KR100862493B1 - Mobile-communication terminal - Google Patents

Abstract

A mobile communication terminal is provided to obtain a substrate with a ground pattern tuning resonance frequency when an antenna is set thereon. A mobile communication terminal includes a chip antenna and a printed circuit board. The chip antenna includes dielectric block(11), a first conductor pattern(12), a second conductor pattern(13), and a third conductor pattern(14). The dielectric block is hexahedral in shape. The first conductor pattern is formed on a side of the dielectric block and is connected to a feeding line. The second conductor pattern is formed on another side of the dielectric block and is connected to the first conductor pattern and a ground. The third conductor pattern is formed on another side of the dielectric block, has gaps from the first and second conductor patterns, and is connected to the ground. The printed circuit board has a chip antenna formed thereon and includes a tuning ground pattern connected to the ground for tuning frequency properties of the chip antenna.

Description

Mobile terminal {MOBILE-COMMUNICATION TERMINAL}

The present invention relates to a chip antenna and a mobile communication terminal including the same, and more particularly, a conductor pattern connected to a feeding part and a ground part, and a conductor pattern connected capacitively to the conductor pattern and connected to a ground part. The present invention relates to a chip antenna having a chip and a mobile communication terminal including the chip antenna.

In the mobile communication field, an antenna is a passive element whose characteristics change sensitively according to the surrounding environment, and receives an electric wave from an external station such as a base station, a repeater, or an antenna attached to a wireless communication device, or transmits an electrical signal generated from a communication device to an external device. It serves to convey.

The chip antenna embedded in the mobile communication terminal requires the optimization of characteristics such as standing wave matching for each terminal. When the bandwidth of the chip antenna is narrow, the experiments for optimizing are increased, whereas in the case of wide bandwidth, the experiment volume is reduced. Shortening is possible.

In the conventional chip antenna, a feeding structure and a radiator are designed for a specific frequency band by forming a radiation pattern connected to a feeding part and a ground part on a dielectric block. However, there have been limitations in designing such a feed structure to have broadband characteristics.

In addition, since the frequency characteristic of the antenna changes when the chip antenna is set inside the mobile communication terminal, tuning is inevitable. Such tuning involves a change in the pattern of the antenna itself or the design of the dielectric block itself, thereby resulting in manufacturing losses.

In order to solve the above problems, the present invention provides a chip antenna having a wideband frequency characteristic and having a good standing wave ratio of the antenna in the frequency band and a ground pattern capable of tuning the resonance frequency when the antenna is set inside the mobile communication terminal. An object of the present invention is to provide a mobile communication terminal including a substrate having a substrate.

One surface of the present invention includes a dielectric block having an upper surface and a lower surface facing each other, a plurality of side surfaces connecting the upper surface and the lower surface, and a first conductor pattern formed on at least one surface of the dielectric block and connected to an external feeder. And a second conductor pattern formed on at least one surface of the dielectric block so as to be connected to the first conductor pattern, one end of which is connected to an external ground portion, and formed on at least one surface of the dielectric block. A chip antenna may be provided with a third conductor pattern spaced apart from two conductor patterns by a predetermined distance, respectively, to form capacitive coupling with the first and second conductor patterns, and one end of which is connected to an external ground.

The dielectric block may be a rectangular parallelepiped.

The first conductor pattern and the second conductor pattern form one radiator, and the radiator has a first side surface, an upper surface parallel to the longitudinal direction of the dielectric block, and a second side surface opposite to the first side surface. Can be formed over.

The first conductor pattern may be formed on a first side surface parallel to the length direction of the dielectric block.

The first conductor pattern may be formed such that one end thereof is in contact with a line where the first side surface and the top surface of the dielectric block cross each other, and in this case, the first conductor pattern may have a L shape.

The second conductor pattern may be formed on a second side surface and an upper surface of the dielectric block facing the first side surface of the dielectric block.

The second conductor pattern may include a connecting portion contacting the first conductor pattern by a predetermined length, and an area except the connecting portion may be formed to be spaced apart from the first conductor pattern by a predetermined distance.

The third conductor pattern may be formed on a lower surface of the dielectric block, wherein the third conductor pattern is formed so that one end is in contact with a line where the lower surface and the first side surface of the dielectric block cross each other. It may have one bent portion.

