Vehicle radar device and system thereof

A vehicle radar device includes a radar control unit, a first antenna array, a second antenna array, a first circuit board and a second circuit board. The first antenna array is communicatively connected to the radar control unit. The first antenna array includes a plurality of first transmitting elements and a plurality of first receiving elements. The second antenna array is communicatively connected to the radar control unit. The second antenna array includes a plurality of second transmitting elements and a plurality of second receiving elements. The first antenna array is a plurality of circuit board antennas and disposed on the first circuit board. The second antenna array is a plurality of circuit board antennas and disposed on the second circuit board.

RELATED APPLICATIONS

This application claims priority to Taiwan Application Serial Number 108104305, filed Feb. 1, 2019, which is herein incorporated by reference.

BACKGROUND

Technical Field

The present disclosure relates to a vehicle radar device and a vehicle radar system. More particularly, the present disclosure relates to a vehicle radar device and a vehicle radar system both including two antenna arrays.

Description of Related Art

With the rapid developments of advanced driver assistance system (ADAS) and autopilot technology, vehicles are often required to be equipped with a large number of detection devices or sensing devices to achieve the relevant functions, and thereby the application requirements of the vehicle radar devices are more and more. However, from the vehicle manufacturer's point of view, the configuration of the large number of detection devices is result in increasing the complexity of electronic system design and whole vehicle assembling. From the consumers point of view, if the large number of detection devices of aftermarket (AM) types are equipped, it would raise the complexity of the human interface or the connection interface, and the various functions from the multiple detection devices cannot be effectively separated or can cause interference issues.

Give the above, there is an urgent need for an integrated solution of a vehicle detection device or a vehicle radar device, which is featured with effectively reducing device number and complexity, in today's market.

SUMMARY

According to one aspect of the present disclosure, a vehicle radar device includes a radar control unit, a first antenna array, a second antenna array, a first circuit board and a second circuit board. The first antenna array is communicatively connected to the radar control unit. The first antenna array includes a plurality of first transmitting elements and a plurality of first receiving elements. The second antenna array is communicatively connected to the radar control unit. The second antenna array includes a plurality of second transmitting elements and a plurality of second receiving elements. The first antenna array is a plurality of circuit board antennas and disposed on the first circuit board. The second antenna array is a plurality of circuit board antennas and disposed on the second circuit board. When an angle between the first circuit board and the second circuit board is P12, the following condition is satisfied: 60 degrees≤P12<180 degrees.

According to another aspect of the present disclosure, a vehicle radar system is disposed in a vehicle and includes at least one vehicle radar device. The vehicle radar device includes a radar control unit, a first transceiver unit and a second transceiver unit. The first transceiver unit is communicatively connected to the radar control unit and includes a first antenna array, which includes a plurality of first transmitting elements and a plurality of first receiving elements. The second transceiver unit is communicatively connected to the radar control unit and includes a second antenna array, which includes a plurality of second transmitting elements and a plurality of second receiving elements. When an angle between a centerline of a horizontal main lobe of the first transmitting elements and a centerline of a horizontal main lobe of the second transmitting elements is T12, and an angle between a centerline of a horizontal main lobe of the first receiving elements and a centerline of a horizontal main lobe of the second receiving elements is R12, the following conditions are satisfied: 0 degrees<T12≤90 degrees; and 0 degrees<R12≤90 degrees.

According to another aspect of the present disclosure, a vehicle radar system is disposed in a vehicle and includes at least one vehicle radar device, which is disposed at one of four corners of the vehicle. The vehicle radar device includes a radar control unit, a first antenna array, a second antenna array, a first circuit board and a second circuit board. The first antenna array is communicatively connected to the radar control unit. The second antenna array is communicatively connected to the radar control unit. The first circuit board is vertical to a horizontal direction of the vehicle. The first antenna array is a plurality of circuit board antennas and disposed on the first circuit board. The second circuit board is vertical to the horizontal direction of the vehicle. The second antenna array is a plurality of circuit board antennas and disposed on the second circuit board. When an angle between the first circuit board and the second circuit board is P12, the following condition is satisfied: 90 degrees≤P12<180 degrees.

DETAILED DESCRIPTION

The embodiment will be described with the drawings. For clarity, some practical details will be described below. However, it should be noted that the present disclosure should not be limited by the practical details, that is, in some embodiments, the practical details is unnecessary. In addition, for simplifying the drawings, some conventional structures and elements will be simply illustrated, and repeated elements may be represented by the same labels.

FIG. 1Ais a schematic view of a vehicle radar device100according to the 1st embodiment of the present disclosure,FIG. 1Bis another schematic view of the vehicle radar device100according to the 1st embodiment,FIG. 1Cis a cross-sectional view along line1C-1C ofFIG. 1B, andFIG. 1Dis an exploded view of the vehicle radar device100according to the 1st embodiment. InFIG. 1AtoFIG. 1D, the vehicle radar device100includes a radar control unit130, a first antenna array151, a second antenna array152, a first circuit board181and a second circuit board182.

