Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
  • G01S13/88—Radar or analogous systems specially adapted for specific applications
  • G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
  • G01S13/931—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of land vehicles
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/27—Adaptation for use in or on movable bodies
  • H01Q1/32—Adaptation for use in or on road or rail vehicles
  • H01Q1/3208—Adaptation for use in or on road or rail vehicles characterised by the application wherein the antenna is used
  • H01Q1/3233—Adaptation for use in or on road or rail vehicles characterised by the application wherein the antenna is used particular used as part of a sensor or in a security system, e.g. for automotive radar, navigation systems
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
  • G01S13/003—Bistatic radar systems; Multistatic radar systems
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
  • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
  • G01S13/50—Systems of measurement based on relative movement of target
  • G01S13/52—Discriminating between fixed and moving objects or between objects moving at different speeds
  • G01S13/536—Discriminating between fixed and moving objects or between objects moving at different speeds using transmission of continuous unmodulated waves, amplitude-, frequency-, or phase-modulated waves
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q21/00—Antenna arrays or systems
  • H01Q21/06—Arrays of individually energised antenna units similarly polarised and spaced apart
  • H01Q21/08—Arrays of individually energised antenna units similarly polarised and spaced apart the units being spaced along or adjacent to a rectilinear path
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
  • B60W2420/00—Indexing codes relating to the type of sensors based on the principle of their operation
  • B60W2420/40—Photo, light or radio wave sensitive means, e.g. infrared sensors
  • B60W2420/408—Radar; Laser, e.g. lidar
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
  • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
  • G01S2013/0236—Special technical features
  • G01S2013/0245—Radar with phased array antenna
  • G01S2013/0254—Active array antenna

Definitions

• Radar system antenna array for a radar system, vehicle with at least one radar system and method for operating at least one radar system Technical field
• the invention relates to a radar system for monitoring at least one surveillance area for objects, with a plurality of transmitting antennas which can be controlled with respective transmission signals and with which corresponding radar signals can be sent into at least one surveillance area, with a plurality of receiving antennas with which Echoes of transmitted radar signals can be received and converted into corresponding received signals, and with at least one control and evaluation device which is connected to the transmitting antennas and the receiving antennas, with which transmit signals for controlling the transmitting antennas are generated and with which object information from with objects detected by the radar signals can be determined.
• the invention relates to an antenna array for a radar system for monitoring at least one monitoring area for objects, with a plurality of transmitting antennas which can be controlled with respective transmission signals and with which corresponding radar signals can be transmitted, and with a plurality of receiving antennas with which echoes received by transmitted Ra darsignalen and can be converted into corresponding received signals.
• the invention also relates to a vehicle with at least one radar system for monitoring at least one monitoring area for objects, with at least one radar system having a plurality of transmitting antennas that can be controlled with respective transmission signals and with which corresponding radar signals are sent into at least one monitoring area can be, a plurality of receiving antennas, with which echoes of transmitted radar signals can be received and converted into corresponding received signals, and at least one control and evaluation device, which is connected to the transmitting antennas and the receiving antennas, with the transmitted signals for controlling the Transmitting antennas are generated and can be used to determine object information from objects detected by the radar signals from received signals.
• the invention also relates to a method for operating a radar system, which is used to monitor at least one monitoring area for objects, with the method controlling a plurality of transmitting antennas with transmission signals and corresponding radar signals being sent into a monitoring area with a plurality of receiving antennas Echoes are received from the transmitted radar signals and converted into corresponding received signals and the Emp catch signals are signal-processed, from the received signals object information about objects in the surveillance area can be determined rich.
• a method for operating a radar device and a radar device are known from DE 10 2018 118 238 A1.
• transmission signals are transmitted into a monitoring area using at least two transmission antenna elements arranged at a distance from one another. If necessary, echo signals reflected by at least one object present in the surveillance area are received with at least one receiving array element. At least one piece of object information is determined from the echo signals.
• the radar device is optionally operated in a range operating mode in which the same transmission signals are transmitted simultaneously with the at least two transmitting antenna elements and a distance and/or a speed of the at least one object relative to the radar device is determined from the corresponding echo signals, or in a directional operating mode in which the at least two transmitting antenna elements are used to transmit distinguishable transmission signals, which are assigned correspondingly distinguishable echo signals to the transmitting antenna elements and at least one direction component of the object is determined.
• the object of the invention is to design a radar system, an antenna array, a vehicle and a method of the type mentioned at the outset, in which the performance of the radar system is improved in relation to the detection range of the radar system and the angular resolution when determining a direction.
• this object is achieved in the radar system in that the respective phase centers of at least four receiving antennas are arranged on an imaginary receiver longitudinal axis, the respective phase centers of at least two adjacent receiving antennas being arranged at a base distance from one another and the respective phase centers of at least two adjacent receiving antennas are arranged at a respective receiver longitudinal distance from one another which is greater than the base distance.
• four receiving antennas are arranged next to one another along an imaginary longitudinal axis of the receiver. At least two receiving antennas are arranged at a base distance. In this way, unambiguous direction determinations can be made with the receiving antennas. At least two receiving antennas are spaced apart. In this way, the receiving antenna arrangement can be made larger overall. In this way, the aperture of the radar system can be increased.
• the receiving antenna arrangement according to the invention can be used both for using the radar system in a directional operating mode in which the transmitting antennas are controlled with different transmission signals and in a range operating mode in which the transmitting antennas are controlled with the same transmission signal.
• At least one longitudinal distance between the receivers can be an integer multiple of the base distance, in particular plus or minus a tolerance.
• the expansion of the receiving antennas can be increased order in the direction of the longitudinal axis of the receiver.
