KR102207139B1 - Communication system using antenna apparatus - Google Patents

Abstract

The present invention discloses an antenna device and a communication system using the same. According to the present invention, the antenna device comprises: a substrate unit formed of a dielectric; a patch unit formed on one surface of the substrate unit, and being a radiating element having a predetermined inclination angle formed by cutting a pair of diagonally facing corners among the square corners; a feed line formed on one surface of the substrate unit and connected to the patch unit to supply electromagnetic energy; and a conductive ground unit formed on the other surface corresponding to one surface of the substrate unit.

Description

Communication system using antenna device {COMMUNICATION SYSTEM USING ANTENNA APPARATUS}

The present invention relates to an antenna device and a communication system using the same. More specifically, it relates to an antenna device for an interior of a vehicle to which a circular polarization microstrip patch antenna structure is applied, and a communication system using the same, so as to replace the vehicle exterior antenna.

In recent years, roads, which used to be the concept of providing simple passageways, are evolving into the concept of an important living space that connects diverse and complex modern society. This is due to the emergence of the concept of Intelligent Transportation Systems (ITS), a system that can provide real-time information on surrounding traffic, unexpected situations, congestion, and danger to the driver while driving, and autonomous vehicles emerged as a social issue. In connection, it is fundamentally changing our transportation life.

In particular, as the concept of ubiquitous was introduced into the road sector due to the development of information and communication, ITS has evolved further, which is a fast, safe, and comfortable next-generation suitable for the increasingly accelerating information society with C-ITS (Cooperative-Intelligent Transport Systems). It aims to implement the transportation system.

In this C-ITS, V2X (Vehicle to Everything communication) communication is essential, which means communication between all objects centered on a vehicle, and is a wireless communication between vehicle and vehicle (V2V: Vehicle to Vehicle), between vehicle and infrastructure. It refers to wireless communication (V2I: Vehicle to Infrastructure), in-vehicle wired and wireless networking (IVN: In-Vehicle Networking), and vehicle to mobile terminal communication (V2P: Vehicle to Pedestrian).

In order to implement various information transmission/reception of such a vehicle, development of an antenna with improved reception performance that can be used in a Wireless Access in Vehicular Environment (WAVE) environment is required.

More specifically, by performing communication between the vehicle and the vehicle (V2V) and the vehicle and the roadside infrastructure (V2I), a cutting-edge technology that can quickly respond to an unexpected situation and minimize traffic accidents is also based on the V2X communication technology. Depending on the application service, the V2X communication system has an advantage that can significantly contribute to the prevention of traffic accidents, such as detection of dangerous substances ahead, control of traffic traffic, non-stop passing at an emergency vehicle intersection, prevention of accidents in blind spots at intersections, and detection of two-wheeled vehicles in advance.

In order to expand the safety service for preventing such traffic accidents, the most important thing is the spread of WAVE vehicle terminals, and for this, the satisfaction and convenience of system installation considering users must be secured.

1 is a view showing a conventional external antenna for a vehicle.

Referring to FIG. 1, as a conventional vehicle antenna, an external antenna 10 such as a shark antenna installed on a vehicle roof has been generally used. However, if there is an existing external antenna, there is a hassle of remodeling the vehicle itself in order to install an additional antenna.

In addition, the conventional vehicle antenna device already includes a plurality of antennas, and when it is necessary to add a V2X antenna to support V2X communication between vehicles, cable wiring and antenna installation itself are difficult, and the size of the antenna device There is a problem that can increase.

Therefore, the present invention is to solve all the problems of the prior art as described above, by adjusting the patch shape ratio of the antenna so as to replace the vehicle exterior antenna, and a vehicle internal antenna device to which a circular polarized patch antenna structure is applied, and The purpose is to provide the used communication system.

In addition, another object of the present invention is to provide a vehicle interior antenna device capable of differential power distribution according to an antenna patch arrangement, and a communication system using the same.

In addition, another object of the present invention is to provide an antenna device for an interior of a vehicle that can integrally implement a dual array antenna structure and a communication system using the same.

In addition, another object of the present invention is to provide an antenna device for an inside of a vehicle capable of providing a C-ITS service by being connected to an OBU and a communication system using the same.