The first antenna array151is communicatively connected to the radar control unit130. The first antenna array151includes a plurality of first transmitting elements161and a plurality of first receiving elements171. That is, the first transmitting elements161are first transmitting radiating elements, and the first receiving elements171are first receiving radiating elements. The first antenna array151is a plurality of circuit board antennas and disposed on the first circuit board181. The second antenna array152is communicatively connected to the radar control unit130. The second antenna array152includes a plurality of second transmitting elements162and a plurality of second receiving elements172. That is, the second transmitting elements162are second transmitting radiating elements, and the second receiving elements172are second receiving radiating elements. The second antenna array152is a plurality of circuit board antennas and disposed on the second circuit board182. When an angle between the first circuit board181and the second circuit board182is P12, the following condition is satisfied: 60 degrees≤P12<180 degrees. Accordingly, the first antenna array151and the second antenna array152, which are two non-coplanar antenna arrays, are advantageous in providing detections with various directions and various antenna radiation patterns in accordance with various application requirements. Furthermore, the following condition may be satisfied: 90 degrees≤P12<180 degrees. Moreover, the following condition may be satisfied: 120 degrees≤P12≤150 degrees. In the 1st embodiment, the angle P12between the first circuit board181and the second circuit board182is 135 degrees.

InFIG. 1C, the vehicle radar device100may further include a third circuit board183. The radar control unit130is disposed on the third circuit board183. Only one of the first circuit board181and the second circuit board182(specifically only the second circuit board182in the 1st embodiment) is parallel to the third circuit board183. Accordingly, it is beneficial to the vehicle radar device100to achieve a compact size. In an embodiment according to the present disclosure, each of a first circuit board, a second circuit board and a third circuit board may be a printed circuit board (PCB), a flexible printed circuit board, or a ceramic circuit board, but not limited thereto.

An operating frequency of the first antenna array151and an operating frequency of the second antenna array152may be both greater than 10 GHz. Furthermore, the operating frequency of the first antenna array151and the operating frequency of the second antenna array152may be both greater than 10 GHz and smaller than 300 GHz. Moreover, the operating frequency of the first antenna array151and the operating frequency of the second antenna array152may be both 24 GHz+/−5 GHz, 77 GHz+/−5 GHz, or 79 GHz+/−5 GHz. Each of the first transmitting elements161, each of the first receiving elements171, each of the second transmitting elements162and each of the second receiving elements172is a microstrip antenna and has a length smaller than 40 mm. The aforementioned microstrip antenna may be in a microstrip (strip or rectangular) shape, in a patch shape, in a comb shape, or a microstrip slot, but not limited thereto. Furthermore, each of the first transmitting elements161, each of the first receiving elements171, each of the second transmitting elements162and each of the second receiving elements172is the microstrip antenna and may have the length smaller than30mm. Moreover, each of the first transmitting elements161, each of the first receiving elements171, each of the second transmitting elements162and each of the second receiving elements172is the microstrip antenna and may have the length smaller than 20 mm and greater than 0.2 mm. Therefore, the vehicle radar device100being a millimeter wave radar device is advantageous in reducing the number of the vehicle radar device100and maintaining the same applications and functions. The second transmitting elements162may be a plurality of second narrow-angle transmitting elements160and a plurality of second wide-angle transmitting elements166, and the radar control unit130is for switching the second narrow-angle transmitting elements160or the second wide-angle transmitting elements166to operate. The second receiving elements172may be a plurality of second narrow-angle receiving elements170and a plurality of second wide-angle receiving elements177, and the radar control unit130is for switching the second narrow-angle receiving elements170or the second wide-angle receiving elements177to operate. Therefore, it is beneficial to enlarge the detection range of the second antenna array152. In addition, a transmitting circuit communicatively connected to the second narrow-angle transmitting elements160and a transmitting circuit communicatively connected to the second wide-angle transmitting elements166may be separated or the same one to operate by switching. A receiving circuit communicatively connected to the second narrow-angle receiving elements170and a receiving circuit communicatively connected to the second wide-angle receiving elements177may be separated or the same one to operate by switching.

Specifically, the operating frequency of the first antenna array151and the operating frequency of the second antenna array152are both about 77 GHz or 79 GHz. Relative permittivity at the operating frequency of the first circuit board181, the second circuit board182and the third circuit board183may be in a range of 2.0 to 4.3. Furthermore, the relative permittivity at the operating frequency of the first circuit board181, the second circuit board182and the third circuit board183may be in a range of 2.2 to 3.8. Moreover, a dimension of the first circuit board181may be at least 19 mm×20 mm×1.4 mm (thickness), and a dimension of the second circuit board182may be at least 30 mm×20 mm×1.4 mm (thickness). The first circuit board181and the second circuit board182respectively include a plurality of through holes191and192, which are properly configured and have electrical conductivity. The first circuit board181, the second circuit board182and the third circuit board183may be communicatively connected by flexible flat cables (FFC), with the numbers of the conductive wires and the space sizes according to the demands. The flexible flat cables may be made of thermoplastic organic LCP (Liquid Crystal Polymers) materials to act as high frequency and high speed flexible circuit boards with high reliability. The LCP materials featured with superior electrical properties are advantageous in being applicable to millimeter wave, and the LCP materials featured with small coefficient of thermal expansion can act as ideal package materials for high frequency and high speed product. In addition, the first circuit board181, the second circuit board182and the third circuit board183are all disposed in a housing140, which includes a connector144.

