KR100368939B1 - An internal antenna having high efficiency of radiation and characteristics of wideband and a method of mounting on PCB thereof - Google Patents

Abstract

The present invention relates to a built-in antenna mounted on a printed circuit board of various mobile communication terminals, to a built-in antenna having a high radiation efficiency and broadband characteristics and a mounting method thereof.

Conventional built-in antennas have a fundamental problem such as poor radiation efficiency and narrow bandwidth due to miniaturization. SUMMARY OF THE INVENTION The present invention has been made to solve this problem, and a ground conductor plate connected to a ground plane; and a first conductor plate parallel to the ground conductor plate and serving as a first radiator; and for feeding the first conductor plate. A conductive feed probe pin; a second conductor plate parallel to the first conductor plate and electromagnetically coupled to the first conductor plate and becoming a second radiator; and the second conductor plate and the first conductor plate. A connecting conductor plate connecting the plates; And a first vertical conductor plate extending from the second conductor plate to the ground conductor plate and connected to the ground conductor plate.

The built-in antenna having high radiation efficiency and broadband characteristics according to the present invention has a radiation efficiency close to 100% because there is no dielectric loss due to the support because the radiator is composed of only a metal conductor, and the spacing between two patches stacked up and down is appropriately adjusted. By inducing a coupling effect with the vertical patch connected thereto, it has a broadband characteristic of 420MHz or more, which is about four times the general operating bandwidth of the existing internal antenna.

Description

An internal antenna having high efficiency of radiation and characteristics of wideband and a method of mounting on PCB

The present invention relates to a built-in antenna mounted on a printed circuit board of various mobile communication terminals, and more particularly, there is almost no loss due to a dielectric, and thus the gap between two patches stacked up and down with high radiation efficiency. The present invention relates to a built-in antenna having a high radiation efficiency and a wideband characteristic and a method of mounting the same by appropriately adjusting and inducing a coupling effect with a vertical patch connected thereto.

Antennas currently installed in various mobile communication terminals include a monopole antenna having a length of λ / 4 ( λ is a wavelength of a used frequency) and an electrically corresponding length ( λ / 4). Helical (helical) antenna having a retractable antenna (retractable antenna) is a mainstream is a combination of two types of antennas. By the way, this type of antenna has a structure that is mounted on the outside of the main body of the terminal fundamentally has become the biggest obstacle in the task of miniaturizing the terminal compared to other terminal components. Therefore, in recent years, the miniaturization of the antennas as described above, and also in the method of mounting the antenna, the research on the built-in antenna that can directly mount the antenna on the internal printed circuit board of the terminal by moving away from the existing external type is actively conducted. It is becoming a trend.

The technologies of such built-in antennas that have been advanced until recently are largely microstrip patch antenna technology using printed circuit technology, ceramic chip antenna technology using high dielectric ceramic material, and inverse F which has been tried recently. (Inverted F) antenna technology, etc. However, this type of built-in antenna faces a fundamental design problem in that bandwidth decreases as the antenna size decreases. In particular, in the case of inverted-F antennas, a technique of using probe feeding on a radiator has a very narrow bandwidth, which makes it difficult to use them in a wide bandwidth service. Due to the use of materials, there is a disadvantage in that the loss of the antenna is a problem. In addition, in the case of the microstrip patch antenna technology using a printed circuit board (PCB), it is possible to facilitate frequency tuning and bandwidth expansion using various slot technologies and stacking techniques. However, there is a disadvantage that the antenna volume accordingly increases.

Therefore, if broadband communication services such as next-generation mobile communication (IMT-2000) service to be used in the future are provided in addition to the communication service that is currently commercialized, to cover the multi-band with a single antenna in order to effectively satisfy these broadband communication services, There is a need for antenna technology with radiation efficiency, which requires the development of a new concept of built-in antenna technology that goes beyond the current built-in antenna design technology.

The present invention has been made to solve the above problems, in the case of a built-in antenna, such as a conventional ceramic antenna or a microstrip patch antenna, a loss caused by using a dielectric having a high dielectric constant to reduce the size of the antenna The present invention provides a built-in antenna having a very high radiation efficiency by using a radiator composed of only a metal conductor plate without using the same.

