KR20080078149A - Internal antenna - Google Patents

Abstract

An internal antenna is provided to obtain a desired characteristic by controlling impedance without changing a shape of a radiator pattern or dielectric material. An internal antenna includes an upper dielectric block, a lower dielectric block(300), and an intermediate dielectric block. The upper dielectric block has first radiator patterns. The second dielectric block has a second radiator pattern(390). The intermediate dielectric block has at least one vertically perforated air gap and is interposed between the upper and lower dielectric blocks to connect the first and second radiator patterns electrically through via holes. The lower dielectric block has a conductive feed pad(380) and a ground pad(370). The feed pad and the ground pad are spaced apart from each other and electrically connected to the first radiator patterns through the via holes of the intermediate dielectric block.

Description

 Internal antenna

1 is a view showing a built-in antenna according to the prior art.

2 is an exploded perspective view of a built-in antenna according to an embodiment of the present invention.

3 is a state diagram of the combination of portion "A" of FIG.

FIG. 4 is a state diagram of coupling of the portion “B” of FIG. 2.

FIG. 5 is a coupling state diagram of part “C” of FIG. 2.

6 is a state diagram of FIG.

<Description of the symbols for the main parts of the drawings>

100: upper dielectric block 120: upper radiator pattern

130: first lower radiator pattern 140: second lower radiator pattern

200: multilayer dielectric block 295a, 295b: air gap

300: lower dielectric block 370: ground pad

380: feeding pad 390: second radiation pattern

The present invention relates to a built-in antenna of a mobile communication terminal, and more particularly, to form a dielectric block having a multi-layer structure, an air gap is formed between the dielectric blocks to facilitate impedance control, and to have a multi-band structure having a wide band radiation characteristic. It relates to a built-in antenna.

Recently, new information such as a navigation system, a wireless Internet, and Bluetooth utilizing a global position system (GPS) function has emerged, resulting in derivative information products that can generate new profits. As a conventional personal mobile communication service is widely used, a lot of research and development has been concentrated on such a wireless communication system so that the wireless communication system can operate in conjunction with a cellular and personal communication service (PCS) mobile communication system. In fact, the recent trend of legislation of emergency rescue services in preparation for risks such as fire and distress at home and abroad, and newly released mobile terminals to operate GPS function and LBS (Location-Based Service) system in connection with personal mobile communication GPS functions are mandatory in the country, and additional service functions such as transportation, security, and logistics are being actively developed to create new added value. As such, the development of information society demands miniaturization and multifunctionality to increase the mobility of personal terminal for mobile communication, and antenna for SOC (System on Chip) of passive / active parts that make up the entire RF-Front End. Miniaturization is required. Therefore, in recent years, a method of structurally modifying a radiation patch or designing a radiation structure in three dimensions in order to increase the effective current length of a resonant antenna has been attracting attention as a structure for miniaturizing the antenna, and in particular, Planar Inverted F- Like the antenna structure, a miniaturized chip antenna structure has been introduced in various ways by combining a resonance structure which minimizes the reactance in the feeding direction and a simple deformation structure by slit laying.

1 is a view showing a built-in antenna (Korea Patent No. 10-0442053) according to the prior art.

FIG. 1A is a perspective view illustrating the antenna shape and the positions of the conductor patterns and the via holes arranged in the dielectric sheets of each layer. FIG. 1 (b) is a plan view showing the lower layer part of FIG. 1 (a), FIG. 1 (c) is a plan view showing the middle layer part of FIG. 1 (a), and FIG. 1 (d) is the upper layer part of FIG. 1 (a). It is the top view shown.