InFIG. 1AandFIG. 1B, each of the first transmitting elements161is a rectangular microstrip slot antenna, i.e. a radiating slot, which is formed by a slot of a conductive layer on one surface of the first circuit board181and has a dimension about 3.2 mm (length)×0.5 mm (width). The first transmitting elements161are arranged along a width direction. For example, the first transmitting elements161may be arranged as a slot array antenna of an array of 1×16. A dimension of the slot array antenna formed by the sixteen first transmitting elements161is about 3.2 mm×17.6 mm. Based on demands, one of the first transmitting elements161may be communicatively connected to another thereof by at least one of a series connection and a parallel connection, and the first transmitting elements161have at least one feeding port. Each of the first receiving elements171is a rectangular microstrip slot antenna and has a dimension about 3.2 mm (length)×0.5 mm (width). The first receiving elements171are arranged along a width direction. Based on demands, one of the first receiving elements171may be communicatively connected to another thereof by at least one of a series connection and a parallel connection, and the first receiving elements171have at least one feeding port. Each of the second narrow-angle transmitting elements160is a rectangular microstrip slot antenna and has a dimension about 3.2 mm (length)×0.5 mm (width). The second narrow-angle transmitting elements160are arranged along a width direction. Based on demands, one of the second narrow-angle transmitting elements160may be communicatively connected to another thereof by at least one of a series connection and a parallel connection, and the second narrow-angle transmitting elements160have at least one feeding port. Each of the second wide-angle transmitting elements166is a rectangular microstrip slot antenna and has a dimension about 3.2 mm (length)×0.5 mm (width). The second wide-angle transmitting elements166are arranged along a width direction. Based on demands, one of the second wide-angle transmitting elements166may be communicatively connected to another thereof by at least one of a series connection and a parallel connection, and the second wide-angle transmitting elements166have at least one feeding port. Each of the second narrow-angle receiving elements170is a rectangular microstrip slot antenna and has a dimension about 3.2 mm (length)×0.5 mm (width). The second narrow-angle receiving elements170are arranged along a width direction. Based on demands, one of the second narrow-angle receiving elements170may be communicatively connected to another thereof by at least one of a series connection and a parallel connection, and the second narrow-angle receiving elements170have at least one feeding port. Each of the second wide-angle receiving elements177is a rectangular microstrip slot antenna and has a dimension about 3.2 mm (length)×0.5 mm (width). The second wide-angle receiving elements177are arranged along a width direction. Based on demands, one of the second wide-angle receiving elements177may be communicatively connected to another thereof by at least one of a series connection and a parallel connection, and the second wide-angle receiving elements177have at least one feeding port. Furthermore, the series connections, the parallel connections and the feeding ports recited in this paragraph can be configured according to demands and thereby are not specifically shown in the drawings.

In an embodiment according to the present disclosure (not shown in drawings), a dimension of the first circuit board and a dimension of the second circuit board may be greater than the dimensions thereof recited in the aforementioned 1st embodiment. For example, the dimension of the first circuit board may be 38 mm×40 mm×1.4 mm (thickness), the dimension of the second circuit board may be 60 mm×40 mm×1.4 mm (thickness), and a number of each of first transmitting elements, first receiving elements, second narrow-angle transmitting elements, second wide-angle transmitting elements, second narrow-angle receiving elements and second wide-angle receiving elements may be greater than the number thereof recited in the aforementioned 1st embodiment.

FIG. 2is a schematic view of a vehicle radar device200according to the 2nd embodiment of the present disclosure. InFIG. 2, the vehicle radar device200includes a radar control unit (not shown inFIG. 2), a first antenna array251, a second antenna array252, a first circuit board281and a second circuit board282. The first antenna array251is communicatively connected to the radar control unit. The first antenna array251includes a plurality of first transmitting elements261and a plurality of first receiving elements271. The first antenna array251is a plurality of circuit board antennas and disposed on the first circuit board281. The second antenna array252is communicatively connected to the radar control unit. The second antenna array252includes a plurality of second transmitting elements262and a plurality of second receiving elements272. The second transmitting elements262are a plurality of second narrow-angle transmitting elements260and a plurality of second wide-angle transmitting elements266. The second receiving elements272are a plurality of second narrow-angle receiving elements270and a plurality of second wide-angle receiving elements277. The second antenna array252is a plurality of circuit board antennas and disposed on the second circuit board282. An angle P12between the first circuit board281and the second circuit board282is 135 degrees. In addition, the first circuit board281and the second circuit board282respectively include a plurality of through holes291and292, which are properly configured and have electrical conductivity. The first circuit board281, the second circuit board282and the third circuit board (not shown in drawings) are all disposed in a housing240, which includes a connector244.

Specifically, regarding the vehicle radar device200of the 2nd embodiment, except the configurations of the first transmitting elements261, the first receiving elements271, the second narrow-angle transmitting elements260, the second wide-angle transmitting elements266, the second narrow-angle receiving elements270and the second wide-angle receiving elements277being different from the configurations recited in the aforementioned 1st embodiment, the other characteristics of the vehicle radar device200may be the same as the corresponding characteristics of the vehicle radar device100.

