KR101265096B1 - Antenna apparatus and vehicle having the same - Google Patents

Abstract

PURPOSE: An antenna device and a moving body including the same are provided to efficiently use a space by using one antenna. CONSTITUTION: A dielectric substrate includes a ground(120) in one side. A first conduction member(130) is laminated on one side of the substrate. A second conduction member(140) is connected by the first conduction member and a first switch. A third conduction member is formed in the other side of the substrate. The third conduction member is mutually connected in the second conduction member by a via hole.

Description

ANTENNA APPARATUS AND VEHICLE HAVING THE SAME

One embodiment of the present invention relates to an antenna device for transmitting and receiving a wireless signal and a mobile device having the same.

With the development of mobile wireless internet technology, the demand for the use of wireless internet is not limited to time and place. Recently, the technology for embedding the terminal inside the vehicle to enable stable wireless internet access while driving It is studied a lot.

Mobile Internet technologies include WiFi, HSDPA, WiBro, and LTE, but considering the vehicle's moving speed and data rate, one mobile Internet technology does not establish a seamless vehicle wireless Internet environment.

In order to solve these drawbacks, it is possible to maximize the data rate by using multiple mobile internets according to the vehicle speed, but it is not easy to install it in the limited space of the vehicle due to the need for multiple antennas. If it is applied to, the number of antennas increases rapidly, so it is impossible to implement.

In addition, since the antenna efficiency characteristics deteriorate when the multiband antenna is designed, the service frequency band cannot be guaranteed with one antenna.

Therefore, a method of realizing various frequency characteristics without distortion of an antenna using a limited space of a vehicle may be considered.

An object of the present invention is to provide an antenna that can operate in a multi-frequency band of a different type than the conventional.

Another object of the present invention is to provide a moving body having an antenna device with improved performance.

In order to achieve the above object of the present invention, an antenna device according to an embodiment of the present invention is a dielectric substrate having a ground on one side, the first conductive member and the first conductive layer laminated on one surface of the dielectric substrate And a second conductive member connected by the member and the first switch.

According to an example related to the present invention, the first conductive member extends in a first direction after being extended in a first direction from a power feeding portion connected to the ground and is bent in a second direction, and is bent to extend toward the ground. A closed surface defined by the first conductive member may be formed.

According to an example related to the present disclosure, the semiconductor substrate may further include a third conductive member formed on the other surface of the dielectric substrate, wherein the third conductive member may include a via hole in the first conductive member or the second conductive member. May be connected to each other by

According to an example related to the present disclosure, the third conductive member may include a first member extending in parallel with the first conductive member in a first direction, and the first conductive member to partition the closed surface when projected onto the one surface. The member may include a second member extending in the second direction.

According to an example related to the present disclosure, each end of the third conductive member may be connected to each other by a via hole in the first member or the second member, respectively.

According to an example associated with the present disclosure, the apparatus may further include switches that are switched to form one path through each conductive member by being turned on or off in proximity to the respective ends.

According to an example related to the present invention, the path may include a first path passing through the first conductive member from the feed connection part, a second path passing through the first and second conductive members from the feed connection part, or the power supply. It may be any one of the third paths from the connection portion via the first to third conductive members.

According to an example related to the present invention, the dielectric substrate may include at least one of FR4, Polyacrylate, or glass.

In order to achieve the above object, another embodiment of the present invention includes a mobile device having a window and an antenna device formed in the window to transmit and receive a radio signal, the antenna device, a dielectric having a ground on one side A first conductive member stacked on one surface of the dielectric substrate, a second conductive member connected by the first conductive member and a first switch, and a third conductive member formed on the other surface of the dielectric substrate. The third conductive member discloses a movable body connected to each other by a via hole in the first conductive member or the second conductive member.

According to an example related to the present disclosure, the electronic device may further include switches that are switched to form one path through each conductive member by being turned on or off in proximity to each end of the third conductive member.