The object of the present invention is a substrate portion formed of a dielectric material; A patch portion formed on one surface of the substrate portion, which is a radiating element having a predetermined inclination angle by cutting a pair of corners facing each other in a diagonal direction among square corners; A feed line formed on one surface of the substrate and connected to the patch to supply electromagnetic energy; And a conductive ground portion formed on the other surface corresponding to the one surface of the substrate.

In this case, the edge of the pair of the patch portions may have the constant inclination angles on the upper right side and the lower left side with respect to the feed line.

The inclination angle of the patch part may have a ratio of a horizontal width and a vertical length of 2.2:1 based on the feed line.

A plurality of the patch portions and the feed lines of the antenna device are arranged, and are arranged in one row and four columns at regular intervals on one surface of the substrate portion, and a power distribution unit for differentially distributing power to each patch portion through the feed line It may contain more.

The power distribution unit may differentially distribute power in a ratio of 0.1:0.4:0.4:0.1 to each of the patch units.

Patch portions and feed lines arranged in one row and four columns; And the power distribution units for differentially distributing power to each patch unit may be dually arranged.

In addition, the object of the present invention is a substrate portion formed of a dielectric material, a patch portion formed on one surface of the substrate portion and a radiating element having a constant inclination angle by cutting a pair of corners facing each other in a diagonal direction among square corners, the substrate An antenna device installed inside a vehicle, comprising: a feed line formed on one surface of the negative portion and connected to the patch portion to supply electromagnetic energy; and a conductive ground portion formed on the other surface corresponding to one surface of the substrate; And an on-vehicle device (OBU) that is connected inside the vehicle to process data signals.

In this case, the corners of the pair of the patch portions of the antenna device may have the constant inclination angles on the upper right side and the lower left side with respect to the feed line.

The inclination angle of the patch part may have a ratio of a horizontal width and a vertical length of 2.2:1 based on the feed line.

A plurality of the patch portions and the feed lines of the antenna device are arranged, and are arranged in one row and four columns at regular intervals on one surface of the substrate portion, and a power distribution unit for differentially distributing power to each patch portion through the feed line It may contain more.

The power distribution unit may differentially distribute power in a ratio of 0.1:0.4:0.4:0.1 to each of the patch units.

Patch portions and feed lines arranged in one row and four columns; And the power distribution units for differentially distributing power to each patch unit may be dually arranged.

The antenna device is an integrated module built into one case, and the case may be provided with a means for displaying a phone number.

The length of a connection cable between the antenna device installed inside the vehicle and the vehicle-mounted device OBU may be shorter than that of the external antenna.

According to the present invention, a broadband matching characteristic of a circularly polarized patch antenna can be satisfied by adjusting a patch shape ratio of an antenna.

In addition, according to the present invention, differential power distribution is possible according to the patch arrangement of antennas, thereby satisfying high gain characteristics within the WAVE communication band.

In addition, according to the present invention, by implementing a dual array antenna structure integrally, real-time processing and delay of a signal can be prevented.

In addition, according to the present invention, it is possible to provide a C-ITS service through V2X by being connected to a vehicle-mounted device (OBU) and conveniently connected to the inside of a vehicle without additional installation of an external antenna.

1 is a view showing a conventional external antenna for a vehicle.
2 is a diagram showing a single antenna device according to an embodiment of the present invention.
3 is a view showing a cross section from A to A'of FIG. 2 according to an embodiment of the present invention.
4 is a graph showing characteristics of a single antenna device according to an embodiment of the present invention.
5 is a graph showing a radiation pattern of a single antenna device according to an embodiment of the present invention.
6 is a diagram illustrating an array antenna device according to another embodiment of the present invention.
7 is a graph showing characteristics of an array antenna device according to another embodiment of the present invention.
8 is a graph showing a radiation pattern of an array antenna device according to another embodiment of the present invention.
9 is a graph showing power distribution characteristics of an array antenna device according to another embodiment of the present invention.
10 is a view showing a dual array antenna device according to another embodiment of the present invention.
11 is a photograph of manufacturing a dual array antenna device according to another embodiment of the present invention.
12 is a block diagram of a communication system using a dual array antenna device according to another embodiment of the present invention.
13 is a photograph of installing four types of antennas to test the performance of the dual array antenna device of the present invention.
14 is a graph measuring performance of a communication system including a dual array antenna device of the present invention.
15 is a diagram of a first test measuring the performance of a communication system including a dual array antenna device of the present invention.
16 is a diagram showing a first test result of FIG. 15 of the present invention.
17 is a diagram of another test condition in which the performance of the communication system including the dual array antenna device of the present invention is measured.
18 is a diagram showing the overall test result of measuring the performance of the communication system including the dual array antenna device of the present invention.
19 is a diagram showing the performance of a communication system including a dual array antenna device of the present invention according to the length of a cable.
FIG. 20 is a diagram showing overall test results obtained by measuring compatibility of a communication system including a dual array antenna device of the present invention.
21 is a test screen for measuring V2I performance of a communication system including a dual array antenna device of the present invention.
22 is a diagram showing the overall test result of measuring V2I performance of a communication system including a dual array antenna device of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art may easily implement the present invention. The present invention may be implemented in various different forms, and is not limited to the embodiments described herein.

