Vehicle radar device, radar device control method, and vehicle radar system

Abstract

The present disclosure relates to a radar device for a vehicle, a control method for the radar device, and a radar system for a vehicle. According to an embodiment, the radar device includes: a transceiver, which is controlled to transmit a transmission signal in an operating frequency band according to a selection mode among a plurality of frequency band modes, and receive a reception signal through a receiving antenna; and a mode selector, which dynamically determines one of the plurality of frequency band modes as a selection mode based on at least one of a target distance to a target and a maximum detection distance of each frequency band. According to an embodiment of the present disclosure, the distance resolution of the radar can be optimized by dynamically changing the frequency bandwidth associated with the maximum detection distance according to the target distance under specific driving conditions.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to a vehicle radar device, a control method of the radar device, and a vehicle radar system. More specifically, embodiments of the present disclosure relate to a radar device that dynamically changes an operating frequency band of a radar signal according to a distance to a target or a maximum detection distance, so as to improve the detection performance of horizontal information in a multi-receiving path environment of the radar signal. Background Art

[0002] Radar devices installed in vehicles, etc. are widely used as sensor devices for vehicle control. The radar device can transmit electromagnetic waves having a predetermined frequency, receive signals reflected from an object, and process the received signals to extract position, speed information, etc. of the object.

[0003] The target information acquired by the vehicle radar may include position information including distance information and angle information, and relative speed information between the host vehicle and the target.

[0004] In the case where distance, velocity, and space (angle) information constituting three domains of target information are independently obtained for each target, contamination of signal components between multiple targets does not occur.

[0005] However, if the vehicle is traveling on a road having guardrails, sound barriers, tunnels, etc., it may happen that radar signals are sent and received through multiple paths due to such stationary structures.

[0006] In such a multi-receive path environment, multiple signals may overlap, so that target information (especially horizontal angle information or horizontal position information) may be inaccurate.

[0007] Specifically, a single target may be recognized as two targets (real target and ghost) existing in several lateral positions.

[0008] Furthermore, it is possible to infinitely identify whether the target is a single target or multiple targets over the range-velocity domain.

[0009] To solve such a problem, it is necessary to improve the distance resolution. Therefore, the number of antennas of the radar device can be increased through hardware, the antenna separation distance can be adjusted, or the frequency bandwidth of the radar signal can be increased.

[0010] However, due to increasing cost and space issues, there may be certain limitations in the hardware solution of the radar device.

[0011] Furthermore, if the frequency bandwidth is increased, the distance resolution is improved, however, there is a disadvantage that the maximum detection distance may be reduced.

[0012] Therefore, there is a need for a method that can ensure the lateral position detection performance of a target under certain conditions such as a multi-receive path environment without degrading other performances of the radar device. Summary of the invention

[0013] In this context, an embodiment of the present disclosure provides a method for improving the level detection performance of a radar device.

[0014] Embodiments of the present disclosure provide a vehicle radar device, a control method thereof, and a radar system that are capable of accurately acquiring lateral position information and the like of a target in a multi-reception path environment.

[0015] Embodiments of the present disclosure provide a vehicle radar device, a control method thereof, and a radar system capable of dynamically optimizing the range resolution of a radar by dynamically changing a frequency bandwidth associated with a maximum detection distance according to a distance or range of a target under specific driving conditions.

[0016] Embodiments of the present disclosure provide a vehicle radar device, a control method thereof, and a radar system capable of dynamically changing the horizontal detection performance of a radar by dynamically switching to one of a plurality of frequency band modes based on a detected target distance when a specific driving condition is satisfied.

[0017] According to one aspect of the present disclosure, a vehicle radar device is provided, the vehicle radar device comprising: an antenna unit, the antenna unit comprising a transmitting antenna for transmitting a transmission signal around a vehicle and a receiving antenna for receiving a reception signal reflected from a target; a transceiver, the transceiver being controlled to transmit the transmission signal in an operating frequency band according to a selection mode among a plurality of frequency band modes through the transmitting antenna, and the transceiver being controlled to receive the reception signal through the receiving antenna; a signal processor, the signal processor processing the reception signal received from the receiving antenna to acquire target information; and a mode selector, the mode selector dynamically determining one of the plurality of frequency band modes as the selection mode based on at least one of a target distance to a target acquired from the signal processor and a maximum detection distance of each frequency band.

[0018] In addition, the vehicle radar device according to the embodiment may further include a condition determiner, which determines the driving condition of the vehicle based on the information obtained about the stationary obstacles around the vehicle, and activates the mode selector if the driving condition of the vehicle corresponds to a specific driving condition.

[0019] In this case, the specific driving condition may include a condition in which at least one of a guardrail, a soundproof wall, a tunnel, and an overpass exists around the vehicle.

[0020] Information about obstacles around the vehicle may be obtained from target information obtained from the signal processor or from other sensor information obtained from additional vehicle detection sensors.

[0021] In addition, each frequency band mode included in the multiple frequency band modes can be defined by a unique operating frequency band and a maximum detection distance corresponding to the unique operating frequency band, and the mode selector can determine the frequency band mode with the maximum operating frequency band as the selected mode among one or more frequency band modes whose maximum detection distance is greater than the target distance.

[0022] The signal processor may perform a fast-time first Fourier transform, i.e., a first FFT, on the received signal to obtain a time component according to the distance, and a slow-time second Fourier transform, i.e., a second FFT, and compress the signal existing at each distance according to the speed to calculate the range-speed information of the target.

[0023] Furthermore, the signal processor may determine whether the target is a single target or multiple targets based on the range-speed information calculated according to the selection mode.

[0024] The range resolution of an object at the target distance is maximized according to the operating frequency band of the selected mode determined by the mode selector.

[0025] According to one aspect of the present disclosure, a control method for a vehicle radar device is provided. The control method for the vehicle radar device may include: transmitting a transmission signal in an operating frequency band according to a selection mode among a plurality of frequency band modes through a transmission antenna, and receiving a reception signal reflected from an object through a reception antenna; processing the reception signal received from the reception antenna to acquire target information; dynamically determining the selection mode from one of the plurality of frequency band modes based on at least one of a target distance to a target acquired in processing the reception signal and a maximum detection distance of each frequency band; and transmitting the transmission signal in an operating frequency band corresponding to the selection mode during a subsequent scanning operation.

[0026] According to another aspect of the present disclosure, a vehicle radar system is provided. The vehicle radar system may include: a transmitting antenna for transmitting a transmission signal in an operating frequency band according to a selection mode among a plurality of frequency band modes; a receiving antenna for receiving a reception signal reflected from a target; and a signal processing device for processing the reception signal received from the receiving antenna to obtain target information, and dynamically determining the selection mode from one of the plurality of frequency band modes based on at least one of a target distance to the target obtained in processing the reception signal and a maximum detection distance of each frequency band, and transmitting the transmission signal in an operating frequency band corresponding to the selection mode during a subsequent scanning operation.

[0027] According to the embodiments of the present disclosure, the horizontal detection performance of the radar device can be improved.

[0028] Furthermore, according to the embodiment, the lateral position information of the target can be accurately acquired in a multi-receiving path environment.