The first conductor pattern may be formed on a first side surface of the dielectric block, and may have an L shape formed at an end portion thereof in contact with a line where the first side surface and the top surface of the dielectric block intersect each other. Except for a partial region connected to the first conductor pattern, the dielectric block is formed so as to be spaced apart from a line intersecting the upper surface and the first side surface by a predetermined distance, and the third conductor pattern is formed on the lower surface of the dielectric block. The first and second ends of the dielectric block may be in contact with a line crossing the first and second side surfaces of the dielectric block, and may have at least one bent portion.

In another aspect of the present invention, there is provided a dielectric block having an upper surface and a lower surface facing each other, a plurality of side surfaces connecting the upper surface and the lower surface, and a second block formed on at least one surface of the dielectric block and connected to an external power supply unit. A first conductor pattern, a second conductor pattern formed on at least one surface of the dielectric block so as to be connected to the first conductor pattern, and one end of which is formed on at least one surface of the dielectric block; A chip antenna comprising a third conductor pattern having a capacitive coupling with the first and second conductor patterns respectively spaced apart from the first and second conductor patterns by a predetermined distance, and having one end connected to an external ground; A chip antenna is mounted and has a tuning ground pattern, one end of which is connected to a ground portion, for use in tuning the frequency characteristic of the chip antenna on a surface opposite the one surface. Provided is a mobile communication terminal including a printed circuit board.

The tuning ground pattern may have a c-shape formed along a border of an area corresponding to a mounting area of the chip antenna.

The tuning ground pattern may be displayed with a ruler to facilitate tuning.

According to the present invention, it is possible to obtain a chip antenna that exhibits broadband characteristics and good antenna characteristics in the band, and when the chip antenna and the chip antenna are set in a mobile communication terminal, the frequency characteristics of the antenna can be easily tuned. It is possible to obtain a mobile communication terminal including a substrate which can be used.

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

1A and 1B are a perspective view and a developed view of a chip antenna according to an embodiment of the present invention.

Referring to FIGS. 1A and 1B, a chip antenna according to an exemplary embodiment of the present invention may include a dielectric block 11, a first conductor pattern 12, a second conductor pattern 13, and a third antenna. The conductor pattern 14 may be included.

The dielectric block 11 may have a rectangular parallelepiped shape. The dielectric block 11 has upper and lower surfaces 11a and 11b facing each other, and first to fourth side surfaces 11c, 11d, 11e and 11f connecting the upper and lower surfaces 11a and 11b. Can have The lower surface 11b of the dielectric block may be a surface contacting the substrate when the antenna is mounted on the substrate.

The first conductor pattern 12 and the second conductor pattern 13 are connected to each other on the first side surface 11c, the top surface 11a, and the second side surface 11d of the dielectric block 11 to form one radiator. Can be formed.

One end of the first conductor pattern 12 may be connected to an external feeder to supply a signal to the radiator. The second conductor pattern 13 may be connected to the first conductor pattern 12, and one end thereof may be connected to an external ground portion. A partial region 13a of the second conductor pattern may be a connection with the first conductor pattern 12. The first conductor pattern 12 and the second conductor pattern 13 may act as radiators of the antenna.

In order to maximize the use of the outer area of the dielectric block having a rectangular parallelepiped, the radiators formed by the first conductor pattern 12 and the second conductor pattern 13 are formed on the first side surface 11c and the top surface 11a of the dielectric block. ) And the second side face 11d.

In the present embodiment, the first conductor pattern 12 is formed on the first side surface 11c parallel to the longitudinal direction of the dielectric block, and the second conductor pattern 13 is the second side surface 11d of the dielectric block. ) And the upper surface 11a.

The first conductor pattern 12 has a L-shape, and the first conductor pattern 12 is spaced apart from the ground portion on the substrate on which the chip antenna is mounted by a part of the first conductor pattern 12. One end of) may be connected to an external feeder. A partial region of the first conductor pattern 12 may be formed to be in contact with the line connecting the first side surface 11c and the top surface 11a of the dielectric block.

Accordingly, the first conductor pattern 12 and the second conductor pattern 13 serve as radiators of the antenna, while the third conductor pattern 14 is formed by capacitive coupling with the first and second conductor patterns. It can serve to change the impedance characteristics of the. The strength of the capacitive coupling can be controlled by the spacing or adjacent area between the conductor patterns.