[Preferred embodiment of the present invention]

In the present specification, the antenna device is described based on a microstrip patch antenna, which is a patch antenna. This comprehensively refers to an antenna having a structure in which a thin metal patch plate is located on a dielectric attached to the ground plate. The manufacturing method may be a printed antenna (printed circuit board), but the present invention is limited thereto. It is not. Such a microstrip patch antenna is easy to manufacture and can be integrated with a circuit. In addition, it is also possible to easily use the microstrip line feeding as a feeding method.

In the following embodiments, for convenience of description, configurations of single, array, and dual patch antennas and test results for confirming their characteristics will be sequentially illustrated and described.

Configuration of a single antenna

2 is a diagram showing a single antenna device according to an embodiment of the present invention.

3 is a diagram illustrating a cross section from A to A′ of FIG. 2 according to an embodiment of the present invention.

2 and 3, a single antenna device according to an embodiment of the present invention includes a substrate portion 100 and a patch portion 200 disposed on one surface of the substrate portion 100 to radiate electromagnetic energy. And, it may be configured to include a ground part 300 that is located on the other surface corresponding to one surface of the substrate part 100 and made of a conductor and connected to the patch part 200, and a feed line 210 that supplies power to the patch part 200. .

First, the substrate 100 may be formed of an insulating material. It is preferable that the substrate portion 100 is formed of a material that is an insulator and can cause an electrical induction action.

For example, a synthetic resin material having a predetermined relative dielectric constant _(r) of a dielectric material, glass epoxy, polyoxymethylene (POM: PolyOxyMethylene), acetal polymers (PolyAcetal), ABS (AcrylonitrileButadiene Styrene ) resin or PC (PolyCarbonate) resin, etc. It can be composed of. However, the present invention is not limited thereto, and a known dielectric material having a constant relative dielectric constant ( _r ) capable of causing an electrical induction may be used without limitation.

In an embodiment of the present invention, a substrate portion 100 having a relative permittivity ( _r ) of 2.5 and a thickness of 0.5 mm was used. Particularly, in the case of the microstrip antenna as in the present invention, it is a parameter that affects the radiation characteristics of the antenna according to the dielectric constant (relative dielectric constant) of the substrate 100.

Next, a patch portion 200 having an area smaller than that of the substrate portion 100 may be positioned on an upper portion, which is one surface of the substrate portion 100. The patch part 200 is composed of a conductive object through which electromagnetic waves can travel, and it is generally preferable to use a metal material.

The patch part 200 functions as a radiating element of a microstrip antenna, which is one of the planar antennas, and various shapes such as a square, a circle, and a triangle may be used without limitation, but one of the present invention. In the embodiment, a square structure may be implemented.

Preferably, a pair of corners facing each other in a diagonal direction among the square corners may be cut to implement a radiating element having a certain inclination angle, and the inclination angles at the upper right and lower left corners of the feed line 210 may be provided. I can. A more detailed description of this may be understood by the following [Table 1].

Table 1 shows the horizontal width and vertical length dimensions of the patch part 200 and the feed line 210 of a single antenna device according to an embodiment of the present invention.