[0029] Additionally, the range resolution of the radar may be dynamically optimized by dynamically changing the frequency bandwidth associated with the maximum detection range according to the target range of the target under specific driving conditions.

[0030] In addition, according to an embodiment of the present disclosure, if a specific driving condition is satisfied, the horizontal detection performance of the radar device may be dynamically changed by dynamically switching to one of a plurality of frequency band modes based on a target distance of a detected target. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 An object detection method of a general vehicle radar sensor is shown, and a mid / long-range detection area and a short-range detection area are shown.

[0032] Figure 2 An example of a multi-receive path environment that may degrade the detection performance of a radar device is shown.

[0033] Figure 3 Target information for a case where multiple targets are detected in a normal environment is shown.

[0034] Figure 4 An example of target information in a case where a target is not accurately detected in a multi-reception path environment is shown.

[0035] Figure 5 A configuration of a vehicle radar device according to an embodiment of the present disclosure is shown.

[0036] Figure 6 An embodiment of an antenna unit included in a vehicle radar device according to an embodiment of the present disclosure is shown.

[0037] Figure 7 The principle of acquiring range-speed information of a target by a signal processor of a radar device according to an embodiment is shown.

[0038] Figure 8 An example of a plurality of frequency band mode setting information according to an embodiment of the present disclosure is shown.

[0039] Fig. 9 The change in detection performance of a target according to a dynamic pattern change according to an embodiment of the present disclosure is shown.

[0040] Fig.10 : is a flowchart showing the overall flow of a control method of a radar device according to an embodiment of the present disclosure.

[0041] Fig.11 is a flowchart of a signal processing method provided by a radar device according to an embodiment of the present disclosure.

[0042] Fig.12 The difference in signal waveform and frequency band when the radar device according to the embodiment of the present disclosure switches from the first mode to the second mode is shown.

[0043] Fig.13 A configuration of a vehicle radar system according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0044] 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 indicate the same or similar components even if they 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 well-known functions and components incorporated herein may make the subject matter of some embodiments of the present disclosure unclear, the description will be omitted.

[0045] 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, order, sequence or quantity of the elements, but is only used to distinguish the corresponding elements from other elements.

[0046] When it is mentioned that a first element is “connected or coupled”, “contacting or overlapping”, etc., to a second element, it should be interpreted that not only the first element can be “directly connected or coupled” or “directly contacting or overlapping” to the second element, but also a third element can be “inserted” between the first element and the second element, or the first element and the second element can be “connected or coupled”, “contacting or overlapping”, etc. to each other via a fourth element.

[0047] Figure 1 An object detection method of a general vehicle radar sensor is shown, and a mid / long-range detection area and a short-range detection area are shown.

[0048] like Figure 1 As shown, when detecting an object near a vehicle, the vehicle radar sensor is required to have a medium / long-range detection function for detecting a long-range target ahead and a short-range detection function for detecting a short-range target near the vehicle.

[0049] In vehicles using radar sensors, various types of driver assistance systems (DAS) may be used to assist the driver in driving.

[0050] In an adaptive cruise control (ACC) system for following a vehicle ahead, it is necessary to detect medium and long-range targets ahead of the vehicle's traveling direction.

[0051] At the same time, in an automatic emergency braking system (AEB) or an automatic emergency steering system (AES) for emergency braking or steering a vehicle when there is an obstacle ahead, or in a lane change assist (LCA) system for preventing a collision with an obstacle in an adjacent lane when changing lanes, near-field obstacles near the vehicle need to be detected with high accuracy.

[0052] That is, the vehicle radar device is required to measure target information such as distance, speed, angle information, etc. of various targets in various ranges with high accuracy.

[0053] In particular, in a general two-dimensional road driving environment, it is necessary to accurately measure the lateral position information of a target including the distance and horizontal angle of the target, rather than the vertical information.

[0054] For this reason, Figure 1 As shown in the above figure, the vehicle radar device 10 may have: a long-range detection area 12 having a relatively narrow detection angle and a long detection distance for medium and long-range sensing, and a wide sensing angle; and a short-range detection area 14 having a wide detection angle and a small detection distance.

[0055] Such a vehicle radar device may need to transmit a transmission signal in a medium- and long-range transmission beam pattern for medium- and long-range detection, and transmit a transmission signal in a short-range transmission beam pattern for short-range detection that is different from the medium- and long-range transmission beam pattern.

[0056] However, since such a radar device needs to include an antenna structure and two modes of signal processing units according to a detection range, the structure of the radar device may be complicated and the load of a signal processing operation may increase.

[0057] To solve this problem, it is necessary to integrate the medium / long-range radar and the short-range radar in the vehicle radar. In addition, in order to integrate the medium / long-range radar and the short-range radar, a method of using a transmitting antenna for each mode and a common receiving antenna can be considered.

[0058] That is to say, Figure 1 As shown in the figure below, a radar device having a single detection area is provided, however, by achieving different horizontal information distance resolutions according to the distance of the target, a radar device with a simple structure and improved target horizontal information accuracy can be provided.

[0059] In addition, in addition to the target's distance, speed, and horizontal angle, vehicle radar can also provide vertical information, such as the target's elevation angle.

[0060] To estimate the elevation angle, the power of the target signal received from different transmission / reception antennas may be used, or an array antenna in the vertical direction may be used.

[0061] The elevation angle estimated as described above can be used for classification of the target.

[0062] Figure 2 An example of a multi-receive path environment that may degrade the detection performance of a radar device is shown.

[0063] If the vehicle is traveling on a normal road with no surrounding obstacles, the transmitted radar signal is only reflected on the target.

[0064] Therefore, only the main received signal component of the target exists in the received signal, and in this case, target information such as distance, speed, and angle (space) can be uniquely determined.

[0065] However, if there is a stationary obstacle in front of or to the side of the moving vehicle, such as a protective drainage, a soundproof wall, a tunnel, an overpass, etc., the radar signal may include components of one or more paths that are used as a transmission path for a transmitted signal reaching a target or a reception path for a reflected signal reflected from a target.

[0066] More specifically, Figure 2 The diagram shows an environment in which a stationary obstacle 30 such as a soundproof wall or a guardrail extending longitudinally in the road direction exists on the left side of the road on which the vehicle 20 equipped with the front radar device 10 is traveling.

[0067] In this case, a reception signal reflected from a target as another vehicle 40 ahead may be received by the radar through the first reception path R1 , and may be simultaneously received by secondary reflection from the stationary obstacle 30 through the second reception path R2 .

[0068] In this way, an environment in which two or more transmission and reception paths of the radar signal are formed between the radar device and the target may be referred to as a multi-reception path state.

[0069] In such a multi-reception path environment, in addition to the real target which is the actual other vehicle 40 , there may be a ghost 40 ′ detected outside the stationary obstacle 30 as shown by the dotted line.

[0070] That is, distance-speed information or range-speed information of one real target may be recognized as having various values, and the real target may be represented as an unclear detection area in the range-speed domain as described below.

[0071] Therefore, there is a problem that the distance information of the target is not accurately acquired.

[0072] This phenomenon is more likely to occur in the case where the stationary obstacle 30 includes a longitudinal stationary obstacle such as a guardrail, a soundproof wall, etc. arranged longitudinally in the extending direction of the road, and may also occur when there are other steel tunnels, etc.

