Vehicle radar device and control method thereof

Abstract

An embodiment of the present disclosure relates to a radar device, which includes: an antenna unit, including a transmitting antenna for transmitting a transmission signal and a receiving antenna for receiving a reception signal reflected from a target; a signal processor, configured to determine target direction information by using a phase difference between reception signals received from respective reception antennas; and a controller, configured to control to respectively execute a first mode and a second mode of transmitting and receiving signals at different pulse repetition intervals.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Korean Patent Application No. 10-2021-0022244, filed on February 19, 2021, which is hereby incorporated by reference for all purposes as if fully set forth herein. Technical Field

[0003] Embodiments of the present disclosure relate to a vehicle radar device and a control method thereof, and more particularly, to a vehicle radar device and a control method thereof for determining a direction of a target by using a phase difference between received signals. Background Art

[0004] Radar refers to a device that uses radio waves to observe targets. Radar can send signals from the transmitting antenna and receive and analyze the signals reflected by the target at the receiving antenna to detect the direction, distance, speed, etc. of the target.

[0005] In particular, unlike in the military or meteorological fields, in the case of vehicle radars, it is necessary to optimize performance while using a miniaturized device. In this regard, recently, radar devices equipped with multiple-input multiple-output (MIMO) antennas have been used.

[0006] Meanwhile, in the case of transmitting signals using two or more transmission antennas in such a radar device, there is a problem that the accuracy of measuring the direction of a target may deteriorate depending on the time difference between the transmission antennas or the setting of a pulse repetition interval. Summary of the invention

[0007] Embodiments of the present disclosure provide a vehicle radar device capable of improving the accuracy of measuring the direction of a target and a control method thereof.

[0008] In addition, embodiments of the present disclosure provide a vehicle radar device capable of solving a direction measurement error by correcting a phase measurement error of a received signal and a control method thereof.

[0009] In one aspect of the present disclosure, the present embodiment may provide a vehicle radar device, which includes: an antenna unit, including a transmitting antenna for sending a transmit signal and a receiving antenna for receiving a receive signal reflected from a target; a signal processor, configured to determine target direction information by using a phase difference between receive signals received from each receive antenna; and a controller, configured to control to respectively execute a first mode and a second mode of sending and receiving signals at different pulse repetition intervals, wherein the signal processor is configured to correct a second mode receive signal received in a second mode based on a first mode receive signal received in a first mode when a preset phase correction condition is met.

[0010] In another aspect of the present disclosure, the present embodiment may provide a control method for a vehicle radar device, the control method comprising: sending a transmit signal using a transmitting antenna and receiving a receive signal reflected from a target using a receiving antenna; determining target direction information by using a phase difference between receive signals received from each receive antenna; and controlling to respectively execute a first mode and a second mode for sending and receiving signals at different pulse repetition intervals, wherein determining the target direction information comprises correcting a second mode receive signal received in a second mode based on a first mode receive signal received in a first mode when a preset phase correction condition is met.

[0011] According to an embodiment of the present disclosure, a vehicle radar device and a control method thereof capable of improving the accuracy of measuring the direction of a target may be provided.

[0012] In addition, according to an embodiment of the present disclosure, a vehicle radar device capable of solving a direction measurement error by correcting a phase measurement error of a received signal and a control method thereof can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a block diagram of a vehicle radar device according to the present disclosure.

[0014] Figure 2 An example of a configuration for detecting a target using a vehicle radar device according to an embodiment is shown.

[0015] Figure 3 is a diagram for exemplarily explaining a configuration in which a transmission antenna is used in a time-division manner in a vehicle radar device according to an embodiment.

[0016] Figure 4 is a diagram for exemplarily explaining a phase difference generated in a received signal according to an embodiment.

[0017] Figure 5 is a diagram for explaining a configuration in which a first mode and a second mode are performed within one frame according to an embodiment.

[0018] Figure 6 is a diagram for explaining a configuration performed by differently setting a pulse repetition interval in a first mode and a second mode according to an exemplary embodiment.

[0019] Figure 7 An example of a configuration for detecting targets having different speeds using a vehicle radar device according to an embodiment is shown.

[0020] Figure 8 is a diagram for explaining a configuration for detecting targets having different speeds in a second mode according to an embodiment.

[0021] Fig. 9 is a diagram for explaining a configuration for performing phase correction in a first mode and a second mode according to an exemplary embodiment.

[0022] Fig.10 is a diagram for explaining a configuration for performing phase correction in a first mode and a second mode according to another embodiment.

[0023] Fig.11 is a diagram for explaining states before and after phase correction according to an exemplary embodiment.

[0024] Fig.12 is a flowchart illustrating a control method of a vehicle radar device according to the present disclosure.

[0025] Fig.13 is a flow chart of signal processing steps according to an embodiment. DETAILED DESCRIPTION

[0026] In the following description of examples or embodiments of the present disclosure, reference will be made to the accompanying drawings, in which specific examples or embodiments that can be implemented are shown by way of illustration, and in the accompanying drawings, the same reference numerals and symbols may be used to represent the same or similar components, even if the same reference numerals and symbols are shown in different drawings from each other. In addition, in the following description of examples or embodiments of the present disclosure, when it is determined that a detailed description of the well-known functions and components incorporated herein may make the subject matter in some embodiments of the present disclosure unclear, the description will be omitted. Terms such as "including", "having", "comprising", "constituting", "comprising", and "formed with" used herein are generally intended to allow the addition of other components unless these terms are used with the term "only". As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise.

[0027] Terms such as "first", "second", "A", "B", "(A)" or "(B)" may be used herein to describe elements of the present disclosure. Each of these terms is not used to limit the nature, sequence, order or quantity of the elements, etc., but is only used to distinguish the corresponding element from other elements.

[0028] When it is mentioned that a first element is “connected or coupled”, “contacted or overlapped”, etc. with a second element, it should be interpreted that not only the first element can be “directly connected or coupled” or “directly contacted or overlapped” with the second element, but also a third element can be “interposed” between the first element and the second element, or the first element and the second element can be “connected or coupled”, “contacted or overlapped”, etc. with each other through a fourth element. Here, the second element may be included in at least one of the two or more elements that are “connected or coupled”, “contacted or overlapped”, etc. with each other.

[0029] When time-related terms such as "after", "after", "next", "before" and the like are used to describe a process or operation of an element or configuration, or a flow or step in an operation, process, or manufacturing method, these terms may be used to describe non-sequential or non-sequential processes or operations unless used with the terms "directly" or "immediately".

[0030] In addition, when referring to any dimension, relative size, etc., the numerical value or corresponding information (e.g., level, range, etc.) of the element or feature should be considered to include tolerances or error ranges that may be caused by various factors (e.g., process factors, internal or external influences, noise, etc.), even if the relevant description is not detailed. In addition, the term "may" fully includes all meanings of the term "can".

[0031] In the present disclosure, the first mode is defined as having the same meaning as the pre-acquisition mode, the pre-mode or the calibration mode. In addition, the second mode is defined as having the same meaning as the normal mode or the general mode.

[0032] Figure 1 is a block diagram of a vehicle radar device according to the present disclosure.

[0033] Reference Figure 1 , the vehicle radar device 100 according to the present disclosure may include an antenna unit 110, a signal processor 120, and a controller 130. In addition, the antenna unit 110, the signal processor 120, and the controller 130 may be connected to each other.