In particular, by controlling the size of the patch unit 200 (L1, W1, L2, W2), it is possible to implement a circularly polarized microstrip patch antenna that satisfies the matching characteristic in the WAVE communication frequency band. First, the length (L1) and width (W1) of the patch part 200 may be formed in a square shape of 15.6 mm. At this time, the upper right side with respect to the feeding part 210 among the square corners of the patch part 200 A pair of corners facing each other in the diagonal direction of the lower left side of and can be cut to form a certain angle of inclination.

Preferably, the angle of inclination of the corners of the patch part 200 is characterized in that the ratio of the horizontal width W2 and the vertical length L2 is 2.2:1. By controlling the ratio of the inclination angle, an antenna having a patch unit 200 having a voltage standing wave ratio (VSWR) and an axial ratio suitable for a WAVE communication frequency band can be implemented.

Next, a feed line 210 that is connected to the patch part 200 and provides power supply may be positioned at an upper portion of the substrate part 100. The power supply line 210 may function as a line supplying power to the patch unit 200 for radiation of the antenna.

Finally, a ground part 300 made of a conductive material may be positioned under the other surface corresponding to one surface of the substrate 100. The ground part 300 is made of a conductive material, and the ground part 300 is separated from the patch part 200 by the substrate part 100, which is a dielectric material, but corresponds to the patch part 200, which is a radiating element. It can cause an inductive action, and it can perform the function of an electrical ground.

Characteristics of a single antenna

4 is a graph showing characteristics of a single antenna device according to an embodiment of the present invention.

5 is a graph showing a radiation pattern of a single antenna device according to an embodiment of the present invention.

Referring to FIG. 4, before adjusting the ratio of the horizontal width W2 and the vertical length L2 through tuning the inclination angle ratio of the edge of the patch 200 as described in [Table 1] It is the data measured by dividing it into 2.2:1 and After Tuning.

First, the graph (a) shows the return loss of a single antenna, and after the voltage standing wave ratio (VSWR) adjusts the inclination angle ratio of the edge of the patch 200 to 2.2:1 (After Tuning) In the frequency band from 5.855 GHz to 5.925 GHz, which is the WAVE communication band (F), a VSWR value of 1.5:1 or less is measured to confirm that the matching characteristics are satisfied.

Next, the graph (b) shows the axial ratio of a single antenna, and it can be confirmed that the circular polarization characteristic is satisfied by measuring less than 3dB in the frequency band of the WAVE communication band (F) after tuning. .

Next, referring to FIG. 5, a 2D E-plane radiation pattern is shown at the center frequency, and the maximum gain direction of the antenna is the same as the Z axis. At this time, circular polarization may satisfy 6.6dBiC.

Array antenna configuration

In the following detailed description, a patch array antenna configured by arranging a plurality of patch units 200 in the above-described single antenna device and a power distribution unit 400 for distributing power to each patch will be described. However, since the basic configurations of the substrate portion 100, the patch portion 200, the feed line 210, and the ground portion 300 of the single antenna device are the same, they will be omitted to avoid redundancy.

6 is a diagram illustrating an array antenna device according to another embodiment of the present invention.

Referring to FIG. 6, an array antenna device according to another embodiment of the present invention includes a substrate portion 100, a plurality of patch portions 200 disposed on one surface of the substrate portion 100, and the patch portion. (200) A plurality of feed lines 210 supplying electromagnetic energy for each, and a ground part 300 and the patch part 200 located on the other surface corresponding to one surface of the substrate part 100 and made of a conductor and connected to each other. ) May be configured to include a power distribution unit 400 for distributing power every time.

In this case, the plurality of patch portions 200 may be arranged in one row and four columns at regular intervals G1 and G2 on an upper portion of one surface of the substrate portion 100. For example, the gap G1 between the patch part 200 and the adjacent patch part 200 may be 19.75 mm, and the gap G2 between the center of the patch part 200 and the center of the adjacent patch part 200 ) Can be 35mm. However, the present invention is not limited thereto, and all patch array antenna configurations arranged 1×4 at regular intervals for each patch unit 200 will be included in the present invention.

Next, it may further include a power distribution unit 400 for differentially distributing power to each patch unit 200 through the feed line 210. Preferably, the power distribution unit 400 may differentially distribute power in a ratio of 0.1:0.4:0.4:0.1 to each patch unit 200.