[0073] Figure 3 Target information showing a situation where multiple targets are detected in a normal environment, Figure 4 An example of target information in a case where a target is not accurately detected in a multi-reception path environment is shown.

[0074] Figure 3 and Figure 4 Target information in a two-dimensional domain of range-velocity information or distance-velocity information is shown.

[0075] refer to Figure 3 , in a normal environment where multiple reception paths do not occur, targets 1, 2, and 3 (T1, T2, T3) are identified as being distinguishable from each other in the range-velocity domain, so the signal processor of the radar device can accurately detect the three targets.

[0076] However, in Figure 2 As shown, Figure 4 In the illustrated multi-receive path environment, one target T1 has the same (relative) speed, but it can be appreciated that the lateral position of the target has a virtual position (dashed line) that partially deviates from the actual position (solid line).

[0077] Therefore, in Figure 4 In this case, it is difficult for the signal processor of the radar device to identify whether the target T1 is a single target or a plurality of targets, and in particular, there may be a problem that it is impossible to accurately acquire the distance information and horizontal information (horizontal angle) of the target.

[0078] In order to solve the inaccuracy of lateral information, it is necessary to improve the distance resolution. To this end, the number of antennas of the radar device can be increased through hardware, or the antenna separation distance can be adjusted, or the frequency bandwidth of the radar signal can be increased.

[0079] However, there are limitations on hardware solutions for radar devices due to increased costs and space issues.

[0080] In addition, if the frequency bandwidth is increased, the distance resolution is improved, but there is a disadvantage that the maximum detection distance is reduced.

[0081] Therefore, under certain conditions such as a multi-receive path environment, a method is needed that can ensure the lateral position detection performance of the target without degrading other performances of the radar device.

[0082] Therefore, the embodiments of the present disclosure may provide a technical approach that is capable of dynamically changing the horizontal detection performance of a radar by dynamically switching to one of a plurality of frequency band modes based on the detected target distance when a specific driving condition is satisfied.

[0083] Figure 5 A configuration of a vehicle radar device according to an embodiment of the present disclosure is shown.

[0084] Reference Figure 5 , the radar device according to the embodiment may include an antenna unit 100, a transmission / reception unit 200 for transmitting and receiving radar signals, a signal processing unit 300, and a mode selection unit 400. In the present disclosure, the transmission / reception unit 200 may also be referred to as a transceiver, the signal processing unit 300 may also be referred to as a signal processor, and the mode selection unit 400 may also be referred to as a mode selector.

[0085] In addition, the radar device according to the embodiment may further include a situation determination unit 500 for determining a situation in which the mode selection unit operates. In the present disclosure, the situation determination unit 500 may also be referred to as a situation determiner.

[0086] The antenna unit 100 may include a transmission antenna for transmitting a transmission signal around the vehicle and a reception antenna for receiving a reception signal reflected from an object.

[0087] According to the present embodiment, one of the transmitting antenna and the receiving antenna included in the antenna unit 100 may include two or more array antennas spaced apart (horizontally offset) by a predetermined distance in the horizontal direction.

[0088] More specifically, the antenna unit may include two or more transmitting antennas spaced a predetermined distance apart in the horizontal direction and one or more receiving antennas arranged in the vertical direction at the same position as the transmitting antennas. Alternatively, the antenna unit may include one or more transmitting antennas spaced a predetermined distance apart in the horizontal direction and two or more receiving antennas.

[0089] The following will refer to Figure 6 The detailed configuration of the antenna unit used in the radar apparatus according to the present embodiment is described in more detail.

[0090] Meanwhile, the transmission / reception unit 200 according to the present embodiment may be controlled to transmit a transmission signal in an operating frequency band according to a selection mode among a plurality of frequency band modes, and receive a reception signal from a reception antenna.

[0091] The signal processing unit 300 may control the transmission / reception unit 200 to transmit a transmission signal having a specific transmission beam pattern through the transmission antenna unit, and process a reception signal received from the reception antenna to obtain object information.

[0092] The signal processing unit 300 may be represented by other terms such as a control unit and a signal processor, and may be implemented in the form of a digital signal processor (DSP).

[0093] Meanwhile, radar sensor devices can be divided into a pulse type, a frequency modulated continuous wave (FMCW) type, and a frequency shift keying (FSK) type according to a signal type.

[0094] Among them, the FMCW type radar device can use a chirp signal or a ramp signal (a chirp signal or a ramp signal is a signal whose frequency increases over time), and can determine information of an object by using a time difference between a transmission wave and a reception wave and a Doppler shift.

[0095] More specifically, the controller of the radar device may include a signal transmitting / receiving unit 200 for controlling signal transmission / reception through a transmitting / receiving antenna, and a signal processing unit 300 for calculating target information (position, distance, angle, etc.) by using a transmitting signal and a reflected signal received from a receiving antenna.

[0096] The signal transmission / reception unit 200 may include a transmission unit 210 or transmitter and a reception unit 220 or receiver, and the transmission unit 210 may include an oscillator for providing a signal to each transmission antenna to generate a transmission signal. The oscillator may include, for example, a voltage controlled oscillator (VCO).

[0097] The receiving unit 220 included in the signal transmitting / receiving unit 200 may include: a low noise amplifier (LNA) for low-noise amplification of a reflected signal received through a receiving antenna; and a mixer for mixing the low-noise amplified received signal; an amplifier for amplifying the mixed received signal; and an analog-to-digital converter (ADC) for generating received data by digitally converting the amplified received signal.

[0098] The signal processing unit 300 may include a first processing unit and a second processing unit. The first processing unit as a preprocessor of the second processing unit may acquire transmission data and reception data, control generation of a transmission signal in an oscillator based on the acquired transmission data, synchronize the transmission data and reception data, and perform frequency conversion of the transmission data and reception data.

[0099] The second processing unit is a post-processor that performs actual processing using the processing result of the first processing unit. The second processing unit can perform CFAR (constant false alarm rate) calculation, tracking calculation, target selection calculation based on the received data frequency converted by the first processing unit to extract the angle information, speed information and distance information of the target. However, the present disclosure is not limited to this, and if information about the target can be extracted, the technical idea according to the present disclosure can be applied.

[0100] The first processing unit may perform frequency conversion after buffering the acquired transmission data and the acquired reception data at a processable unit sample size per cycle. The frequency conversion performed by the above-mentioned first processing unit may be implemented by using Fourier transform such as Fast Fourier Transform (FFT).

[0101] The second processing unit may perform a second Fourier transform (FFT) on the first Fourier transform (FFT) signal performed by the first processing unit, and the second Fourier transform may be, for example, a discrete Fourier transform (DFT), in particular a chirped discrete Fourier transform (Chirp-DFT).

[0102] The second processing unit may acquire a frequency value corresponding to a number corresponding to a second Fourier transform length K through a second Fourier transform such as Chirp-DFT. The second processing unit may detect the object by calculating a beat frequency having a maximum power during each chirp period based on the acquired frequency value and acquiring speed information and distance information of the object based on the calculated beat frequency.

[0103] The following will refer to Figure 7 The principle of obtaining target information by the signal processing unit is described in more detail.