[0034] As an example, the vehicle radar device 100 may include: an antenna unit 110, including a transmitting antenna for transmitting a transmitting signal and a receiving antenna for receiving a receiving signal reflected from a target; and at least one of a signal processor 120 and a controller 130, the signal processor 120 determines the direction of the target by using a phase difference between the receiving signals received from each receiving antenna, and the controller 130 controls so that a first mode and a second mode of sending and receiving signals at different pulse repetition intervals are respectively executed.

[0035] The antenna unit 110 may include at least two or more transmission antennas and reception antennas, respectively. In addition, in some cases, all antennas included in the antenna unit 110 may be used, or only some antennas may be used.

[0036] In the antenna unit 110, a multiple input multiple output (MIMO) technology using two or more transmission antennas and reception antennas, respectively, may be used. In addition, in some cases, a single input multiple output (SIMO) technology, a multiple input single output (MISO) technology, or a single input single output (SISO) technology may be used. That is, it may be set to use all antennas included in the antenna unit 110, or it may be set to use only a part of each of the transmission antenna and the reception antenna.

[0037] The transmitting antenna can transmit a signal by radiating an electromagnetic signal. In this case, the transmission signal can be transmitted based on preset values ​​of the transmission direction and range of the signal, the transmission time, the strength of the signal, etc. In addition, the waveform of the transmission signal can be implemented as one or more of various known waveforms such as a pulse waveform and a chirp waveform.

[0038] The receiving antenna can receive a signal incident from the outside. Here, the received signal may include a signal that the transmission signal sent from the transmitting antenna is reflected by the target. In addition, the received signal may contain information about the strength and amplitude of the signal, the frequency, the angle of arrival, the distance from the target, and the speed of the target.

[0039] In addition, the transmission signal and the reception signal can be implemented as using a transmission channel and a reception channel respectively, or can be implemented as using a composite channel. Here, the composite channel can be implemented as a change in the amplitude and phase of the reception signal with respect to the transmission signal and its reflected signal. In addition, the transmission signal and the reception signal can be synthesized and processed, and the synthesized signal can include an intermediate frequency (IF) signal.

[0040] For example, in a configuration including two transmitting antennas including a first transmitting antenna Tx1 and a second transmitting antenna Tx2 and four receiving antennas including a first receiving antenna Rx1, a second receiving antenna Rx2, a third receiving antenna Rx3 and a fourth receiving antenna Rx4, if a signal is transmitted from Tx1 and a reflected signal is received from Rx4, the signal can be processed in a synthetic channel of Tx1-Rx4.

[0041] Meanwhile, signals transmitted and received by the antenna unit 110 may be controlled by the controller 130. In this case, signal transmission / reception control may be performed based on preset setting values ​​required for signal transmission / reception, such as the number of transmission antennas and reception antennas used respectively and the pulse repetition interval.

[0042] In this case, two or more modes having different setting values ​​may be set based on control setting values, respectively, and transmission and reception of a signal in each mode may be controlled based on the control setting value of each mode.

[0043] For example, signal transmission / reception can be controlled based on a control setting value, which is set to use a first transmitting antenna to transmit signals at a first pulse repetition interval in a first mode, and to use the first transmitting antenna and the second transmitting antenna to transmit signals at a second pulse repetition interval in a second mode.

[0044] Specific details regarding signal control in the antenna unit 110 in the controller 130 will be described in more detail below.

[0045] The signal processor 120 may determine phase information about the phase of each signal, target direction information about the direction of the target located from the radar, etc. based on the signal transmitted and received by each antenna. Here, the signal processor 120 may process the signals transmitted and received in different modes separately, or may process the signals transmitted and received in different modes together.

[0046] For example, if a signal is transmitted and received in each of the first mode and the second mode, the signal processor 120 may determine the phase difference information and the target direction information using only the first mode received signal or only the second mode received signal. Alternatively, the signal processor 120 may determine the phase difference information and the target direction information by using information of the first mode received signal and the second mode received signal together.

[0047] In addition, the signal processor 120 may determine phase difference information between reception signals received from each reception antenna, and may determine target direction information using the phase difference information.

[0048] The phase difference information may be determined by comparing phase information of each reception signal, or may be determined by using information included in two or more reception signals received from at least two reception antennas.

[0049] Specifically, the information included in the received signal may include the chirp time T c , the wavelength λ and frequency f of the received signal, the distance d and speed v of the target, and the Doppler frequency f of the received signal d Here, the speed of the target may include a relative speed of the target with respect to the vehicle radar device 100 .

[0050] For example, the phase difference information may be calculated based on at least one of the following equations, and in addition to the following equations, any known technique capable of calculating the phase difference may be used.

[0051] [Equation]

[0052] The phase difference ΔΦ between the received signals

[0053] = phase difference constant × target Doppler frequency × chirp time

[0054] = phase constant × target speed × chirp time × received signal frequency

[0055] = phase constant × target speed × chirp time ÷ wavelength of received signal

[0056] = phase constant × target distance ÷ wavelength of received signal

[0057] Here, the phase constant refers to a constant commonly required for calculating the phase difference. Such a phase constant may have a value such as 2π or 4π according to the specifications of the vehicle radar device 100 of the present disclosure or the target detection situation, and may be set differently if the specifications or the target detection situation change.

[0058] The target direction information can be calculated based on the arrival angle information of the received signal reflected back at the target. In addition, the arrival angle information can be calculated based on at least one of the following equations, and in addition to the following equations, any known technology capable of calculating the arrival angle of the received signal can be used.

[0059] [Equation]

[0060] Angle of arrival (θ)

[0061] =sin -1 {(wavelength of received signal × phase difference between received signals) / (2π × distance to target)}

[0062] =sin -1 {Phase difference between received signals / (2π×distance to target×frequency of received signal)}

[0063] =sin -1 {(wavelength of received signal × phase difference between received signals) / (2π × speed of target × chirp time)}

[0064] Meanwhile, if it is determined that a preset phase correction condition is satisfied, the signal processor 120 may correct the phase of the received signal. At least one of these phase correction conditions may be set, and if one of them is satisfied, phase correction may be performed.

[0065] This phase correction may be performed using at least one of a method of individually correcting phase information of received signals and a method of correcting phase difference information between received signals.

[0066] Specifically, if one or more of the various phase correction conditions are met, the phase of the received signal may be corrected by adding π to the phase of the received signal. In this case, phase correction may be performed on all or part of the measured received signal.

[0067] For example, if a reflected signal of a signal sent by a first transmitting antenna is received in a first mode, and a reflected signal of a signal sent by a first transmitting antenna and a second transmitting antenna is received in a second mode, phase correction can be performed only on a received signal obtained by receiving the reflected signal of a signal sent by the second transmitting antenna in the second mode.

[0068] As described above, since the target direction information can be determined based on the phase difference information between the received signals, the target direction information can be corrected by correcting the phase of the received signal. That is, the accuracy of target direction estimation can be improved by phase correction.

[0069] As an example, the phase correction condition may be set based on the phase difference information of the received signal. As a specific example, the phase correction condition may be a condition that determines that the phase difference information between the received signal received by reflection of the transmitted signal of the first transmitting antenna and the received signal received by reflection of the transmitted signal of the second transmitting antenna is π or greater. In addition, if the phase correction condition is satisfied, phase correction may be performed.