In the present embodiment, the shape of the first conductor pattern 12 is a-shape, and the end portion thereof is formed to be in contact with the line where the first side surface 11c and the top surface 11a of the dielectric block intersect. And for adjusting the size of the capacitive coupling between the second conductor pattern and the third conductor pattern.

The second conductor pattern 13 may be formed to extend on the second side surface 11d and the upper surface 11a of the dielectric block 11. A portion of the second conductor pattern formed on the second side 11d of the dielectric block 11 may have a shape corresponding to the first conductor pattern 12. In addition, in the second conductor pattern formed on the top surface 11a of the dielectric block 11, the portion 13a connected to the first conductor pattern 12 may have a first side surface 11c of the dielectric block 11. ) And the upper surface 11a may extend to a line connecting the first surface 11a and the upper surface 11a of the dielectric block 11 except for the portion 13a connected to the first conductor pattern 12. The line 11a may be spaced apart from each other by a predetermined interval. The width of the second conductor pattern 13 may be formed to correspond to the width of the first conductor pattern 12.

The width of the portion 13a to which the second conductor pattern 13 and the first conductor pattern 12 are connected may also be variously formed, and the portion where the connecting portion 13a and the first conductor pattern 12 contact each other. The characteristics of the antenna can be changed depending on the length of the antenna.

One end of the first conductor pattern 12 may be connected to a feeder to receive a signal from the outside, and one end of the second conductor pattern 13 may be connected to a ground.

The signal input from the outside flows to the second conductor pattern 13 connected to the first conductor pattern 12, so that the first conductor pattern 12 and the second conductor pattern 13 serve as radiators of the antenna. Can work.

The first conductor pattern and the second conductor pattern may be implemented in various forms as long as they are formed on three surfaces of the rectangular dielectric block. That is, the connecting portion 13a may be formed in the first conductor pattern and the second conductor pattern at the first side surface 11c or the second side surface 11d of the dielectric block.

A third conductor pattern 14 may be formed on the bottom surface 11b of the dielectric block 11, and one end of the third conductor pattern 14 may be connected to an external ground portion.

The third conductor pattern 14 is capacitively coupled with the first conductor pattern 12 and the second conductor pattern 13 to match the impedance of the antenna.

The third conductor pattern 14 may adjust impedance matching of the entire antenna by adjusting its length. That is, as the length of the third conductor pattern 14 is shortened, the resonance frequency of the antenna may be changed to high frequency, and when the length of the third conductor pattern 14 is long, the resonance frequency of the antenna may be changed to low frequency.

Preferably, the third conductor pattern 14 may be formed such that one end thereof is in contact with a line where the lower surface 11b and the first side surface 11c of the dielectric block cross each other, and to secure a predetermined length. At least one bent portion may be formed.

2 (a) and 2 (b) are graphs showing standing wave ratios and Smith charts of the chip antenna according to the embodiment of the present invention shown in FIG.

In the graph of Fig. 2A, the x axis represents frequency (MHz) and the y axis represents standing wave ratio (SWR).

Here, the standing wave ratio represents the ratio between the output to the antenna and the output to be returned. The standing wave ratio is an optimum condition of 1, which is a state in which there is no reflected wave, and when the standing wave ratio is 3 or more, it is difficult to show characteristics as an antenna.

In this embodiment, a chip antenna in which the first to third conductor patterns are formed on a ceramic dielectric block of 6x2x1.5 [mm] is mounted on a test PCB made of FR4 material of 40x40x1.0 [mm]. The standing wave ratio was measured.

As shown in (a) of FIG. 2, the standing wave ratio in this embodiment is that the standing wave ratio is 3 or less within the range of about 2160 to 2280 [MHz], and a bandwidth of about 120 [MHz] is obtained. The standing wave ratio is excellent within the range. The frequency at the point A with the best standing wave ratio is the resonant frequency, which is about 2220 [MHz] in this embodiment.

In the embodiment shown in FIG. 1, in the case of the antenna without the third conductor pattern 14, the standing wave ratio characteristics will be worse than in the present embodiment. That is, the curve of the standing wave ratio is moved upward as a whole, so that the band of the frequency at the same standing wave ratio will be narrower than in the present embodiment.