[0104] Figure 6 An embodiment of an antenna unit included in a vehicle radar device according to an embodiment of the present disclosure is shown.

[0105] refer to Figure 6 The antenna unit 100 according to this embodiment may include two transmitting antennas Tx1, Tx2 and a plurality of receiving antennas Rx. The two transmitting antennas Tx1 and Tx2 may be separated by a certain distance ΔD in the vertical direction, and the plurality of receiving antennas Rx may all have the same vertical position.

[0106] Each of the transmitting antenna and the receiving antenna may have a structure in which 2, 4, or 6 array antennas extend in one direction while having one feeding point, but is not limited thereto.

[0107] Each array antenna constituting a transmitting antenna and a receiving antenna may be composed of a plurality of elements or patches connected to an output line of a distributor, and may extend in an upper direction (upper direction in a vertical direction), wherein a feed port is connected to an input port of a chip including a controller or a distributor as a starting point.

[0108] In addition, the two transmitting antennas Tx1 and Tx2 constituting the transmitting antenna unit can be arranged to be spaced apart by 0.5λ, which is half the wavelength of the transmitting signal, in the horizontal direction (second direction) perpendicular to the vertical direction (first direction) which is the extension direction of each array antenna. In addition, the multiple receiving antennas Rx constituting the receiving antenna unit can also be arranged to be spaced apart by 0.5λ, which is half the wavelength of the transmitting signal.

[0109] Thus, by setting the horizontal distance between the transmitting antenna or the receiving antenna to 0.5λ, which is half the wavelength of the transmitted signal, the angle ambiguity caused by the grating lobe can be eliminated.

[0110] That is, since the distance between the receiving antennas is greater than 0.5λ, which is half the wavelength of the transmitted signal, grating lobes may occur. However, by arranging the horizontal distance between the receiving antennas to be 0.5λ and comparing and compensating the angle information extracted from the channel of each receiving antenna, the angle ambiguity caused by the grating lobes can be minimized.

[0111] In addition, if Figure 6 As shown, since the two transmitting antennas Tx1 and Tx2 are vertically offset by a certain distance, there may be a phase difference due to the vertical offset between a first reception signal transmitted from Tx1 and received from the receiving antenna and a second reception signal transmitted from Tx2 and received from the receiving antenna.

[0112] Therefore, the target distance to the target can be calculated using the time difference between the transmission time and the reception time, and the horizontal information or vertical information of the target can be acquired by using the phase difference between the transmission signal, the first reception signal, and the second reception signal.

[0113] The antenna 100 according to this embodiment does not necessarily have Figure 6 The configuration shown may include one or more transmit antennas and two or more receive antennas having the same vertical position.

[0114] However, in order to ensure wide range adjustment of the distance resolution according to the mode selection of the present embodiment, the number of transmission antennas and reception antennas may be two or more, respectively, so that the maximum distance resolution can be increased.

[0115] In addition, the radar apparatus according to the present embodiment can modulate radar signals transmitted / received from the transmitting antenna or the receiving antenna shifted in the horizontal direction by using different modulation methods.

[0116] The mode selection unit 400 included in the radar apparatus according to the present embodiment may dynamically determine the selection mode from one of a plurality of frequency band modes based on at least one of the target distance to the target and the maximum detection distance of each frequency band obtained from the signal processing unit.

[0117] More specifically, each frequency band mode included in the plurality of frequency band modes set according to the present embodiment may be defined by a unique operating frequency band and a maximum detection distance corresponding to the unique operating frequency band.

[0118] In this case, the mode selection unit 400 according to the present embodiment may determine the band mode having the largest operating frequency band as the selection mode among one or more band modes whose maximum detection distance is greater than the detection target distance.

[0119] That is, the mode selection unit 400 according to the present embodiment may dynamically determine one of a plurality of preset frequency band modes based on the distance of a target detected under a specific condition, and may scan radar signals in an operating frequency band corresponding to the determined selection mode.

[0120] The following will refer to Figure 8 The operation of the mode selection unit is described in more detail.

[0121] In this case, a specific condition for the mode selector operation may be a situation where multiple receiving paths occur due to soundproof walls, guardrails, etc., as shown in FIG. Figures 2 to 4 described.

[0122] To this end, the radar apparatus according to the present embodiment may further include a situation determination unit 500 for determining a situation in which the mode selection unit 400 operates.

[0123] The situation determination unit 500 may determine the driving situation of the vehicle based on the acquired stationary obstacle information around the vehicle, and may perform the function of activating the mode selection unit 400 if a specific driving situation is satisfied.

[0124] In this case, the specific driving condition is a situation where there is at least one of a guardrail, a soundproof wall, a tunnel and an overpass around the vehicle, and the stationary obstacle information around the vehicle can be obtained from the radar sensor information obtained by the signal processing unit 300 or other sensor information of the additional vehicle detection sensor.

[0125] In addition, information about stationary obstacles existing on the road on which the vehicle is traveling can be obtained by receiving information about the road on which the vehicle is traveling using a communication module of the vehicle. For example, the communication module is used to perform communication between a GPS satellite and a vehicle, communication between vehicles, communication between vehicles and infrastructure, communication between vehicles and a server, or internal communication in a vehicle, and the communication module can obtain road information to a destination in real time based on the current position of the vehicle.

[0126] That is, the situation determination unit 500 detects obstacles that continuously exist in the longitudinal direction along the road using the radar information obtained from the signal processing unit, and can determine that a specific driving situation according to the present embodiment is satisfied.

[0127] In addition, the situation determination unit 500 processes the front image data acquired by the image sensor such as a camera or a laser radar, and recognizes that there are stationary obstacles such as soundproof walls and guardrails in front. In this case, the situation determination unit 500 can determine that the specific driving condition according to the present embodiment is satisfied. In addition, in the case where the situation determination unit 500 identifies a stationary obstacle using the road information received through the communication module, the situation determination unit 500 can determine that the specific driving condition according to the present embodiment is satisfied.

[0128] More specifically, the situation determination unit 500 may use radar sensor information or other sensor information, and may identify a stationary obstacle by using techniques such as an entropy-based method, a harmonic-based method, and a machine learning-based method.

[0129] Meanwhile, the signal processing unit 300 according to the present embodiment may acquire the range-speed domain information of the target by applying a two-step fast Fourier transform (2-D FFT) to the received signal.

[0130] Figure 7 The principle of acquiring range-speed information of a target by a signal processor of a radar device according to an embodiment is shown.

[0131] like Figure 7As shown, the signal processing unit 300 according to the present embodiment can perform a first Fourier transform (first FFT) of a fast time on the received signal to obtain a time component according to the distance, and perform a second Fourier transform (second FFT) of a slow time, and compress the signal present at each distance according to the speed to calculate the range-speed information of the target.

[0132] More specifically, if Figure 7 As shown on the left side, the signal processing unit 300 may perform a first Fourier transform (first FFT) as a fast Fourier transform on the radar reception signal including a fast slope or a fast chirp to calculate a range-time graph as a time component according to the range.

[0133] Next, the signal processing unit 300 may perform a second Fourier transform on the range-time component, and may generate a second Fourier transform according to Figure 7 The distances shown on the right are used to calculate the range-speed graph representing the speed information.