In the 2nd embodiment, each of the first transmitting elements261is a rectangular microstrip slot antenna and has a dimension about 3.2 mm (length)×0.5 mm (width). A number of the first transmitting elements261is sixteen, and the first transmitting elements261are arranged as an array of 2×8. Based on demands, one of the first transmitting elements261may be communicatively connected to another thereof by at least one of a series connection and a parallel connection, and the first transmitting elements261have at least one feeding port. Each of the first receiving elements271is a rectangular microstrip slot antenna and has a dimension about 3.2 mm (length)×0.5 mm (width). A number of the first receiving elements271is sixteen, and the first receiving elements271are arranged as an array of2x8. Based on demands, one of the first receiving elements271may be communicatively connected to another thereof by at least one of a series connection and a parallel connection, and the first receiving elements271have at least one feeding port. Each of the second narrow-angle transmitting elements260is a rectangular microstrip slot antenna and has a dimension about 3.2 mm (length)×0.5 mm (width). A number of the second narrow-angle transmitting elements260is sixteen, and the second narrow-angle transmitting elements260are arranged as an array of 4×4. Based on demands, one of the second narrow-angle transmitting elements260may be communicatively connected to another thereof by at least one of a series connection and a parallel connection, and the second narrow-angle transmitting elements260have at least one feeding port. Each of the second wide-angle transmitting elements266is a rectangular microstrip slot antenna and has a dimension about 3.2 mm (length)×0.5 mm (width). A number of the second wide-angle transmitting elements266is sixteen, and the second wide-angle transmitting elements266are arranged as an array of 4×4. Based on demands, one of the second wide-angle transmitting elements266may be communicatively connected to another thereof by at least one of a series connection and a parallel connection, and the second wide-angle transmitting elements266have at least one feeding port. Each of the second narrow-angle receiving elements270is a rectangular microstrip slot antenna and has a dimension about 3.2 mm (length)×0.5 mm (width). A number of the second narrow-angle receiving elements270is sixteen, and the second narrow-angle receiving elements270are arranged as an array of 4×4. Based on demands, one of the second narrow-angle receiving elements270may be communicatively connected to another thereof by at least one of a series connection and a parallel connection, and the second narrow-angle receiving elements270have at least one feeding port. Each of the second wide-angle receiving elements277is a rectangular microstrip slot antenna and has a dimension about 3.2 mm (length)×0.5 mm (width). A number of the second wide-angle receiving elements277is sixteen, and the second wide-angle receiving elements277are arranged as an array of4x4. Based on demands, one of the second wide-angle receiving elements277may be communicatively connected to another thereof by at least one of a series connection and a parallel connection, and the second wide-angle receiving elements277have at least one feeding port. Furthermore, the series connections, the parallel connections and the feeding ports recited in this paragraph can be configured according to demands and thereby are not specifically shown in the drawings.

FIG. 3is a schematic view of a vehicle radar device300according to the 3rd embodiment of the present disclosure. InFIG. 3, the vehicle radar device300includes a radar control unit (not shown in drawings), a first antenna array351, a second antenna array352, a first circuit board381and a second circuit board382. The first antenna array351is communicatively connected to the radar control unit. The first antenna array351includes a plurality of first transmitting elements361and a plurality of first receiving elements371. The first antenna array351is a plurality of circuit board antennas and disposed on the first circuit board381. The second antenna array352is communicatively connected to the radar control unit. The second antenna array352includes a plurality of second transmitting elements362and a plurality of second receiving elements372. The second transmitting elements362are a plurality of second narrow-angle transmitting elements360and a plurality of second wide-angle transmitting elements366. The second receiving elements372are a plurality of second narrow-angle receiving elements370and a plurality of second wide-angle receiving elements377. The second antenna array352is a plurality of circuit board antennas and disposed on the second circuit board382. An angle P12between the first circuit board381and the second circuit board382is 135 degrees. In addition, the first circuit board381, the second circuit board382and the third circuit board (not shown in drawings) are all disposed in a housing340, which includes a connector344.

Specifically, each of the first transmitting elements361, the first receiving elements371, the second narrow-angle transmitting elements360, the second wide-angle transmitting elements366, the second narrow-angle receiving elements370and the second wide-angle receiving elements377is a series-fed patch array (SFPA), and a configuration and at least one feeding port thereof can be configured according to demands and are not more specifically shown in the drawings. Furthermore, regarding the vehicle radar device300of the 3rd embodiment, except the antenna type of the first antenna array351, the antenna type of the second antenna array352, the dimension of the first circuit board381and the dimension of the second circuit board382being different from those recited in the aforementioned 1st embodiment, the other characteristics of the vehicle radar device300may be the same as the corresponding characteristics of the vehicle radar device100.

FIG. 4Ais a schematic view of a vehicle radar system4000according to the 4th embodiment of the present disclosure, which is disposed in a vehicle40.FIG. 4Bis a block diagram of the vehicle radar system4000according to the 4th embodiment disposed in the vehicle40.FIG. 4Cis a block diagram of the vehicle radar system4000according to the 4th embodiment. InFIG. 1AandFIG. 4AtoFIG. 4C, the vehicle radar system4000is disposed in the vehicle40and includes the vehicle radar device100recited in the aforementioned 1st embodiment. The vehicle radar device100includes the radar control unit130, a first transceiver unit141and a second transceiver unit142. The first transceiver unit141is communicatively connected to the radar control unit130and includes the first antenna array151, and thereby the first antenna array151is also communicatively connected to the radar control unit130. The second transceiver unit142is communicatively connected to the radar control unit130and includes the second antenna array152, and thereby the second antenna array152is also communicatively connected to the radar control unit130. In addition, it shall be realized that other vehicle radar device according to the present disclosure can be included in the vehicle radar system4000.

FIG. 4Dis a schematic view of a parameter R12according to the 4th embodiment.FIG. 4Eis a schematic view of a radiation pattern on a horizontal plane (orientated the same as a horizontal direction of the vehicle40) of the first receiving elements171according to the 4th embodiment.FIG. 4Fis a schematic view of a radiation pattern on a horizontal plane of the second receiving elements172(specifically the second wide-angle receiving elements177thereof) according to the 4th embodiment. Specifically, a schematic view of a parameter T12is similar toFIG. 4D. InFIG. 4DtoFIG. 4F, the first antenna array151may include the first transmitting elements161and the first receiving elements171. The second antenna array152may include the second transmitting elements162and the second receiving elements172. When an angle between a centerline of a horizontal main lobe (i.e. a main lobe on the horizontal plane) of the first transmitting elements161and a centerline of a horizontal main lobe of the second transmitting elements162is T12, and an angle between a centerline C1of a horizontal main lobe MLR1of the first receiving elements171and a centerline C2of a horizontal main lobe MLR2of the second receiving elements172is R12, the following conditions may be satisfied: 0 degrees<T12≤90 degrees; and 0 degrees<R12≤90 degrees. Accordingly, the vehicle radar system4000is advantageous in simultaneously providing detections in different directions and maintaining the individual detection accuracy by the first antenna array151and the second antenna array152. Furthermore, the following condition may be satisfied: 15 degrees≤R12≤75 degrees. Moreover, the following condition may be satisfied: 30 degrees≤R12≤60 degrees. In the 1st embodiment, the parameter T12is 45 degrees, and the parameter R12is 45 degrees.

