CN202748846U - DSRC (Dedicated Short Range Communication)-based vehicle positioning device and DSRC application system - Google Patents

Abstract

The application discloses a vehicle positioning device and a DSRC (Dedicated Short Range Communication) application system. The vehicle positioning device comprises a positioning antenna, a signal receiver, a digital processor, and a digital beam shaper, wherein the positioning antenna comprises at least three receiving antennas which are arranged on a same straight line, and the receiving antennas are used for receiving microwave signals sent by a same OBU (On-Board Unit); the signal receiver is connected with the positioning antenna and used for receiving the microwave signals and then inputting the microwave signals into the digital processor; the digital processor is connected with the signal receiver and used for performing digital processing on the microwave signals; and the digital beam shaper is connected with the digital processor and used for performing weighted summation processing on the signals after digital processing to form beam signals, determining an azimuth angle corresponding to the beam signals with the maximum signal-to-noise ratio, and obtaining position information of the OBU. According to the application, the positioning process is less prone to being affected by signal reflection and multi-path fading so that the precision is relatively high; and the vehicle positioning device is conductive to enabling an RSU (Rate Sensor Unit) to accurately judge whether the OBU sending the microwave signals is in a lane region covered by an RSU antenna or not, and the normal operation of the DSRC application system is ensured.

Description

DSRC-based vehicle positioning device and DSRC application system

Technical Field

The present application relates to the field of Intelligent Transportation (ITS), and more particularly, to a Dedicated Short Range Communication (DSRC) based vehicle positioning device and DSRC application System.

Background

In an Electronic Toll Collection (ETC) system, a Road Side Unit (RSU) arranged On a Road and an On-board Unit (OBU) installed On a vehicle carry out information interaction through a DSRC technology, the RSU only needs to communicate with the OBU in a lane area covered by an antenna of the RSU so as to keep the accuracy and reliability of communication and charging. Sometimes, however, the RSU cannot determine and identify whether the OBU is in the lane area covered by the antenna of the RSU, and therefore the RSU may communicate with all the OBUs that send out the response signals, for example, some OBUs in other lane areas may continue to communicate with the RSU by sending out the response signals to the RSU by mistake due to receiving the reflected RSU signals. When the RSU communicates with a plurality of OBUs at the same time, the problems of adjacent lane interference or vehicle following interference and the like easily occur, which causes fee deduction errors, for example, some vehicles are repeatedly paid fee deduction, and some vehicles are not charged, thereby affecting the normal operation of the ETC system. Especially when the ETC system is applied in a Multi Lane Free Flow (MLFF) mode, since a road does not separate lanes and provide a barrier, a vehicle allows high-speed traffic without defining lanes, and thus it is easy to have situations where an OBU communicates with a plurality of RSUs or where the same RSU communicates with a plurality of OBUs.

To avoid this, the ETC system introduces vehicle location technology to ensure that the RSU communicates only with OBUs in the area of the roadway covered by the RSU antenna to ensure proper communication and charging. An existing vehicle positioning technology applied to an ETC system is disclosed in Chinese invention patent, namely, 27.2010, 201010608098.0 application date, 201010608098.0 application number and named as positioning device and method of a vehicle-mounted unit in the ETC system, wherein a plurality of receiving antennas with different positions are arranged in an RSU and are respectively used for receiving microwave signals sent by an OBU, and the OBU is positioned by comparing the field intensity of the microwave signals received by the different receiving antennas and combining the positions of the different receiving antennas.

Disclosure of Invention

The application provides a vehicle positioning device and a DSRC application system for improving positioning accuracy.

According to a first aspect of the present application, there is provided a vehicle positioning device comprising:

the positioning antenna comprises at least three receiving antennas which are arranged on the same straight line, and the receiving antennas are used for receiving microwave signals sent by the same OBU;

the signal receiver is connected with the receiving antenna and used for receiving the microwave signal and inputting the microwave signal into the digital processor;

the digital processor is connected with the signal receiver and is used for carrying out digital processing on the microwave signal;

and the digital beam former is connected with the digital processor, performs weighted summation processing on the signals after the digital processing to form beam signals, and determines the azimuth angle corresponding to the beam signal with the maximum signal-to-noise ratio.

In one embodiment, the signal receiver further comprises an amplitude phase calibrator connected to the signal receiver.

In one embodiment, the digital beamformer further comprises a beam controller connected to the digital beamformer.

In one embodiment, the equivalent phase centers of two adjacent receiving antennas are equally spaced.