[0134] Speed ​​information according to the distance of an object existing around the vehicle can be obtained by using such range-speed information.

[0135] In this case, the identified distance difference Δr associated with the distance resolution and the identified speed difference Δv associated with the speed resolution may be defined by Equations 1 and 2 below.

[0136] [Equation 1]

[0137]

[0138] In Equation 1, c represents the speed of light, BW represents the scanning bandwidth or frequency band (width) of the radar signal, and Δr represents the recognition distance difference.

[0139] BW may represent the width of a frequency band occupied by one chirp signal.

[0140] The distance resolution or range resolution can be defined as the inverse of the identification distance difference Δr.

[0141] That is, when the recognition distance difference Δr corresponding to the specific frequency bandwidth BW decreases, the distance resolution (range resolution) increases, and accurate distance or horizontal position information can be acquired.

[0142] [Equation 2]

[0143]

[0144] In Equation 2, c represents the speed of light, L represents the number of chirps (ie, a signal whose frequency varies with time), Tc represents the duration of the chirp, fc represents the carrier frequency, and Δv represents the recognition speed difference.

[0145] The velocity resolution can be defined as the inverse of the identified velocity difference Δv.

[0146] That is, when the recognition speed difference Δv decreases, the speed resolution increases and a precise target speed can be acquired.

[0147] At the same time, when there are multiple moving targets ahead, each target has a different speed or distance, and the signal component of each target can be separated in the two-dimensional range-velocity domain, such as Figure 3 shown.

[0148] However, if the speeds and ranges of multiple targets are the same or similar to each other, the signal components of each target can be superimposed at a point in the two-dimensional range-velocity domain, e.g. Figure 4 shown.

[0149] In addition, as referenced Figure 2 As mentioned above, in the presence of a stationary obstacle such as a guardrail or a soundproof wall, there is a very high probability that the two signals will be mixed and received from a single target. Figure 4 As shown, multiple signal components can also be superimposed on a point in the two-dimensional range-velocity domain.

[0150] Therefore, it is difficult to distinguish the two targets because there is a slight difference in the range-speed information of the identified targets. In particular, if the angular difference value of the signals received through the two paths is lower than the angular resolution, the targets cannot be distinguished.

[0151] Therefore, in order to classify multiple targets or accurately detect targets in a multi-receive path environment, it is necessary to accurately separate multiple signal components in the range-velocity domain space.

[0152] At the same time, multiple targets can be separated by angle estimation. The angular resolution performance is related to the number of antennas and the antenna spacing, however, due to hardware limitations, the number of antennas and the antenna spacing are difficult to increase.

[0153] Furthermore, the velocity resolution for separating targets in the range-velocity domain can be improved.

[0154] However, as shown in Equation 2, since the recognition speed difference Δv is related to the duration of the chirp signal, it is difficult to change the recognition speed difference.

[0155] Therefore, in adverse driving conditions with stationary obstacles such as guardrails, soundproof walls, tunnels, etc., it is necessary to accurately distinguish targets by reducing the recognition distance difference Δv or increasing the distance resolution 1 / Δv.

[0156] Meanwhile, the distance resolution or range resolution is related to the frequency bandwidth of the radar signal (ie, the scanning frequency bandwidth of the chirp signal), and if the bandwidth BW increases, the distance resolution is improved according to Equation 1.

[0157] However, if the frequency bandwidth BW of the radar signal increases, the maximum detection distance r max The problem is reduced by the following equation 3.

[0158] [Equation 3]

[0159]

[0160] That is, if the frequency bandwidth BW is increased in order to improve the distance resolution (1 / Δr), the maximum detection distance r max It also decreases together with the recognition distance difference Δr.

[0161] In other words, as the frequency bandwidth BW increases, the distance resolution increases, so that an accurate horizontal position can be detected. However, since the maximum detection distance decreases, only a target in a narrow detection area can be detected.

[0162] Therefore, the radar apparatus according to the present embodiment may set a plurality of band modes divided by radar band values ​​or band ranges, and the mode selection unit 400 may determine one of the plurality of band modes as a selection mode based on the detection target distance and the maximum detection distance.

[0163] Specifically, each band mode is set by matching maximum detection distance information corresponding to a corresponding frequency band, and the mode selection unit 400 may determine a band mode having a maximum frequency band among band modes having a maximum detection distance greater than a distance to a detection target as a selection mode.

[0164] The radar device detects the object by using the radar signal in the frequency band corresponding to the determined selection mode during the next scanning operation.

[0165] That is, when operating in the operating frequency band of the selection mode determined by the mode selection unit 400, the distance resolution of the object at the corresponding target distance can be maximized.

[0166] In the radar device according to the present embodiment, under a specific driving condition, by dynamically determining the band mode associated with the maximum detection distance according to the distance to the target, the distance resolution of the radar device can be optimized.

[0167] Figure 8 shows an example of a plurality of frequency band mode setting information according to an embodiment of the present disclosure, Fig. 9 The change in detection performance of a target according to a dynamic pattern change according to an embodiment of the present disclosure is shown.

[0168] Reference Figure 8 In the radar device according to the present embodiment, a plurality of frequency band modes are set, and in each frequency band mode, a corresponding operating frequency bandwidth value BW is matched. i and the corresponding recognition distance difference (Δri or distance resolution) and the maximum detection distance r i,max .

[0169] The frequency band mode information may be preset in the form of a lookup table and stored in a memory or the like.

[0170] exist Figure 8 In FIG. 1 , it is shown that the frequency band mode information includes N modes, and in each mode i, the corresponding frequency bandwidth BW is matched. i (i=1, 2, ..., N), the corresponding identification distance difference Δri and the maximum detection distance (r i,max ).

[0171] In this case, it is assumed that the lower the mode number i is, the larger the frequency bandwidth BW is.

[0172] That is, in Figure 8 In the table, BW1>BW2>…>BW N , and according to the above equations 1 and 3, it can be established that r 1,max <r 2,max <… <r N,max Here, r N,max It can be set based on the maximum detection distance that the radar can detect, which is the capability of the radar device.

[0173] That is, as the mode number i decreases, the distance resolution (1 / Δri) also increases, but the maximum detection distance (r i,max ) is reduced.

[0174] In this state, the mode selection unit 400 can set the maximum detection distance (r i,max ) is greater than the target distance R of the detection target and has the maximum operating frequency bandwidth BW in one or more frequency band modes i The frequency band mode is determined as the selection mode.

[0175] For example, if the distance R to the target is greater than the second maximum detection distance (r 2,max ) and is less than the third maximum detection distance (r 3,max ), the mode selection unit 400 may determine the third mode with the third frequency bandwidth BW3 as the selected mode.

[0176] In a subsequent scanning or operation cycle, the radar device performs target detection in the determined third frequency bandwidth BW3 of the third mode.

[0177] Therefore, the radar device can have the maximum distance resolution within the detection range capable of detecting the corresponding target, and therefore, can accurately separate the target or accurately acquire the horizontal position information of the target as described above.

[0178] In this case, the number N of frequency band modes and the frequency bandwidth BW of each frequency band mode may be preset. i .