Furthermore, inFIG. 1CandFIG. 4A, the vehicle radar device100may be disposed at one of four corners (i.e. a left-front corner48L, a right-front corner48R, a left-rear corner49L and a right-rear corner49R shown inFIG. 4A) of the vehicle40. Specifically, the vehicle radar device100is disposed at the left-rear corner49L as shown inFIG. 4A. The vehicle radar device100may further include the first circuit board181and the second circuit board182. The first circuit board181is vertical to the horizontal direction of the vehicle40. The first antenna array151is the circuit board antennas and disposed on the first circuit board181. The second circuit board182is vertical to the horizontal direction of the vehicle40. The second antenna array152is the circuit board antennas and disposed on the second circuit board182. When the angle between the first circuit board181and the second circuit board182is P12, the following condition may be satisfied: 60 degrees≤P12≤180 degrees. Accordingly, the first antenna array151and the second antenna array152are advantageous in respectively providing detections in accordance with various application requirements, reducing the cost of the vehicle radar system4000and simplifying the detection optimizing procedure. Furthermore, the following condition may be satisfied: 90 degrees≤P12≤180 degrees. Moreover, the following condition may be satisfied: 105 degrees≤P12≤165 degrees. In addition, the following condition may be satisfied: 120 degrees≤P12≤150 degrees.

InFIG. 4E, when a half power beam width (HPBW) of the horizontal main lobe MLR1of the first receiving elements171is RA1, which is defined by half power markers m1and m2, the following condition may be satisfied: 75 degrees≤RA1≤180 degrees. In the 4th embodiment, a value of the parameter RA1is 84 degrees. Therefore, a wider detection range can be provided by the first antenna array151.

InFIG. 4F, a half power beam width of the horizontal main lobe MLR2of the second wide-angle receiving elements177of the second receiving elements172is RAW2, which is defined by half power markers ml and m2. In the 4th embodiment, a value of the parameter RAW2is 118 degrees.

The vehicle radar device100may further include the third circuit board183. The radar control unit130is disposed on the third circuit board183. Only one of the first circuit board181and the second circuit board182(specifically only the second circuit board182in the 4th embodiment) is parallel to the third circuit board183. Accordingly, it is beneficial to the vehicle radar system4000to achieve a compact size. In an embodiment according to the present disclosure (not shown in drawings), it may be only the first circuit board of the first circuit board and the second circuit board parallel to the third circuit board.

Specifically, besides including the first transmitting elements161, a transmitting circuit of the first transceiver unit141may further include other elements (not shown in drawings), such as a local oscillator, a phase locked loop (PLL), a power amplifier and etc., which may be disposed on the first circuit board181or the third circuit board183. The local oscillator supporting a wider bandwidth is advantageous in increasing the distance resolution, due to the distance resolution of the vehicle radar system4000is determined by the signal bandwidth generated by the transmitting circuit. Furthermore, the phase locked loop is beneficial to the phase control of the local oscillator so as to minimize the phase noise of the local oscillator. Besides including the first receiving elements171, a receiving circuit of the first transceiver unit141may further include other elements (not shown in drawings), such as a low noise amplifier, an image rejection and clutter cancellation circuit portion and etc., which may be disposed on the first circuit board181or the third circuit board183. Configurations of a transmitting circuit and a receiving circuit of the second transceiver unit142may be different from but similar to those of the first transceiver unit141, and the elements of the second transceiver unit142may be disposed on the second circuit board182or the third circuit board183. Alternately, a transmitting circuit and a receiving circuit (except the first antenna array151and second antenna array152thereof, respectively) may be both switched to be used by the first transceiver unit141or the second transceiver unit142.

In addition, the first transceiver unit141and the second transceiver unit142are configured to generate FMCW (Frequency Modulated Continuous Wave) triangular waveform signals. After the first transceiver unit141and the second transceiver unit142receive a plurality of echo signals, the radar control unit130performs a FFT (Fast Fourier Transform) step to obtain a beat frequency and a Doppler shift data of a target object (or a target vehicle), and then estimates a distance, a speed and an angle information of the target object with respect to the vehicle radar device100according to the data. An algorithm configured in the radar control unit130includes the FFT, a beamforming and a CFAR (Constant False Alarm Rate) steps, wherein the FFT step is configured to provide the distance and the speed information, the beamforming step is configured to estimate the angle and a position information, and the CFAR step is configured to detect the target object while the clutter and other noise existing.

InFIG. 1BandFIG. 4A, the operating frequency of the first antenna array151and the operating frequency of the second antenna array152may be both greater than 10 GHz. Each of the first transmitting elements161, each of the first receiving elements171, each of the second transmitting elements162and each of the second receiving elements172is the microstrip antenna extending along the horizontal direction of the vehicle40and has the length smaller than 40 mm. Therefore, it is advantageous in reducing the number of the vehicle radar device100equipped in the vehicle radar system4000and maintaining the same applications and functions.