FIG. 1A illustrates a predetermined line width 30a at upper, middle, and lower portions of the dielectric block 10 to have a meander line-shaped conductor pattern printed on the surface of the dielectric block 10 having the same dielectric constant and volume. The shape of the conductor pattern having the leading gap 30b is formed by using the laminated structure, respectively, for the primary conductor patterns 31 and 32, the secondary conductor patterns 41, 42, 43, and 44, and the third conductor pattern ( 51 shows a conductor pattern separated in shape. In addition, the first conductor pattern and the second conductor pattern are electrically connected to each other through a cylindrical primary via hole 61 in which a circular hole is formed through via punching in the dielectric sheet and a conductor is filled therein. The primary conductor pattern and the tertiary conductor pattern are connected through the secondary via hole 62. FIG. 1 (b) shows a feeder 21 connected to a substrate through soldering and a connecting portion conductor pattern 22 connected in a vertical direction at 90 degrees so as to have an L shape on the side of the feeder, and the lower layer part of FIG. 1 (a). As shown in FIG. 1B, the conductive pattern 51 has a stepped structure having a stepped structure bent 90 degrees to each other in the vertical 52-horizontal 53-vertical 54 directions. . The middle layer conductor patterns are arranged only in the horizontal direction patterns 41, 42, 43 and 44, and the upper layer conductor patterns 31 and 32 are also stepped conductors bent at 90 degrees to each other as shown in FIG. It is formed through the connection of the patterns 33, 34, 35, 36, 37, 38. In addition, the separated conductor pattern in the form of a meander line is vertically stacked in a stepped manner in the order of the secondary conductor pattern-primary conductor pattern-secondary conductor pattern-tertiary conductor pattern in the height direction of the base dielectric block. Structure.

As described above, the built-in antenna having the conventional stacked structure can move the resonance frequency downward with respect to the antenna having the same dielectric volume while maintaining proper coupling between the conductor patterns.

However, as shown in FIG. 1, although the size of the antenna can be reduced by stacking dielectric blocks on which conductor patterns are formed, the first conductor pattern-secondary conductor is formed by stacking thin dielectric sheets on which conductor patterns are formed. Due to the narrowing of the gap between the pattern and the tertiary conductor pattern, interference occurs, and characteristics thereof are difficult to adjust because the characteristics change according to the minute interference. As a result, it is difficult to adjust the impedance of the resonant frequency to be implemented, and thus, fine tuning is difficult, and the bandwidth of the resonant frequency to be narrowed occurs. In addition, because the pattern of the antenna radiation is very complicated and there are too many adjustment factors to obtain the desired characteristics, it is difficult to produce an antenna conforming to the standard.

The present invention has been proposed to solve the above-described problems, and aims to extend the bandwidth of the resonance frequency of an antenna to be implemented by minimizing the interference between the upper and lower radiator patterns. In addition, an object of the present invention is to provide a built-in antenna capable of easily obtaining impedance by controlling impedance without changing the shape or dielectric material of the radiator pattern.

The built-in antenna of the mobile terminal according to the present invention for solving the above problems is an upper dielectric block formed with a first radiator pattern; A lower dielectric block having a second radiator pattern formed thereon; And a multi-layer dielectric block having one or more air gaps punctured in a vertical direction and disposed between the upper dielectric block and the lower dielectric block to electrically connect the first and second radiator patterns.

Preferably, the first radiator pattern is formed on the upper surface of the lower dielectric block.

In addition, the first radiator pattern and the second radiator pattern may be electrically connected to each other through via holes formed in the multilayer dielectric block.

In addition, the lower dielectric block is preferably formed with conductive feed pads and ground pads spaced apart from each other on one side, and the feed pads and ground pads are electrically connected to the first radiator pattern through via holes formed in the multilayer dielectric block.

In addition, the lower, middle and upper dielectric blocks are preferably manufactured using a PCB.

The present invention made as described above will be described in detail with reference to the accompanying drawings. Repeated descriptions, well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention, and detailed description of the configuration will be omitted. Embodiments of the present invention are provided to more completely describe the present invention to those skilled in the art. Accordingly, the shape and size of elements in the drawings may be exaggerated for clarity.

2 is an exploded perspective view of a built-in antenna according to an embodiment of the present invention, Figure 3 is a coupling state diagram of the "A" part of Figure 2, Figure 4 is a coupling state diagram of the "B" part of Figure 2, Figure 5 Is a coupling state diagram of the "C" part of Figure 2, Figure 6 is a coupling state diagram of FIG.

As shown in FIG. 2, the built-in antenna 500 according to an exemplary embodiment of the present invention may include a flat upper dielectric block 100 having a radiator pattern, a lower flat dielectric block 300 having a radiator pattern, The air gaps 295a and 295b are punctured in the vertical direction and include a middle dielectric block 200 stacked between the upper dielectric block 100 and the lower dielectric block 300.