Another technical problem of the present invention is to generate an electromagnetic coupling between two patches by stacking the radiators in a vertically parallel double patch structure and adjusting their spacing, and further comprising a vertical radiator coupled thereto. It is to provide a built-in antenna to have a wideband characteristic.

1A is a perspective view from above of an embodiment of a built-in antenna having high radiation efficiency and broadband characteristics according to the present invention;

FIG. 1B is an external perspective view of the embodiment of FIG. 1A seen from below; FIG.

FIG. 2 is a mounting view illustrating a state in which the embodiment of FIG. 1A is mounted on a printed circuit board of a terminal. FIG.

3 is a standing wave ratio characteristic showing a frequency band of the embodiment of FIG.

4A is a radiation pattern diagram at an electric field plane of the embodiment of FIG. 1A.

4B is a radiation pattern diagram at the magnetic field plane of the embodiment of FIG. 1A.

5A is a perspective view from above of another embodiment of a built-in antenna having high radiation efficiency and broadband characteristics according to the present invention;

FIG. 5B is an external perspective view of the embodiment of FIG. 5A seen from below; FIG.

FIG. 6 is a mounting view illustrating a state in which the embodiment of FIG. 5A is mounted on a printed circuit board of a terminal. FIG.

FIG. 7 is a standing wave ratio characteristic showing an operating frequency band of the FIG. 5A embodiment; FIG.

8A is a perspective view from above of another embodiment of a built-in antenna having high radiation efficiency and broadband characteristics according to the present invention;

FIG. 8B is an external perspective view of the embodiment of FIG. 8A seen from below; FIG.

FIG. 9 is a mounting view illustrating a state in which the embodiment of FIG. 8A is mounted on a printed circuit board of a terminal. FIG.

FIG. 10 is a standing wave ratio characteristic showing an operating frequency band of the FIG. 8A embodiment; FIG.

※ Explanation of codes for main parts of drawing

101. Probe pin 102. First conductor plate

103. Second conductor plate 104. First vertical conductor plate

105. Grounding conductor plate 106. First slot

107. Second vertical conductor plate 108. Circular slot

109. The second slot 110. The third slot

111. Fourth slot 112. Connecting conductor plate

501. Fifth slot 502. Sixth slot

503. Third vertical conductor plate 504. Seventh slot

505. Eighth Slot 506. Ninth Slot

801. The eleventh slot 802. The twelfth slot

803. 13th slot 804. 14th slot

805. Slot 15 806. Feed Conductor Plate

807. Grounding conductor plate 808. 17th slot

809. Sixteenth Slot 810. Eighteenth Slot

811.Seventh Slot 812.Seventh Slot

In order to solve the above technical problem, the built-in antenna having a high radiation efficiency and broadband characteristics according to the present invention, a ground conductor plate electrically connected to the terminal ground plane; and parallel to the ground conductor plate at a predetermined interval And a rectangular first conductor plate having a feed point at a predetermined position and serving as a first radiator; and a conductive feed probe pin connecting the feed point and the terminal internal circuit to feed the first conductor plate; and the first A second conductor plate which is formed in parallel with a predetermined interval on the conductor plate and is a second radiator having a square shape electromagnetically coupled to the first conductor plate; and one side surface of the second conductor plate and the first conductor plate. A connecting conductor extending vertically from one side of the first conductor plate and electrically connected to one side of the second conductor plate so as to electrically connect one side of the first conductor plate; .; And a first vertical conductor plate extending vertically downward from the side surface of the second conductor plate to electrically connect the side surface of the second conductor plate and the ground conductor plate, and becoming a vertical radiator.

Hereinafter, exemplary embodiments of a built-in antenna having high radiation efficiency and broadband characteristics according to the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same or corresponding members will be denoted by the same reference numerals and detailed description thereof will be omitted.

Figure 1a and Figure 1b is an external view showing an embodiment of a built-in antenna having a high radiation efficiency and broadband characteristics according to the present invention, Figure 1a is an external perspective view seen from above, Figure 1b is an external perspective view seen from below. The signal fed to the first conductor plate 102 through the feed probe pin 101 connected to the internal circuit of the terminal is transmitted to the second conductor plate 103 through the connection conductor plate 112. The signal input to one side of the second conductor plate is transmitted to the ground conductor plate 105 through the first vertical conductor plate 104.