[0070] As another example, the phase correction condition may be set based on the Doppler frequency information and the maximum Doppler frequency information of the received signal. As a specific example, the phase correction condition may be set such that phase correction is performed when the Doppler frequency information of the first mode received signal exceeds the maximum Doppler frequency information of the second mode received signal.

[0071] Here, the Doppler frequency refers to a change in apparent frequency due to the Doppler effect. For example, in the vehicle radar device 100 according to the present disclosure, the Doppler frequency can be determined based on the frequency difference between a transmission signal transmitted from a transmission antenna and a reception signal reflected by a target.

[0072] In addition, the maximum Doppler frequency refers to the maximum value that the Doppler frequency can have when the frequency of the transmitted signal and the speed of the target have constant values. For example, if the conditions that the frequency of the transmitted signal remains constant and the speed of the detected target is constant are satisfied based on the control setting value preset for the first mode, then under normal circumstances, the Doppler frequency measured in the first mode will not exceed the maximum Doppler frequency of the first mode.

[0073] That is, in the case of performing signal transmission / reception based on a preset control setting value, the maximum Doppler frequency can be predetermined regardless of signal transmission / reception. In addition, if the measured Doppler frequency exceeds the maximum Doppler frequency, it is determined that a measurement error has occurred, in which case a phase correction condition for performing phase correction can be set.

[0074] In addition, in a state where two or more modes having different control setting values ​​are executed in the vehicular radar device 100 according to the present disclosure, determination of whether the phase correction condition is satisfied may be performed by comparing the setting value and the measurement value of each mode.

[0075] Generally, the smaller the pulse repetition interval in a radar, the greater the maximum detection speed, but the smaller the maximum detection range.

[0076] For example, in a case where the first mode transmits a signal at a first pulse repetition interval and the second mode transmits a signal at a second pulse repetition interval, the maximum detection speed and the maximum detection range may differ according to the difference in the pulse repetition interval in each mode.

[0077] That is, if the first pulse repetition interval is smaller than the second pulse repetition interval, the maximum detection speed of the first mode can be greater than the maximum detection speed of the second mode, and the maximum detection range of the first mode can be smaller than the maximum detection range of the second mode. In addition, received correction can be performed by using this characteristic.

[0078] As an example, if the speed of the target is less than the maximum detection speed of the first mode but exceeds the maximum detection speed of the second mode, a target measurement error may occur in the second mode. The situation where an object exceeding the maximum detection speed is detected at a speed different from the actual speed may be referred to as velocity folding or velocity aliasing.

[0079] In this case, the detection signal of the first mode can be used to correct the detection signal of the second mode. That is, the second mode reception signal can be corrected by using at least one of the speed information, distance information, Doppler frequency information and phase difference information of the target in the first mode reception signal.

[0080] As another example, if the distance of the target is less than the maximum detection range of the second mode but exceeds the maximum detection range of the first mode, this may result in target measurement errors in the first mode.

[0081] In this case, the detection signal of the first mode can be corrected using the detection signal of the second mode. That is, the first mode reception signal can be corrected by using at least one of the speed information, distance information, Doppler frequency information and phase difference information of the target in the second mode reception signal.

[0082] Will refer to below Figures 7 to 10 The correction of the received signal is described by taking a more specific example.

[0083] The controller 130 may control the transmission and reception of the signal based on a preset control setting value. Here, the control setting value may include at least one of the transmission / reception antenna specification, the transmission time of the signal, the frequency, the radiation direction and the intensity. Here, the transmission time of the signal may be set to a pulse repetition interval (PRI).

[0084] In addition, the controller 130 can set different control setting values ​​for at least two or more modes, so that the transmission and reception of signals can be performed based on the different control setting values ​​of each mode. In addition, according to the control setting value of each mode, part or all of the detection performance of the vehicle radar device 100 according to the present disclosure can be controlled to change.

[0085] For example, the controller may set the control setting value so that a signal is transmitted at a first pulse repetition interval using the first transmitting antenna in the first mode, and a signal is transmitted at a second pulse repetition interval using the first transmitting antenna and the second transmitting antenna in the second mode.

[0086] In this case, if the first mode using one transmission antenna and the second mode using two transmission antennas are compared, the resolution of the second mode may be evaluated to have better performance than the first mode.

[0087] As an example, the controller 130 may set the control setting values ​​of the first mode and the second mode so that the first pulse repetition interval is less than the second pulse repetition interval. In this case, the maximum detection speed of the first mode is greater than the maximum detection speed of the second mode, and the maximum detection range of the first mode is less than the maximum detection range of the second mode, so that the target detection performance of each mode can be different.

[0088] Meanwhile, the controller 130 may control the first mode and the second mode to be executed in units of time or frame, and may control the first mode and the second mode by presetting an execution time, an execution order, and the like.

[0089] For example, the controller 130 may control the first mode and the second mode to be performed within one frame. That is, if the vehicle radar device 100 according to the present disclosure performs one scan, the first mode and the second mode may be controlled to be performed within the scan range.

[0090] As described above, if the first mode and the second mode are controlled to be executed within a frame range, they will not become larger than a specific size at the measurement time point. Therefore, according to the present disclosure, when the measurement results of the position and speed of the target of each mode are compared and corrected with the measurement results of other modes, the accuracy of the target measurement can be improved.

[0091] In this case, the first mode and the second mode may be set to be executed simultaneously, or may be set to be executed separately from each other. Here, if the first mode and the second mode are executed separately from each other, a time division multiplexing (TDM) method of transmitting and receiving signals at different times may be used.

[0092] In addition, if the first mode and the second mode are controlled by time division multiplexing, it can be set to execute the first mode first and then the second mode.

[0093] For example, if the pulse repetition interval of the first mode is set small, even if the speed of the target exceeds the maximum detection speed of the second mode, the result of the first mode executed first can be used to correct the second mode reception signal, thereby improving the accuracy of the speed and angle of the target measurement.

[0094] As another example, if the pulse repetition interval of the first mode is set large, even if the distance of the target exceeds the maximum detection range of the second mode, the result of the first mode executed first can be used to correct the second mode received signal, thereby improving the accuracy of the speed and angle of the target measurement.

[0095] In addition, the controller 130 can control both the first mode and the second mode to be executed within one frame, and in this case, it can be controlled so that the first mode is executed first and then the second mode is executed. In addition, if the phase correction of the received signal is performed by the signal processor 120, the signal transmission / reception and control of each mode can be performed by reflecting the correction content thereafter.

[0096] Figure 2 An example of a configuration for detecting a target using a vehicle radar device according to an embodiment is shown.

[0097] Reference Figure 2 , the vehicle radar device 100 according to the embodiment can detect the target 210 using the transmitted / received signal. In this case, the target 210 is an object moving at a constant target speed 220 and can be detected as being located in a target direction 230.

[0098] The vehicle radar device 100 according to the embodiment can transmit a signal based on a preset pulse repetition interval, and can receive a signal returned by being reflected on a target. Then, the target can be detected by calculating the target speed 220 and the target direction 230 using information included in the transmitted signal and the received signal.

[0099] First, the vehicular radar device 100 according to the embodiment may calculate the phase difference ΔΦ between reception signals within one chirp, and may calculate the target speed 220 and the target direction 230 based on the calculated phase difference information.

[0100] Here, the phase difference information may be determined using at least one of a value obtained by multiplying Doppler frequency information included in the reception signal and the chirp time and a value obtained by dividing the distance of the target by the wavelength of the reception signal.