• a correspondingly large virtual receiving antenna array which is gebil det from the transmitter arrangement and the receiver arrangement, allow a correspondingly large aperture.
• phase centers of two receiving antennas located on the outside of the longitudinal axis of the receiver can be arranged at the base distance. In this way, a corresponding virtual receiving antenna array can be implemented in the directional operating mode of the radar system, which enables better angular resolution.
• the phase centers of at least two mutually adjacent receiving antennas can be arranged on the same side of the phase centers of two receiving antennas arranged at a base distance, with a longitudinal receiver distance between the phase center of the receiving antenna that is associated with the two receiving antennas arranged at a base distance is closest, and the phase center of the closest of the two base-spaced receive antennas may be less than a receiver longitudinal distance between the phase center of the receive antenna closest to the two base-spaced receive antennas and the phase center of the receive antenna, which is located ent to the two base-spaced receiving antennas ent, or wherein a receiver longitudinal distance between the phase center of the receiving antenna which is closest to the two base-spaced receiving antennas and the phase center of the nearest of the two base-spaced receive antennas may be greater than a receiver longitudinal separation between the phase center of the receive antenna nearest to the two base-spaced receive antennas and the phase center of the receive antenna nearest to the two base-spaced receive antennas arranged receiving antennas ent is located away.
• a virtual receiving antenna array can be implemented in the directional operating mode of the radar system, which combines a large aperture with a large angular resolution. If the receiver longitudinal spacing of the nearest receiving antenna is smaller than the receiver longitudinal spacing of the remote receiving antenna, the receiving antenna arrangement can be made more compact.
• the base distance and the two longitudinal distances can advantageously be arranged according to the markings on a Golomb ruler.
• a correspondingly expanded virtual receiving antenna array can be implemented in the directional operating mode of the radar system, with which a correspondingly large win kelresolution is made possible. In this case, a larger aperture can be made possible in the range operating mode of the radar system.
• a quotient of a larger of two receiver longitudinal distances between three adjacent receiving antennas and a smaller of the two receiver longitudinal distances can be 1.5 or an integer multiple of 1.5. In this way, the clarity of the angle measurement can be improved.
• a quotient of a larger of two receiver longitudinal distances between three adjacent receiving antennas and a smaller of the two receiver longitudinal distances can be twice 1.5, ie three.
• the base distance can correspond to half the wavelength of the radar signals transmitted with the transmitting antennas, in particular plus or minus a tolerance. In this way, in a directional operating mode of the radar system, clearly directed radar signals can be implemented on the transmitter side. In addition, in the direction mode of operation, unambiguous angle measurements can be carried out.
• At least one transmitting antenna can advantageously have a plurality of antenna elements. In this way, the transmission properties of the at least one transmission antenna to be improved.
• at least one receiving antenna can advantageously have a plurality of antenna elements. In this way, the receiving properties of the at least one receiving antenna can be improved.
• the phase centers of the transmission antennas can advantageously be arranged in a transmission antenna plane. In this way, the positions of the phase centers can be defined more easily. In this way, more precise radar measurements can be carried out.
• the main radiation directions of the transmission antennas can run perpendicular to the plane of the transmission antenna. In this way, the main beam directions can be defined more easily.
• the phase centers of the receiving antennas can advantageously be arranged in one receiving antenna plane. In this way, the positions of the phase centers can be defined more easily. In this way, more precise radar measurements can be carried out.
• the main reception directions of the reception antennas can advantageously run perpendicular to the plane of the reception antenna. In this way, the main reception directions can be defined more easily.
• phase centers of the transmitting antennas and the phase centers of the receiving antennas can advantageously be arranged in a common antenna plane. In this way, the positions of the phase centers can be arranged more precisely.
• At least some of the transmitting antennas can be realized as an antenna array.
• the transmitting antennas can be manufactured and installed together.
• At least part of the receiving antennas can advantageously be implemented as an antenna array. In this way, the receiving antennas can be manufactured and assembled together.
• at least some of the transmitting antennas and at least some of the receiving antennas can advantageously be implemented as a common antenna array. In this way, the transmitting antennas and the receiving antennas can be manufactured and assembled together.
• the respective phase centers of at least two adjacent transmitting antennas can advantageously be arranged on an imaginary longitudinal axis of the transmitter and the phase center of at least one further transmitting antenna can be arranged at a transverse distance from the transmitter to the longitudinal axis of the transmitter.
• an imaginary transmitter transverse axis which runs perpendicular to the transmitter longitudinal axis through the phase center of the at least one further transmitting antenna, can be spaced at a base distance from an imaginary transmitter transverse axis, which runs perpendicular to the transmitter longitudinal axis through the phase center of one of the at least two Transmitting antennas runs on the longitudinal axis of the transmitter.
• a transmitter longitudinal distance between the respective imaginary transmitter transverse axes of the at least two adjacent transmitter antennas on the transmitter longitudinal axis can advantageously be greater than the base distance.
• At least two transmitting antennas can be arranged along a longitudinal axis of the transmitter. At least one further transmission antenna can be arranged next to the longitudinal axis of the transmitter. The at least one transmitting antenna, which is arranged next to the longitudinal axis of the transmitter, can also be found at the base distance next to the corresponding transmitter transverse axis of at least one of the two other transmitting antennas.
• the advantageous transmission antenna arrangement can be operated both in a directional operating mode, in which the transmitting antennas can be controlled with different transmission signals, and in a range operating mode, in which the transmitting antennas can be controlled with the same transmission signal.