In one embodiment, the equivalent phase centers of two adjacent receiving antennas are spaced apart by half the wavelength of the microwave signal.

In one embodiment, the digital beam former further comprises a transceiving antenna, a modulator/demodulator, a coder/decoder and a core processor which are connected in sequence, and the digital beam former is connected with the core processor.

In one embodiment, the positioning antennas have two sets, and the arrangement directions of the receiving antennas in the two sets of positioning antennas are perpendicular to each other.

According to a second aspect of the present application, there is provided a DSRC application system comprising the positioning device described above.

In one embodiment, the DSRC application system is a single-lane electronic toll collection system with a rail, a single-lane free flow system or a multi-lane free flow system, and the positioning antenna is disposed on a corresponding lane of the single-lane electronic toll collection system with a rail or the single-lane free flow system, or on at least one free flow section of the multi-lane free flow system. .

The beneficial effect of this application is: the method and the device accurately position the OBU installed on the vehicle on the road based on the beam forming technology, can obtain the azimuth angle corresponding to the formed beam, the azimuth angle is the azimuth angle corresponding to the microwave signal sent by the OBU, and can calculate the position information of the OBU according to the azimuth angle. The positioning method is not easily affected by signal reflection and multipath fading, is high in precision, and is beneficial to accurately judging whether the OBU sending the microwave signal is in a lane area covered by the RSU antenna by the RSU, if so, the RSU communicates with the RSU, otherwise, the RSU does not communicate with the RSU, the problems of adjacent lane interference and vehicle following interference can be effectively solved, the charge deduction error of an ETC system is avoided, the normal operation of the ETC system is ensured, or positioning information is provided for other various DSRC application systems, and the accurate real-time monitoring or management of the vehicle is ensured.

Drawings

Fig. 1 is a schematic layout diagram of positioning antennas in an RSU according to an embodiment of the present application;

FIG. 2 is a block diagram of a positioning device according to an embodiment of the present application;

FIG. 3 is a block diagram of an RSU according to an embodiment of the present application;

FIG. 4 is a flow chart of a vehicle locating method according to an embodiment of the present application;

fig. 5 is a flowchart illustrating information interaction between an RSU and an OBU according to an embodiment of the present application.

Detailed Description

The present invention will be described in further detail with reference to the following detailed description and accompanying drawings.

In the embodiment of the application, a plurality of receiving antennas are used for receiving microwave signals sent by the same OBU, the microwave signals are subjected to A/D conversion and then transmitted to a digital beam former for beam forming, and finally an azimuth angle corresponding to a formed beam is obtained through a spatial filtering technology, so that the position information of the OBU is determined.

The first embodiment is as follows:

the vehicle positioning method is based on information interaction between the RSU and the OBU. Wherein the RSU comprises an outdoor unit having a transceiving antenna for transmitting and receiving microwave signals to and from the OBU, and an indoor unit for controlling the RSU outdoor unit and processing information received and transmitted by the RSU outdoor unit, the RSU outdoor unit being generally installed above or at a side of a road; the OBU also has an antenna for transmitting and receiving microwave signals to and from the RSU, which is typically mounted within the vehicle, for example, fixed to the front windshield of the vehicle.

Referring to fig. 1 or fig. 2, the present embodiment discloses a vehicle positioning device, which is disposed in an RSU of an ETC system, and mainly includes:

the positioning antenna is provided in the RSU outdoor unit, an antenna array is formed by at least three receiving antennas 11 arranged in the same straight line, each receiving antenna 11 is used for receiving the microwave signal transmitted by the same OBU, and one receiving antenna 11 is used as one array element, for example, in the present embodiment, the receiving antennas 11 have N (N is a natural number greater than 3), and in order to improve the positioning accuracy, the distance d between the equivalent phase centers of two adjacent receiving antennas 11 may be set to be equal, and the distance d is preferably half of the wavelength λ of the microwave signal transmitted by the OBU. One embodiment may set the number of the receiving antennas 11 to 8 in consideration of calculation speed, complexity, and size of a beam pattern, and a volume size of the outdoor unit. Those skilled in the art can understand that the receiving antennas 11 are arranged on the same straight line, which means that equivalent phase centers of the receiving antennas 11 are located on the same straight line, in order to avoid influence on measurement accuracy caused by inconsistent amplitudes of signal receiving paths corresponding to the receiving antennas 11, the same receiving antennas are selected as much as possible, for example, circularly polarized horn antennas are all selected, and since the horn antennas with higher gain (generally, gain is greater than 12 dBi) are adopted as the receiving antennas 11, the directivity of the horn antennas is stronger, interference signals are well suppressed, and positioning accuracy higher than that of common antennas can be achieved. In this embodiment, the microwave signal for positioning sent by the OBU may be any microwave signal in the communication process with the OBU.