Via holes 110a and 110b are punctured at edge portions positioned in the diagonal direction of the upper dielectric block 100. The inner surfaces of the via holes 110a and 110b are plated or filled with a conductive material. An upper radiator pattern 120 having a meander line shape is formed on an upper surface of the upper dielectric block 100. A first lower radiator pattern 130 and a second lower radiator pattern 140 are formed on a bottom surface of the upper dielectric block 100. One end of the upper radiator pattern 120 is electrically connected to one end of the first lower radiator pattern 130 through the via hole 110b, and the other end of the upper radiator pattern 120 is the second lower radiator through the via hole 110a. It is electrically connected to one end of the pattern 140. The other end of the first lower radiator pattern 130 is formed at a corner portion closest to the corner where the via hole 110b is formed and is connected to the conductive connection pad 220 installed in the multilayer dielectric block 200. The other end of the second lower radiator pattern 140 is formed at a corner portion closest to the corner where the via hole 110a is formed, and is connected to the conductive connection pad 250 installed in the multilayer dielectric block 200.

Here, the upper radiator pattern 120 and the lower radiator patterns 130 and 140 of the upper dielectric block 100 are collectively referred to as a first radiator pattern. The shape of the first radiator pattern may be changed according to a desired resonance frequency. The line width and the line spacing of the first radiator pattern may vary depending on the desired resonance frequency.

Meanwhile, at least one air gap 295a and 295b are formed in the multilayer dielectric block 200, and the air gaps 295a and 295b have a length A and a width B in a direction perpendicular to the multilayer dielectric block 200. And is formed. The multilayer dielectric block 200 according to an embodiment of the present invention has two air gaps 295a and 295b, but the number of air gaps is not limited to two, and the number of air gaps may vary depending on a desired resonance frequency. Can be. In addition, the shape of the air gaps 295a and 295b, the length I and the width M of the through hole may vary depending on the desired resonance frequency.

Conductive connection pads 220 to 290 are provided at corners of the upper and lower surfaces of the multilayer dielectric block 200. The three conductive connection pads 220, 230, and 250 on the top surface are three conductive connection pads 280, 290, and 270 on the bottom surface of the via surface via holes 210a, 210b, and 210c plated or filled with a conductive material. Is electrically connected to the The conductive connection pads 240 and 260 are respectively provided on the upper and lower surfaces of the corner portions where the via holes are not formed.

On the upper surface of the lower dielectric block 300, a second radiator pattern 390 having a meander line shape is formed. The second radiator pattern 390 is formed to be spaced apart from the NO-GND region on the main board PCB of the terminal by at least the height of the lower dielectric block 300. Therefore, since the space allocated on the main board is reduced to form a no-ground area, a built-in antenna suitable for slimming and miniaturization of a mobile terminal can be provided.

One end of the second radiator pattern 390 is connected to the conductive connection pad 270 provided in the multilayer dielectric block 200.

A ground pad 370 and a power feeding pad 380 are installed at one end edge portion of the bottom surface of the lower dielectric block 300. The ground pad 370 is electrically connected to the conductive connection pad 320 through a via hole 310a, the inside of which is plated or filled with a conductive material, and the feed pad 380 has a via hole plated or filled with a conductive material inside the ground pad 370. It is electrically connected to the conductive connection pad 330 through 310b. Conductive connection pads 340 and 350 are provided on the upper and lower surfaces of one edge of the lower dielectric block 300 in which no via holes are formed, and the conductive pads are also adjacent to the corners in which the conductive connection pads 350 are installed. 360 is installed.

The upper, middle, and lower dielectric blocks 100, 200, and 300 are preferably made of PCB. The PCB is not only easy to form the air gap, but also easy to obtain the desired characteristics in a short time by adjusting the length (I) and width (M) of the air gap.

In the upper, middle, and lower dielectric blocks 100, 200, and 300, the height of the lower dielectric block 300 is the minimum of three dielectric blocks, and the height of the multilayer dielectric block 200 is the maximum of the three dielectric blocks. . By making the height of the multilayer dielectric block 200 relatively higher than other dielectric blocks, a sufficient air gap is ensured to minimize interference between the first radiator pattern 120 and the second radiator pattern. In addition, the height of the lower dielectric block 300 is minimized to reduce the overall size of the antenna.