An antenna device according to at least one embodiment of the present invention configured as described above may implement three different RF feed units using an RF switch to use different frequency services without changing the physical size of the antenna. It is possible to design a thin film antenna.

In addition, by using one antenna, it is possible to efficiently use a limited space and to implement an antenna having excellent performance.

FIG. 1A is a diagram illustrating a method of reconfiguring a matching circuit using an RF switch according to an embodiment of the present invention, and FIGS. 1B to 1D illustrate an example of implementing three different matching circuits with respect to FIG. 1A. A conceptual diagram illustrating Direct matching (Mode 1), T-matching (Mode 2), and Parallel T-matching (Mode 3), respectively.
2A is a conceptual diagram of an antenna device according to an embodiment of the present invention, and FIGS. 2B to 2D are diagrams showing examples of modifying an antenna structure to three modes by adjusting an ON-OFF state of an RF switch.
Figure 3a is a DC equivalent circuit related to embodiments of the present invention, Figures 3b to 3d are diagrams showing the current distribution induced in the antenna line by the ON-OFF state of the RF switch according to each mode.
4A and 4B are views illustrating positions of a feed line and a chip inductor when the DC feed unit is mounted on the upper and lower plates of the antenna in the present invention, and FIG. 4C is a reflection coefficient according to the distance between the feed line and the proposed antenna. Graph showing the change in characteristics.
5A to 5C are graphs comparing the return loss of the reconstructed antenna using different matching circuits according to the embodiments of the present invention with simulation results and measurement results.
6A to 6C are graphs comparing azimuth radiation patterns of reconstructed antennas using different matching circuits to simulation results and measurement results in accordance with embodiments of the present invention. FIG. 6C shows the azimuth radiation pattern at 2.35 GHz. FIG.
7A is a conceptual diagram illustrating an RF equivalent circuit according to an operating principle of an antenna in accordance with an embodiment of the present invention, and FIGS. 7B to 7D are graphs comparing input impedance and EM simulation results in respective modes.
FIG. 8A is a graph illustrating reception outputs in Line-Of-Sight (LOS) and Non-Line-Of-Sight (NLOS) according to each mode of the reconfigured antenna proposed in the present invention. FIG. 8B is a graph of the NLOS (2.1 GHz) in FIG. Fig. 8C is a graph showing the reception output of the proposed antenna and the λ / 4 monopole antenna, and Fig. 8C shows the reception output of the proposed antenna and the λ / 4 monopole antenna at the LOS (2.1 GHz).

Hereinafter, an antenna device and a moving body having the same according to the present invention will be described in detail with reference to the accompanying drawings. The suffix "module" and " part "for the components used in the following description are given or mixed in consideration of ease of specification, and do not have their own meaning or role. In the present specification, the same or similar reference numerals are given to different embodiments in the same or similar configurations. As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise.

Embodiments of the present invention may be applied to a window antenna of a moving object such as a vehicle or an aircraft. That is, the antenna device according to an embodiment of the present invention may be mounted on a window of a vehicle or an aircraft.

According to embodiments of the present invention, a pin diode serving as an RF switch may be inserted into one antenna to provide a reconfigurable antenna that may serve as multiple antennas by using a potential difference of DC voltage.

Therefore, unlike the reconfigured antenna that adjusts the electrical length of the antenna by using a conventional RF switch, it is possible to implement broadband characteristics without changing the size of the reconfigured antenna by inserting and adjusting a matching circuit.

Such an antenna may be formed by, for example, printing a matching circuit on an upper plate and a lower plate with a thin polyacrylate therebetween.

In addition, four pin diodes operating as RF switches are mounted on the upper and lower plates, respectively, to facilitate switching to different matching circuits.

By adjusting the pin diode, direct-matching (Mode 1) without matching circuit, T-matching (Mode 2) with matching circuit, and parallel T-matching (Mode 3) are realized and can be applied to various shapes of radiators. .