In an embodiment according to the present disclosure, the first transmitting elements, the first receiving elements, the second transmitting elements and the second receiving elements may be circuit board antennas, which may be microstrip antennas specifically, e.g. slots antenna, patch antennas, microstrip shape antennas or comb antennas extending along a horizontal direction or a vertical direction of a vehicle. Alternately, the first transmitting elements, the first receiving elements, the second transmitting elements and the second receiving elements may not be circuit board antennas, e.g. dish antennas. Moreover, types of the first transmitting elements, the first receiving elements, the second transmitting elements and the second receiving elements are not limited thereto, and the following conditions are satisfied: 0 degrees<T12≤90 degrees; and 0 degrees<R12≤90 degrees.

InFIG. 4A, the vehicle radar system4000includes two vehicle radar devices, i.e. vehicle radar devices100and100a,which are respectively disposed at the left-rear corner49L and the right-rear corner49R of the vehicle40, and located inside the bumper fascia. The first circuit board181included in the vehicle radar device100and a first circuit board181aincluded in the vehicle radar device100aface a left direction and a right direction of the vehicle40, respectively, and are disposed symmetrically relative to a longitudinal centerline y of the vehicle40. That is, first transceiver units141and141a,which are included in the vehicle radar devices100and100a,respectively, are configured to respectively detect a left environment and a right environment of the vehicle40, and also both detect a rear environment of the vehicle40. The second circuit board182included in the vehicle radar device100and a second circuit board182aincluded in the vehicle radar device100aboth face a rear direction of the vehicle40and are disposed symmetrically relative to the longitudinal centerline y of the vehicle40. That is, second transceiver units142and142a,which are included in the vehicle radar devices100and100a,respectively, are both configured to detect the rear environment of the vehicle40. Accordingly, the vehicle radar system4000can provide the detection information of the left direction, the right direction and the rear direction of the vehicle40so as to achieve the functions of BSD (Blind Spot Detection), LCA (Lane Change Assistance) and reverse detection of the vehicle40via a single device set (i.e. the vehicle radar devices100and100a).

Specifically, the vehicle radar device100adisposed at the right-rear corner49R of the vehicle40includes the radar control unit130a,the first transceiver unit141a,the second transceiver unit142a,the first circuit board181a,the second circuit board182aand the third circuit board183a.The first transceiver unit141ais communicatively connected to the radar control unit130aand includes a first antenna array151a.The second transceiver unit142ais communicatively connected to the radar control unit130aand includes a second antenna array152a.The first circuit board181ais vertical to the horizontal direction of the vehicle40. The first antenna array151ais a plurality of circuit board antennas and disposed on the first circuit board181a.The second circuit board182ais vertical to the horizontal direction of the vehicle40. The second antenna array152ais a plurality of circuit board antennas and disposed on the second circuit board182a.The radar control unit130ais disposed on the third circuit board183a.Only the second circuit board182aof the first circuit board181aand the second circuit board182ais parallel to the third circuit board183a.In addition, the first circuit board181a,the second circuit board182aand the third circuit board183aare all disposed in a housing140a,which includes a connector144a.In brief, the vehicle radar device100amay be featured the same as those of the vehicle radar device100, which are recited in the aforementioned 1st and 4th embodiments. The vehicle radar devices100and100amay be different devices, and the physical structures respectively of the vehicle radar devices100and100aare symmetrically relative to the longitudinal centerline y of the vehicle40. Alternately, the vehicle radar devices100and100amay be the same devices, and the physical structures respectively of the vehicle radar devices100and100aare symmetrically relative to the longitudinal centerline y of the vehicle40.

InFIG. 4B, the vehicle radar device100amay be communicatively connected to a vehicle control unit43of the vehicle40via the vehicle radar device100. Accordingly, the control and the interface design of the vehicle radar system4000being simplified are beneficial to be integrated with the vehicle control unit43and equipped in the vehicle40. Regarding the vehicle radar system4000in the 4th embodiment, the vehicle radar device100acts as a master radar, the vehicle radar device100aacts as a slave radar, and the vehicle radar device100ais communicatively connected to the vehicle control unit43of the vehicle40via the vehicle radar device100. The vehicle radar device100and the vehicle control unit43may be communicatively connected by CAN (Controller Area Network), and the vehicle radar device100and100amay be communicatively connected by CAN. In addition, the vehicle radar system4000may further include an alarm device4400communicatively connected to the vehicle radar device100by a wired manner or a wireless manner. The alarm device4400is configured to generate alarm signals to remind a driver of the vehicle40when the vehicle40satisfies emergency conditions. The alarm device4400may be a speaker, a buzzer, a display, or a light indicator to remind the driver by a sound or light manner, but not limited thereto.

InFIG. 4BandFIG. 4C, the radar control units130and130arespectively include switching circuits133and133aconfigured to switch the first transceivers units141,141aor the second transceiver units142,142ato be in a detection mode. Only the first transceiver units141,141aare in the detection mode when the vehicle40is in a forward state (e.g. D gear of a gear selection unit45being selected), so that the detection information of the left direction, the right direction and the rear direction of the vehicle40can be provided to achieve the BSD and LCA functions of the vehicle40. Only the second transceiver units142,142aare in the detection mode when the vehicle40is in a reverse state (e.g. R gear of the gear selection unit45being selected), so that the detection information of the rear direction of the vehicle40can be provided to achieve the reversing detection function of the vehicle40. Therefore, the vehicle40is advantageous in switching the first transceivers units141,141aor the second transceiver units142,142ato be in the detection mode according to the forward state or the reverse state thereof.