• the longitudinal distance between the transmitters can be an integer multiple of the base distance, in particular plus or minus a tolerance
• the transverse spacing of the transmitter can advantageously be greater than the base spacing
• the transverse spacing of the transmitter can advantageously be smaller than the longitudinal spacing of the transmitter.
• a particularly compact transmission antenna arrangement can be implemented in this way.
• the transverse axis of the transmitter of the at least one further transmission antenna can advantageously be arranged between the transverse axes of the transmitter of the at least two transmission antennas that are adjacent to the longitudinal axis of the transmitter. In this way, the transmitting antenna arrangement can be made even more compact.
• At least some of the transmission antennas can be controlled at least temporarily with the same transmission signal.
• At least some of the transmitting antennas can advantageously be controlled at least temporarily with different transmission signals in such a way that the respectively transmitted radar signals can be distinguished at least temporarily, at least on the side of the receiving antennas.
• At least some of the transmission antennas can advantageously be controllable in a switchable manner using the same transmission signal or different transmission signals.
• the corresponding transmitting antennas can simultaneously emit the same radar signals.
• the radar signals from the individual transmitting antennas can be combined to form a common radar signal with greater signal strength. In this way, the detection range can be increased.
• the operating mode of the radar system in which at least some of the transmission antennas are controlled with the same transmission signal, can be referred to as the range operating mode will.
• At least two adjacent transmission antennas can advantageously be operated using a beamforming method.
• the same radar signal can be transmitted with defined phase offsets from a plurality of transmission channels in each case coherently via adjacent transmission antennas, which are arranged in particular at the base distance.
• the ability to distinguish between the radar signals enables the corresponding echoes of the radar signals, which are received with the receiving antennas, to be assigned to the corresponding transmitting antennas. In this way, the amount of transmission antennas required for determining the direction can be reduced.
• the operating mode of the radar system in which at least two of the transmitting antennas are controlled in such a way that the respective transmitted radar signals can be distinguished at least temporarily, at least on the side of the receiving antennas, can be referred to as the directional operating mode.
• At least two of the transmitting antennas can advantageously be operated using a MIMO method.
• respective radar signals are transmitted by the transmitting antennas, which are at least temporarily distinguishable at least on the receiving antenna side. In this way, the angular resolution can be improved when determining the direction.
• the fact that at least some of the transmission antennas can be controlled in a switchable manner with the same transmission signal or different transmission signals means that the radar system can be switched between the directional operating mode and the range operating mode.
• at least some of the transmitting antennas can be switched over automatically and/or as required.
• the radar system in particular at least one control and evaluation device of the radar system, can have at least one switching device with which the radar system can be switched between an operating mode in which at least some of the transmitting antennas can be controlled with the same transmitting signal, in particular a range operating mode or beamforming mode, and an operating mode in which at least some of the transmission antennas can be controlled with different transmission signals, in particular a direction mode or MIMO mode, can be switched over.
• a virtual receiving antenna array can be realized when operating the radar system in a direction operating mode, in particular a MIMO mode, which has a large aperture with a large angular resolution combined.
• Object information in particular distances, directions and/or speeds of objects, in particular object targets, can be determined relative to the radar system with the radar system.
• Object targets are areas of objects where a reflection of radar signals takes place, which can be received as echoes with the receiving antennas.
• Direction determination The determination of the direction in which a target is relative to the radar system.
• the direction can be specified as an angle relative to a reference axis of the radar system, in particular a main beam direction of the transmitting antennas.
• the longitudinal axis of the transmitter and/or the longitudinal axis of the receiver and the main beam directions of the transmitting antennas can be spatially aligned horizontally.
• a horizontally extending surveillance area can be monitored with angular resolution.
• the direction can be determined as an azimuth.
• the radar system can advantageously have means for controlling the transmission antennas, in particular for generating transmission signals. Furthermore, the radar system Have means for processing the received signals.
• the means for controlling and/or for processing can be implemented with a common control and evaluation device using software and/or hardware.
• the control and evaluation device can have corresponding transmission channels for the transmission signals and/or reception channels for the reception signals.
• the transmission signals and/or the reception signals can be electrical signals. In this way, electronic means can be used for control and/or evaluation.
• the invention can be used in a radar system of a vehicle, particularly a motor vehicle.
• the invention can advantageously be used in a land vehicle, in particular a passenger car, a truck, a bus, a motorcycle or the like, an aircraft and/or a watercraft.
• the invention can also be used in vehicles that can be operated autonomously or at least partially autonomously.
• the invention is not limited to vehicles. It can also be used in stationary radar systems.
• the radar system can advantageously be connected to at least one electronic control device of the vehicle, in particular a driver assistance system and/or chassis control and/or driver information device and/or a parking assistance system and/or gesture recognition or the like, or be part of such.
• a driver assistance system and/or chassis control and/or driver information device and/or a parking assistance system and/or gesture recognition or the like or be part of such.
• the vehicle can be operated autonomously or semi-autonomously.
• the radar system can be used to detect stationary or moving objects, in particular vehicles, people, animals, plants, obstacles, bumps in the road, in particular potholes or stones, road boundaries, traffic signs, open spaces, in particular parking spaces, precipitation or the like.
• a virtual receiving antenna array can be implemented in a directional operating mode of the radar system with the arrangement of the transmitting antennas and the receiving antennas, in which at least two adjacent virtual receiving array elements are arranged on at least one imaginary array longitudinal axis be able, wherein at least two adjacent virtual receiving array elements can be arranged at the base distance from each other and/or wherein at least two adjacent virtual receiving array elements can be arranged at a distance that is greater than the base distance and/or wherein at least two adjacent virtual receiving array elements in can be arranged at a distance that corresponds to an integer multiple of the base distance.