The first conductor plate 102 has a " U " shape by a first slot 106 formed long in the center of the plate at one side thereof, and a feed point is formed at one end thereof, and the second end at the other end thereof. The connection conductor plate 112 is formed to be extended to electrically connect the conductor plate 103. In addition, on the other side, a second vertical conductor plate 107, which becomes a vertical radiator, is extended upward. The first conductor plate 102 has a feed point at one end thereof, and thus has a large influence on the input impedance characteristics of the antenna. The first slot 106 can adjust the overall transmission length of the first conductor plate 102 by adjusting its length, thereby acting as an important parameter in determining the operating frequency of the antenna. In addition, the second vertical conductor plate 107, which extends from the other side of the first conductor plate 102 and is formed vertically upward, is spaced apart from the second conductor plate at a predetermined interval and functions as a vertical radiator. . Also, by adjusting the height, the height is used to expand the bandwidth according to the coupling effect between the first conductor plate and the second conductor plate.

The second conductor plate 103 serving as the main radiation body has a rectangular shape parallel to the first conductor plate 102, and a circular slot 108 is formed at one side thereof, and the plate is formed from one side of the circular slot. The second slot 109 is formed in the center portion in the longitudinal direction. In addition, a fourth slot having a quadrangle between the third slot 110 and the third slot and the circular slot 108 having an inverted “a” shape at a predetermined interval from the second slot 109. 111 is formed.

The circular slot 108 allows the signal input from the connecting conductor plate 112 to be smoothly branched and transmitted to the left (clockwise) and the right (counterclockwise) of the circle, resulting in the multi-path. It is responsible for inducing bandwidth expansion. Although slots of other shapes than circular, such as slots of rectangular or triangular shape, can perform this function, angled slots may cause perturbation that interferes with branching of the signal current. Therefore, in the present embodiment, a circular slot is selected for smooth branching. However, the present invention is not limited thereto.

The second slot 109 and the third slot 110 having an inverted “a” shape form an independent “U” shaped transmission path to the left side (clockwise) of the circular slot 108. By varying each length and position, the overall path length to the left of the circular slot 108 can be adjusted to be used to tune the operating frequency of the antenna with the first slot 106.

Unlike the circular slot 108, the fourth slot 111 of the quadrangle positioned between the third slot 110 and the circular slot 108 causes perturbation between the branch of the signal current and the individual signal current. It can be used to expand the bandwidth due to parasitic radiation.

In addition, it is preferable that the first conductor plate 102 and the second conductor plate 103 are very close to each other so as to be electromagnetically coupled, and the electromagnetic coupling between the adjacent double patches is a gain of the antenna. To improve the performance and expand the operating bandwidth.

The first vertical conductor plate 104, which is connected to the ground plane of the terminal via the ground conductor plate 105, is another vertical radiator, the height of which is one of the main variables that can expand the bandwidth of the entire antenna. .

FIG. 2 is a mounting view illustrating a state in which the embodiment of FIG. 1A is mounted on a printed circuit board of a terminal. As shown in the drawing, the antenna is exposed to the outside by a predetermined offset length from the upper left side of the substrate having the ground plane engraved thereon. This is to eliminate the deterioration of the radiation characteristic caused by the ground plane of the substrate too close to the antenna. It is also possible to remove the ground plane of the substrate by the offset length. That is, by matching the edge of the antenna to the upper left corner of the substrate where the ground plane is engraved and removing the ground plane by the offset length, the above effects can be obtained.

3 is a standing wave ratio characteristic showing a frequency band of the embodiment of FIG. The horizontal axis represents the frequency range (GHz), and the vertical axis represents the return loss (dB). As can be seen from the figure, the built-in antenna having high radiation efficiency and broadband characteristics according to the present invention has a broadband characteristic of about 420 MHz (1.58 to 2 GHz) based on -10 dB (corresponding to standing wave ratio 2: 1). The size of the antenna used for the measurement was 30 × 12 × 4 [mm] in width, length, and height, respectively, and the spacing between the first conductor plate 102 and the second conductor plate 103 was 1.5 [mm]. .