FIG. 4Gis a schematic view of the first transceiver units141and141ain the detection mode according to the 4th embodiment. InFIG. 4AandFIG. 4G, the first transceiver units141and141aboth have angles of arrival (AOA) above 30 degrees and detection distances between 50 m and 70 m. When the vehicle radar devices100and100aare applied to the BSD function of the vehicle40, based on a relative position and a relative speed of a moving object (or the target vehicle) with respect to the vehicle40, it would be determined if the moving object is within a blind zone of the vehicle40, and the driver would be timely reminded the risks associated with changing lanes and other movements. When the vehicle radar devices100and100aare applied to the LCA function of the vehicle40, the vehicle radar devices100and100aare configured to compute the movement information of the moving objects in the left, right and rear directions and obtain the current state (e.g. the forward state or the reverse state) of the vehicle40, and then the alarm device4400would remind the driver to aid to determine the lane change timing to prevent from the traffic accident caused by the lane change.

In detail, when the vehicle radar devices100and100aare applied to the BSD and LCA functions of the vehicle40, the operation frequency thereof is about 77 GHz or 79 GHz, and a voltage range thereof is 9 V to 16 V. The BSD mode can be triggered or activated to enable the first transceiver units141and141awhen the vehicle40is in the forward state, or the BSD mode can be activated while the vehicle40being in the forward state and a vehicle speed being greater than 10 kph calculated by a vehicle speed calculation unit46. When the vehicle radar devices100and100aare applied to the LCA function of the vehicle40, the LCA mode can be activated while the BSD mode being activated and the vehicle speed being greater than 20 kph. The BSD mode can be terminated and followed by the LCA mode being terminated, while the vehicle40being in the reverse mode or the vehicle speed being smaller than 10 kph. Therefore, the vehicle radar system4000are advantageous in detecting multiple target vehicles (e.g. target vehicles81and82) to analyze the distance and speed information with respect to the vehicle40so as to obtain information of TTC (Time-to-Collision) between each target vehicle and the vehicle40. One target vehicle closest to the vehicle40among the target vehicles, which reach a TTC threshold (Le. one of first emergency conditions), acts as an alarm target, and then the alarm device4400generates the alarm signal to remind the driver.

In addition, when the vehicle radar devices100and100aare applied to the LCA function of the vehicle40, an alarm threshold (another of the first emergency conditions, which causes the alarm device4400to generate the alarm signal) of a rear side of the vehicle40being approached by the target vehicle is TTC5seconds, and a distance range of 35 m to 10 m between the target vehicle and the rear side of the vehicle40or a distance range of 0.5 m to 5 m between the target vehicle and a left side or a right side of the vehicle40. The conditions of the alarm device4400stopping the alarm signal are a distance range of 10 m to 25 m between the target vehicle and the left side or the right side of the vehicle40and the vehicle40being approached by the target vehicle with TTC>2 seconds, or a distance being greater than 20 m between the target vehicle and the rear side of the vehicle40, or a distance being greater than 3 m between the target vehicle and the left side or the right side of the vehicle40. The LCA mode is terminated while the vehicle40being in the reverse mode or the vehicle speed being smaller than 20 kph. The LCA mode being terminated follows the BSD mode being terminated.

FIG. 4His a schematic view of the parameters NT2and WT2according to the 4th embodiment. InFIG. 1A,FIG. 4AandFIG. 4H, the second transmitting elements162of the vehicle radar device100may be the second narrow-angle transmitting elements160and the second wide-angle transmitting elements166, and the radar control unit130is for switching the second narrow-angle transmitting elements160or the second wide-angle transmitting elements166to operate. The second receiving elements172of the vehicle radar device100may be the second narrow-angle receiving elements170and the second wide-angle receiving elements177, and the radar control unit130is for switching the second narrow-angle receiving elements170or the second wide-angle receiving elements177to operate. The second transmitting elements of the vehicle radar device100amay be a plurality of second narrow-angle transmitting elements and a plurality of second wide-angle transmitting elements (not shown in drawings), and the radar control unit130ais for switching the second narrow-angle transmitting elements or the second wide-angle transmitting elements to operate. The second receiving elements of the vehicle radar device100amay be a plurality of second narrow-angle receiving elements and a plurality of second wide-angle receiving elements (not shown in drawings), and the radar control unit130ais for switching the second narrow-angle receiving elements or the second wide-angle receiving elements to operate.

When the second transceiver units142and142aare in the detection mode, an angle of a central blind zone (its reference numeral is omitted) defined by the radiation pattern of the second narrow-angle receiving element170disposed at the left-rear corner49L and the radiation pattern of the second narrow-angle receiving element disposed at the right-rear corner49R is NT2, that is, the central blind zone is formed between angles of arrival of horizontal plans of the aforementioned second narrow-angle receiving elements. The parameter NT2is as showing inFIG. 4Hand has a value about 80 degrees. An angle of a central blind zone (its reference numeral is omitted) defined by the radiation pattern of the second wide-angle receiving element177disposed at the left-rear corner49L and the radiation pattern of the second wide-angle receiving element disposed at the right-rear corner49R is WT2, That is, the central blind zone is formed between angles of arrival of horizontal plans of the aforementioned second wide-angle receiving elements. The parameter WT2is as showing inFIG. 4Hand has a value about 140 degrees. Thus, the vehicle radar system4000of the 4th embodiment may satisfy the following conditions: 15 degrees≤NT2≤120 degrees; and 60 degrees≤WT2≤175 degrees. Therefore, the radar control units130and130awould switch from the second narrow-angle transmitting/receiving elements (middle and short range antennas) to the second wide-angle transmitting/receiving elements (short range antennas) along with an obstruct approaching the rear side of the vehicle40so as to accurately detect the obstruct behind the vehicle40. Furthermore, signals generated by the second antenna arrays152and152aform an intersection network. The central blind zone is formed out of the intersection network. When the angles of the central blind zones are larger, the detection coverages are larger.