• the virtual reception array elements which are arranged at a basic distance from one another, a clear determination of the direction can be implemented.
• a larger virtual reception antenna array can be implemented overall.
• a larger aperture can be realized with a larger virtual receiving antenna array.
• the direction of target objects can be determined clearly and more precisely with the radar system in a correspondingly large angular range.
• a virtual receiving antenna array with a large number of virtual receiving array elements can be achieved by geometric folding of the positions of the phase centers of transmitting antennas and the positions of the phase centers of the receiving antennas.
• the virtual receiving array elements can be arranged distributed on at least two imaginary array longitudinal axes in the virtual receiving antenna array, with at least two virtual receiving array elements, which are arranged on different Ar ray longitudinal axes, in the direction of the Array longitudinal axes can be arranged at the same height and/or wherein at least two virtual receiving array elements, which are arranged on different Ar ray longitudinal axes, can be arranged offset from one another when viewed in the direction of the array longitudinal axes and/or wherein at least two virtual receiving array elements, which are arranged on different array longitudinal axes, viewed in the direction of the array longitudinal axis can be arranged offset in the base distance from one another.
• directions of target objects can be determined in two dimensions.
• the staggered arrangement of the virtual receiving array elements allows better angular resolution to be achieved when determining the direction of target objects.
• the object is achieved according to the invention with the antenna array in that the respective phase centers of at least four receiving antennas are arranged on an imaginary receiver longitudinal axis, the respective phase centers of at least two adjacent receiving antennas being arranged at a base distance from one another and the respective phase centers of at least two adjacent receiving antennas are arranged at a respective receiver longitudinal distance from one another which is greater than the base distance.
• the object is achieved according to the invention in the vehicle in that the vehicle has at least one radar system according to the invention.
• the vehicle has at least one radar system with which the surroundings of the vehicle can be monitored for objects.
• Object information which is determined with the at least one radar system, can be used with a driver assistance system to control the operation of the vehicle. In this way, the vehicle can be operated autonomously or semi-autonomously.
• the object is achieved according to the invention in the method in that there is a switchover between at least two radar measurements between a range operating mode in which at least some of the transmitting antennas are controlled at least temporarily with the same transmission signal, and a directional operating mode in which at least some of the transmitting antennas are at least temporarily controlled with different transmission signals in such a way that the respectively transmitted radar signals can be distinguished at least temporarily at least on the side of the receiving antennas.
• the radar system is operated alternately in the range operating mode to achieve large detection ranges and in the directional operating mode to increase the angular resolution when determining the direction.
• the reflected radar signals i.e. the echoes
• the reflected radar signals can be assigned to the respective transmitting antennas on the receiving antenna side.
• differently coded radar signals can be transmitted with at least two transmitting antennas.
• the radar signals can be distinguished from one another at least temporarily on the receiving antenna side.
• the transmission signals for generating the distinguishable radar signals can be encoded with respect to one another, in particular by means of phase modulations.
• an at least temporary orthogonality in terms of signaling technology can be achieved between the transmission signals and the reception signals.
• the radar signals and the corresponding echoes can be distinguished from one another.
• the received signals can be processed on the receiver side by appropriate evaluation, in particular with the help of Fourier transformations.
• Means for carrying out the evaluation can advantageously be implemented in the form of software and/or hardware, in particular in the at least one control and evaluation device.
• FIG. 1 shows a front view of a motor vehicle with a driver assistance system and a radar system for monitoring a monitoring area in front of the motor vehicle in the direction of travel;
• FIG. 2 shows a plan view of the motor vehicle from FIG. 1;
• FIG. 3 shows a side view of the motor vehicle from FIGS. 1 and 2;
• FIG. 4 shows a front view of an antenna array of the radar system with transmitting antennas and receiving antennas according to a first exemplary embodiment, which can be used in the motor vehicle from FIGS. 1 to 3;
• FIG. 5 shows a virtual receiving antenna array which is implemented when operating the radar system in a directional operating mode with the antenna array from FIG. 4;
• FIG. 6 shows a range/direction diagram of the antenna array from FIG. 4, in which the detection range of the radar system is shown as a function of the direction when the radar system is operated in a range operating mode and in a directional operating mode;
• FIG. 7 shows a reception signal direction diagram of the antenna array from FIG. 4 when a target object is detected, with the radar system being operated in the direction operating mode
• FIG. 8 shows a reception signal direction diagram with a large number of measurement curves of the antenna array from FIG. 4 when two target objects are detected, with the radar system being operated in the direction operating mode;
• FIG. 9 shows a received signal direction diagram of the antenna array from FIG. 4 when detecting the two target objects from FIG. 8, with the radar system being operated in the range operating mode;
• FIG. 10 shows a front view of an array with transmitting antennas and receiving antennas of a radar system according to a second exemplary embodiment, which can be used in the motor vehicle from FIGS. 1 to 3;
• FIG. 11 shows a virtual receiving antenna array which is implemented when operating the radar system in a directional operating mode with the antenna array from FIG. 10;
• FIG. 12 shows a range-direction diagram of the antenna array from FIG. 10, in which the detection range is shown as a function of the direction when the radar system is operated in the range operating mode and in the directional operating mode;
• FIG. 13 shows a received signal direction diagram of the antenna array from FIG. 10 when detecting a target object, with the radar system being operated in the directional operating mode;
• FIG. 14 shows a reception signal direction diagram with a large number of measurement curves of the antenna array from FIG. 10 when two target objects are detected, with the radar system being operated in the direction operating mode;
• FIG. 15 shows a received signal direction diagram of the radar system with the antenna array from FIG. 10 when detecting the two target objects from FIG. 14, the radar system being operated in the range operating mode.
