Radar device

Abstract

To provide a radar device capable of reducing a correction table size.SOLUTION: A radar device comprises: multiple single-body radar units 10, 20 for composing a cooperating radar; an array correction section for correcting values regarding a transmission antenna array and a reception antenna array of the cooperating radar by using a correction matrix; and an azimuth estimation section for estimating an azimuth of a target on the basis of the corrected values and a reception signal of the cooperating radar. The reception signal of the cooperating radar includes a reception signal of a virtual radar unit composed of the multiple single-body radar units 10, 20, and the array correction section corrects values regarding the transmission antenna array and the reception antenna array of the virtual radar unit by using a combination of correction matrices corresponding to the multiple single-body radar units 10, 20.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a radar device. [Background technology]

[0002] Vehicles use radar devices that estimate the azimuth of a target by transmitting and receiving electromagnetic waves. When such a radar device is installed behind the vehicle's bumper, the refraction and reflection of electromagnetic waves by the bumper causes an azimuth-dependent error in the characteristics of the antenna array, resulting in a decrease in the accuracy of azimuth estimation. This azimuth-dependent error varies depending on the relative position of the radar device with respect to the bumper, specifically, the axial offset and distance between the radar device and the bumper. Therefore, it is necessary to correct the estimation results depending on the actual relative position of the radar device with respect to the bumper.

[0003] For example, in the radar device described in Patent Document 1, the relative position of the radar device with respect to the bumper is changed to measure data for a correction matrix, and a correction table is prepared that stores a correction matrix for each relative position.Then, a correction matrix is ​​selected from the correction table according to the actual relative position and correction is performed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-3334 Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, a cooperative radar technology is known that improves azimuth estimation performance by preparing multiple radar units of the same type that transmit and receive electromagnetic waves and arranging them in different locations, and processing the transmitted and received signals of each radar unit as a single virtual array signal.

[0006] In such a cooperative radar, if a correction matrix corresponding to the relative position patterns of the entire cooperative radar is used, the size of the correction table may increase significantly, putting a strain on memory. For example, consider a case where two radar units are mounted behind the bumper. In this case, if the correction table size of a single radar unit, that is, the number of patterns of the relative positions between each radar unit and the bumper, is N, then the correction table size will be N 2 This becomes:

[0007] In view of the above, an object of the present disclosure is to provide a radar device that can reduce the size of a correction table. [Means for solving the problem]

[0008] In order to achieve the above object, according to one aspect of the present disclosure, a radar device includes a plurality of standalone radar units (10, 20) constituting a cooperative radar, an array correction unit (55) that corrects values ​​related to a transmitting antenna array and a receiving antenna array of the cooperative radar using a correction matrix, and an orientation estimation unit (56) that estimates the orientation of a target based on the corrected values ​​and a received signal of the cooperative radar, wherein the received signal of the cooperative radar includes a received signal of a virtual radar unit (30, 40) constituted by the plurality of standalone radar units, and the array correction unit corrects the values ​​related to the transmitting antenna array and the receiving antenna array of the virtual radar unit using a combination of correction matrices corresponding to the plurality of standalone radar units.

[0009] In this way, by combining the correction matrices for the individual radar units to correct the values ​​related to the transmitting antenna array and the receiving antenna array of the virtual radar unit, a correction matrix dedicated to the virtual radar unit is not required, and therefore the size of the correction table can be reduced.

[0010] The reference symbols in parentheses attached to each component indicate an example of the correspondence between the component and the specific components described in the embodiments described below. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating a configuration of a radar device according to a first embodiment. [Figure 2] FIG. 2 is a diagram showing the arrangement of radar units. [Figure 3] FIG. 10 is a diagram showing the arrangement of virtual radar units. [Figure 4] FIG. 2 is a diagram illustrating a configuration of a control unit. [Figure 5] FIG. 10 is a diagram illustrating an example of a correction table. [Figure 6] 10 is a flowchart of a direction estimation process. [Figure 7] FIG. 10 is a diagram showing the configuration of a measurement system for determining a correction matrix. [Figure 8] 10 is a flowchart of a process for determining a correction matrix. [Figure 9] 10 is a flowchart of a process for selecting a correction matrix. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. In the following embodiments, identical or equivalent parts will be denoted by the same reference numerals.

[0013] (First embodiment) A first embodiment will be described. In this embodiment, an example will be described in which a radar device 1 of the present disclosure is applied to a target detection device that is mounted on a vehicle and detects various targets existing around the vehicle.