[0101] The target speed 220 may be determined using at least one of a value obtained by multiplying the previously calculated phase difference information by the wavelength of the received signal and then dividing by the chirp time, a value obtained by dividing the phase difference information by the frequency of the received signal and the chirp time, a value obtained by multiplying the wavelength of the received signal by the distance to the target, and a value obtained by multiplying the speed of light by the Doppler frequency of the target and dividing by the frequency of the received signal. In addition, any known technique capable of obtaining the speed of the target based on the radar signal may be used.

[0102] A method of determining the target direction 230 by estimating the arrival angle of the target may be used. In this case, a sinusoidal graph or an inverse function graph of a sinusoidal function may be used to determine the target direction. In the case of using a sinusoidal graph or an inverse function graph of a sinusoidal function, the target direction may be determined using at least one of previously calculated phase difference information, the wavelength and frequency of the received signal, the speed and distance of the target, and the chirp time. In addition, any known technique capable of obtaining the direction of the target based on the radar signal may be used.

[0103] Meanwhile, the phase difference information, the target speed 220, and the target direction 230 may be determined in at least two or more modes. Then, a configuration for comparing and correcting the respective determination results may be included.

[0104] Will refer to below Figures 7 to 10 The correction of such determination results will be described with a more specific example.

[0105] Figure 3 is a diagram for exemplarily explaining a configuration in which a transmission antenna is used in a time-division manner in a vehicle radar device according to an embodiment.

[0106] The vehicle radar device according to the embodiment can use two or more transmitting antennas to transmit a signal, and the transmitted signal can be represented by a time-frequency diagram. In addition, in some cases, when the transmitted signal corresponds to a chirp signal, the transmitted signal can be represented in the form of a chirp in the time-frequency diagram.

[0107] In this case, if Figure 3 As shown, each transmitting antenna can be used to transmit signals at different times in a time division multiplexing (TDM) manner.

[0108] Reference Figure 3, the vehicle radar device according to the embodiment can transmit signals in a time division multiplexing manner using two transmission antennas Tx1 and Tx2. In this case, in the time-frequency diagram, the transmission signal can be represented by chirps for each transmission antenna alternately represented.

[0109] For example, in Figure 3 In the figure shown, the solid line represents the chirp generated by Tx1, and the dotted line represents the chirp generated by Tx2. Here, the chirp time 310 refers to the time T corresponding to one chirp in each transmitting antenna. c In addition, the Tx1-Tx2 time difference 320 indicates a gap time T corresponding to a gap set in order to use Tx1 and Tx2 so that Tx1 and Tx2 do not overlap each other in time. g .

[0110] In this case, the chirp times of Tx1 and Tx2 may be set to the same time or to different times. In addition, each chirp time and Tx1-Tx2 time difference may be set to the same time or to different times.

[0111] Figure 4 is a diagram for exemplarily explaining a phase difference generated in a received signal according to an embodiment.

[0112] The vehicle radar device according to the embodiment can use two or more transmitting antennas Tx1 and Tx2 and four receiving antennas Rx1, Rx2, Rx3 and Rx4 to send and receive signals. The signals sent and received in this way can be represented by a synthesized channel-frequency diagram. In addition, in the case where such a signal corresponds to a chirp signal, such a signal can appear in the synthesized channel-frequency diagram in the form of a linear chirp.

[0113] Reference Figure 4 , the vehicle radar apparatus according to the embodiment may transmit and receive signals in a time division manner using two transmitting antennas Tx1 and Tx2 and four receiving antennas Rx1 , Rx2 , Rx3 , and Rx4 .

[0114] Generally, the resolution of a radar can be improved as the number of antennas used increases. For example, in the case of a radar device that measures a target using a phase difference between receiving antennas, the resolution can be further improved when there are eight receiving antennas compared to when there are four receiving antennas. However, a method of simply arranging more receiving antennas may have spatial and temporal limitations.

[0115] In this regard, when two or more transmitting antennas are used in a radar having the same number of receiving antennas, a phase difference equal to the number of transmitting antennas×the number of receiving antennas can be used, so that the resolution can be further improved.

[0116] For example, a radar using one transmitting antenna and four receiving antennas can use four phase differences of 1×4=4. In addition, a radar using one transmitting antenna and eight receiving antennas can use eight phase differences of 1×8=8, and a radar using two transmitting antennas and four receiving antennas can also use eight phase differences of 2×4=8.

[0117] Therefore, a configuration using one transmit antenna and eight receive antennas can utilize eight phase differences using 1+8=9 antennas, and a configuration using two transmit antennas and four receive antennas can utilize eight phase differences using 2+4=6 antennas. Therefore, since the latter configuration can be a radar system that utilizes the same number of phase differences using a smaller number of antennas, the efficiency of the antenna configuration can be improved accordingly.

[0118] However, in the case of a configuration using two or more transmitting antennas, when calculating the phase difference between the receiving antennas, not only the time difference between the receiving antennas but also the time difference between the transmitting antennas may occur, resulting in unnecessary phase jumps.

[0119] For example, Figure 4 As shown, in addition to the phase difference 410 between Rx1 and Rx2, the phase difference 420 between Rx2 and Rx3, the phase difference 430 between Rx3 and Rx4, and the phase difference 440 between Rx4 and Rx1, there will be a phase difference 450 between Tx1-Rx4 and Tx2-Rx1, that is, a phase jump between Tx1 and Tx2.

[0120] Therefore, the configuration using two transmitting antennas and four receiving antennas may result in an undesirable phase jump compared to the configuration using one transmitting antenna and eight receiving antennas, even though the number of phase differences between the receiving antennas is respectively equal to 8. In addition, such a phase jump may result in undesirable errors in the measurement of the direction, distance, and speed of the target.

[0121] In addition, in this case, the phase jump between the transmitting antennas Tx1 and Tx2 can be exemplarily represented by the following equation 1.

[0122] [Equation 1]

[0123]

[0124] Here, c is the speed of light, T c is the chirp time, f is the frequency of the received signal, and f d is the Doppler frequency.

[0125] Figure 5 is a diagram for explaining a configuration in which a first mode and a second mode are performed within one frame according to an embodiment.

[0126] Reference Figure 5 , the vehicle radar device according to the embodiment can perform the first mode 520 and the second mode 530 in a time division (multiplexing) manner within one frame 510. That is, when one frame 510 is the total time in the time-frequency diagram, the first mode 520 and the second mode 530 can be separated in time.

[0127] In addition, the first mode may utilize a single-input multiple-output (SIMO) scheme using one transmit antenna and multiple receive antennas, and the second mode may utilize a multiple-input multiple-output (MIMO) scheme using two transmit antennas and multiple receive antennas. Here, in the second mode, signals may also be processed in a time-division manner between Tx1 and Tx2.

[0128] exist Figure 5 In the diagram shown, the solid line indicates the chirp generated by Tx1, and the dotted line indicates the chirp generated by Tx2. That is, in the first mode based on SIMO, there is only the chirp generated by Tx1 (solid line), and in the second mode based on MIMO, there are both the chirps generated by Tx1 and Tx2 (solid line and dotted line).

[0129] Figure 6 is a diagram for explaining a configuration performed by differently setting a pulse repetition interval in a first mode and a second mode according to an exemplary embodiment.