• FIG. 1 shows a front view of a motor vehicle 10 in the form of a passenger car.
• FIG. 2 shows motor vehicle 10 in a plan view.
• Figure 3 the motor vehicle 10 is shown in a side view.
• the motor vehicle 10 has a radar system 12.
• the radar system 12 is arranged in the front bumper of the motor vehicle 10, for example. With the radar system 12, a monitoring area 14 in the direction of travel 16 in front of the motor vehicle 10 can be monitored for objects 18.
• the radar system 12 can also be arranged at a different location on the motor vehicle 10 and oriented differently.
• the radar system 12 can be used to determine object information, for example distances r and directions, for example in the form of the azimuth cp and the elevation Q, of object targets of objects 18 relative to the motor vehicle 10 or the radar system 12 .
• speeds of object targets relative to motor vehicle 10 can also be determined.
• Object targets of an object 18 are parts of the object 18 on which radar beams can be reflected and sent back as echoes.
• the objects 18 can be stationary or moving objects, for example other vehicles, people, animals, plants, debris, bumps in the road, for example potholes or stones, road boundaries, traffic signs, open spaces, for example parking spaces, precipitation or the like.
• the corresponding coordinate axes of a Cartesian x-y-z coordinate system are shown in FIGS. 1 to 5, 10 and 11.
• the x-axis extends in the direction of a vehicle longitudinal axis of the motor vehicle 10
• the y-axis extends along a vehicle transverse axis
• the z-axis extends spatially upwards perpendicularly to the x-y plane.
• the x-axis and y-axis extend horizontally in space and the z-axis extends vertically in space.
• the radar system 12 is designed as a frequency-modulated continuous wave radar. Frequency-modulated continuous wave radars are also known in specialist circles as FMCW (Frequency modulated continuous wave) radars.
• the radar system 12 can be used to detect objects 18 at large distances r with large angular resolutions in terms of azimuth Q and elevation cp.
• the radar system 12 is connected to a driver assistance system 20 .
• Motor vehicle 10 can be operated autonomously or partially autonomously with driver assistance system 20 .
• the radar system 12 includes an antenna array 22 and a control and evaluation device 24.
• FIG. 4 shows an antenna array 22 according to a first exemplary embodiment.
• FIG. 10 shows an antenna array according to a second exemplary embodiment
• the radar system 12 in connection with the antenna array 22 according to the first exemplary embodiment in connection with FIGS. 4 to 9 will first be described below.
• the antenna array 22 has, for example, three transmitting antennas 26 and four receiving antennas 28.
• the receiving antennas 28 are arranged spatially below the transmitting antennas 26.
• the receiving antennas 28 can also be arranged above, next to or at least partially on the same level, for example between the transmitting antennas 26 .
• Each transmit antenna 26 is connected to a corresponding transmit channel.
• the respective transmission antennas 26 can be controlled with corresponding electrical transmission signals via the transmission channels.
• each receiving antenna 28 is connected to a corresponding receiving channel. Electrical reception signals can be transmitted from the reception antennas 28 via the reception channels.
• the transmission channels and the reception channels can be integrated into the control and evaluation device 24, for example.
• Corresponding radar signals 30 can be sent with the transmitting antennas 26 by activation with the electrical transmission signals.
• the position of each transmit antenna 26 is defined by its respective phase center 32 .
• the respective phase centers 32 of two of the transmitting antennas 26 are arranged adjacent on an imaginary longitudinal axis 34 of the transmitter.
• the transmitter longitudinal axis 34 for example, extends parallel to the y-axis.
• the phase center 32 of the third transmitting antenna 26 is arranged next to, in FIG. 4 below, the longitudinal axis 34 of the transmitter.
• the third transmitting antenna 26 is located at a transmitter transverse distance 36 from the transmitter longitudinal axis 34.
• a corresponding imaginary transmitter transverse axis 38 runs through the phase centers 32 of the three transmission antennas 26.
• the transmitter transverse axes 38 extend perpendicularly to the transmitter longitudinal axis 34, for example parallel to the z-axis.
• the transmitter transverse axis 38 of the individual transmission antenna 26 is arranged between the transmitter transverse axes 38 of the two transmission antennas 26 adjacent to the transmitter longitudinal axis 34 .
• the transmitter transverse axis 38 of the individual transmitting antenna 26 runs at a base distance 40 from the transmitter transverse axis 38 of the transmitting antenna 26 on the right in Figure 4 on the transmitter longitudinal axis 34.
• the base distance 40 corresponds, for example, to half the wavelength l of the transmitting antennas 26 transmitted radar signals 30, optionally plus or minus a tolerance.
• a transmitter longitudinal spacing 42 between the respective transmitter transverse axes 38 of the two transmitting antennas 26 on the transmitter longitudinal axis 34 is three times the base spacing 40, optionally plus or minus a tolerance.
• Transverse transmitter spacing 36 is less than longitudinal transmitter spacing 42 and greater than base spacing 40.
• the antenna array 22 has, for example, four receiving antennas 28 . Echoes 44 of transmitted radar signals 30 can be received with the receiving antennas 28 and converted into corresponding electrical received signals.
• the phase centers 32 of the transmitting antennas 26 and the phase centers 32 of the receiving antennas 28 are arranged, for example, in a common antenna plane.
• the antenna plane extends, for example, parallel to the yz plane.
• the main beam directions of the transmitting antennas 26 run, for example, perpendicularly to the antenna plane, ie parallel to the longitudinal axis of the vehicle or parallel to the x-axis.
• the main receiving directions of the receiving antennas 28 likewise run perpendicularly to the antenna plane, for example.
