehicle 12, the data transmitted by the first vehicle in V2V mode via the selected radar 101, correspond for example specifically intended for this second vehicle 12. The data is for example transmitted in unicast mode (or “unicast” in French).

When several second vehicles 12, 13 are detected via for example several radars of the first vehicle 10, the data relating to each second vehicle are for example transmitted in unicast mode to each second vehicle by each radar having detected the second vehicle. For example, the data intended for the second vehicle 12 are transmitted in unicast mode via the radar 101 and the data intended for the second vehicle 13 are transmitted in unicast mode via the radar 102.

When several second vehicles 12, 13 are detected and when the data to be transmitted are the same for each second vehicle, then these data are for example transmitted in multicast (or “multicast” in French) or broadcast mode by all of the selected radars 101, 102.

The selection of several radars according to the detected event(s) makes it possible to implement several simultaneous communications in parallel, a sector or a different spatial communication zone being associated with each radar of the radar system of the first vehicle, due to the distribution spatial radars on the first vehicle 10.

Depending on the radars selected, an overlap of the spatial zones covered by each radar selected is for example obtained. In the overlapping zone, the data transmission range is then greater than that obtained in a spatial zone covered by a single selected radar.

The electromagnetic waves transmitted for data transport according to the V2V communication mode are for example transmitted according to one of the following channel access methods:

- OFDMA, from English “Orthogonal Frequency Division Multiple Access” or in French “Access multiple à division enfrequency orthogonale”;

- TDMA, from English “Time Division Multiple Access” or in French “Access multiple à division dans le temps”;

- CDMA, from English “Code Division Multiple Access” or in French “Access multiple by code division”.

The selection of radars according to one or more traffic events associated with the first vehicle 10 makes it possible to spatially manage the transmission of data, by covering a complete space around the first vehicle 10 thanks to the arrangement and distribution of the radars on the first vehicle 10.

Such an arrangement makes it possible to benefit from the advantages of a mode of communication called “beamforming” (or “spatial filtering” in French), without however having to configure the phase shift between the different radars, as required by this technology. Indeed, such spatial filtering, known to those skilled in the art, is obtained by combining the elements of an array of phased antennas in such a way that in particular directions, the signals interfere constructively while in other directions the interference is destructive.

The invention makes it possible to benefit from certain advantages of “beamforming” (for example more directivity in the emission beams) without implementing this “beamforming” technology which is relatively complex in terms of configuration.

There schematically illustrates a device 2 configured to control the communications implemented through a radar system fitted to a vehicle, according to a particular and non-limiting embodiment of the present invention. The device 2 corresponds for example to a device on board the first vehicle 10 to allow data communication between the first vehicle 10 and one or more second vehicles 11, 12, 13 in V2V communication mode.

The device 2 is for example configured for the implementation of the operations described with regard to the and/or steps of the process described with regard to the . Examples of such a device 2 include, without being limited to, on-board electronic equipment such as an on-board computer of a vehicle, an electronic computer such as an ECU, a telematics control unit TCU (of the English “Telematic Control Unit”), a smartphone (from the English “smartphone”), a tablet, a laptop. The elements of device 2, individually or in combination, can be integrated into a single integrated circuit, into several integrated circuits, and/or into discrete components. Device 2 can be produced in the form of electronic circuits or software (or computer) modules or even a combination of electronic circuits and software modules. According to different particular embodiments, the device 2 is coupled in communication with other similar devices or systems, for example via a communication bus or through dedicated input/output ports.

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

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

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", other devices similar to the device 2 and embedded in vehicles other than the one carrying the device 2. The interface elements of block 22 include one or more of the following interfaces:

- RF radio frequency interface, for example of the Bluetooth® or Wi-Fi® type, LTE (from the English “Long-Term Evolution” or in French “Long-Term Evolution”), LTE-Advanced (or in French LTE-advanced ) ;

- 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);

- LIN interface (from English “Local Interconnect Network”, or in French “Réseau interconnecté local”).

Data is for example loaded to the device 2 via the interface of the block 22 using a Wi-Fi® network such as according to IEEE 802.11, an ITS G5 network based on IEEE 802.11p or a mobile network such as a 4G network (or LTE Advanced according to 3GPP release 10 – version 10) or 5G, in particular an LTE-V2X network.

According to another particular embodiment, the device 2 comprises a communication interface 23 which makes it possible to establish 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. The communication interface 23 corresponds for example to a wired network of the CAN type (from the English “Controller Area Network” or in French “Réseau de controllers”) or CAN FD (from the English “Controller Area Network Flexible Data-Rate” or in French “Network of controllers with flexible data rate”).