At this time, it is necessary to design DC feeder to selectively operate pin diode, which should minimize the effect on the antenna line.

Therefore, the antenna using the reconstruction matching circuit according to the embodiment of the present invention converts the matching circuit to direct-matching, T-matching, and parallel T-matching using an RF switch, not a change in the electrical length of the radiator, so that the physical size of the antenna is changed. Various frequency characteristics and widebands can be realized without changing.

Hereinafter, with reference to the accompanying drawings will be described in more detail the present invention.

FIG. 1A is a diagram illustrating a method of reconfiguring a matching circuit using an RF switch according to an embodiment of the present invention, and FIGS. 1B to 1D illustrate an example of implementing three different matching circuits with respect to FIG. 1A. As a figure, it is a conceptual diagram which shows Direct matching (Mode 1), T-matching (Mode 2), and Parallel T-matching (Mode 3), respectively.

1A is an equivalent circuit diagram illustrating an operation principle of an antenna using a reconstruction matching circuit used in the present invention.

As shown in FIG. 1A, four RF switches were used in a circuit of parallel T-matching. In the equivalent circuit, when all the RF switches are in the OFF state, the power supply of the antenna corresponds to mode 1 as direct matching. And, when only one RF switch is in the ON state, it corresponds to mode 2 as T-matching. Finally, parallel T-matching corresponds to mode 3 when all RF switches are in the ON state.

2A is a conceptual diagram of an antenna device according to an embodiment of the present invention, and FIGS. 2B to 2D are diagrams illustrating examples of modifying an antenna structure to three modes by adjusting an ON-OFF state of an RF switch.

An antenna device according to an embodiment of the present invention includes a dielectric substrate 110 having a ground 120 and conductive members 130, 140, and 150 stacked thereon, respectively.

The first conductive member 130 and the second conductive member 140 may be formed on the first surface 111, that is, the upper surface. The third conductive member 150 may be formed on the rear surface of the second surface 112.

When the third conductive member 150 is projected onto the first member 111 extending in parallel with the first conductive member 130 in the first direction and the first surface 111 of the substrate, the third conductive member 150 divides the closed surface. The first member 151 may include a second member 152 extending in the second direction.

The first and second conductive members 130 and 140 and the third conductive member 150 may be connected to each other through a via hole 113 penetrating through the dielectric substrate 110.

The first to third conductive members 130, 140, and 150 may operate as radiators formed to resonate in a predetermined frequency band.

The first and second conductive members 130 and 140 formed on the first surface 111 may operate as a T-matching circuit, and the third conductive member 150 formed on the second surface 112 may have another T. Can be a matching circuit

The dielectric substrate 110 may be, for example, a thin polyacrylate (2 mm thick, ε _r = 3.25, tan δ = 0.016) substrate. In addition, any one of FR4 and glass may be used as the dielectric substrate 110. Among these, FR4 means that the glass fiber impregnated with epoxy resin was overlapped in several layers.

The ground 120 may be formed at one side of the dielectric substrate 110, and the ground 120 and the first conductive member 130 may be electrically connected to each other by a power feeding unit.

The first conductive member 130 may be formed in a 'c' shape. That is, it extends in the first direction from the feed section and is bent to extend in the second direction, and is bent again to extend toward the ground 120. As illustrated in FIG. 2A, the first conductive member 130 and the ground 120 may form a rectangular closed surface.

The first conductive member 130 and the second conductive member 140 may be connected to each other by an RF switch. In addition, an RF switch is formed at each end of the third conductive member 150, and a via hole to which the first and second conductive members 130 and 140 and the third conductive member 150 are connected in proximity to the RF switch is provided. Can be formed.

 As the RF switches 161, 162, 163, and 164, for example, a pin diode may be used. At this time, the antenna device operates in three modes according to the ON-OFF state of the pin diode.