4A and 4B are diagrams of a radiation pattern (ie, a vertical plane pattern) and a radiation pattern (ie, a horizontal plane pattern) at an magnetic field (H-plane), respectively, of the embodiment of FIG. 1A. In FIG. 4A, it can be seen that the gain maximum value of 2.1 [dBi] is obtained at 155 degrees oriented about 25 degrees downward from the vertical plane of the antenna. As the antenna is mounted on the top of the printed circuit board, the beam pattern is directed toward the ground plane. This is due to a rather slanting characteristic. 4b shows that it has a maximum value of 1.3 dBi at 190 degrees. For reference, the size of the antenna used for the measurement was the same as the antenna used in FIG.

5a and 5b is an external view showing another embodiment of the built-in antenna having a high radiation efficiency and broadband characteristics according to the present invention. 5A is an external perspective view seen from above, and FIG. 5B is an external perspective view seen from below. The configuration difference with the embodiment of FIG. 1A is that the length of the overall antenna is longer, and the slot formed in the first conductor plate 102 is divided into two (501, 502), and formed in the second conductor plate 103. The slots 504, 505, and 506 are all in the longitudinal direction of the antenna, and thus have different transmission paths, and a vertical radiator 503 is added to one side of the second conductor plate 103, and a ground conductor plate for grounding ( 105) is located at the bottom center of the antenna. The fifth slot 501 and the sixth slot 502 formed separately in the first conductor plate 102 induce a bandwidth expansion due to multipath by forming another transmission path passing between the two slots.

The second conductor plate 103 having a rectangular plate shape and designed to resonate in a high frequency band as shown in FIG. 7 has a first vertical conductor extending on one side in the longitudinal direction for bandwidth expansion through a vertical radiator. It has a plate 104 and a third vertical conductor plate 503 formed extending on one side in the longitudinal direction.

Unlike the second slot 109 of FIG. 1A, the seventh slot 504 formed in the longitudinal direction shortens and blocks the path to the left side (clockwise) of the circular slot 108 to the right side of the circular slot 108. Allow the signal to rotate and flow. This generates a phase difference between a signal flowing directly to the right from a connecting conductor plate (not shown) and a signal due to the rotation, thereby causing parasitic radiation due to interference between signals having a phase difference, thereby extending the bandwidth. .

In order to form a zigzag-shaped transmission path, a comb-shaped eighth slot 505 formed in the longitudinal direction of the antenna and a plurality of ninth slots 506 periodically formed to face each other are relatively relatively small in a small antenna. By allowing the long transmission path to be generated, the resonance occurs in the low frequency band as shown in FIG. In addition, the zigzag path used in the present embodiment has a wider track width and a narrower distance than the general zigzag-type track, thereby facilitating bandwidth expansion through parasitic coupling.

FIG. 6 is a mounting view illustrating a state in which the embodiment of FIG. 5A is mounted on a printed circuit board. FIG. Unlike the method of FIG. 2, the mounting method is performed by removing the ground plane by an offset.

7 is a standing wave ratio characteristic representing an operating frequency band of the embodiment of FIG. 5A. The horizontal axis represents the frequency range (MHz) and the vertical axis represents the standing wave ratio. Based on the case where the standing wave ratio is 2.5: 1, the bandwidth is about 813 MHz due to the broadband characteristics of about 460 MHz (1.74 to 2.2 GHz) and the zigzag-shaped path formed on the second conductor plate 103. It can be seen that a band is formed.

8A and 8B are external views illustrating still another embodiment of an internal antenna having high radiation efficiency and broadband characteristics according to the present invention. 8A is an external perspective view seen from above, and FIG. 8B is an external perspective view seen from below. The configuration difference from the embodiment of Figure 5a is provided with a feed conductor plate 806 for power feeding in the lower portion of the antenna, a plurality of slots facing the left side of the second conductor plate 103 and the ground conductor plate 105 804, 805, 810, and 811 are formed, and the first vertical conductor plate 104 also has slots 808 and 809 of a predetermined shape to form another transmission path, and the second conductor plate 103 A ground connection conductor plate 807 for connecting the ground conductor plate 105 is included, and only one slot 812 is formed in the first conductor plate 102 and on the right side of the second conductor plate 103. One side of the formed zigzag-shaped path and the first vertical conductor plate 104 are directly connected to each other.