[0014] The radar device 1 is disposed, for example, inside a front part of the vehicle, and emits electromagnetic waves toward the front of the vehicle and receives electromagnetic waves reflected by a target ahead of the vehicle to determine the distance to the target, the relative speed with respect to the vehicle itself, the direction with respect to the vehicle itself, etc. In this embodiment, an example will be described in which the radar device 1 is disposed inside a bumper B described below so as not to be directly exposed to the outside, and is protected by the bumper B.

[0015] The radar device 1 employs the FMCW method as a signal modulation method. FMCW is an abbreviation for Frequency Modulated Continuous Wave. The radar device 1 operates at a radio wave frequency band corresponding to millimeter waves (e.g., 76.5 GHz). Note that the operating frequency of the radio waves transmitted and received by the radar device 1 is not limited to a frequency corresponding to millimeter waves, and may be a frequency other than millimeter waves.

[0016] 1, the radar device 1 includes a plurality of radar units. In this embodiment, the radar device 1 includes two radar units 10 and 20, but the radar device 1 may include three or more radar units. The radar device 1 also includes a control unit 50.

[0017] The radar unit 10 includes a transmitter 11 and a receiver 12. The transmitter 11 has an oscillator 111 and a modulator 112, generates a transmission signal St1, and transmits a transmission wave corresponding to the transmission signal St1 from a plurality of transmission antennas Tx1. The receiver 12 receives, using a plurality of reception antennas Rx1, reflected waves of the transmission wave that have passed through the bumper B and been reflected by a target. The receiver 12 processes the signal received by the reception antenna Rx1 in an MMIC 121 to convert it into a reception signal Sr1 of a desired form. MMIC is an abbreviation for Monolithic Microwave Integrated Circuit. The receiver 12 inputs the reception signal Sr1 to the control unit 50.

[0018] The radar unit 20 includes a transmitter 21 and a receiver 22. The transmitter 21 has an oscillator 211 and a modulator 212, generates a transmission signal St2, and transmits a transmission wave corresponding to the transmission signal St2 from a plurality of transmission antennas Tx2. The receiver 22 receives, using a plurality of reception antennas Rx2, reflected waves of the transmission wave that have passed through the bumper B and been reflected by a target. The receiver 22 processes the signal received by the reception antenna Rx2 using an MMIC 221 to convert it into a reception signal Sr2 of a desired form. The receiver 22 inputs the reception signal Sr2 to the control unit 50.

[0019] As described above, the radar device 1 of this embodiment is configured as a MIMO radar having a plurality of transmitting antennas and a plurality of receiving antennas. MIMO is an abbreviation for Multiple Input Multiple Output.

[0020] The radar units 10 and 20 constitute a cooperative radar. Specifically, the radar units 10 and 20 are arranged inside the bumper B at a predetermined distance and facing approximately the same direction, as shown in Fig. 2. The transmitting antennas Tx1 and Tx2 and the receiving antennas Rx1 and Rx2 are arranged in an array on the substrates 13 and 23 provided in the radar units 10 and 20, respectively, to form an antenna array.

[0021] The receiving antenna Rx1 of the radar unit 10 also receives a reflected wave that is a wave transmitted from the transmitting antenna Tx2 of the radar unit 20 and reflected by a target. The receiving antenna Rx2 of the radar unit 20 also receives a reflected wave that is a wave transmitted from the transmitting antenna Tx1 of the radar unit 10 and reflected by a target.

[0022] That is, as shown in FIG. 3, the radar device 1 includes two more radar units 30 and 40 between the radar units 10 and 20, and has a configuration equivalent to that in which the radar units 10 to 40 each perform transmission and reception independently.

[0023] In this way, the radar units 10 and 20 each operate as a standalone radar unit that transmits and receives radio waves independently, and also operate to form virtual radar units 30 and 40 by receiving reflected waves of each other's transmitted waves. The transmitted signals of the cooperative radar include the transmitted signals of the radar units 30 and 40, and the received signals of the cooperative radar include the received signals of the radar units 30 and 40. By performing azimuth estimation based on the received signals of such cooperative radar, it is possible to improve azimuth estimation performance.

[0024] The radar units 10 and 20 are configured to transmit signals of different frequencies. For example, the radar unit 10 transmits an up-chirp signal whose frequency monotonically increases over time, and the radar unit 20 transmits a down-chirp signal whose frequency monotonically decreases over time. By setting the frequencies of the transmission signals St1 and St2 in this manner, the transmission signals St1 and St2 can be distinguished from each other in the received signals Sr1 and Sr2.