And a plurality of signal receivers 12, one-to-one connected to each receiving antenna 11 of the positioning antennas, for receiving the microwave signals from each receiving antenna 11, converting the high frequency microwave signals into low frequency signals by frequency conversion, amplifying and filtering the low frequency signals to make the signals meet the requirements of A/D conversion, and finally inputting the microwave signals to the digital processor. The processed signal has the same gain, phase and other index parameters, and the minimum amplitude and phase measurement error among the signal receiving channels is ensured, so that the positioning precision is improved.

The digital processor includes an a/D unit 13 connected to the signal receiver 12, and is configured to perform an a/D conversion on the microwave signal output by the signal receiver 12 to obtain a digital signal, perform a frequency conversion processing and a digital filtering on the digital signal to obtain I, Q orthogonal signals, and finally input the signals to the digital beam former 14.

And a Digital Beam Former (DBF) 14, in signal connection with the digital processor, configured to perform signal superposition and beam forming on the digitally processed signal, and determine an azimuth angle corresponding to the formed beam through spatial filtering, where the azimuth angle is an azimuth angle of a microwave signal sent by the OBU, or an included angle between the microwave signal and a normal of the antenna array. The Digital beam former 14 adopts the Field Programmable Gate Array (FPGA) and Digital Signal Processing (DSP) technology to perform fast parallel mathematical operation Processing on each Array element Signal, and performs weighted summation Processing on each Array element Signal according to the maximum Signal-to-noise ratio algorithm principle optimized by the adaptive filtering algorithm, and finally forms a beam Signal, and finally determines the azimuth angle corresponding to the beam Signal with the maximum Signal-to-noise ratio, i.e. the included angle between the microwave Signal from the OBU and the antenna Array normal, after the included angle is obtained, the Digital Beam Former (DBF) 14 inputs the value of the included angle into the core processor, so that the Digital beam former combines the installation height and the angle of the receiving antenna 11 to calculate the specific coordinates of the OBU in the front of the vertical projection point of the RSU antenna.

Specifically, as shown in fig. 1, in the positioning antenna, assuming that the distance between the receiving antennas 11 is d and the incident direction of the microwave signal (i.e. the angle between the receiving antenna 11 and the normal of the antenna linear array) is θ, if the receiving antenna 11 labeled 1 in fig. 1 is taken as a time reference antenna, the wave path difference of the microwave signal from the OBU reaching the adjacent receiving antenna 11 is dsin θ, and the time difference of the microwave signal reaching the adjacent receiving antenna 11 is:

$\mathrm{\Δ\τ}=\frac{d\sin \mathrm{\θ}}{C}$ where C is the speed of light.

The phase difference between the microwave signals received by the adjacent receiving antennas 11 is:

λ is the center wavelength of the frequency to which the microwave signal corresponds.

The microwave signals received by the antennas 11 with the respective numbers are respectively:

x₁(t)=s(t)e^jωt

$x_2\left(t\right)=s\left(t\right)e^{\mathrm{j\&omega;<figure-callout\; id="2"\; label="t\; e\; j"\; filenames="HDA00001773584700011.png,HDA00001773584700012.png"\; state="\{\{state\}\}">t</figure-callout>}}{e}^j{\frac{2\mathrm{\&pi;}}{\mathrm{\&lambda;}}d\sin \mathrm{\&theta;}}^{}$

$x_N\left(t\right)=s\left(t\right)e^{\mathrm{j\&omega;<figure-callout\; id="2"\; label="t\; e\; j"\; filenames="HDA00001773584700011.png,HDA00001773584700012.png"\; state="\{\{state\}\}">t</figure-callout>}}{e}^j{\frac{2\mathrm{\&pi;}}{\mathrm{\&lambda;}}(N-1)d\sin \mathrm{\&theta;}}^{}$

microwave signals received by the antenna array are written into a matrix form as follows:

$\underset{\&OverBar;}{X}\left(t\right)=\left[\begin{array}{c}{x}_1\left(t\right)\\ x_2\left(t\right)\\ \&CenterDot;\&CenterDot;\&CenterDot;\\ x_N\left(t\right)\end{array}\right]=s\left(t\right)e^{\mathrm{j\&omega;t}}\left[\begin{array}{c}1\\ {\mathrm{<figure-callout\; id="2"\; label="e\; j"\; filenames="HDA00001773584700011.png,HDA00001773584700012.png"\; state="\{\{state\}\}">e</figure-callout>}}^j\\ \&CenterDot;\&CenterDot;\&CenterDot;\\ {\mathrm{<figure-callout\; id="2"\; label="e\; j"\; filenames="HDA00001773584700011.png,HDA00001773584700012.png"\; state="\{\{state\}\}">e</figure-callout>}}^j\end{array}\right]=s\left(t\right)\underset{\&OverBar;}{\mathrm{\&alpha;}}\left(\mathrm{\&theta;}\right)$

wherein,αand (theta) is a direction vector of the microwave signal, and the value depends on the geometry of the antenna array (known) and the propagation direction of the microwave signal (unknown).

After the N received microwave signals are weighted and summed, the output shaped signal is:

y(t)=W ^H X(t)=s(t)W ^H α(θ)

let P _W (θ)=W ^H α(theta) is the signal weighted pattern whenW ^HTo a certain directionθ ₀ P obtained when the signals of (A) are added in phase _w (θ₀) Has the maximum modulus value, can form the maximum signal-to-noise ratio in the incoming wave direction of the microwave signal, forx(t) the spatial sampling signal is actually realized, and thus the azimuth angle corresponding to the beam signal with the maximum signal-to-noise ratio is calculated, namely, the azimuth angle is determined through spatial filteringθ ₀ The azimuth is the angle between the microwave signal from the OBU and the normal of the antenna array.

Furthermore, the positioning device further comprises an amplitude-phase calibrator 15 connected to each signal receiver 12 in the positioning antenna, and configured to perform amplitude-phase calibration on each signal receiving path according to a certain timing period when the receiving antenna 11 is idle according to system requirements, so as to avoid signal amplitude-phase inconsistency occurring when the device is aged, and the temperature of the working environment changes.

The positioning apparatus further comprises a beam controller 16 connected to the digital beam former 15 for controlling the digital beam former 15 according to preset constraints, to which an optimal weighting vector control signal is provided.

The above signal receiver, digitizer processor and digital beamformer 14 are all located in the RSU indoor unit. In this embodiment, each ETC lane is equipped with an RSU outdoor unit, which is mounted on a portal frame at the center above the lane, and a plurality of receiving antennas 11 arranged on the same straight line in the positioning antennas are parallel to the ground of the lane, and the center of the antenna pattern is opposite to the incoming direction, so as to cover the width of one lane.

As shown in fig. 3, in general, the positioning device of the above embodiment forms a positioning path of the RSU, the RSU further includes a signal transceiving path including a transceiving antenna 21, a modulator/demodulator 22, a coder/decoder 24 and a core processor 25, which are connected in sequence, and the digital beam former 14 in the positioning device is further connected to the core processor 25.

The transceiving antenna 21 is used for transmitting an RSU downlink microwave signal to the OBU and receiving a microwave signal returned by an OBU response, and is connected to the signal receiver 22, and different antenna structures are specifically selected according to different coverage areas. The directional patterns of the positioning antenna and the transceiving antenna 21 are the same, so that the interference of the OBU or other signals of a bypass can be reduced, and the consistency of the microwave signals received by the transceiving antenna 21 and the OBU signals received by the positioning antenna is ensured

The signal receiver 22 is configured to amplify and output the RSU downlink microwave signal from the modulator/demodulator 23, and convert the microwave signal returned by the OBU response into an intermediate frequency signal after receiving the intermediate frequency signal, and input the intermediate frequency signal into the modulator/demodulator 23 after amplifying and filtering the intermediate frequency signal.

The modulator/demodulator 23 is configured to modulate the RSU downlink microwave signal and transmit the modulated RSU downlink microwave signal to the signal receiver 22, and demodulate the microwave signal returned by the OBU response and input the demodulated microwave signal to the encoder/decoder 24.

The coder/decoder 24 is configured to perform FM0 coding on the RSU downlink microwave signal and send the RSU downlink microwave signal to the modulator/demodulator 23, and perform FM0 decoding on the microwave signal returned by the OBU response and input the microwave signal into the core processor 25.