The feed conductor plate 806 is configured to feed a signal to the second conductor plate 103, the first conductor plate 102, and the ground conductor plate 105 through the first vertical conductor plate 104. It is directly connected to the internal circuit in the same way as soldering. Two types of transmission paths are formed in the second conductor plate 103 by slots 108, 801, 802, 803, 804, and 805 of various types, and the first vertical conductor plate is directly connected to these paths. The power feeding method through 104 allows the resonant characteristic of two frequency bands (dual band) as shown in FIG.

A zigzag path formed on the left side of the second conductor plate receiving a signal through the right side of the second conductor plate 103 and a zigzag path formed on the ground conductor plate 105 connected thereto by the ground connection conductor plate 807. As shown in FIG. 10, the total length of the actual signal current is greatly increased, thereby improving the resonance characteristics in the low frequency band.

In addition, the left zigzag path of the second conductor plate having a relatively narrow width by the wide slot formed on the left side of the second conductor plate 103 is reinforced with an inductance component, and thus is zigzag formed on the right side of the second conductor plate. Parallel connection with the path of the type has the effect of facilitating tuning and bandwidth expansion of the operating frequency.

One side of the first vertical conductor plate 104 is provided with a vertical radiator formed by extending and bending part of the zigzag transmission path of the second conductor plate 103, which is also used for bandwidth extension.

FIG. 9 is a mounting view illustrating a state in which the embodiment of FIG. 8A is mounted on a printed circuit board, and the ground plane is removed by an offset.

FIG. 10 is a standing wave ratio characteristic representing an operating frequency band of the embodiment of FIG. 8A. The horizontal axis represents the frequency range (MHz) and the vertical axis represents the standing wave ratio. Unlike the embodiment of FIG. 5A, the bandwidth of the low frequency band is considerably increased by the path formed on the left side of the second conductor plate 103 and the ground conductor plate 105.

As described above, the built-in antenna having high radiation efficiency and broadband characteristics according to the present invention can be directly mounted on the printed circuit board of the terminal, thereby enabling mass production and miniaturization of the terminal according to the automation process, and thus gain In order to effectively solve the degradation problem, the antenna is composed of only a metal conductor so that a lossless radiator support is not required, and thus the radiation efficiency is close to 100%.

In addition, as shown in Figure 4 by using the adjacent double patch and vertical patch structure has the effect of having the characteristics of the broadband, the existing built-in type in the antenna size of about 30 × 12 × 4 [mm] which is an embodiment of the present invention It has a wide bandwidth characteristic of 420MHz or more, which is about four times the general operating bandwidth of the antenna, and the center frequency can be easily adjusted by forming various types of slots as in the embodiment of FIG. 5A or 8A. It also has the effect of providing a band antenna.

Claims (9)