[0179] Fig. 9 The left figure shows the range-speed domain information of the target when working in the sixth frequency bandwidth BW6 corresponding to the sixth mode, and the right figure shows the range-speed domain information of the target when working in the third frequency bandwidth BW3 corresponding to the third mode according to the above mode selection.

[0180] As shown in the left figure, as a result of identifying targets in the sixth frequency bandwidth BW6 having a relatively small bandwidth, the range resolution is low, so that the first target T1 and the second target T2 may overlap and map in the range-speed domain area, making it difficult to separate the targets.

[0181] However, according to the mode selection of this embodiment, as a result of identifying targets in the third frequency bandwidth BW3 having a large bandwidth, as shown in the right figure, the distance resolution can be increased, so that the first target T1 and the second target T2 can be respectively identified in the range-speed domain area.

[0182] To this end, the transmission / reception unit 200 according to the present embodiment may receive information about the selection mode from the mode selection unit 400 and transmit a transmission signal in an operating frequency band corresponding to the selection mode in a subsequent scanning operation.

[0183] Furthermore, the signal processing unit 300 of the radar device according to the present embodiment may determine whether the target is a single target or multiple targets based on the range-speed information calculated according to the selection mode.

[0184] Meanwhile, the transmitting / receiving unit 200 , the signal processing unit 300 , the mode selecting unit 400 , and the situation determining unit 500 included in the radar device according to the present embodiment as described above may be implemented as a module in a vehicle radar control device or ECU.

[0185] Such a radar control device or ECU may include a processor, a storage device such as a memory, and a computer program capable of performing specific functions. In addition, the above-mentioned transmitting / receiving unit 200, the signal processing unit 300, the mode selection unit 400, and the condition determination unit 500 may be implemented as software modules capable of performing each corresponding function.

[0186] That is, the transmission / reception unit 200, the signal processing unit 300, the mode selection unit 400 and the condition determination unit 500 according to the present embodiment can be implemented as corresponding software modules and stored in the memory. In addition, each software module can be executed at a specific timing in a processing unit such as an ECU.

[0187] Fig.10 : is a flowchart showing the overall flow of a control method of a radar device according to an embodiment of the present disclosure.

[0188] Reference Fig.10 According to an embodiment, a control method of a radar device may include: transmitting a transmission signal in an operating frequency band according to a selection mode among a plurality of frequency band modes through a transmission antenna, and receiving a reception signal reflected from an object through a reception antenna (S1010); processing a reception signal received from the reception antenna to acquire target information (S1020); dynamically determining a selection mode from one of a plurality of frequency band modes based on at least one of a target distance to a target acquired in processing the reception signal and a maximum detection distance of each frequency band (S1040); and transmitting the transmission signal in an operating frequency band corresponding to the selection mode during a subsequent scanning operation (S1050).

[0189] In addition, the control method of the radar device according to the embodiment may also include: determining the driving condition of the vehicle based on the obtained information about the stationary obstacles around the vehicle; and if the driving condition of the vehicle corresponds to a specific driving condition, performing dynamic determination of the selection mode (S1030).

[0190] In this case, the specific driving condition may include a condition in which at least one of a guardrail, a soundproof wall, a tunnel, and an overpass exists around the vehicle. Information about stationary obstacles around the vehicle can be obtained from target information obtained from a signal processor or from other sensor information obtained from an additional vehicle detection sensor.

[0191] In addition, in step S1050, each of the plurality of band modes may be defined by a unique operating frequency band and a maximum detection distance corresponding to the unique operating frequency band. When the selection mode is dynamically determined, the selection mode may be determined by a band mode having a maximum operating frequency band among one or more band modes having a maximum detection distance greater than a target distance.

[0192] In the assumption that Figure 8 In the case where the frequency band information is set as shown, the determination of the selection mode S1050 can be performed using the following algorithm (software source code).

[0193]

[0194] According to the above algorithm, the mode number is increased from 1 to 1, and in the corresponding mode, the distance to the target r is set CIPV The value obtained by multiplying the specific gain by 1.2 is equal to the maximum detection distance r n,max For comparison, if the maximum detection distance r n,max Greater than the distance r from the target CIPV The value obtained by multiplying the gain selects the corresponding mode as the selection mode.

[0195] In this case, the gain is used to set the allowable range to ensure target detection, and the gain is described as 1.2 in the above algorithm, but is not limited to this, and any value greater than 1.0 is possible.

[0196] Fig.11 is a flowchart of a signal processing method provided by a radar device according to an embodiment of the present disclosure.

[0197] Fig.11 is a flowchart showing a signal processing process after receiving a reflected signal from a target. The radar device may buffer the received data obtained in the data acquisition completion step (S1110) into a unit sample size processable per cycle (S1120), and then perform frequency conversion (S1130).

[0198] Thereafter, CFAR (Constant False Alarm Rate) calculation is performed based on the frequency converted received data (S1140), and vertical / horizontal information, speed information, and distance information of the target are extracted (S1150). The frequency conversion in the frequency conversion step S1130 may use Fourier transform (FFT) such as Fast Fourier Transform.

[0199] Fig.12 The difference in signal waveform and frequency band when the radar device according to the embodiment of the present disclosure switches from the first mode to the second mode is shown.

[0200] As in the above-described embodiment, it is assumed that the radar apparatus operates in the sixth frequency bandwidth BW6 corresponding to the sixth mode and then operates in the third frequency bandwidth BW3 corresponding to the third mode through the mode selection operation according to the present embodiment.

[0201] like Fig.12 As shown, a first transmission signal in the sixth mode before the mode change is transmitted in the sixth frequency bandwidth BW6, and a second transmission signal after the mode change to the third mode is transmitted in the third frequency bandwidth BW3, which has a frequency band twice as large as BW6.

[0202] In this case, it is assumed that the number L of chirp signals included in one detection period T before and after the mode change, that is, the chirp duration remains the same (L=4).

[0203] However, in order to improve the angular resolution, the number L of chirp signals included in one detection period T may also be changed before and after the mode change.

[0204] For example, in the sixth mode before the mode change, a so-called slow chirp transmission signal having a large width waveform may be used.

[0205] Meanwhile, in the third mode after the mode change, a signal may be transmitted using a so-called fast chirp having a small width waveform.

[0206] Therefore, a first number of signal waveforms (ie, chirps) included in one detection period T before the mode change or periods in the sixth mode may be smaller than a second number of signal waveforms included in one detection period T in the third mode after the mode change.

[0207] Meanwhile, some of the sixth frequency bandwidth before the mode change and the third frequency bandwidth after the mode change may partially overlap or may be completely different from each other.

[0208] Generally speaking, a fast chirp method in which a plurality of signal waveforms are transmitted in one detection cycle can increase the amount of transmitted data, but can improve detection performance, and in particular, can ensure a desired degree of resolution with a low output.

[0209] As described above, according to the present embodiment, by dynamically changing the frequency bandwidth associated with the maximum detection distance according to the distance to the target under a specific driving condition, the distance resolution of the radar device can be dynamically optimized.

[0210] The antenna unit used in the radar apparatus according to the present embodiment is not limited to the above-described structure.