• the respective phase centers 32 of the receiving antennas 28 are arranged on an imaginary longitudinal axis 46 of the receiver.
• the longitudinal axis of the receiver 46 runs parallel to the longitudinal axis of the transmitter 34.
• phase centers 32 in FIG. 4, viewed from the left, of the first and the second receiving antenna 28 are arranged at the base distance 40 from one another. With the aid of the two receiving antennas 28 arranged at a base distance 40, unambiguous direction determinations for object targets can be made.
• the phase centers 32 of the third and fourth reception antennas 28 are arranged on the same side of the phase centers 32 of the two reception antennas 28 arranged at the base distance 40 .
• the phase center 32 of the second receiving antenna 28 from the left in FIG. 4 is arranged at a first receiver longitudinal distance 48a from the phase center 32 of the third receiving antenna 28 from the left.
• the first longitudinal receiver distance 48a is twice the base distance 40, optionally plus or minus a tolerance.
• the phase center 32 of the third receiving antenna 28 from the left in FIG. 4 is arranged at a second receiver longitudinal distance 48b from the phase center 32 of the fourth receiving antenna 28 from the left.
• the second longitudinal receiver spacing 48b is six times the base spacing 40, optionally plus or minus a tolerance.
• the quotient of the second receiver longitudinal distance 48b and the first receiver longitudinal distance 48a is three.
• the base distance 40 and the two receiver longitudinal distances 48a and 48b can be arranged according to the markings on a Golomb ruler.
• a correspondingly large aperture of the radar system 12 is realized in the direction of the azimuth cp.
• a virtual receiving antenna array 50 shown in Figure 5 can be implemented in the directional operating mode of the radar system 12, which has a large aperture with a large angular resolution in Direction of azimuth cp combined.
• the receiving array elements 52 are achieved, for example, by a geometric convolution of the positions of the phase centers 32 of transmitting antennas 26 and the positions of the phase centers 32 of the receiving antennas 28 .
• the virtual reception antenna array 50 has a total of twelve virtual reception array elements 52 .
• the receiving array elements 52 are arranged distributed on a first imaginary array longitudinal axis 54a and a second imaginary array longitudinal axis 54b. Due to the distributed arrangement of the receiving array elements 52 on the array longitudinal axes 54a and 54b, directions of target objects can be measured in two spatial dimensions, namely in the direction of the y-axis, or azimuth cp, and the z-axis, or elevation Q, be determined.
• the receiving array elements 52 are, for example, in a common array plane. For example, the array plane extends parallel to the y-z plane.
• Six of the receiving array elements 52 are arranged on a first imaginary array longitudinal axis 54a.
• the first and the second receiving array element 52, the third and the fourth receiving array element 52 and the fourth and the fifth receiving array element 52 are on the first array longitudinal axis 54a, each in the base stood arranged 40 to each other.
• the reception array elements 52 which are arranged at a base distance of 40 from one another, an unambiguous determination of the direction can be realised.
• Figure 5 viewed from the left are the second and third receiving array elements 52, the fifth and sixth receiving array elements 52, the sixth and seventh receiving array elements 52 and the seventh and eighth receiving array elements 52 on the first Array longitudinal axis 54a are arranged at a first distance 56a from one another.
• the first distance 50a corresponds to twice the base distance 40.
• a second distance 56b between the seventh and the eighth reception array element 52 corresponds to four times the base distance 40.
• the second array longitudinal axis 54b runs parallel to the first array longitudinal axis 54a in the array plane.
• the two array longitudinal axes 54a and 54b extend parallel to the y-axis.
• the first receiving array element 52 on the second array longitudinal axis 54b viewed from the left in FIG. 5 is arranged at the same height as the third receiving array element 52 on the first array longitudinal axis 54a viewed in the direction of the array longitudinal axes 54a and 54b.
• the second reception array element 52 from the left on the second array longitudinal axis 54b is arranged at the same height as the fourth reception array element 52 on the first array longitudinal axis 54a, viewed in the direction of the array longitudinal axes 54a and 54b.
• the third receiving array element 52 on the second longitudinal axis 54b of the array viewed from the left in FIG 54a, i.e. offset to these, each arranged at a base distance of 40.
• the fourth receiving array element 52 on the second longitudinal array axis 54b viewed from the left in FIG. 5 is between the seventh and the eighth receiving array element 52 on the first longitudinal array axis 54a, ie offset from these, arranged at a base distance 40 from the eighth receiving array element 52 .
• the first and the second receiving array element 52 are arranged at a base distance 40 from one another on the second array longitudinal axis 54b.
• the second and the third reception array element 52 on the second array longitudinal axis 54b are arranged at the first distance 56a from one another, which corresponds to twice the base distance 40 .
• the third and the fourth reception array element 52 on the second array longitudinal axis 54b are arranged at a third distance 56c from one another, which corresponds to six times the base distance 40.
• the aperture of the radar system 12 in the direction of the longitudinal axes 54a and 54b, ie in the direction of the y-axis, is defined by the maximum width of the virtual receiving antenna array 50.
• FIG. The maximum width of the virtual reception antenna array 50 in the direction of the array longitudinal axes 54a and 54b is given by a distance 56d between the two outer reception array elements 52 on the first array longitudinal axis 54 .
• the distance 56d between the two outer receiving array elements 52 corresponds to twelve times the base distance 40.
• the offset arrangement of the reception array elements 52 on the two array longitudinal axes 54a and 54b allows a better angular resolution when determining the direction of target objects both in azimuth cp and in elevation Q to be achieved.
• the control and evaluation device 24 is implemented in terms of software and hardware.