In this embodiment, by forming a third conductor pattern capacitively coupled with the radiation pattern of the antenna to facilitate impedance matching of the entire antenna, it is possible to implement a chip antenna having good antenna characteristics in the band while exhibiting broadband characteristics.

2B shows a Smith chart for the chip antenna. In the Smith chart, the larger the impedance circle is formed, the less the influence of the ground condition of the substrate on which the chip antenna is mounted may appear. In this embodiment, it can be seen that the impedance circle of the chip antenna is located near 50 kHz at the resonance frequency (A).

3A and 3B are a perspective view and a rear view of a substrate on which a tuning ground pattern included in a mobile communication terminal according to another embodiment of the present invention is formed.

Referring to FIGS. 3A and 3B, the substrate 35 on which the chip antenna is mounted may include a dielectric layer 35c such as FR4 and ground portions 35a and 35b formed on both surfaces of the dielectric layer. have. The ground portions 35a and 35b may be connected to each other through a plurality of via holes 36.

A chip antenna 10 may be mounted on one surface of the substrate, and the chip antenna 10 may be formed on the dielectric layer 35c on which the ground portion 35a is not formed.

The chip antenna 10 is the chip antenna shown in FIG. 1, and the first conductor pattern of the chip antenna is supplied with a signal by the feeding part 32 on the substrate, and the second conductor pattern and the third conductor pattern are respectively. It may be connected to the ground portion 35a by lines 33 and 34.

On the rear surface of the surface on which the chip antenna 10 is mounted, the ground portion 35b is not formed at a portion corresponding to the mounting surface of the chip antenna, and the dielectric layer 35c is directly exposed. . A ground pattern 38 may be formed along an edge portion of a region of the exposed dielectric layer 35c corresponding to the mounting surface of the chip antenna. One end of the ground pattern 38 may be connected to the ground part 35b.

The ground pattern 38 may have at least one bent portion to maintain a predetermined length. The ground pattern 38 may be capacitively coupled to the radiator of the chip antenna 10 mounted on the opposite surface of the substrate 35 to change the frequency characteristic of the antenna according to the length of the ground pattern 38.

In this embodiment, a c-shaped ground pattern 38 whose one end is connected to the ground portion 35b is formed along the edge portion of the region corresponding to the mounting surface of the chip antenna mounted on the substrate. In order to adjust the length of the ground pattern may be partially cut from the open end of the ground pattern.

Preferably, a ruler may be formed on the ground pattern to facilitate tuning of the ground pattern. In this embodiment, rulers were formed at intervals of 1 mm.

By using the ground pattern 38, it is possible to facilitate tuning of the frequency characteristics required when the substrate on which the chip antenna 10 is mounted is set inside the mobile communication terminal. That is, the resonance frequency of the chip antenna 10 may be changed by adjusting the length of the ground pattern 38 without redesigning the conductor pattern or the dielectric block formed on the chip antenna 10.

4 is a graph illustrating a change in antenna characteristics according to a change in length of a tuning ground pattern in the mobile communication terminal of FIG.

In this embodiment, a chip antenna having the first to third conductor patterns formed on a ceramic dielectric block of 6x2x1.5 [mm] is mounted on a test substrate of FR4 material of 40x40x1.0 [mm]. After mounting, a tuning ground pattern having a length of 15 mm was formed on the rear surface of the substrate, and the resonance frequency of the antenna was changed as the length of the tuning ground pattern was gradually reduced.

Referring to FIG. 4, it can be seen that the resonance frequency of the antenna is changed according to the length of the tuning ground pattern.

That is, when the length of the tuning ground pattern is 8 mm (D), the resonant frequency is about 2.8 Hz, and when 6 mm is about 2.55 Hz (C), and when 4 mm is about 2.4 Hz (B), 0 mm It can be seen that the resonance frequency of about 2.25 Hz (A) is shown. By these experimental values, in this embodiment, the frequency of about 65 MHz per 1 mm of the tuning ground pattern is changed. As described above, according to the present embodiment, the cover of the 2 GHz frequency band incorporated in the terminal can be covered with only one chip antenna. Therefore, it can be used as ISM frequency band and chip antenna for S-DMB.

In addition, the resonance frequency of the antenna is changed according to the change in the length of the tuning ground pattern, but the standing wave ratio is kept constant.