[0211] That is, another structure may be used in which the antenna unit according to the present embodiment includes one or more transmission antennas for transmitting the transmission signal and one or more reception antennas for receiving the reception signal reflected from the target.

[0212] In addition, the radar apparatus according to the present embodiment may employ a signal transmission and reception technology based on a multi-dimensional antenna array and multiple-input multiple-output (MIMO) in order to form a virtual antenna aperture that is larger than an actual antenna aperture.

[0213] For example, a two-dimensional antenna array can be used to achieve accuracy and higher resolution relative to vertical and / or horizontal angles. In the case of using a two-dimensional radar antenna array, signals are sent and received by two separate horizontal and vertical scans (time multiplexing), and MIMO can be used separately from the horizontal and vertical scans (time multiplexing) of the two-dimensional antenna array.

[0214] More specifically, a radar device according to one or more embodiments may include a two-dimensional antenna array, which includes a transmitting antenna component and a receiving antenna component, wherein the transmitting antenna component includes a total of 12 transmitting antennas Tx, and the receiving antenna component includes a total of 16 receiving antennas Rx; as a result, a total of 192 virtual receiving antennas can be arranged.

[0215] Furthermore, in another embodiment, when the antenna assembly of the radar sensor includes a two-dimensional antenna array, each antenna patch may be arranged in a rhombus or oblique square shape; therefore, unnecessary side lobes may be reduced.

[0216] Alternatively, the two-dimensional antenna device may include a V-shaped antenna array in which a plurality of radiation patches are arranged in a V shape, more specifically, two V-shaped antenna arrays. In this case, a single feed is performed on the vertex of each V-shaped antenna array.

[0217] Alternatively, the two-dimensional antenna arrangement may include an X-shaped antenna array, wherein a plurality of radiating patches are arranged in an X shape, more specifically, two X-shaped antenna arrays. In this case, a single feed is made to the center of each X-shaped antenna array.

[0218] Furthermore, the radar apparatus according to one or more embodiments may employ a MIMO antenna system to achieve accuracy and higher resolution with respect to vertical and / or horizontal angles.

[0219] More specifically, in a MIMO system, each transmit antenna can transmit a signal having a waveform independent of each other. That is, each transmit antenna can transmit a signal having a waveform independent of other transmit antennas, and then each receive antenna can determine from which transmit antenna the signal received from the object is transmitted due to the use of independent waveforms for each transmit antenna.

[0220] In addition, the radar device according to one or more embodiments may include a radar housing in which a substrate and a circuit provided with an antenna assembly are accommodated, and a radome is used as a shell of the radar housing. The radome may be formed of a material capable of reducing the attenuation of transmitted and received radar signals, and constitutes the front bumper or rear bumper, grille or side body of the vehicle, or the outer surface of one or more parts of the vehicle.

[0221] That is, the radome of the radar device can be set inside the bumper, grille or body of the vehicle, or set as a part of a component constituting the outer surface of the vehicle, such as a part of the bumper, grille or body. Therefore, the radome can improve the aesthetics of the vehicle and provide convenience for installing the radar sensor.

[0222] A radar sensor or radar device / system according to the present disclosure may include one or more of a front detection radar sensor installed at the front of a vehicle, a rear detection radar sensor installed at the rear of a vehicle, and a side or side rear detection radar sensor installed at the side of a vehicle, which may constitute at least one radar sensor subsystem.

[0223] The radar sensor or radar device / system can process data by analyzing the transmitted signal and the received signal, and thus extract information about the object. To this end, the radar sensor or radar sensor device / system may include an electronic or control circuit ECU or a processor. Data transmission or signal communication from the radar sensor to the electronic or control circuit ECU or processor may use a communication link, such as a vehicle network bus, etc.

[0224] Fig.13 FIG. 2 shows a configuration of a vehicle radar system according to an embodiment of the present disclosure. Fig.13 According to an embodiment, a radar system 1000 may include: a transmitting antenna 1100 for transmitting a transmission signal in an operating frequency band according to a selection mode among a plurality of frequency band modes; a receiving antenna 1200 for receiving a reception signal reflected from a target; and a signal processing device 1300 for processing a reception signal received from the receiving antenna to acquire target information, and dynamically determining the selection mode from one of the plurality of frequency band modes based on at least one of a target distance to the target acquired in processing the reception signal and a maximum detection distance of each frequency band, and transmitting the transmission signal in the operating frequency band corresponding to the selection mode during a subsequent scanning operation.

[0225] The transmitting antenna 1100 and the receiving antenna 1200 are composed of multiple antennas. Specifically, the transmitting antenna 1100 and the receiving antenna 1200 can be composed of multiple transmitting antenna units for transmitting signals and multiple receiving antenna units for receiving signals reflected from an object. At this time, the transmitting antenna 1100 and the receiving antenna 1200 can be respectively composed of multiple antennas A arranged in a one-dimensional or two-dimensional array, and each antenna A can have a different directivity angle.

[0226] In addition, the transmission antenna 1100 may be divided into a short-range antenna for sensing a short range according to a sensing area and a long-range antenna for sensing a long range. The reception antenna 1200 may receive a signal without dividing a sensing area.

[0227] The signal processing device 1300 controls the transmission and reception of signals of the transmission antenna 1100 and the reception antenna 1200. The signal processing device 1300 may control the signal transmitted from the transmission antenna 1100, and may analyze the signal received at the reception antenna 1200 to calculate the distance to the object. In addition, the signal processing device 1300 may control the signal transmitted from the transmission antenna 1100, or may adjust the object detection area by selecting the antenna that transmits the signal. In the transmission and reception of such signals, beamforming technology may be applied.

[0228] In addition, the signal processing device 1300 may determine the driving condition of the vehicle based on the obtained information about the stationary obstacles around the vehicle, and if the driving condition of the vehicle corresponds to a specific driving condition, the dynamic determination of the selection mode may be activated. In addition, the signal processing device 1300 may determine the band mode with the maximum operating frequency band as the selection mode among one or more band modes whose maximum detection distance is greater than the target distance. Each band mode included in the plurality of band modes is defined by a unique operating frequency band and a maximum detection distance corresponding to the unique operating frequency band.

[0229] As described above, according to the embodiments of the present disclosure, if a specific driving condition is satisfied, the horizontal detection performance of the radar device can be dynamically changed by dynamically determining one of a plurality of frequency band modes based on the detected distance to a target.

[0230] It should be noted that although all or some of the configurations or elements included in the above one or more embodiments have been combined to constitute a single configuration or component or operate in a combined manner, the present disclosure is not necessarily limited to this. That is, within the scope of the purpose or spirit of the present disclosure, all or some of the configurations or elements included in one or more embodiments may be combined to constitute one or more configurations or components or operate in such a combined configuration or component. In addition, each configuration or element included in one or more embodiments may be implemented by an independent hardware configuration; however, some or all of the configurations or elements may be selectively combined and implemented by one or more computer programs having one or more program modules, which perform some or all functions from one or more combined hardware configurations. Those skilled in the art can easily generate codes or code segments constituting a computer program. When a computer program stored in a computer-readable medium is read and executed by a computer, an embodiment of the present disclosure can be implemented. The medium for storing a computer program may include, for example, a magnetic storage medium, an optical recording medium, and a carrier medium.