• the control and evaluation device 24 is connected to the transmitting antennas 26 and the receiving antennas 28 .
• the control and evaluation device 24 can be used to generate electrical transmission signals for controlling the transmission antennas 26 .
• object information from the radar signals 30 detected objects 18 are determined.
• the radar system 12 can be switched between a range mode of operation and a direction mode of operation.
• the transmission antennas 26 can be controlled in a switchable manner with the same transmission signal or with different transmission signals.
• the receiving antennas 28 can be switched between the range mode of operation and the directional mode of operation.
• Switching from the range operating mode to the directional operating mode can take place automatically or on demand.
• a higher angular resolution is possible when determining the direction than in the range mode of operation.
• a greater detection range is possible in the range operating mode than in the directional operating mode.
• the control and evaluation device 24 has a switching means 58 with which the radar system 12 can be switched between the range-Be operating mode and the directional operating mode.
• the transmission antennas 26 can be controlled with the same transmission signal. By controlling the transmitting antennas 26 with the same transmission signal, the corresponding transmitting antennas 26 can emit the same radar signals 30 simultaneously.
• the transmitting antennas 26 can be operated according to a so-called beamforming method. In this case, a plurality of transmission channels can each transmit the same radar signal 30 coherently via adjacent transmission antennas 26 with defined phase offsets. The signal strengths of the radar signals 30 of the individual transmission antennas 26 add up to a greater signal strength. In this way, the detection range can be increased.
• Radar measurements are carried out continuously with the radar system 12 in order to monitor the monitoring area 14 for objects 18 .
• Each radar measurement includes a range measurement sequence in which the radar system 12 is operated in the range mode of operation and a bearing measurement sequence in which the radar system 12 is operated in the bearing mode of operation.
• the radar system 12 is switched from the range mode of operation to the direction mode of operation switched.
• Each radar measurement can start with the range measurement sequence or with the direction measurement sequence.
• a radar measurement is described as an example, which begins with a range measurement sequence.
• the control and evaluation device 24 controls the transmission antennas 26 with the same transmission signal via the respective transmission channels.
• the transmitting antennas 26 each transmit the same radar signal 30 simultaneously.
• the signal strengths of the individual radar signals 30 add up and are sent together with an increased detection range into the monitoring area 14 .
• the radar signals 30 hit an object 18, the radar signals 30 are reflected at corresponding object targets.
• the echoes 44 of the reflected radar signals 30 are received with the receiving antennas 28 and converted into respective received signals.
• the received signals are transmitted to the control and evaluation device 24 and processed with it in terms of signal technology, for example by means of Fourier transformations.
• the object information about the objects 18, namely the distances r, the directions, namely azimuth cp and elevation Q, and optionally the speeds of the detected target objects relative to the radar system 12 are determined from the received signals.
• the radar system 12 is then switched over, for example with the control and evaluation device 24, from the range operating mode to the directional operating mode and a directional measurement sequence is carried out.
• the control and evaluation device 24 controls the transmission antennas 26 via the respective transmission channels with different transmission signals.
• the different transmission signals are coded to each other.
• the transmitter antennas 26 transmit radar signals 30 coded in accordance with one another.
• the radar signals 30 are sent to the surveillance area 14 . If the distinguishable radar signals 30 hit an object 18, the radar signals 30 are reflected at the corresponding object targets.
• the echoes 44 of the reflected, distinguishable radar signals 30 are received with the receiving antennas 28 and converted into respective received signals.
• the received signals are transmitted to the control and evaluation device 24 .
• the received signals are assigned to the transmitting antennas 26, which is possible because of the differentiability of the radar signals 30 and the echoes 44.
• the assigned reception signals are processed in terms of signal technology, for example by means of Fourier transformations.
• the object information about the objects 18, namely distances r, the directions, namely azimuth cp and elevation Q, and optionally the speeds of the detected target objects relative to the radar system 12 are determined from the received signals.
• the object information of object targets is determined in larger detection ranges in the range measurement sequence than in the direction measurement sequence.
• the object information from object targets is determined with a lower detection range than in the range measurement sequence, but with a higher angular resolution than in the range measurement sequence.
• FIG. 6 shows a range-direction diagram 60a for the radar system 12 in the range operating mode with dashed lines and a range-direction diagram 60b for the radar system 12 in the directional operating mode with a solid line.
• the respective ranges are recorded via azimuth cp.
• the radar system 12 has a maximum detection range of approximately 250 m in the range operating mode. In the directional operating mode, however, the radar system 12 only has a maximum detection range of slightly less than 200 m. In contrast, the radar system 12 has a larger field of view in the direction of azimuth cp in the directional operating mode than in the range operating mode.
• FIG. 7 shows an example of a received signal direction diagram 62a from a direction measurement sequence in which a target object was detected at an azimuth cp of 0° in front of motor vehicle 10.
• the sidelobe level is at about 8 dB. this is sufficient to resolve target objects with different reflectivities, for example in realistic driving situations with motor vehicle 10, with regard to their direction, namely the respective azimuth cp.
• a family of received signal direction diagrams 62b of several direction measurement sequences is shown as an example, in which two target objects, which have the same distance r and the same speed relative to the radar system 12, at an angular distance of about 11 ° by a Azimuth cp of 0° in front of the motor vehicle 10 were detected.
• the curves of the group of reception signal direction diagrams 62b correspond to different phase differences of the transmission signals.
• the two targets can be distinguished at all possible phase differences.
• the curves of the family of received signal direction diagrams 62b can be determined, for example, using a so-called beamforming approach and/or so-called super-resolution methods or the like.
• a received signal direction diagram corresponding to the direction measurement sequence from FIG. 8 in a range measurement sequence is shown in FIG.