Although not shown in the drawings, the gain and the radiation pattern for the present embodiment exhibit an average gain of -3 dBi or more at 84 MHz bandwidth centered on the resonance frequency before and after removing the ground pattern.

As such, the present invention is not limited by the above-described embodiment and the accompanying drawings. That is, the shape of the dielectric block, the shape and arrangement of the conductor patterns, and the like may be variously implemented. It is intended that the scope of the invention be defined by the appended claims, and that various forms of substitution, modification, and alteration are possible without departing from the spirit of the invention as set forth in the claims. Will be self-explanatory.

1 (a) and 1 (b) are a perspective view and a developed view of an embodiment of a chip antenna which is one surface of the present invention.

2A and 2B are standing wave ratio characteristics and a Smith chart graph of the chip antenna of FIG.

3A and 3B are a perspective view and a rear view of a substrate on which a tuning ground pattern included in a mobile communication terminal according to another embodiment of the present invention is formed.

4 is a graph illustrating a change in antenna characteristics according to a change in length of a tuning ground pattern in the mobile communication terminal of FIG. 3.

<Description of Signs of Major Parts of Drawings>

11: dielectric block 12: first conductor pattern

13: second conductor pattern 14: third conductor pattern

35 substrate 36 via hole

Claims (13)

A dielectric block having an upper surface and a lower surface facing each other, a plurality of side surfaces connecting the upper surface and the lower surface, a first conductor pattern formed on at least one surface of the dielectric block and connected to an external feeder, and the first conductor A second conductor pattern formed on at least one surface of the dielectric block so as to be connected to the pattern, and one end of which is connected to an external ground portion, and formed on at least one surface of the dielectric block, and having a predetermined distance from the first and second conductor patterns A chip antenna spaced apart from each other to form a capacitive coupling with the first and second conductor patterns, the third antenna pattern having one end connected to an external ground portion; And A printed circuit board having a tuning ground pattern having a chip antenna mounted on one surface thereof and having a tuning ground pattern having one end connected to a ground portion so as to be used to tune the frequency characteristic of the chip antenna on a surface opposite the surface on which the chip antenna is mounted. Mobile communication terminal comprising a. The method of claim 1, The tuning ground pattern is, And a c-shape formed along an edge of an area corresponding to the mounting area of the chip antenna. The method of claim 2, The tuning ground pattern is, Mobile communication terminal characterized in that the ruler is displayed to facilitate tuning. The method of claim 1, The dielectric block is a mobile communication terminal, characterized in that the rectangular parallelepiped. The method of claim 4, wherein One radiator is formed by connecting the first conductor pattern and the second conductor pattern, and the radiator is And a first side surface, an upper surface parallel to the length direction of the dielectric block, and a second side surface facing the first side surface. The method of claim 5, The first conductor pattern, And a first side surface parallel to the length direction of the dielectric block. The method of claim 6, The first conductor pattern, And one end thereof is in contact with a line where the first side surface and the top surface of the dielectric block intersect each other. The method of claim 7, wherein The first conductor pattern, Mobile communication terminal, characterized in that the a-shaped. The method of claim 5, The second conductor pattern is, And a second side surface and an upper side surface facing the first side surface of the dielectric block. The method of claim 9, The second conductor pattern is, It includes a connecting portion in contact with the first conductor pattern in a predetermined length, The area excluding the connection part is formed so as to be spaced apart from the first conductor pattern by a predetermined interval. The method of claim 5, The third conductor pattern, A mobile communication terminal, characterized in that formed on the lower surface of the dielectric block. The method of claim 11, The third conductor pattern is, And one end contacting a line crossing the lower surface and the first side surface of the dielectric block, and having at least one bent portion. The method of claim 5, The tuning ground pattern has a c-shape formed along an edge of an area corresponding to a mounting area of the chip antenna. The first conductor pattern is formed on the first side surface of the dielectric block, and has an L-shape formed so that an end portion thereof is in contact with a line where the first side surface and the upper surface of the dielectric block intersect. The second conductor pattern is formed to be spaced apart from a line where the upper surface and the first side surface of the dielectric block intersect, except for a partial region connected to the first conductor pattern, The third conductor pattern is formed on a lower surface of the dielectric block, and has one end contacting a line intersecting the lower surface and the first side surface of the dielectric block, and having at least one bent portion. .

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