Array antenna characteristics

7 is a graph showing characteristics of an array antenna device according to another embodiment of the present invention.

8 is a graph showing a radiation pattern of an array antenna device according to another embodiment of the present invention.

9 is a graph showing power distribution characteristics of an array antenna device according to another embodiment of the present invention.

The array antenna device according to another embodiment of the present invention is preferably implemented as a microstrip antenna in order to make a small and lightweight antenna that is convenient to manufacture. At this time, in order to compensate for the disadvantages of the microstrip antenna with low gain, the patch part 200 has a structure in which 1×4 is arranged at regular intervals in order to form a strong beam that can spread over a long distance. At the same time, in order to be strong against obstacle noise and reduce polarization loss, the characteristic of circular polarization is satisfied by adjusting the ratio (horizontal width and length of each other) of a certain inclination angle formed by cutting a pair of corners of the square corners of the patch 200 You can do it.

Referring to FIG. 7, first, a graph (a) shows the return loss of an array antenna, and a voltage standing wave ratio (VSWR) in a frequency band from 5.855 GHz to 5.925 GHz, which is a WAVE communication band (F): Voltage standing wave ratio) A VSWR value of 1.5:1 or less is measured, confirming that the broadband matching characteristic is satisfied.

Next, the graph (b) shows the axial ratio (axis ratio) of the array antenna, and it can be confirmed that the circular polarization characteristic is satisfied by measuring less than 3dB in the frequency band of the WAVE communication band (F).

Next, the graph (c) shows the peak gain (maximum gain) of the array antenna, and it can be seen that the maximum gain value of the antenna in the WAVE communication band (F) shows a high gain characteristic of 11.9 dBic or more.

Next, referring to FIG. 8, 2D E-plane radiation patterns in the yz plane and zx plane of the array antenna are shown, and the maximum gain direction of the antenna is the same as the Z-axis. First, graph (a) shows that the 2D E-plane radiation pattern half power beam width (HPBW) on the yz plane of the array antenna is about 20°, and then graph (b) shows that the array antenna It can be seen that the 2D E-plane radiation pattern half power beam width (HPBW) on the zx plane is about 73°.

Next, referring to FIG. 9, the characteristics of the power distribution unit 400 that differentially distributes power to each patch unit 200 of the array antenna can be confirmed. First, the graph (a) is in the WAVE communication band (F). When the power is supplied to the connection terminal (P), it is shown that the power of the first row and the fourth row is 6dB lower than that of the power supplied to the second and third rows of the patch 200.

Accordingly, the power distribution unit 400 can confirm that the electric power is differentially distributed in a ratio of 0.1:0.4:0.4:0.1 for each of the first, second, third, and fourth columns of the patch unit 200. Next, the graph (b) shows the distributed power phase of the array antenna, where the phase difference of the power distributed to the patch 200 in columns 1, 4 and 2, 3 in the frequency band of the WAVE communication band (F) is less than 2°. It can be seen that the distribution is in the same phase.

Configuration of dual array antenna and communication system

In the following detailed description, a dual array antenna is constructed by arranging two array antennas according to another embodiment according to the present invention, and a communication system that can be used inside a vehicle by using the two array antennas according to the present invention will be described.

However, since the basic configurations of the substrate part 100, the patch part 200, the feed line 210, the ground part 300, and the power distribution part 400 of the array antenna device are the same, they are omitted to avoid redundancy. To

10 is a view showing a dual array antenna device according to another embodiment of the present invention.

11 is a photograph of manufacturing a dual array antenna device according to another embodiment of the present invention.

First, referring to FIG. 10, two array antenna devices RF1 and RF2 arranged in 1×4 as described in FIG. 6 are disposed on the substrate 100 to implement a configuration of a dual array antenna. have. The reason for configuring the dual array antenna as described above is that delay can be prevented and real-time data processing is possible during signal transmission/reception of the antenna.