[0025] The control unit 50 constitutes an electronic control unit in the radar device 1. The control unit 50 is an electronic control device mainly composed of a microcomputer equipped with a processor and a memory. The memory is, for example, a ROM, a RAM, etc. Various functions of the microcomputer are realized by the processor executing a program stored in a non-transitory physical storage medium.

[0026] As shown in FIG. 4, the control unit 50 includes an FFT processing unit 51, a peak extraction unit 52, a relative position calculation unit 53, a correction matrix storage unit 54, an array correction unit 55, and an orientation estimation unit 56.

[0027] The FFT processing unit 51 performs frequency analysis on the received signals Sr1 and Sr2 using FFT. FFT is an abbreviation for Fast Fourier Transform. The result of the frequency analysis by the FFT processing unit 51 is input to the peak extraction unit 52.

[0028] The peak extraction unit 52 finds frequency peaks of the received signals Sr1 and Sr2 from the results of frequency analysis of the received signals Sr1 and Sr2 performed by the FFT processing unit 51. The peak extraction results by the peak extraction unit 52 are input to the relative position calculation unit 53 and the direction estimation unit 56.

[0029] The relative position calculation unit 53 calculates the relative position D of the radar units 10, 20 with respect to the bumper B from the frequency peaks obtained by the peak extraction unit 52. The relative position D indicates the positional deviation of the radar units 10, 20 with respect to the designed mounting positions, and is calculated for each of the radar units 10, 20. The relative position D is expressed as D = (α, β, d), where α is the horizontal axial deviation of the radar units 10, 20 with respect to the designed mounting positions, β is the vertical axial deviation, and d is the distance from the bumper B. The relative position D calculated by the relative position calculation unit 53 is input to the correction matrix storage unit 54.

[0030] The correction matrix storage unit 54 stores a correction matrix for correcting values ​​related to the array arrangement of the transmitting antennas Tx1 and Tx2 and the receiving antennas Rx1 and Rx2. In this embodiment, the correction matrix is ​​used to correct the array mode vectors of the transmitting antennas Tx1 and Tx2 and the receiving antennas Rx1 and Rx2. Each element of the correction matrix is ​​set according to the relative position D.

[0031] The array mode vector indicates the phase corresponding to the angle of arrival of the reflected wave, and is determined by the arrangement of the transmitting antennas Tx1 and Tx2 and the receiving antennas Rx1 and Rx2. The array mode vectors of the transmitting antennas Tx1 and Tx2 are expressed as a t1 (θ), a t2 (θ), and the array mode vectors of the receiving antennas Rx1 and Rx2 are a r1 (θ), a r2 (θ), where θ is the azimuth of the target.

[0032] A plurality of correction matrices are set according to the horizontal axis shift α, the vertical axis shift β, and the distance d. For example, assume that three correction matrices (α1, α2, α3) are set for the horizontal axis shift α, three correction matrices (β1, β2, β3) for the vertical axis shift β, and three correction matrices (d1, d2, d3) for the distance d. In this case, a correction table such as that shown in FIG. 5 is stored in the correction matrix storage unit 54. Each cell of the correction table stores a correction matrix corresponding to the relative position D. For example, the cell surrounded by the dashed line in FIG. 5 stores a correction matrix corresponding to α=α1, β=β3, and d=d1.

[0033] Array mode vector a t1 (θ), a t2 (θ), a r1 (θ), a r2 The correction matrix for correcting (θ) is Q t1 , Q t2 , Q r1 , Q r2 The correction matrix storage unit 54 stores the correction matrix Q corresponding to the relative position of the radar unit 10. t1 , Q r1 and a correction matrix Q corresponding to the relative position of the radar unit 20. t2 , Q r2 is selected from the correction table and input to the array correction unit 55.

[0034] If the correction matrices corresponding to the relative positions D are different between the radar units 10 and 20, correction tables are prepared individually for the radar units 10 and 20. On the other hand, if the correction matrices corresponding to the relative positions D are the same between the radar units 10 and 20, the radar units 10 and 20 may share one correction table. That is, the correction matrix Q is obtained from one correction table stored in the correction matrix storage unit 54. t1 , Q t2 , Q r1 , Q r2Alternatively, if the radar device 1 includes three or more radar units, two or more radar units may share a correction table. By having multiple radar units share a correction table, the storage capacity required for the correction matrix storage unit 54 can be reduced.