In the built-in antenna mounted on a printed circuit board of various mobile communication terminal, A ground conductor plate electrically connected to a ground plane of the printed circuit board; A rectangular first conductor plate parallel to the ground conductor plate at predetermined intervals, having a feed point at a predetermined position, and having one or more slots to form a first copy; A conductive feed probe pin connecting the feed point and the internal circuit of the terminal to feed the first conductor plate; A second conductor plate having a rectangular shape parallel to the first conductor plate at predetermined intervals, the second conductor plate having one or more slots to become a second radiator; A connecting conductor extending vertically upward from one side of the first conductor plate and electrically connected to one side of the second conductor plate to electrically connect one side of the second conductor plate and one side of the first conductor plate. plate; And A height extending vertically downward from the side surface of the second conductor plate to electrically connect the side surface of the second conductor plate and the ground conductor plate, the first vertical conductor plate including a first vertical radiator; Built-in antenna with radiation efficiency and broadband characteristics. delete delete The method of claim 1, And a second vertical conductor plate extending vertically upward from one side of the first conductor plate, the second vertical conductor plate being a second vertical radiator. The method of claim 1, Slots provided in the second conductor plate, A circular slot 108 provided at one side of the second conductor plate to branch signals; A second slot 109 elongated from one side of the circular slot to the center of the second conductor plate; A third slot 110 formed at an inverse “a” at a predetermined distance from the second slot; And The fourth slot 111 is provided between the one end of the third slot and the circular slot to generate a current perturbation, Slots provided in the first conductor plate, A first slot 106 is formed long from one side of the first conductor plate to the other side, Built-in antenna having a high radiation efficiency and broadband characteristics, characterized in that it further comprises a second vertical conductor plate 107 is formed to extend vertically upward from one side of the first conductor plate to become a second vertical radiator. delete delete The method of claim 1, Slots provided in the first conductor plate, A fifth slot 502 formed to extend from one side to the other side of the first conductor plate; A sixth slot 501 positioned in line with the fifth slot and provided at predetermined intervals; Slots provided in the second conductor plate, A circular slot 108 provided at one side of the second conductor plate to branch signals; A seventh slot 504 extending in the longitudinal direction of the second conductor plate from one side of the circular slot; An eighth slot 505 in the shape of a comb that is formed in a longitudinal direction on one side of the second conductor plate; And A plurality of ninth slots 506 formed on the other side of the second conductor plate so as to be opposed to the eighth slots; A second vertical conductor plate 107 extending vertically from one side of the first conductor plate and becoming a second vertical radiator; Built-in antenna having a high radiation efficiency and broadband characteristics, characterized in that it further comprises a third vertical conductor plate 503 is formed extending vertically downward from one side of the second conductor plate to be a third vertical radiator. In the built-in antenna mounted on a printed circuit board of various mobile communication terminal, A ground conductor plate 105 electrically connected to a ground plane of the printed circuit board; A first rectangular parallelepiped plate (102) parallel to the ground conductor plate at a predetermined interval and becoming a first radiator; A rectangular second conductor plate 103 parallel to the first conductor plate at a predetermined interval and becoming a second radiator; A connecting conductor extending vertically upward from one side of the first conductor plate and electrically connected to one side of the second conductor plate to electrically connect one side of the second conductor plate and one side of the first conductor plate. plate; A first vertical conductor plate 104 extending vertically downward from a side surface of the second conductor plate to electrically connect the side surface of the second conductor plate to the ground conductor plate, and becoming a first vertical radiator; A feed conductor plate 806 formed to be parallel to the ground conductor plate at a predetermined interval, one end of which is connected to the first vertical conductor plate and the other end of which is connected to the internal circuit of the terminal; A tenth slot 812 extending from one side of the first conductor plate to the other side; A circular slot provided on one side of the second conductor plate; An eleventh slot 801 formed to extend in the longitudinal direction of the second conductor plate from one side of the circular slot; A plurality of twelfth slots 802 formed on one side side by side at a predetermined interval in the longitudinal direction of the second conductor plate; A plurality of thirteenth slots 803 formed on the other side of the second conductor plate so as to face the twelfth slot; A plurality of fourteenth slots 804 formed on one side of the second conductor plate at a side by a predetermined interval in a longitudinal direction, the width of the second conductor plate being greater than the width of the twelfth slot; A plurality of fifteenth slots 805 formed between the fourteenth slots and having a length equal to the length of the second conductor plate; A second vertical conductor plate 107 extending vertically upward from one side of the first conductor plate and becoming a second vertical radiator; A sixteenth slot 809 extending from the fourteenth slot and formed in the first vertical conductor plate and having a comb shape; A plurality of seventeenth slots 808 extending from the fifteenth slot and formed in the first vertical conductor plate; A ground connection conductor plate 807 extending vertically downward from one side of the second conductor plate and connected to the ground conductor plate; A plurality of eighteenth slots 810 formed on one side of the ground conductor plate at a side by side at a predetermined interval in the longitudinal direction; And Built-in antenna having a high radiation efficiency and broadband characteristics including a plurality of nineteenth slot (811) formed on the other side of the ground conductor plate opposite to the eighteenth slot.