Next, referring to FIG. 11, the dual array antennas RF1 and RF2 as shown in FIG. 10 are built into one case 500, and as shown in the photographs of (a) and (b), an integrated module dual array antenna device ( 1000) can be implemented. Therefore, dual ports (two connection terminals) can be supported in one case 500, and when installed inside a vehicle, it is possible to minimize obstruction of view through installation convenience and miniaturization of size for the user. At this time, the case 500 may be made of an ABS material having a relative dielectric constant ( _r ) of 2, and as shown in the photo in (c), a means for displaying a phone number on the outside of the case 500 is further provided to the vehicle. You can also install it.

12 is a block diagram of a communication system using a dual array antenna device according to another embodiment of the present invention.

Referring to FIG. 12, a dual array antenna device 1000 receives a radio frequency (RF) signal and communicates by connecting with a vehicle-mounted device (OBU, On-Board Unit: 2000) mounted inside a vehicle supporting V2X communication. System can be provided. In this case, the dual array antenna device 1000 may be divided into a front antenna 1100 and a rear antenna 1200.

Meanwhile, a connection cable exists between the dual array antenna device 1000 and the OBU 2000, so that the dual array antenna device 1000 transmits the RF signal received from the outside to the OBU 2000, through a modulation and demodulation process and a transceiver. The V2X packet may be processed and, conversely, an RF signal generated by the OBU may be transmitted to the dual array antenna device 1000.

Characteristics of dual array antenna and communication system

In the following detailed description, the dual array antenna according to another embodiment of the present invention described above is mounted inside an actual vehicle to understand its performance. This is to verify the performance of the internal antenna of the C-ITS (Cooperative-Intelligent Transport Systems) vehicle, and a vehicle to vehicle (V2V) performance test is conducted. The test location is a round-trip driving section from Daejeon City (Yooseong World Cup Intersection) to Sejong City (in front of Yangji Middle School), the C-ITS pilot project establishment area.

To this end, a vehicle driving field test of four types of antennas (1×3 array antenna, mono-pole antenna, external Shark antenna, and 1×4 array antenna) is performed and compared with each other.

13 is a photograph of installing four types of antennas to test the performance of the dual array antenna device of the present invention.

14 is a graph measuring performance of a communication system including a dual array antenna device of the present invention.

First, referring to FIG. 13, pictures of four types of antennas are shown, where (a) is a 1×3 array antenna, (b) is a mono-pole antenna, (c) is an external Shark antenna, and (d) is 1× It is a 4 array antenna. At this time, the 1×4 array antenna is a dual array antenna device according to the present invention. In order to test the performance using these antennas, referring to FIG. 14, GPS information and reception level in the message can be stored as an auxiliary means of determining the suitability of the received V2V message. (a) shows the location information of the received V2V message. It is mapped on the map, and (b) shows the reception level when the message is successfully received.

In addition, in order to test the suitability of the C-ITS vehicle interior antenna, the V2V field test method is '1) A vehicle terminal and an antenna to be measured are installed in a stationary vehicle. 2) Set the transmission parameters in the vehicle terminal. 3) Install the vehicle terminal and the antenna to be measured in the driving vehicle. 4) Save the received message in the log.' At this time, measurement parameters are based on 10% or less of PER (Packet Error Rate) in the C-ITS communication area, and the communication area calculation method follows the contents defined in Society of Automotive Engineers (SAE) J2945-1 standard. The window technique can be applied. Since this is a known technique, a detailed description will be omitted.

Characteristics of dual array antenna and communication system (communication area)

In the following detailed description, a V2V communication area is measured for a vehicle driving field test of the above-described four types of antennas (1×3 array antenna, mono-pole antenna, external Shark antenna, and 1×4 array antenna). First, the antenna was installed in the front of the stationary transmitting vehicle (stopped vehicle), and the same antenna as the transmitting vehicle was installed in the front or rear of the message receiving vehicle (running vehicle), which is a running vehicle, to measure the communication area, respectively. At this time, the transmission vehicle (stop vehicle) was repeatedly measured while rotating by 45 degrees, and a more detailed result can be understood by the following detailed description with reference to the drawings.

15 is a diagram of a first test measuring the performance of a communication system including a dual array antenna device of the present invention.

16 is a diagram showing a first test result of FIG. 15 of the present invention.