[0035] In addition, the direction estimation error may change depending on the direction of arrival of the reflected wave, i.e., the direction θ of the target. In this case, the correction matrix Q t1 , Q t2 , Q r1 , Q r2 depends on the orientation θ, Q t1 (θ), Q t2 (θ), Q r1 (θ), Q r2 (θ) is set in the form of Q in Equation 5. t1 , Q t2 , Q r1 , Q r2 Q t1 (θ), Q t2 (θ), Q r1 (θ), Q r2 (θ) and the peak value is detected.

[0036] The array correction unit 55 corrects the array mode vector using the correction matrix stored in the correction matrix storage unit 54. Specifically, the array correction unit 55 obtains the corrected array mode vector b(θ) using Equation 1. 11 (θ), b 22 (θ), b 12 (θ), b 21 (θ) is the array mode vector of the radar units 10 to 40 after correction.

[0037]

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[0038]

number

[0039] In this embodiment, the array mode vector a of the virtual radar unit 30 is 12 Correction matrix Q to correct (θ) 12 is the array mode vector a of radar units 10 and 20. 11 (θ), a 22 Correction matrix Q to correct (θ) t1 , Q r2 The array mode vector a of the virtual radar unit 40 is 21 Correction matrix Q to correct (θ) 21 is the array mode vector a of radar units 10 and 20. 11 (θ), a 22 Correction matrix Q to correct (θ) r1 , Q t2 It is composed of:

[0040] In this way, the array corrector 55 corrects the array mode vectors of the radar units 30 and 40 by combining the correction matrices corresponding to the radar units 10 and 20. The array corrector 55 inputs the correction results of the array mode vectors to the azimuth estimator 56.

[0041] The direction estimation unit 56 estimates the direction of the target that reflected the transmission wave from the radar units 10 and 20 relative to the vehicle, based on the array mode vector corrected by the array correction unit 55 and the received signals Sr1 and Sr2.

[0042] Equation 3 is a correction MUSIC equation when the radar units 10 and 20 are operated independently. MUSIC stands for Multiple Signal Classification. "H" in Equation 3 is the Hermitian transpose. Also, U N is the noise subspace, and the noise eigenvectors obtained by eigenvalue decomposition of the correlation matrix of the received signal are e1, e2, . . . e k Then, U N ={e1, e2, , e k}.

[0043]

number

[0044]

number

[0045]

number

[0046] The target detection process by the radar device 1 will be described with reference to Fig. 6. The process shown in Fig. 6 is executed periodically or irregularly while the radar device 1 is in operation.

[0047] When the transmitting antennas Tx1 and Tx2 transmit radio waves and the receiving antennas Rx1 and Rx2 receive reflected waves from targets, the control unit 50 acquires the received signals Sr1 and Sr2 from the receiving units 12 and 22 in step S11.

[0048] In the next step S12, the FFT processing unit 51 performs FFT processing. The control unit 50 performs frequency analysis of the received signals Sr1 and Sr2 using FFT to determine the distance to the target. The control unit 50 also performs FFT on each beat frequency component to determine the Doppler frequency and calculates the relative velocity of the target based on the Doppler frequency.

[0049] In the next step S13, the peak extraction unit 52 performs FFT peak processing. The peak extraction unit 52 detects, for example, a frequency bin at which a peak occurs in an RV map formed from the distance and velocity obtained by the FFT processing.

[0050] In the following step S14, the array correction unit 55 corrects the array mode vector using the correction matrix read from the correction matrix storage unit 54, as described above. In the following step S15, the direction estimation unit 56 performs direction estimation processing using the corrected array mode vector and the received signals Sr1 and Sr2, as described above. After step S15, the processing ends.

[0051] A method for determining the correction matrix will be described with reference to Figs. 7 and 8. In a measurement system for determining the correction matrix, for example, as shown in Fig. 7, a calibration device 60, a rotator 70 that rotates the calibration device 60, and a reference device 80 that serves as a target are used. The calibration device 60 is a device that has the same functions as the radar units 10 and 20 of the radar device 1. As the reference device 80, for example, a corner reflector having a predetermined RCS is used. RCS is an abbreviation for Radar Cross Section.

[0052] The correction matrix is ​​set based on the data acquired by the process shown in Fig. 8. First, in step S21, the relative position D of the calibration device 60 is set to D min and set the azimuth θ of the reference device 80 to the minimum azimuth θ min Set to.