That is, the first mode operates as a folded monopole without a matching circuit when all the switches are in an OFF state, and the second mode is a monopole having a T-matching circuit when only the first switch 161 is in an ON state. Then, when all the switches are in the ON state, the third mode is a monopole having a parallel T-matching circuit. The first to third modes are modes that operate in any one frequency band of 900 MHz, 2.1 GHz, and 2.3 GHz, respectively.

For example, the antenna device has a first path from the power supply connection part via the first conductive member 130 when all the switches are in the OFF state, and thus resonates in the 900 MHz band (first mode). When only the first switch is in the ON state, the second switch has a second path from the power supply connection part via the first and second conductive members 130 and 140 and thus resonates in the 2.1 GHz band (second mode). In addition, when all the switches are in the ON state, a third path is passed from the power supply connection part via the first to third conductive members 130, 140, and 150, thereby resonating in the 2.3 GHz band (third mode).

3A is a diagram showing a DC equivalent circuit related to embodiments of the present invention, and FIGS. 3B to 3D are diagrams showing current distribution induced in an antenna line by an ON-OFF state of an RF switch according to each mode.

3A is a DC equivalent circuit for deriving a DC feeding position according to reconfiguration of a matching circuit. As it can be seen through Figures 3b to 3d, it was confirmed through the simulation that the current is less than -30 dBA in the line blocked by the pin diode in mode 1, mode 2, mode 3, respectively, and the RF signal will be blocked correctly It can be seen that.

4A and 4B are views illustrating positions of a feed line and a chip inductor when the DC feed unit is mounted on the upper and lower plates of the antenna in the present invention, and FIG. 4C is a reflection coefficient according to the distance between the feed line and the proposed antenna. It is a graph showing the change of characteristics.

4 is a diagram illustrating a design of a DC power supply unit for operating a reconstruction matching circuit according to the present invention, and FIGS. 4A and 4B show a feed line for operating modes 2 and 3. Figure 4c is a comparison of the characteristics of the antenna according to the distance (X mm) of the proposed antenna and the feed line, it can be seen that there is little effect between each other when the distance between the antenna and the DC feed line is 5 mm or more.

In addition, the effect of the designed antenna should be minimized when implementing the DC feed part to control the RF switch, and a chip inductor may be inserted to block the distortion of the RF signal by the DC voltage.

5A to 5C are graphs comparing the return loss of a reconstructed antenna using different matching circuits according to embodiments of the present invention with simulation results and measurement results.

FIG. 5 is a diagram comparing reflection simulation with EM simulation by measuring a thin film type antenna using a reconstruction matching circuit according to the present invention on a rear portion of a rear surface of a commercial sedan. As shown in FIG. 5A, 21% based on -3 dB return loss in the 900 MHz (mode 1) band, 20.7% in the 2.1 GHz (mode2) band as shown in FIG. 5B, and as shown in FIG. 5C. In the 2.3 GHz (mode3) band, it can be seen that it has a 25.2% half power bandwidth.

6A to 6C are graphs comparing azimuth radiation patterns of reconstructed antennas using different matching circuits with simulation results and measurement results in accordance with embodiments of the present invention. 6 GHz and FIG. 6C illustrate azimuth radiation patterns at 2.35 GHz.

6A to 6C are diagrams showing simulation and measurement results of the azimuth radiation gain in each mode according to the embodiments of the present invention. The average radiation gain from the measurement is -6.5 dBi, 2.1 at 900 MHz (mode 1). It can be seen that it is -7.0 dBi at GHz (mode2) and -3.9 dBi at 2.3 GHz (mode3), which is in good agreement with the simulation.

In other words, when the antenna designed according to the embodiments of the present invention is mounted on a commercially available sedan, it can be seen that more than 20% of a fractional bandwidth and an average radiation radiation of -8 dBi or more can be maintained for each mode. .

In addition, even though the characteristics of the azimuth radiation gain are distorted due to the influence of the vehicle frame, it can be seen that the omnidirectional radiation characteristics can be realized around 20 dB.