First, referring to FIG. 15, the message stopping vehicle (transmitting vehicle) is stopped looking at the front, and the driving vehicle has the antenna at the rear of the vehicle and the communication area of the antenna is measured when traveling in the opposite direction of the stationary vehicle. . At this time, the same type of antenna is mounted on the stationary vehicle and the running vehicle and the experiment is performed, and the result of measuring the communication area of the four types of antennas can be confirmed through FIG. 16. Referring to FIG. 16, first, the measured communication area value of the Shark antenna is 309m, the measured communication area value of the 1×4 array antenna is 401m, the measured communication area value of the 1×3 array antenna is 382m, mono-pole. The measured communication area of the antenna represents a measurement result of 360m. Therefore, the measured communication area of the 1×4 array antenna shows the widest result.

17 is a diagram of another test condition in which the performance of the communication system including the dual array antenna device of the present invention is measured.

18 is a diagram showing the overall test result of measuring the performance of the communication system including the dual array antenna device of the present invention.

First, referring to FIG. 17, a test condition for repeatedly measuring a communication area while rotating a stationary vehicle (transmitting vehicle) by 45 degrees in the present invention is briefly illustrated. It proceeds in the same manner as in FIG. 15, but the test can be performed at the front (0 degrees), 45 degrees, 90 degrees, 135 degrees, and 180 degrees respectively. At this time, for each test, the driving vehicle (receiving vehicle) is driving in the opposite direction of the stopping vehicle (transmitting vehicle) with the antenna at the rear of the vehicle, and the stopping vehicle (transmitting vehicle) is driving in the direction with the antenna placed in the front of the vehicle. If so, you can test both cases.

Next, referring to FIG. 18, test results under a total of 10 conditions from the first test to the tenth test are shown. At this time, since one test is performed based on each of the four antennas, the total number of tests is 40 times.

In more detail, if the average distance of the communication area of the 1×4 array antenna is calculated, it can be seen that it is 353.5m. This is higher than the average of other antennas, the external Shark antenna (333.8m) and the 1x3 array antenna (324.3m). In addition, if you are in a vehicle traveling at a speed of 100Km, a danger detection warning must be received before a distance of at least 100m or more in order to detect and cope with the risk of an accident.The 1×4 array antenna according to the present invention has an average distance of 350m or more in a communication area. Therefore, it can be determined that it is suitable for V2V communication.

Dual array antenna and communication system characteristics (cable length and compatibility)

19 is a diagram showing the performance of a communication system including a dual array antenna device of the present invention according to the length of a cable.

Referring to FIG. 19, when the 1×4 array antenna according to the present invention described above is used as an antenna for the interior of a C-ITS vehicle, a 2.0 m cable and a 2.5 m cable are used as an installation cable for the antenna device. This is a test to compare the communication area in case of doing. As for the test conditions, a total of ten conditions from the first test to the tenth test as shown in FIG. 8 are performed identically. As a result of the test, it can be seen that the average communication area is 353.5m when a 2.0m cable is used, and a better communication area distance can be secured than an average of 291.2m when a 2.5m longer cable is used. Therefore, the length of the connection cable between the 1×4 array antenna and the vehicle-mounted device (OBU) according to the present invention installed inside the vehicle is preferably configured as short as possible. In particular, the present invention provides an antenna located inside the vehicle. Therefore, it can be configured to be shorter than the length of the connection cable of the conventional external antenna.

FIG. 20 is a diagram showing overall test results obtained by measuring compatibility of a communication system including a dual array antenna device of the present invention.

Referring to FIG. 20, in order to determine the suitability for actual commercialization of the 1×4 array antenna, a compatibility test with an external Shark antenna is performed. The reference antenna is installed on the stationary vehicle, and the measurement antenna is installed on the traveling vehicle (or vice versa). The test method is the same as the test condition of repeatedly measuring the communication area while rotating the stationary vehicle with reference to FIGS. 15 to 18 by 45 degrees. At this time, the antenna installation position inside the vehicle was fixed to the lower part of the assistant seat (which is advantageous for securing visibility when driving) when it is installed in the front, and installed at the lower center or the lower part of the assistant seat when installed in the rear.

As a result of the test, when the antenna is installed in the front passenger seat of the vehicle, the communication area is better than that in the case where the antenna is installed in the rear of the vehicle. There was no. Therefore, as a whole, there was no significant problem in the compatibility between the 1×4 array antenna and the existing external Shark antenna.