[0053] D min =(α min , β min , d min ) and α min , β min , d min is the minimum value of α, β, and d in the range of the expected positional deviation. Also, the maximum value of α, β, and d in the range of the expected positional deviation is α max , β max , d max For example, if the design value of the distance d when attaching the radar unit 10 to the bumper B is 15 mm, and there is a possibility that the distance d may deviate within a range of 10 mm to 20 mm due to factors such as manufacturing errors, the minimum distance d min is 10 mm, and the maximum distance d max is 20mm.

[0054] Minimum orientation θ min , and the maximum orientation θ max is set according to the viewing angle of the radar units 10 and 20. For example, when the viewing angle of the radar units 10 and 20 is −70° to +70°, the minimum angle θ min is -70°, and the maximum azimuth θ max is 70°.

[0055] In the next step S22, calibration device 60 is placed at relative position D. In the next step S23, reference device 80 is placed at azimuth θ. In the next step S24, calibration device 60 transmits radio waves, and the received power when the reflected waves from reference device 80 are received is measured.

[0056] In the next step S25, the orientation θ of the reference device 80 reaches the maximum orientation θ max Determine whether θ is greater than or equal to θ. max If it is determined that this is not the case, the process proceeds to step S26. In step S26, Δθ is added to the azimuth θ of the reference device. Δθ is set to 1°, for example. After step S26, the process proceeds to step S23. If it is determined that θ≧θ in step S25, the process proceeds to step S23. max If it is determined that this is the case, the process proceeds to step S27.

[0057] In step S27, D max =(α max , β max , d max ) and the process up to step S26 is D min ~D max It is determined whether the process has been performed for all relative positions D selected within the range of α ≥ α max and β ≥ β max and d≧d max Determine whether α<α max or β<β max or d <d max If it is determined that the relative position D is equal to or greater than the predetermined value, the process proceeds to step S28. In step S28, ΔD is added to the relative position D. ΔD is calculated by adding α min ~α max , β min ~β max , d min ~d max The values ​​are changed appropriately so that the process of step S24 is performed for all combinations of α, β, and d selected within the range.

[0058] After step S28, the process proceeds to step S22. max and β ≥ β maxand d≧d max If it is determined that this is the case, the process ends.

[0059] In this way, the received power is measured while changing the relative position D and the direction θ. Then, based on the relationship between the relative position D, the direction θ, and the received power, a correction matrix is ​​determined so that the direction θ can be estimated accurately according to the relative position D.

[0060] There are various methods for calculating a correction matrix. For example, there is a method for calculating a correction matrix using a received signal Smeans received from a known arrival angle, or a signal subspace obtained by eigenvalue decomposition of the received signal Smeans, and an ideal mode vector determined by the known arrival angle. Another method for calculating a correction matrix is ​​using a noise subspace obtained by eigenvalue decomposition of a received signal Smeans received from a known arrival angle, and an ideal mode vector determined by the known arrival angle. Note that the received signal Smeans is obtained by averaging the actual received signal over a predetermined number of snapshots.

[0061] The correction matrix determined in this manner is stored in a correction table and stored in the correction matrix storage unit 54. After the radar device 1 is mounted on the vehicle and before the vehicle is shipped, the process shown in FIG. 9 is performed to select a correction matrix to be used in the array correction process depending on the relative positions of the radar units 10 and 20 with respect to the bumper B. The process shown in FIG. 9 is performed with a reference device placed outside the vehicle. Here, the case of selecting a correction matrix for the radar unit 10 will be described, but a correction matrix is ​​similarly selected for the radar unit 20.

[0062] First, in step S31, the radar device 1 calculates the relative position D of the radar unit 10. Specifically, the radar unit 10 transmits radio waves and receives reflected waves from the reference device, and the FFT processing unit 51 and peak extraction unit 52 perform FFT processing and FFT peak extraction processing on the received signal Sr1, similar to steps S12 and S13 in FIG. 6. The relative position calculation unit 53 then calculates the relative position D of the radar unit 10 based on the FFT peaks. For example, the memory of the control unit 50 stores the measurement results from step S24 in FIG. 8, and the relative position calculation unit 53 compares the stored measurement results with the received signal Sr1 to obtain the relative position D when they most closely match.

[0063] In the following step S32, the relative position calculation unit 53 inputs the relative position D calculated in step S31 to the correction matrix storage unit 54. In the following step S33, the correction matrix storage unit 54 calculates a correction matrix Q from the correction table in accordance with the relative position D input in step S32. t1 , Q r1 is selected and input to the array correction unit 55. After step S33, the processing ends. The array correction unit 55 uses the correction matrix input in step S33 to perform the array correction processing in step S14.