Moreover, the conventional ultrasonic radar usually has smaller detection angle, and thereby multiple conventional ultrasonic radars are required (four radars required generally) to be equipped to coverage the rear area of the vehicle. The vehicle radar devices100and100aaccording to the present disclosure are millimeter wave radars, it is beneficial to apparently improve the detection problems resulted from blind zone and adjust the detection angles via the design of the second antenna arrays152and152a(or the second circuit boards182and182a). Thus, the vehicle radar devices100and100arespectively disposed at the left-rear corner49L and the right-rear corner49R can coverage the rear detection of the vehicle40so as to prevent the bumper from being punched and reduce time and manpower during installing.

A transmitting signal of the second transceiver units142and142amay be generated with at least one of a time division multiplexing manner, a frequency division multiplexing manner and an orthogonal signal manner controlled by the radar control units130and130a.Therefore, the second transceiver units142and142acan be effectively prevented from detection interference caused by a rear overlapping zone of the vehicle40.

When the vehicle radar devices100and100aare applied to the reversing detection function of the vehicle40, the operation frequency thereof is about 77 GHz or 79 GHz, and a voltage range thereof is 9 V to 16 V. The reversing detection mode can be triggered or activated to enable the second transceiver units142and142awhen the vehicle40is in the reverse state, or the reversing detection mode can be activated while the vehicle40being in the reverse state and the vehicle speed being smaller than 8 kph calculated by the vehicle speed calculation unit46. When second emergency condition related to the distance, the vehicle speed or TTC is satisfied, the alarm device4400generates an alarm signal. The radar control units130and130awould switch from the second narrow-angle transmitting/receiving elements (middle and short range antennas, long detection distance, and long alarm distance) to the second wide-angle transmitting/receiving elements (short range antennas, short detection distance, and short alarm distance) along with an obstruct approaching the rear side of the vehicle40so as to accurately detect the obstruct behind the vehicle40.

FIG. 5Ais a block diagram of a vehicle radar system5000according to the 5th embodiment of the present disclosure, which is disposed in a vehicle50.FIG. 5Bis a block diagram of the vehicle radar system5000according to the 5th embodiment. InFIG. 2,FIG. 5AandFIG. 5B, the vehicle radar system5000is disposed in the vehicle50and includes two vehicle radar devices, i.e. vehicle radar devices200aand200recited in the aforementioned 2nd embodiment, which are respectively disposed at a left-rear corner and a right-rear corner of the vehicle50. The vehicle radar device200amay be featured the same as those of the vehicle radar device200, which are recited in the aforementioned 2nd embodiment.

The vehicle radar device200includes the radar control unit230, a first transceiver unit241and a second transceiver unit242. The first transceiver unit241is communicatively connected to the radar control unit230and includes the first antenna array251, and the second transceiver unit242is communicatively connected to the radar control unit230and includes the second antenna array252. The vehicle radar device200aincludes a radar control unit230a,a first transceiver unit241aand a second transceiver unit242a.The first transceiver unit241ais communicatively connected to the radar control unit230aand includes a first antenna array (not shown in drawings), and the second transceiver unit242ais communicatively connected to the radar control unit230aand includes a second antenna array (not shown in drawings). Specifically, each unit of the first transceiver units241,241aand the second transceiver units242,242ais in a detection mode when the vehicle50is in the start state. The radar control units230,230aare configured to determine if the vehicle50satisfies a first emergency condition (e.g. the first emergency condition recited in the 4th embodiment) in accordance with data from the first transceiver units241,241a.The radar control units230,230aare also configured to determine and if the vehicle50satisfies a second emergency condition (e.g. the second emergency condition recited in the 4th embodiment) in accordance with data from the second transceiver units242,242a.The vehicle radar system5000further includes an alarm device5400communicatively connected to the radar control units230,230a(specifically, the alarm device5400is communicatively connected to the radar control unit230avia the radar control unit230). The alarm device5400is controlled by the radar control units230,230ato generate an alarm signal when the vehicle50is in a forward state according to data of a vehicle control unit53, a gear selection unit55and a vehicle speed calculation unit56and satisfies the first emergency condition, and the alarm device5400is controlled by the radar control units230,230ato generate another alarm signal when the vehicle50is in a reverse state and satisfies the second emergency condition. Therefore, all of the first transceiver units241,241aand the second transceiver units242,242atransmit and receive signals, i.e. continue to operate, when the vehicle50is in the start state, instead of being activated based on the gear selection. Furthermore, an alarm signal associated to the BSD, LCA functions or an alarm signal associated to the reversing detection function can be selected to generate by the alarm device5400according to the gear selection, so that a switching circuit for switching among transceiver units or among antenna channels (selecting first antenna array or second antenna array) can be omitted.

In addition, regarding the vehicle radar system5000of the 5th embodiment, except the characteristics recited in the last paragraph being different from the characteristics recited in the aforementioned 4th embodiment, the other characteristics of the vehicle radar system5000may be the same as the corresponding characteristics of the vehicle radar system4000.