7A is a conceptual diagram illustrating an RF equivalent circuit according to an operation principle of an antenna in accordance with an embodiment of the present invention, and FIGS. 7B to 7D are graphs comparing input impedance and EM simulation results in respective modes.

7 shows the input impedance values derived from the RF equivalent circuit model and the EM simulation. As shown, the input impedance according to the mode of the reconstructed matching circuit antenna is derived by the switch in the RF equivalent circuit model, and the resistance component of less than 100 Ω and the reactance component between -200 Ω and 200 Ω at the center frequency of each mode are obtained. It can be seen that it is advantageous to the broadband matching of the antenna.

FIG. 8A is a graph illustrating reception outputs in Line-Of-Sight (LOS) and Non-Line-Of-Sight (NLOS) according to each mode of the reconfigured antenna proposed in the present invention. FIG. 8B is a graph of the NLOS (2.1 GHz) A graph showing the reception output of the proposed antenna and the λ / 4 monopole antenna, and FIG. 8C is a graph showing the reception output of the proposed antenna and the λ / 4 monopole antenna at the LOS (2.1 GHz).

8 is a spectrum analyzer in a strong electric field (one of Sangam-dong, Mapo-gu, Seoul) and a weak field (one of constant water-dong, Mapo-gu, Seoul) after mounting on the rear glass of the actual sedan vehicle to verify the reception output of the thin-film antenna using the reconstruction matching circuit according to the present invention. This is a graph comparing the λ / 4 monopole antenna with the reception power measured using (Aglient 8593A). (a) shows the measurement result and the average receiving power is -72.97 dBm (mode1), -73.96 dBm (mode2), -72.78 dBm (mode3) in weak field and -67.76 dBm (mode1) and -64.22 dBm in strong field mode2), -63.02 dBm (mode3). (B) shows that the average reception power of the λ / 4 monopole antenna in the 2.3 GHz band (mode3) is similar to the thin-film antenna using the reconstruction matching circuit proposed at -68.3 dBm in the weak field and -55.4 dBm in the strong field. This can be confirmed through (c).

In other words, it can be seen that the performance is maintained similar to that of the antenna when the reception power is measured in the strong field and the weak field.

The above-described antenna device and the movable body having the same are not limited to the configuration and method of the above-described embodiments, but the embodiments are all or part of each of the embodiments so that various modifications can be made. It may be configured in combination.

Claims (10)

A dielectric substrate having ground on one side;
A first conductive member laminated on one surface of the dielectric substrate;
A second conductive member connected to the first conductive member by a first switch; And
A third conductive member formed on the other surface of the dielectric substrate and connected to each other by a via hole in the first conductive member or the second conductive member;
The first conductive member,
Extends in a first direction from a feed section connected to the ground to the ground and is bent to extend in a second direction, and is bent again to the ground to form a closed surface defined by the first conductive member; ,
The third conductive member,
A first member extending in parallel with the first conductive member in a first direction; And
And a second member extending from the first member in the second direction so as to partition the closed surface when projected onto the one surface. delete delete delete The method of claim 1,
Each end of the third conductive member is connected to each other by a via hole in the first member or the second member, respectively. The method of claim 5,
In close proximity to each end,
And on / off controlled switches to be switched to form either path via each conductive member. The method according to claim 6,
The route is,
A first path passing through the first conductive member from the feed connection part, a second path passing through the first and second conductive members from the power supply connection part, or via the first through third conductive members from the feed connection part; The antenna device, characterized in that any one of the third path. The method of claim 1,
The dielectric substrate,
An antenna device comprising at least one of FR4, Polyacrylate or glass. A movable body having a window; And
A movable body formed in the window to transmit and receive a radio signal, comprising an antenna device according to claim 1. 10. The method of claim 9,
In proximity to each end of the third conductive member,
And on / off controlled switches to be switched to form either path via each conductive member.

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