According to an additional particular embodiment, the 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 respective interfaces output not shown.

There schematically illustrates a communication system 3 for a vehicle, for example embedded in the first vehicle 10, according to a particular and non-limiting embodiment of the present invention.

The system 3 advantageously comprises the device 2 as described with regard to the in connection with a plurality of radars forming the radar system. According to the example of the , the radar system includes the 4 corner radars 101, 102, 103 and 104 as described with regard to the .

The device 2 is configured to control the radar system, for example as a function of the traffic event(s) detected leading to the selection of one or more radars of the radar system of the first vehicle 10.

Device 2 is connected to the radars via a wired connection, for example via a CAN or CAN FD type data bus or via one or more LIN type buses. According to a variant, the device 2 is connected to the radars 101 to 104 via a wireless interface, for example via Bluetooth® or Wifi®.

Of course, the number of radars in the radar system is not limited to 4 but extends to any number of radars, for example 2, 3, 5, 6, 8, 10 or more radars.

There illustrates a flowchart of the different stages of a communication method implemented by a vehicle carrying a radar system comprising at least one millimeter wave radar, according to a particular and non-limiting embodiment of the present invention. The method is for example implemented by a device on board the first vehicle 10, by the device 2 of the or by system 3 of the .

In a first step 41, at least one event associated with movement of the first vehicle in a road environment is detected.

In a second step 42, at least one radar of the radar system of the first vehicle is selected based on the at least one event detected.

In a third step 43, data is transmitted to at least a second vehicle in the road environment via the at least one radar selected according to a vehicle-to-vehicle type communication mode, called V2V.

According to a variant, the variants and examples of the operations described in relation to Figures 1 to 3 apply to the steps of the process of the .

Of course, the present invention is not limited to the exemplary embodiments described above but extends to a method of controlling a radar system used for the detection of objects and for communications, for example of the V2X type. , and embarked on a vehicle, and to the device configured for the implementation of such a method.

The invention also relates to a vehicle, for example an automobile or more generally a land motor vehicle, comprising the device 2 of the or system 3 of the .

Claims (10)

Communication method for a first vehicle (10), said first vehicle (10) carrying a millimeter wave radar system comprising at least one radar (101 to 104), said method comprising the following steps:
- detection (41) of at least one event associated with circulation of said first vehicle (10) in a road environment (1);
- selection (42) of at least one radar (101, 102) of said radar system based on said at least one detected event;
- transmission (43) of data to at least one second vehicle (12, 13) of said road environment (1) via said at least one selected radar (101, 102) according to a vehicle-to-vehicle type communication mode, says V2V. Method according to claim 1, for which said at least one event belongs to a set of events comprising:
- detection of said at least one second vehicle (12, 13); And
- activation of a turn signal of said first vehicle (10). Method according to claim 2, for which when said event corresponds to said detection of said at least one second vehicle (12, 13), said method comprises a step of determining a position of said at least second vehicle (12, 13) relative to said first vehicle (10), said at least one selected radar (101, 102) corresponding to the radar of said radar system comprising said position in its coverage area for transmission and/or reception of V2V communication signals, each radar of said radar system having a different coverage area. Method according to claim 2 or 3, for which when said event corresponds to said activation of a turn signal, said method comprises a step of determining a side of said first vehicle (10) for which said turn signal is activated, said at least one selected radar being positioned on said side of said first vehicle. Method according to one of claims 2 to 4, for which said radar system comprises 4 corner radars (101 to 104), each corner radar being arranged along an axis forming an angle of 45° relative to a longitudinal axis ( 100) of said first vehicle (10), the coverage area associated with said each radar of said radar system corresponding to an angular sector around said axis. Method according to one of claims 1 to 5, for which each radar (101 to 104) of said radar system is configured for object detection in said road environment and for establishment of at least one communication according to said mode of V2V communication. Computer program comprising instructions for implementing the method according to any one of the preceding claims, when these instructions are executed by a processor. Communication device (2) for a vehicle carrying a millimeter wave radar system comprising at least one radar, said device (2) comprising a memory (21) associated with at least one processor (20) configured for implementing the steps of the process according to any one of claims 1 to 6. Vehicle communications system (3) comprising said device (2) according to claim 8 and a millimeter wave object detection radar system comprising a plurality of radars (101 to 104) spatially arranged on said vehicle and connected to said device (2). Vehicle (10) comprising the device (2) according to claim 8 or said system (3) according to claim 9.