[0130] Reference Figure 6 , the upper figure is a time-frequency diagram of a transmission signal sent at a first pulse repetition interval 610 in a first mode, and the lower figure is a time-frequency diagram of a transmission signal sent at a second pulse repetition interval 620 in a second mode.

[0131] In addition, Figure 6 In the figure shown, the solid line represents the chirp generated by Tx1, and the dotted line represents the chirp generated by Tx2. Figure 5 As shown, in the first mode, there is only the chirp generated by Tx1 (solid line), and in the second mode, there are both the chirps generated by Tx1 and Tx2 (solid line and dashed line).

[0132] in addition, Figure 6 The illustrated diagram shows that the first pulse repetition interval 610 is set to be smaller than the second pulse repetition interval 620. That is, the first mode can be set with a smaller pulse repetition interval than the second mode, so that the maximum detection speed is higher.

[0133] In this case, even if the speed of the target is greater than the maximum detection speed of the second mode, the speed of the target detected in the first mode can be used to correct the received signal in the second mode, so that the accuracy of estimating the direction of the target can be improved.

[0134] In the following, Figures 7 to 10 In the following, a configuration will be described in which a first target and a second target having different speeds are detected and a phase of a received signal is corrected by determining a phase correction condition for each target.

[0135] Figure 7 An example of a configuration for detecting targets having different speeds using a vehicle radar device according to an embodiment is shown.

[0136] Reference Figure 7 , the vehicle radar device 100 according to the embodiment can detect the first target 710 and the second target 740 using the transmission / reception signal, respectively. In this case, the first target 710 can be detected as an object located in a first direction 730 at a first speed 720, and the second target 740 can be detected as an object located in a second direction 760 at a second speed 750, respectively.

[0137] In addition, the first speed 720 may be set to be smaller than the second speed 750 and have a maximum detection speed v smaller than the second mode. max_m2 The size of this will be referred to below Figures 8 to 10 On the other hand, the second speed 750 can be set to be greater than the first speed 720 and greater than the maximum detection speed v of the second mode. max_m2 But it is less than the maximum detection speed v of the first mode max_m1 , which will be referred to below Figures 8 to 10 Give a description.

[0138] In addition, the vehicle radar device 100 according to the embodiment can be used in the same manner as the reference Figure 5 and Figure 6 The first mode and the second mode are respectively performed in the same manner as described. That is, the first mode can use the first transmitting antenna Tx1, and can be set to have a relatively short pulse repetition interval and a relatively large maximum detection speed. In addition, the second mode can use the first transmitting antenna Tx1 and the second transmitting antenna Tx2, and can be set to have a relatively long pulse repetition interval and a relatively small maximum detection speed.

[0139] In this case, in the first mode, both the first target 710 and the second target 740 can be detected without error. On the other hand, in the second mode, the first target 710 can be detected without error. However, since the second target 740 is detected at a speed exceeding the maximum detection speed v of the second mode, max_m2 The second target moves at a second speed 750, so there may be an error in detecting the second target.

[0140] In particular, in the case of a technique for detecting a target using a phase difference between received signals in a radar device, an error may occur between a second target detection direction detected in the second mode and a second direction 760 which is an actual direction of the second target.

[0141] Therefore, in the case where the vehicle radar device 100 according to the embodiment uses the first mode and the second mode to detect targets, there is no need to correct the received signal of the first target 710 having the first speed 720, however, for the second target 740 having the second speed 750, it is necessary to correct the detection speed, phase and direction in the second mode received signal.

[0142] Figure 8 is a diagram for explaining a configuration for detecting targets having different speeds in a second mode according to an embodiment.

[0143] Reference Figure 8 According to the embodiment, the vehicle radar device 100 can detect the target using the second mode. In addition, the target detection result can be expressed as follows Figure 8 Speed-target diagram shown.

[0144] For example, in Figure 8 In the figure shown, the targets represented by the solid or dotted lines have different actual speeds, but due to the maximum detection speed v of the second mode max_m2 , all targets are represented as being detected with the same velocity.

[0145] However, the target indicated by the solid line indicates the case where the target detected in the second mode actually exists, and the target indicated by the dotted line indicates the case where the target detected in the second mode actually does not exist. These contents can be similarly applied to the following Fig. 9 and Fig.10 middle.

[0146] That is, in Figure 8 , a first object having a first speed 810 and a second object having a second speed 820 are represented as a case where both the first object and the second object are detected as having the first speed 810 in the second mode.

[0147] That is, since the maximum detection speed v of the second mode max_m2 , the second target is not detected as having the second speed 820, but is detected as having the first speed 810 which is equal to the speed of the first target.

[0148] For example, if the speed of the first target is 6 m / s, the speed of the second target is 16 m / s, the first speed 810 is 6 m / s, the second speed 820 is 16 m / s, and the maximum detection speed in the second mode is 10 m / s, the first target can be detected without error, but a detection error will occur in the second target.

[0149] Specifically, in the second mode, the first target and the second target are respectively detected as separate targets, and the first target is detected as having a first speed 810 equal to the actual speed 6 m / s.

[0150] However, since the actual speed of the second target, 16 m / s, exceeds the maximum detection speed of 10 m / s in the second mode, a speed folding phenomenon occurs. Therefore, the following error occurs: the second target is detected as having a first speed 810, i.e., 6 m / s, instead of a second speed 820 equal to the actual speed 16 m / s.

[0151] Fig. 9 is a diagram for explaining a configuration for performing phase correction in a first mode and a second mode according to an exemplary embodiment.

[0152] Reference Fig. 9 , the vehicle radar device 100 according to the embodiment can detect the target using the first mode and the second mode respectively. In addition, the target detection result can be represented as a speed-target graph for each mode. Fig. 9 , the upper figure shows the result of detecting the target in the first mode, and the lower figure shows the result of detecting the target in the second mode.

[0153] in addition, Fig. 9 A case where a first target having an actual first speed 910 is detected as having the first speed 910 in both the first mode and the second mode is shown.

[0154] For example, when the actual speed of the first target is 6 m / s, the first speed 910 is 6 m / s, the maximum detection speed in the first mode is 20 m / s, and the maximum detection speed in the second mode is 10 m / s, the first target can be detected without error in both the first mode and the second mode.

[0155] In addition, it is possible to determine whether a phase correction condition is satisfied by using the detection result, so that phase correction can be performed according to the determination result. Here, the phase correction condition may include at least one of a phase correction condition based on Doppler frequency information and a phase correction condition based on phase difference information, as described above with respect to the signal processor 120.

[0156] As an example, regarding the phase correction condition based on the Doppler frequency, the following Equation 2 may be exemplarily applied to a case where it is determined that no correction is required because no error occurs.

[0157] [Equation 2]

[0158]

[0159] Here, f d_m1 is the Doppler frequency measured in the first mode, f d_m2max is the maximum Doppler frequency of the second mode.

[0160] That is, in the case of determining whether the set phase correction condition is satisfied based on the Doppler frequency information of the first target included in the first mode reception signal and the second mode reception signal, in the first mode, since the Doppler frequency f is determined d_m1 Less than the maximum Doppler frequency f of the first target in the second mode d_m2max , so it can be determined that no phase correction needs to be performed.

[0161] As another example, regarding the phase correction condition based on the phase difference, the following Equation 3 may be exemplarily applied to a case where it is determined that no correction is required because no error occurs.

[0162] [Equation 3]

[0163] 0<ΔΦ<π

[0164] Here, ΔΦ represents phase difference information.