[0064] The effects of this embodiment will be described. Assume that a correction table is prepared according to the axis shift of the entire cooperative radar including the radar units 10 and 20 and the virtual radar units 30 and 40, and the distance from the bumper B. In this case, if the number of transmitting antennas Tx1 and Tx2 is Nt and the number of receiving antennas Rx1 and Rx2 is Nr, the virtual array size of the cooperative radar is 4NtNr. Therefore, the correction matrix size by the virtual array is 16Nt 2 Nr 2 This becomes:

[0065] On the other hand, in this embodiment, correction matrices for the two radar units 10 and 20 are prepared, and the array mode vectors of the virtual radar units 30 and 40 are corrected using a combination of the correction matrices for the radar units 10 and 20. Therefore, correction matrices dedicated to the radar units 30 and 40 are not required, and the total size of the required correction matrices is 2(Nt 2 +Nr 2 )

[0066] F=16Nt 2 Nr 2 -2(Nt 2 +Nr 2 ), then F=2Nt 2 Nr 2 {8-(1 / Nr 2 +1 / Nt 2 )}. Here, since Nt ≥ 1 and Nr ≥ 1, Nt 2 Nr 2 ≧1. Also, 8-(1 / Nr 2 +1 / Nt 2 ) is smallest when Nt=Nr=1. In this case, 8-(1 / Nr 2 +1 / Nt 2 )=6, so F>0. Therefore, the total correction matrix size of the radar units 10 and 20 is smaller than the correction matrix size of the entire cooperative radar including the virtual radar unit.

[0067] As described above, in this embodiment, the array mode vectors of the radar units 30 and 40, which are virtual radar units, are corrected by combining the correction matrices for the radar units 10 and 20. This eliminates the need for dedicated correction matrices for the radar units 30 and 40, thereby reducing the size of the correction table. Furthermore, the size of the correction matrices in the correction table can be reduced. Furthermore, an increase in the measurement time for data for generating the correction matrix can be suppressed.

[0068] (Other embodiments) The present disclosure is not limited to the above-described embodiments and can be modified as appropriate. It goes without saying that the elements constituting the embodiments are not necessarily essential unless they are specifically stated as essential or are clearly considered essential in principle. Furthermore, when numerical values ​​such as the number, value, amount, and range of the elements of the embodiments are mentioned in the above-described embodiments, they are not limited to the specific number unless they are specifically stated as essential or are clearly limited to a specific number in principle.

[0069] The controller and methods described herein may be implemented by a special-purpose computer configured with a processor and memory programmed to perform one or more functions embodied in a computer program. Alternatively, the controller and methods described herein may be implemented by a special-purpose computer configured with a processor configured with one or more dedicated hardware logic circuits. Alternatively, the controller and methods described herein may be implemented by one or more special-purpose computers configured with a processor and memory programmed to perform one or more functions in combination with a processor configured with one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by a computer on a computer-readable non-transitory storage medium. [Explanation of symbols]

[0070] 10 Radar Unit 20 Radar Unit 30 Radar Unit 40 Radar Unit 55 Array correction unit 56 Direction estimation part

Claims

1. A radar device, a plurality of individual radar units (10, 20) constituting a cooperative radar; an array correction unit (55) that corrects values ​​related to the transmitting antenna array and the receiving antenna array of the cooperative radar using a correction matrix; an azimuth estimation unit (56) that estimates the azimuth of a target based on the corrected value and the received signal of the cooperative radar, The received signals of the cooperative radar include received signals of a virtual radar unit (30, 40) configured by a plurality of the single radar units, The array correction unit corrects values ​​related to the transmitting antenna array and the receiving antenna array of the virtual radar unit by using a combination of the correction matrices corresponding to the plurality of single radar units.

2. The single radar unit is disposed inside a bumper (B) of a vehicle, The radar device according to claim 1 , wherein the correction matrix is ​​set in accordance with a relative position of the standalone radar unit with respect to the bumper.

3. 3. The radar device according to claim 1, wherein the array correction unit corrects an array mode vector determined by the arrangement of transmitting antennas (Tx1, Tx2) and receiving antennas (Rx1, Rx2) included in the standalone radar unit.

4. a correction matrix storage unit (54) for storing a correction table in which the correction matrix is ​​stored; 3. The radar device according to claim 1, wherein at least two of the plurality of single radar units share the correction table.

5. The radar device according to claim 1 or 2, wherein the correction matrix is ​​set depending on the direction.

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