The core processor 25 is a main processor of the whole RSU, and is used for controlling the whole working process of the RSU, performing data interaction with a lane computer, and managing an ETC application logic process. The core processor 25 is further in signal connection with the digital beam former 14, the beam controller 16, and the amplitude and phase calibrator 15, and is capable of receiving the azimuth angle of the microwave signal determined by the digital beam former 14, calculating the position information of the OBU based on the azimuth angle, controlling the operation of the beam controller 16, and sending an instruction to the amplitude and phase calibrator at the idle position of the receiving antenna 11 to perform amplitude and phase calibration on each signal receiving path, thereby improving the positioning accuracy as much as possible by reducing the amplitude and phase error between each signal receiving path.

Example two:

unlike the first embodiment, the positioning device of the first embodiment has a set of positioning antennas for positioning the microwave signal from the OBU in one dimension, for example, a set of positioning antennas along the extending direction (longitudinal direction) of the road is used, and the longitudinal position coordinates of the OBU in the coverage area in front of the vertical projection point of the RSU antenna are calculated by taking the angle between the microwave signal and the normal of the antenna array as the pitch angle of the OBU after the first embodiment obtains the angle. The positioning antennas of the embodiment are provided with two groups, the arrangement directions of the receiving antennas in the two groups of positioning antennas are mutually perpendicular, in addition to obtaining the longitudinal position coordinate of the OBU, a group of positioning antennas along the direction perpendicular to the road extension direction (transverse direction) can be used, the included angle between the microwave signal and the normal line of the antenna array is obtained by adopting the same positioning mode as the embodiment, and then the included angle is used as the inclined angle of the OBU, so that the transverse position coordinate of the OBU in the coverage area in front of the vertical projection point of the RSU antenna is calculated, and the two-dimensional positioning of the vehicle is realized.

Example three:

referring to fig. 4, the present embodiment discloses a vehicle positioning method, which includes the following steps:

step S100: the RSU receives microwave signals sent by the same OBU by utilizing at least three receiving antennas which are arranged on the same straight line in the positioning antennas.

And S101, carrying out digital processing on the microwave signal received by the receiving antenna by using a digital processing unit.

Step S102: and utilizing a beam former to perform weighted summation processing on the digitized signals according to a maximum signal-to-noise ratio algorithm principle optimized by an adaptive filtering algorithm to form beam signals, and determining an azimuth angle corresponding to the beam signals with the maximum signal-to-noise ratio to obtain the position information of the microwave signals sent by the OBU.

Example four:

referring to fig. 3 and fig. 5, the present embodiment discloses a process of information interaction between an RSU and an OBU, including the following steps:

step S200: the OBU enters an antenna signal coverage area of the RSU, is awakened upon receiving an awakening signal of the RSU, and then receives a microwave signal of the RSU, where the microwave signal carries a request data frame, and the specific content of the request data frame is determined according to the need, and is generally used for requesting the OBU to return certain information to the RSU, for example, the request data frame of this embodiment is used for requesting vehicle information (including one or more of information such as license plate number, vehicle model, vehicle color, and the like).

Step S201: after receiving the microwave signal of the RSU, the OBU analyzes the microwave signal, then obtains the vehicle information requested by the RSU through internal calculation, encapsulates the vehicle information into a response data frame, and then sends the microwave signal to the RSU, wherein the microwave signal comprises the response data frame, the ID of the OBU and other information. The microwave signal is received by the positioning antenna and the transceiver antenna in the RSU outdoor unit at the same time, the processing flow after the positioning antenna receives the microwave signal is as follows in steps S202-S205, the processing flow after the transceiver antenna receives the microwave signal is as follows in steps S206-S209, and the process proceeds to step S210 after both processing flows are finished.

Step S202: at least three receiving antennas 11 in the positioning antenna simultaneously and respectively receive microwave signals sent by the OBU.

Step S203: each signal receiver 12 receives the microwave signal from the receiving antenna 11, and converts the high frequency signal into an intermediate frequency signal, which is then amplified and filtered.

And step S204, the digital processing unit performs A/D conversion on the microwave signal from the signal receiver by using the A/D unit 13, and then performs frequency conversion and filtering processing on the converted digital signal again.

Step S205, the digital beam former 14 performs weighted summation processing on each array element signal, forms a beam signal, determines an azimuth angle corresponding to the beam signal with the maximum signal-to-noise ratio, the azimuth angle is an included angle between a microwave signal from the OBU and a normal line of the antenna array, obtains the included angle by the numerical value of the included angle, and calculates a specific coordinate of the OBU in a coverage area in front of a vertical projection point of the RSU antenna as the positioning information of the OBU by combining the installation height and the angle of the receiving antenna,

step S206: the transceiver antenna 21 receives the microwave signal of the OBU.