[0165] That is, when determining whether the set phase correction condition is met based on the phase difference information of the first target included in the first mode received signal and the second mode received signal, in the first mode, since it is determined that the phase difference of the first target does not exceed π, it can be determined that phase correction does not need to be performed.

[0166] As described above, in the case where it is determined that phase correction is not required, the following Equation 4 may be exemplarily applied to each signal.

[0167] [Equation 4]

[0168]

[0169]

[0170] That is, in the second mode the received signal has a Doppler frequency f d_m2In the case of a signal, if it is determined that phase correction is not required because the phase correction condition based on the Doppler frequency information and the phase correction condition based on the phase difference information of the first mode received signal are not satisfied, then as in the above equation 4, phase correction is not performed on the second mode received signal.

[0171] Fig.10 is a diagram for explaining a configuration for performing phase correction in a first mode and a second mode according to another embodiment.

[0172] Reference Fig.10 According to another embodiment, the vehicle radar device 100 can detect a target by using the first mode and the second mode respectively. Fig.10 , the upper figure shows the result of detecting the target in the first mode, and the lower figure shows the result of detecting the target in the second mode.

[0173] in addition, Fig.10 A case where a second target having an actual second speed 1020 is detected as having the second speed 1020 in the first mode and is detected as having the first speed 1010 in the second mode is shown.

[0174] For example, when the actual speed of the second target is 16 m / s, the first speed 1010 is 6 m / s, the second speed 1020 is 16 m / s, the maximum detection speed in the first mode is 20 m / s, and the maximum detection speed in the second mode is 10 m / s, the second target is detected without error in the first mode, but a detection error occurs in the second mode.

[0175] In addition, whether or not the phase correction condition is satisfied can be determined by using the detection result, so that the phase correction can be performed according to the determination result.

[0176] For example, regarding the phase correction condition based on the Doppler frequency, the following Equation 5 may be exemplarily applied to determine the situation where correction is required.

[0177] [Equation 5]

[0178]

[0179] That is, in the case of determining whether the set phase correction condition is satisfied based on the Doppler frequency information of the first target included in the first mode reception signal and the second mode reception signal, since the Doppler frequency f of the first target in the first mode is determined d_ml Exceed the maximum Doppler frequency f of the first target in the second mode d_m2max , so it can be determined that phase correction is needed.

[0180] As another example, regarding the phase correction condition based on the phase difference, the following Equation 6 may be exemplarily applied to determine a situation where correction is required.

[0181] [Equation 6]

[0182] π<ΔΦ<2π

[0183] That is, when determining whether the set phase correction condition is satisfied based on the phase difference information of the first target included in the first mode reception signal and the second mode reception signal, since it is determined that the phase difference of the first target in the first mode exceeds π, it can be determined that phase correction is required.

[0184] As described above, in the case where it is determined that phase correction is required, the following Equation 7 may be exemplarily applied to each signal.

[0185] [Equation 7]

[0186]

[0187]

[0188] That is, the Doppler frequency should actually be calculated from the second mode received signal as f d_m2 +f d_2max , but can be calculated as f d_m2 In this case, if phase correction is determined to be required by satisfying at least one of the phase correction condition based on Doppler frequency information and the phase correction condition based on phase difference information of the first mode received signal, phase correction can be performed on the second mode received signal as shown in Equation 7.

[0189] Specifically, the phase of the received signal may be corrected by adding the exp(jπ) portion in the above equation 7. As an example, equation 7 indicates that the phase of the received signal is corrected by adding exp(jπ) to the received signal of the second transmitting antenna Tx2.

[0190] However, as another example, the second mode reception signal may be corrected by correcting both the reception signal of the first transmission antenna Tx1 and the reception signal of the second transmission antenna Tx2. tx2 [f d_m2 +f d_m2max ] The corresponding received signal is added with exp(jπ) and combined with S tx1 [f d_m2 +f d_m2max ]The corresponding received signal is added with exp(jπ) to correct the phase of the received signal.

[0191] Fig.11is a diagram for explaining states before and after phase correction according to an exemplary embodiment.

[0192] Reference Fig.11 , in the case where a target with an actual direction of 0° is detected, the situation before phase correction (upper figure), the situation after correct correction (middle figure), and the situation after incorrect correction (lower figure) are respectively shown as azimuth-(signal) amplitude diagrams. Here, in all three figures, the part with an azimuth of 0° is represented as having a common center line 1110.

[0193] Fig.11 The upper figure in FIG. 1 shows a case where a target located at an actual direction of 0° is erroneously detected as an azimuth corresponding to the peak 1120 before the correction of the received signal. There may be various reasons for such a detection error. Specifically, a case where at least one of the target's speed, Doppler frequency, and phase is erroneously detected may also be a cause of the above detection error.

[0194] In this case, it is necessary to resolve the detection error of the received signal by performing phase correction on the received signal according to the present disclosure.

[0195] Fig.11 The middle figure in FIG. 1 shows a received signal after phase correction is correctly performed according to the present disclosure. That is, through correct phase correction, the situation in which at least one of the speed, Doppler frequency and phase of the target is erroneously detected in the received signal can be corrected.

[0196] In this case, the received signal is detected as an azimuth corresponding to the corrected peak 1130, which coincides with the actual direction of the target 0°, thereby resolving the measurement error of the target direction.

[0197] Unlike the phase correction according to the present disclosure, Fig.11 The following figure in shows a received signal after error correction is performed. For example, in the case where phase correction is performed by adding +π to a portion of the received signal in which at least one of the speed, Doppler frequency, and phase of the target is erroneously detected, if phase correction is performed by adding -π or +2π, or when the received signal is corrected in another erroneous manner, a signal such as Fig.11 The result is shown in the figure below.

[0198] In this case, the received signal can result in the detection of two azimuth angles corresponding to the corrected first peak 1140 and the second peak 1150 for a target whose actual direction is 0°, that is, the errors of the two targets, and each of the azimuth angles corresponding to the corrected first peak 1140 and the corrected second peak 1150 is detected as an error different from the actual direction of the target 0°.

[0199] That is, in the case where an error occurs when estimating the direction of a target, the error can be resolved if the received signal is correctly corrected. However, if an incorrect or erroneous correction is performed, the error in estimating the direction of the target increases, or an error in misestimating the number of detected targets may occur.

[0200] The vehicle radar device 100 may be implemented to include an electronic control unit (ECU), a microcomputer, or the like.

[0201] In an embodiment, a computer system (not shown) such as the vehicle radar device 100 may be implemented as an electronic control unit (ECU). The electronic control unit may include at least one or more elements of one or more processors, memories, storage units, user interface input units, and user interface output units that can communicate with each other through a bus. In addition, the computer system may also include a network interface for connecting to a network. The processor may be a CPU or a semiconductor device that executes processing instructions stored in a memory and / or storage unit. The memory and storage unit may include various types of volatile / non-volatile storage media. For example, the memory may include ROM and RAM.

[0202] More specifically, the vehicle radar device 100 according to the present embodiment and the signal processor 120 and the controller 130 included therein may be implemented as a module of a control device or ECU of a radar system mounted on a vehicle.

[0203] The control device or ECU of such a radar system may include a processor, a storage device such as a memory, and a computer program capable of performing specific functions. In addition, the signal processor 120 and the controller 130 may be implemented as software modules capable of performing their respective functions.