As shown in FIG. 6, the multilayer dielectric block 200 is stacked on the upper surface of the lower dielectric block 300, and the upper dielectric block 100 is stacked on the upper surface of the multilayer dielectric block 200. Accordingly, the second lower radiator pattern 140 formed on the upper dielectric block 100 and the second radiator pattern 390 formed on the upper surface of the lower dielectric block 300 have via holes 210c plated or filled with a conductive material therein. The first radiator patterns 120 to 140 and the second radiator pattern 390 are electrically connected to each other to form one radiator line. In addition, the feed pad 380 is connected to one end of the first lower radiator pattern 130 through the via holes 310b and 210b, and the ground pad 370 is connected to the first lower radiator pattern through the via holes 310a and 210a. It is connected to the other end of the 140.

Conventionally, as the terminal environment changes, the shape or dielectric material of the radiator pattern is changed. However, as shown in FIG. 6, the built-in antenna of the multi-layered structure of the present invention does not change the shape or dielectric material of the radiator pattern. If the number of air gaps 295a and 295b formed in the dielectric block 200 is adjusted or the length I and width M of the air gaps are adjusted, desired characteristics can be obtained in a short time. That is, since the air gap between the upper dielectric block 100 and the lower dielectric block 300 can be adjusted simply by changing the structure, the precise process according to the shape of the radiator pattern or the dielectric material is reduced, and thus the cost Can be reduced. In addition, by forming an air gap between the upper dielectric block 100 and the lower dielectric block to minimize the interference between the first radiation pattern (120 to 240) and the second radiation pattern 390 by a wider bandwidth at a desired resonance frequency It is possible to provide a built-in antenna having a. In addition, by stacking the upper, middle, and lower dielectric blocks 100, 200, and 300 having the radiator pattern formed thereon, the resonance frequency can be shifted downward with respect to the antenna having the same dielectric volume while maintaining mutual coupling between the conductor patterns. Will be. That is, the size of the antenna can be effectively reduced without significantly affecting the characteristics of the antenna.

As mentioned above, although one preferred embodiment of the present invention has been illustrated and described, the present invention is not limited to the specific embodiments described above, and the present invention belongs to the present invention without departing from the gist of the present invention as claimed in the claims. Various modifications can be made by those skilled in the art, and these modifications should not be understood individually from the technical idea or the prospect of the present invention.

As described above, the built-in antenna according to the present invention is easy to adjust the impedance to obtain a built-in antenna that implements the desired characteristics in a short time, the precise process according to the change of the shape of the conventional radiator pattern or dielectric material, etc. There is no need to save money. In addition, by stacking dielectric blocks formed with a radiator pattern, the resonance frequency is shifted downward with respect to an antenna having the same dielectric volume, and an air gap with a minimum dielectric constant is formed between dielectric blocks formed with the radiator pattern, thereby forming an upper radiator pattern and a lower layer. By minimizing the interference between the radiator patterns, it is possible to obtain a built-in antenna having a wide bandwidth for the desired resonance frequency.

Claims (5)

An upper dielectric block on which the first radiator pattern is formed; A lower dielectric block having a second radiator pattern formed thereon; And One or more air gaps are punctured in a vertical direction, and are disposed between the upper dielectric block and the lower dielectric block, the multilayer dielectric block electrically connecting the first and second radiator patterns. Built-in antenna characterized by. The method according to claim 1, And a first radiator pattern formed on an upper surface of the lower dielectric block. The method according to claim 1, And the first radiator pattern and the second radiator pattern are electrically connected to each other through via holes formed in the multilayer dielectric block. The method according to claim 1, The lower dielectric block is formed with conductive feed pads and ground pads spaced apart from each other on one side, and the feed pads and the ground pads are electrically connected to the first radiator pattern through via holes formed in the multilayer dielectric block. Built-in antenna, characterized in that. The method according to claim 1, The lower layer, the middle layer, and the upper layer dielectric block are built-in antenna, characterized in that manufactured using a PCB.

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