Step S207, the signal receiver 22 receives the microwave signal from the transmitting/receiving antenna 21, and amplifies and filters the microwave signal and converts the high frequency signal into an intermediate frequency signal.

Step S208: the modulation/demodulation unit 23 demodulates the microwave signal from the signal receiver.

Step S209: the encoding/decoding unit 24 decodes the signal from the modulation/demodulation unit, thereby acquiring specific information contained in the response data frame.

Step S210: the core processor 25 judges the validity of the microwave signal according to the information decoded by the coding/decoding unit 24 in the signal transceiving path, if the microwave signal is valid, judges whether the OBU is in the antenna signal coverage area of the RSU according to the positioning information of the OBU obtained by the positioning path, if so, continues to communicate with the OBU to complete the ETC transaction logic process, and deducts the fee, and if not, does not communicate with the OBU.

Step S211: after the deduction is completed, the RSU can also wait for the lane computer to send an OBU searching instruction or send a wake-up signal and a microwave signal carrying a request data frame to the OBU again, and if the microwave signal carrying a response data frame of the OBU is not received within the appointed timing time, a signal amplitude and phase calibration instruction is sent to the amplitude and phase calibrator.

The vehicle positioning device of the above embodiment of the application can be widely applied to various DSRC systems, such as a single-lane barrier machine ETC system, a single-lane free flow system, a multi-lane free flow system, and various vehicle monitoring systems such as a vehicle speed measuring system, a vehicle type recognition system, an image recognition system, and an image snapshot system for real-time monitoring or violation inspection of vehicles. The positioning antenna is arranged on a corresponding lane of a single-lane electronic ETC system with a railing machine or a single-lane free flow system or at least one free flow section in a multi-lane free flow system, and whether a vehicle is in the antenna coverage area of the RSU can be confirmed through accurate positioning of the vehicle, so that the phenomena of following interference, side-lane interference and the like are effectively avoided. The OBU positioning method is accurate, the transformation of the current RSU equipment is small, and particularly in an MLFF system, the RSU can accurately position vehicles passing freely on multiple lanes, so that fee deduction errors are reduced, and normal charging is guaranteed.

Those skilled in the art will appreciate that all or part of the steps of the various methods in the above embodiments may be implemented by instructions associated with hardware via a program, which may be stored in a computer-readable storage medium, and the storage medium may include: read-only memory, random access memory, magnetic or optical disk, and the like.

The foregoing is a more detailed description of the present invention that is presented in conjunction with specific embodiments, and the practice of the invention is not to be considered limited to those descriptions. It will be apparent to those skilled in the art that a number of simple derivations or substitutions can be made without departing from the inventive concept.

Claims (9)

1. A vehicle positioning device, comprising:

the positioning antenna comprises at least three receiving antennas which are arranged on the same straight line, and the receiving antennas are used for receiving microwave signals sent by the same vehicle-mounted unit;

the signal receiver is connected with the receiving antenna and used for receiving the microwave signal and inputting the microwave signal into the digital processor;

the digital processor is connected with the signal receiver and is used for carrying out digital processing on the microwave signal;

and the digital beam former is connected with the digital processor, performs weighted summation processing on the signals after the digital processing to form beam signals, and determines the azimuth angle corresponding to the beam signal with the maximum signal-to-noise ratio.

2. The apparatus of claim 1, wherein equivalent phase centers of two adjacent receive antennas are equally spaced.

3. The apparatus of claim 2, wherein the spacing between equivalent phase centers of two adjacent receiving antennas is half the wavelength of the microwave signal.

4. The apparatus of claim 1, further comprising an amplitude and phase calibrator coupled to the signal receiver.

5. The apparatus of claim 1, further comprising a beam controller coupled to the digital beamformer.

6. The apparatus of claim 1, further comprising a transceiving antenna, a modulator/demodulator, a coder/decoder, and a core processor connected in sequence, the digital beamformer being connected to the core processor.

7. The apparatus according to any one of claims 1 to 6, wherein the positioning antennas have two sets, and the arrangement directions of the receiving antennas in the two sets of positioning antennas are perpendicular to each other.

8. A dedicated short-range communication application system, characterized by comprising the vehicle positioning apparatus of claim 7.

9. The system of claim 8, wherein the dedicated short-range communication application system is a single-lane, multi-lane banister electronic toll collection system, a single-lane free-flow system, or a multi-lane free-flow system, and the positioning antenna is disposed on a corresponding lane of the single-lane banister electronic toll collection system or the single-lane free-flow system, or on at least one free-flow profile of the multi-lane free-flow system.

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