[0204] That is, the signal processor 120 and the controller 130 according to the present embodiment may be implemented as respective software modules and stored in a memory, and each software module may be executed at a specific time point in an operation processing unit such as an ECU included in the vehicle radar system.

[0205] Hereinafter, the vehicle radar device 100 will be briefly described again in terms of the control method. The repeated contents of the above description are omitted as needed, but all of them are applicable to the following method description.

[0206] Fig.12 is a flowchart illustrating a control method of a vehicle radar device according to the present disclosure.

[0207] Reference Fig.12According to the present disclosure, the control method of the vehicle radar device may include: a signal sending / receiving step S1210, sending a transmission signal using a transmitting antenna and receiving a reception signal reflected from a target using a receiving antenna; a signal processing step S1220, determining target direction information by using a phase difference between reception signals received from each receiving antenna; and a mode control step S1230, controlling to respectively execute a first mode and a second mode of sending and receiving signals at different pulse repetition intervals.

[0208] In the signal transmission / reception step S1210, at least two or more transmission antennas and reception antennas may be used, respectively. In addition, in some cases, all antennas may be used or only some antennas may be used. Specifically, in the signal transmission / reception step S1210, regarding the configuration of the transmission antenna and the reception antenna, at least one of MIMO, SIMO, MISO, and SISO technologies may be used.

[0209] In the signal transmission / reception step S1210, the transmission signal and the reception signal may be implemented as using a transmission channel and a reception channel respectively, and may be implemented as using a synthesis channel. Here, the synthesis channel may be implemented as a change in the amplitude and phase of the reception signal with respect to the transmission signal and its reflected signal, and the transmission signal and the reception signal may also be synthesized and processed.

[0210] For example, in a configuration including two transmitting antennas including a first transmitting antenna Tx1 and a second transmitting antenna Tx2 and four receiving antennas including a first receiving antenna Rx1, a second receiving antenna Rx2, a third receiving antenna Rx3 and a fourth receiving antenna Rx4, if a signal is transmitted from Tx1 and a reflected signal is received from Rx4, the signal can be processed in a synthetic channel of Tx1-Rx4.

[0211] Meanwhile, the signal transmitted and received in the signal transmission / reception step S1210 may be controlled in the mode control step S1230. In this case, the signal transmission / reception control may be performed based on preset setting values ​​required for signal transmission / reception, such as the number of transmission antennas and reception antennas used respectively and the pulse repetition interval.

[0212] The signal processing step S1220 may include determining phase information about the phase of each signal based on the signals transmitted and received by each antenna, target direction information about the direction of the target from the radar positioning, etc. In addition, signals transmitted and received in different modes may be processed separately or may be processed together.

[0213] For example, in the signal processing step S1220, if the signal is sent and received in the first mode and the second mode respectively, the phase difference information and the target direction information can be determined by using only the first mode received signal or only the second mode received signal. Alternatively, the phase difference information and the target direction information can be determined by using information of both the first mode received signal and the second mode received signal.

[0214] In addition, in the signal processing step S1220, phase difference information between reception signals received from each reception antenna may be determined, and target direction information may be determined using the phase difference information.

[0215] The phase difference information can be determined by comparing the phase information of each received signal, or the phase difference information can be calculated using information included in two or more received signals received from at least two receiving antennas. In addition, the target direction information can be determined based on the arrival angle information of the reflected signal of the target of the transmitted signal.

[0216] Meanwhile, in the signal processing step S1220, if it is determined that the preset phase correction condition is satisfied, the phase of the received signal may be corrected. The phase correction condition may be set to at least one or more conditions, and if one of the phase correction conditions is satisfied, phase correction may be performed.

[0217] As an example, the phase correction condition may be set based on the phase difference information, or the phase correction condition may be set based on the Doppler frequency information and the maximum Doppler frequency information of the received signal.

[0218] As described above, since the target direction information can be determined based on the phase difference information between the received signals, the target direction information can be corrected by correcting the phase of the received signal. That is, the estimation accuracy of the target direction can be improved by phase correction.

[0219] In the mode control step S1230, the transmission and reception of the signal can be controlled based on a preset control setting value. Here, the control setting value may include at least one of the transmission / reception antenna specification, the transmission time of the signal, the frequency, the radiation direction and the intensity. Here, the transmission time of the signal can be set as a pulse repetition interval.

[0220] The mode control step S1230 may include controlling signal transmission / reception based on different control setting values ​​of each mode by setting control setting values ​​of at least two or more modes differently. In addition, according to the control setting value of each mode, part or all of the change detection performance may be controlled.

[0221] For example, control can be performed by setting a control setting value to use the first transmitting antenna to transmit signals at a first pulse repetition interval in the first mode, and to use the first transmitting antenna and the second transmitting antenna to transmit signals at a second pulse repetition interval in the second mode.

[0222] For example, in the mode control step S1230, the control setting values ​​of the first mode and the second mode may be set so that the first pulse repetition interval is smaller than the second pulse repetition interval. In this case, the maximum detection speed of the first mode is greater than the maximum detection speed of the second mode, and the maximum detection range of the first mode becomes smaller than the maximum detection range of the second mode, so that the target detection performance of each mode can be changed.

[0223] Meanwhile, in the mode control step S1230, the first mode and the second mode may be controlled to be executed in units of time or frame, and the first mode and the second mode may be controlled by presetting an execution time, an execution order, and the like.

[0224] For example, in the mode control step S1230, the first mode and the second mode may be controlled to be executed within one frame. That is, when the radar performs one scan, the first mode and the second mode may be controlled to be executed within the scan range.

[0225] As described above, if the first mode and the second mode are controlled to be executed within a frame range, they will not become larger than a specific size at the measurement time point. Therefore, according to the present disclosure, when the measurement results of the position and speed of the target of each mode are compared and corrected with the measurement results of other modes, the accuracy of the target measurement can be improved.

[0226] In this case, the first mode and the second mode may be set to be executed simultaneously, or may be set to be executed separately from each other. Here, if the first mode and the second mode are executed separately from each other, a time division multiplexing (TDM) method of transmitting and receiving signals at different times may be used.

[0227] In addition, if the first mode and the second mode are controlled by time division multiplexing, it can be set to execute the first mode first and then the second mode.

[0228] For example, if the pulse repetition interval of the first mode is set small, even if the speed of the target exceeds the maximum detection speed of the second mode, the result of the first mode executed first can be used to correct the second mode reception signal, thereby improving the accuracy of the speed and angle of the target measurement.

[0229] As another example, if the pulse repetition interval of the first mode is set large, even if the distance of the target exceeds the maximum detection range of the second mode, the result of the first mode executed first can be used to correct the second mode received signal, thereby improving the accuracy of the speed and angle of the target measurement.

[0230] In addition, in the mode control step S1230, both the first mode and the second mode may be controlled to be executed within one frame, and in this case, the first mode may be controlled to be executed first and then the second mode. In addition, if the phase correction of the received signal is performed by the signal processor 120, the signal transmission / reception and control of each mode may be performed by reflecting the correction content thereafter.

[0231] Fig.13 is a flow chart of signal processing steps according to an embodiment.

[0232] Reference Fig.13 According to the embodiment, the signal processing step S1220 may include a correction condition setting step S1310, a correction condition determining step S1320 and a phase correction step S1330.

[0233] In the correction condition setting step S1310, at least one phase correction condition regarding the received signal may be set.