Dual array antenna and communication system characteristics (V2I)

In the following detailed description, a round trip field test is performed from the Yuseong World Cup intersection in Daejeon, a section in which the C-ITS roadside base station is installed, to the front of Yangji Middle School in Sejong City for the vehicle-to-infrastructure (V2I) performance verification. First, a vehicle terminal and an antenna to be measured are installed in the traveling vehicle. Then, while driving, it receives V2I service from the roadside station installed on the road. Finally, it analyzes whether the correct service is provided through the HMI installed in the driving vehicle. More detailed measurement results can be understood by the following detailed description with reference to the drawings.

21 is a test screen for measuring V2I performance of a communication system including a dual array antenna device of the present invention.

22 is a diagram showing the overall test result of measuring V2I performance of a communication system including a dual array antenna device of the present invention.

21 and 22, V2I service accuracy measurement results, (a) location-based traffic information provision service, (b) road hazard section information provision service, and (c) road surface condition weather information provision service, received a 100% reception rate. Is showing. However, in both the external shark antenna and the 1×4 array antenna according to the present invention, it can be seen that some reception omissions occur in the (d) crossroad signal violation risk warning service, which is the condition of the road and the impact on the vehicle when stopping. This may be caused by external factors such as the location of the measuring antenna and the length of the cable.

The test results are as follows: (d) In the case of the crossroad signal violation risk warning service, when a 1×4 array antenna is installed in the center of the rear of the vehicle, it shows 98.9% accuracy, which is the same level as the existing external shark antenna, and is superior to other test conditions. Can be seen. Therefore, in the case of installing an antenna for the interior of the vehicle, installing it in the center when installing a 2.0m cable and the lower rear side of the vehicle can improve V2I service accuracy.

In the above, the present invention has been described with reference to the embodiments shown in the drawings. However, the present invention is not limited thereto, and various modifications or other embodiments falling within the scope equivalent to the present invention are possible by those of ordinary skill in the art. Therefore, the true scope of protection of the present invention should be determined by the following claims.

100: substrate portion 200: patch portion
210: feed line 400: power distribution unit
500: case 1000: dual array antenna device
2000: Vehicle-mounted device

Claims (14)

delete delete delete delete delete delete A substrate portion formed of a dielectric material, a patch portion formed on one surface of the substrate portion and a radiating element having a constant inclination angle by cutting a pair of corners facing each other in a diagonal direction among square corners, and formed on one surface of the substrate portion An antenna device installed inside a vehicle, comprising: a power supply line connected to and supplying electromagnetic energy, and a conductive ground portion formed on the other surface corresponding to one surface of the substrate; And
The antenna device is a vehicle-mounted device (OBU) that is connected inside the vehicle to process data signals
Including,
Of the antenna device
A plurality of the patch portions and the feed lines are arranged, and are arranged in one row and four columns at regular intervals on one surface of the substrate portion,
Further comprising a power distribution unit for differentially distributing power to each of the patch units through the feed line, wherein the power distribution unit differentially distributes power at a ratio of 0.1:0.4:0.4:0.1 to each of the patch units,
The patch portions and the power supply lines arranged in one row and four columns, and the power distribution portion for differentially distributing power to each of the patch portions are dually arranged in the vertical direction,
The antenna device and the vehicle-mounted device (OBU) are connected with an installation cable having a length of 2.0 m,
The antenna device is a communication system using an antenna device, characterized in that installed in the lower center of the rear rear of the vehicle. The method of claim 7,
Of the antenna device
A communication system using an antenna device, characterized in that the corners of the pair of patch portions have the constant inclination angles formed on the upper right side and the lower left side based on the feed line. The method of claim 8,
The inclination angle of the patch part is a communication system using an antenna device, characterized in that the ratio of the horizontal width and the vertical length is 2.2:1 based on the feed line. delete delete delete The method of claim 7,
The antenna device is an integrated module built in one case,
A communication system using an antenna device, characterized in that the case is provided with a means for displaying a telephone number. The method of claim 7,
A communication system using an antenna device, characterized in that a length of a connection cable between the antenna device installed inside the vehicle and the vehicle-mounted device (OBU) is shorter than that of an external antenna.

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