• the angular resolution related to the azimuth cp is about 11°.
• the sidelobe level in this case is around 3dB, which is insufficient to resolve the two targets in the range mode of operation.
• FIG. 10 shows an antenna array 22 for the radar system 12 according to a second exemplary embodiment.
• Figure 11 shows the virtual receiving antenna array 50 belonging to the antenna array 22 from Figure 10.
• the second exemplary embodiment differs from the first exemplary embodiment in that the phase center 32 of the second receiving antenna 28 from the left is arranged at a receiver longitudinal distance 48c from the phase center 32 of the third receiving antenna 28 from the left.
• the longitudinal receiver spacing 48c is three times the base spacing 40, optionally plus or minus a tolerance.
• the phase center 32 of the third receiving antenna 28 from the left in FIG. 10 is arranged at the receiver longitudinal distance 48a from the phase center 32 of the fourth receiving antenna 28 from the left.
• the longitudinal receiver spacing 48a is twice the base spacing 40, optionally plus or minus a tolerance.
• the quotient of the longitudinal distance 48c and the longitudinal distance 48a is 1.5.
• the virtual receiving antenna array 50 according to the second exemplary embodiment from Figure 11 differs from the virtual receiving antenna array 50 according to the first exemplary embodiment from Figure 5 in that the virtual receiving antenna array 50 according to the second exemplary embodiment has only 11 receiving antennas 28 has, of which only seven are arranged on the first array longitudinal axis 54a.
• the third receiving array element 52 is arranged from the left on the first array longitudinal axis 54a at a distance 56e from the second receiving array element 52 from the left, which corresponds to three times the base distance 40.
• the seventh receive array element 52 from the left is the rightmost receive array element 52 on the first array longitudinal axis 54a.
• the maximum width of the virtual receiving antenna array 50 corresponds to a distance 56f between the left receiving array element 52 and the right receiving array element 52.
• the distance 56f corresponds to ten times the base distance 40.
• the first receiving array element 52 on the second array longitudinal axis 54b in the direction of the array longitudinal axes 54a and 54b is between the second and the third receiving array element 52 on the first array longitudinal axis 54a, i.e. offset this, in the base distance 40 to the third receiving array element 52 arranged.
• the second reception array element 52 on the second array longitudinal axis 54b viewed from the left is arranged at the same height as the third reception array element 52 on the first array longitudinal axis 54a viewed in the direction of the array longitudinal axes 54a and 54b.
• the fourth reception array element 52 on the second array longitudinal axis 54b viewed from the left is, viewed in the direction of the array longitudinal axes 54a and 54b, for example in the middle between the sixth and seventh reception array element 52 on the first array longitudinal axis 54a, i.e offset to these, each arranged at a base distance of 40.
• the radar system 12 with the antenna array 22 according to the second exemplary embodiment is operated analogously to the radar system 12 with the antenna array 22 according to the first exemplary embodiment.
• FIG. 12 shows a range-direction diagram 60c for the radar system 12 in the range operating mode with dashed lines and a range-direction diagram 60d for the radar system 12 in the directional operating mode with a solid line.
• the respective ranges are recorded via azimuth cp.
• the radar system 12 has a maximum detection range of approximately 250 m in the range operating mode. In the directional operating mode, however, the radar system 12 only has a maximum detection range of slightly less than 200 m. In contrast, the radar system 12 has a larger field of view in the direction of azimuth cp in the directional operating mode than in the range operating mode.
• FIG. 13 shows an example of a received signal direction diagram 62d in a direction measurement sequence in which a target object was detected at an azimuth cp of 0° in front of motor vehicle 10.
• the sidelobe level is at about 11.2 dB. This is sufficient to resolve target objects with different reflectivities, for example in realistic driving situations with motor vehicle 10, with regard to their direction, namely the respective azimuth cp.
• Figure 14 shows an example of a family of curves of received signal direction diagrams 62e of several direction measurement sequences, in which two target objects, which have the same distance r and the same speed relative to the radar system 12, are at an angular distance of about 15 were detected by an azimuth cp of 0° in front of motor vehicle 10.
• the family of curves corresponds to direction measurement sequences in which radar signals 30 with different phase differences are transmitted.
• the two targets can be distinguished for all possible phase differences.
• the curves of the family of received signal direction diagrams 62b can be determined, for example, using a so-called beamforming approach and/or so-called super-resolution methods or the like.
• a received signal direction diagram 62f in a range measurement sequence corresponding to the situation from FIG. 14 is shown in FIG.
• the width of the main lobe is about 16°.
• the sidelobe level is at about 5.25dB, which is insufficient to resolve the two targets in the long range mode of operation.

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• Engineering & Computer Science (AREA)
• Radar, Positioning & Navigation (AREA)
• Remote Sensing (AREA)
• Physics & Mathematics (AREA)
• Computer Networks & Wireless Communication (AREA)
• General Physics & Mathematics (AREA)
• Computer Security & Cryptography (AREA)
• Electromagnetism (AREA)
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• 2020
  • 2020-07-29 DE DE102020119936.8A patent/DE102020119936A1/de active Pending
• 2021
  • 2021-07-27 EP EP21749603.3A patent/EP4189777A2/de active Pending
  • 2021-07-27 KR KR1020237007183A patent/KR20230043991A/ko unknown
  • 2021-07-27 CN CN202180064798.4A patent/CN116195139A/zh active Pending
  • 2021-07-27 JP JP2023506070A patent/JP2023535509A/ja active Pending
  • 2021-07-27 WO PCT/EP2021/070911 patent/WO2022023297A2/de active Application Filing

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