[0231] In addition, unless otherwise specified herein, the terms "including", "comprising", "consisting of", "having", etc. described herein mean that one or more other configurations or elements may also be included in the corresponding configuration or element. Unless otherwise defined herein, all terms (including technical and scientific terms) used herein have the same meaning as understood by those skilled in the art. Unless otherwise defined herein, generally used terms (such as those defined in dictionaries) should be interpreted as having the same meaning as in the context of the relevant technology and should not be interpreted as an ideal or overly formal meaning.

[0232] The above description is given to enable those skilled in the art to implement and use the technical ideas of the present disclosure, and 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, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present disclosure. The above description and accompanying drawings provide examples of the technical ideas of the present disclosure for illustrative purposes only. That is, the disclosed embodiments are intended to illustrate the scope of the technical ideas of the present disclosure. Therefore, the scope of the present disclosure is not limited to the embodiments shown, but is in accordance with the widest scope consistent with the claims. The scope of protection of the present disclosure should be interpreted based on the attached claims, and all technical ideas within the scope of their equivalents should be interpreted as included within the scope of the present disclosure.

[0233] CROSS-REFERENCE TO RELATED APPLICATIONS

[0234] This application claims priority to Korean Patent Application No. 10-2020-0055149, filed on May 8, 2020, which is hereby incorporated by reference for all purposes as if fully set forth herein.

Claims

1. A vehicle radar device, comprising: an antenna unit including a transmission antenna for transmitting a transmission signal around the vehicle and a reception antenna for receiving a reception signal reflected from a target; a transceiver controlled to transmit the transmission signal in an operating frequency band according to a selection mode among a plurality of frequency band modes through the transmission antenna, and the transceiver controlled to receive the reception signal through the reception antenna; a signal processor, the signal processor processing the reception signal received from the reception antenna to obtain target information; as well as a mode selector that dynamically determines one of the plurality of frequency band modes as the selection mode based on at least one of a target distance to a target and a maximum detection distance of each frequency band acquired from the signal processor, Each of the plurality of frequency band modes is defined by a unique operating frequency band and a maximum detection distance corresponding to the unique operating frequency band. wherein the mode selector determines the frequency band mode having the largest operating frequency band among the one or more frequency band modes whose maximum detection distance is greater than the target distance as the selected mode, and The mode selector compares a value obtained by multiplying the target distance by a preset gain with the maximum detection distance, and determines a band mode in which the maximum detection distance increases as the selection mode.

2. The vehicle radar device according to claim 1, further comprising a situation determiner that determines a driving condition of the vehicle based on the obtained information about stationary obstacles around the vehicle, and activates the mode selector if the driving condition of the vehicle corresponds to a specific driving condition.

3. The vehicle radar device according to claim 2, wherein: The specific driving condition includes a condition in which at least one of a guardrail, a soundproof wall, a tunnel, and an overpass exists around the vehicle.

4. The vehicle radar device according to claim 1, wherein: The signal processor performs a fast-time first Fourier transform, i.e., a first FFT, on the received signal to obtain a time component according to the distance, and performs a slow-time second Fourier transform, i.e., a second FFT, and compresses the signal existing at each distance according to the speed to calculate the range-speed information of the target.

5. The vehicle radar device according to claim 4, wherein: The signal processor determines whether the target is a single target or multiple targets based on the range-speed information calculated according to the selection mode.

6. The vehicle radar device according to claim 1, wherein: The transceiver receives information about the selection mode from the mode selector, and transmits a transmission signal in an operating frequency band corresponding to the selection mode during a subsequent scanning operation.

7. The vehicle radar device according to claim 1, wherein: The range resolution of an object at the target distance is maximized according to the operating frequency band of the selected mode determined by the mode selector.

8. A control method for a vehicle radar device, the control method comprising: transmitting a transmission signal in an operating frequency band according to a selected mode among a plurality of frequency band modes through a transmission antenna, and receiving a reception signal reflected from an object through a reception antenna; processing the received signal received from the receiving antenna to obtain target information; dynamically determining the selection mode from one of the plurality of frequency band modes based on at least one of a target distance to a target and a maximum detection distance of each frequency band acquired in processing the received signal; and transmitting the transmit signal in an operating frequency band corresponding to the selection mode during a subsequent scanning operation, Each of the plurality of frequency band modes is defined by a unique operating frequency band and a maximum detection distance corresponding to the unique operating frequency band. The dynamically determining the selection mode comprises: determining a frequency band mode having a maximum operating frequency band as the selection mode among one or more frequency band modes whose maximum detection distance is greater than the target distance, and The dynamically determining the selection mode includes comparing a value obtained by multiplying the target distance by a preset gain with the maximum detection distance, and determining a frequency band mode in which the maximum detection distance increases as the selection mode.

9. The control method according to claim 8, further comprising: A driving condition of the vehicle is determined based on the obtained information about stationary obstacles around the vehicle, and the dynamic determination of the selection mode is activated if the driving condition of the vehicle corresponds to a specific driving condition.

10. The control method according to claim 9, wherein: The specific driving condition includes a condition in which at least one of a guardrail, a soundproof wall, a tunnel, and an overpass exists around the vehicle.

11. The control method according to claim 8, wherein: Processing the received signal includes: performing a fast time first Fourier transform, i.e., a first FFT, on the received signal to obtain a time component according to the distance; and performing a slow time second Fourier transform, i.e., a second FFT, and compressing the signal existing at each distance according to the speed to calculate the range-speed information of the target.

12. The control method according to claim 11, wherein: Processing the received signal includes determining whether the target is a single target or multiple targets based on the range-speed information calculated according to the selection mode.

13. The control method according to claim 8, wherein: According to the operating frequency band of the selection mode determined in dynamically determining the selection mode, a distance resolution of an object at the target distance is maximized.

14. A vehicle radar system, the vehicle radar system comprising: a transmitting antenna, the transmitting antenna being used to transmit a transmit signal in an operating frequency band according to a selected mode among a plurality of frequency band modes; A receiving antenna, the receiving antenna being used to receive a receiving signal reflected from a target; as well as a signal processing device that processes the reception signal received from the reception antenna to acquire target information, and dynamically determines the selection mode from one of the plurality of frequency band modes based on at least one of a target distance to a target and a maximum detection distance of each frequency band acquired in processing the reception signal, and transmits the transmission signal in an operating frequency band corresponding to the selection mode during a subsequent scanning operation, Each of the plurality of frequency band modes is defined by a unique operating frequency band and a maximum detection distance corresponding to the unique operating frequency band. wherein the signal processing device determines the frequency band mode having the largest operating frequency band as the selection mode among the one or more frequency band modes whose maximum detection distance is greater than the target distance, and The signal processing device compares a value obtained by multiplying the target distance by a preset gain with the maximum detection distance, and determines a band mode in which the maximum detection distance increases as the selection mode.

15. The vehicle radar system according to claim 14, wherein: The signal processing device determines a driving condition of the vehicle based on the obtained information about stationary obstacles around the vehicle, and if the driving condition of the vehicle corresponds to a specific driving condition, the signal processing device activates the dynamic determination of the selection mode.

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