[0234] As an example, the phase correction condition may be set based on the phase difference information of the received signal. As a specific example, the phase correction condition may be a condition that determines that the phase difference information between the received signal received by reflection of the transmitted signal of the first transmitting antenna and the received signal received by reflection of the transmitted signal of the second transmitting antenna is π or greater. In addition, if the phase correction condition is satisfied, phase correction may be performed.

[0235] As another example, the phase correction condition may be set based on the Doppler frequency information and the maximum Doppler frequency information of the received signal. As a specific example, the phase correction condition may be set such that phase correction is performed when the Doppler frequency information of the first mode received signal exceeds the maximum Doppler frequency information of the second mode received signal.

[0236] In the correction condition determination step S1320, it may be determined whether the received signal satisfies the phase correction condition set in the correction condition setting step S1310.

[0237] In this case, if all of at least one or more phase correction conditions are not satisfied, phase correction may not be performed.

[0238] On the other hand, if one or more of the preset phase correction conditions are satisfied, phase correction may be performed.

[0239] In addition, in the correction condition determination step S1320, in a state where two or more modes having different control setting values ​​are executed, determination of whether the phase correction condition is satisfied may be performed by comparing the setting value and the measurement value of each mode.

[0240] For example, in a case where the first mode transmits a signal at a first pulse repetition interval and the second mode transmits a signal at a second pulse repetition interval, the maximum detection speed and the maximum detection range may differ according to the difference in the pulse repetition interval in each mode.

[0241] That is, if the first pulse repetition interval is smaller than the second pulse repetition interval, the maximum detection speed of the first mode can be greater than the maximum detection speed of the second mode, and the maximum detection range of the first mode can be smaller than the maximum detection range of the second mode. In addition, received correction can be performed by using this characteristic.

[0242] In the phase correction step S1330, if one or more of the various phase correction conditions are met, the phase of the received signal may be corrected by adding π to the phase of the received signal. In this case, the phase correction may be performed on all or part of the measured received signal.

[0243] For example, if a reflected signal of a signal transmitted by a first transmitting antenna is received in a first mode, and a reflected signal of a signal transmitted by a first transmitting antenna and a second transmitting antenna is received in a second mode, phase correction can be performed only on a received signal obtained by receiving the reflected signal of a signal transmitted by the second transmitting antenna in the second mode.

[0244] As another example, if the speed of the target is less than the maximum detection speed of the first mode but exceeds the maximum detection speed of the second mode, a target measurement error may occur in the second mode.

[0245] In this case, the detection signal of the first mode can be used to correct the detection signal of the second mode. That is, the second mode reception signal can be corrected by using at least one of the speed information, distance information, Doppler frequency information and phase difference information of the target in the first mode reception signal.

[0246] As another example, if the distance of the target is less than the maximum detection range of the second mode but exceeds the maximum detection range of the first mode, a target measurement error may occur in the first mode.

[0247] In this case, the detection signal of the first mode can be corrected using the detection signal of the second mode. That is, the first mode reception signal can be corrected by using at least one of the speed information, distance information, Doppler frequency information and phase difference information of the target in the second mode reception signal.

[0248] As described above, according to the vehicle radar device and the control method thereof of the present disclosure, the accuracy of the direction measurement and the speed measurement of the target can be improved by using two or more modes having different modulation schemes.

[0249] In addition, errors that occur when measuring the direction and speed of a target can be resolved by correcting phase measurement errors using the received signal of each mode.

[0250] The above description is presented to enable those skilled in the art to make and utilize the technical ideas of the present disclosure, and the above description is provided in the context of specific applications and their requirements. Various modifications, additions and substitutions to the described embodiments will be apparent to those skilled in the art without departing from the ideas and scope of the present disclosure, and the general principles defined herein may be applied to other embodiments and applications.

Claims

1. A vehicle radar device, comprising: an antenna unit, comprising a transmitting antenna for transmitting a transmitting signal and a receiving antenna for receiving a receiving signal reflected from a target; a signal processor configured to determine target direction information by using a phase difference between the reception signals received from the respective reception antennas; as well as a controller configured to control to respectively perform a first mode and a second mode of transmitting and receiving signals at different pulse repetition intervals, wherein the signal processor is configured to correct the second mode reception signal received in the second mode based on the first mode reception signal received in the first mode when a preset phase correction condition is met, The antenna unit includes a first transmitting antenna and a second transmitting antenna. wherein the transmit signal is transmitted using the first transmit antenna in the first mode, and the transmit signal is transmitted using the first transmit antenna and the second transmit antenna in the second mode, and The controller controls to execute the first mode and the second mode such that a pulse repetition interval of the first mode is set to a value smaller than a pulse repetition interval of the second mode.

2. The radar device according to claim 1, wherein the signal processor determines phase difference information included in the first mode received signal and the second mode received signal of each target based on phase information included in each received signal, and The phase correction condition is a condition set to perform phase correction when the phase difference information exceeds π.

3. The radar device according to claim 1 , wherein the signal processor determines Doppler frequency information and maximum Doppler frequency information of each target based on frequency information and target speed information included in each received signal, and The phase correction condition is a condition set to perform phase correction when the Doppler frequency information of the first mode reception signal exceeds the maximum Doppler frequency information of the second mode reception signal. 4 . The radar apparatus according to claim 1 , wherein when the phase correction condition is satisfied, the signal processor corrects the second mode reception signal by adding a phase difference π to the phase of the second mode reception signal. 5 . The radar apparatus according to claim 1 , wherein the controller controls to execute the first mode and the second mode within one frame. 6 . The radar apparatus according to claim 5 , wherein the controller controls to execute the second mode after executing the first mode.

7. A method for controlling a vehicle radar device, comprising: transmitting a transmit signal using a transmit antenna and receiving a receive signal reflected from a target using a receive antenna; determining target direction information by using a phase difference between the received signals received from the respective receiving antennas; as well as controlling to respectively execute a first mode and a second mode for transmitting and receiving signals at different pulse repetition intervals, Wherein determining the target direction information includes correcting the second mode received signal received in the second mode based on the first mode received signal received in the first mode when a preset phase correction condition is met, The sending of the transmission signal includes sending the transmission signal using a first transmission antenna and a second transmission antenna, wherein the transmit signal is transmitted using the first transmit antenna in the first mode, and the transmit signal is transmitted using the first transmit antenna and the second transmit antenna in the second mode, and wherein the controlling includes controlling to execute the first mode and the second mode such that a pulse repetition interval of the first mode is set to a value smaller than a pulse repetition interval of the second mode.

8. The control method according to claim 7, wherein determining the target direction information comprises determining phase difference information included in the first mode received signal and the second mode received signal of each target based on phase information included in each received signal, and The phase correction condition is a condition set to perform phase correction when the phase difference information exceeds π.

9. The control method according to claim 7, wherein determining the target direction information comprises determining Doppler frequency information and maximum Doppler frequency information of each target based on frequency information and target speed information included in each received signal, and The phase correction condition is a condition set to perform phase correction when the Doppler frequency information of the first mode reception signal exceeds the maximum Doppler frequency information of the second mode reception signal. 10 . The control method according to claim 7 , wherein determining the target direction information includes correcting the second mode reception signal by adding a phase difference π to the phase of the second mode reception signal when the phase correction condition is satisfied. 11 . The control method according to claim 7 , wherein the controlling includes controlling to execute the first mode and the second mode within one frame.

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