WO2005020371A1

WO2005020371A1 - Antenna structure and communication unit employing it

Info

Publication number: WO2005020371A1
Application number: PCT/JP2004/011995
Authority: WO
Inventors: Takashi Ishihara; Kengo Onaka; Jin Sato; Shoji Nagumo; Kazunari Kawahata
Original assignee: Murata Manufacturing Co., Ltd.
Priority date: 2003-08-22
Filing date: 2004-08-20
Publication date: 2005-03-03
Also published as: EP1657785A4; JP4013978B2; CN1836351B; CN1836351A; EP1657785A1; JPWO2005020371A1

Abstract

An antenna structure (1) comprising a substrate (2) on which a ground part is formed, a radiation electrode (3) arranged on one end side of the substrate (2), and a ground extension part (4) interconnecting the radiation electrode (3) and the ground part of the substrate (2). The ground extension part (4) connected with the opposite side edge parts of the radiation electrode (3) on the ground end (S) side is extended from the connecting part of the radiation electrode (3) connected with the ground end (S) side to the open end (K) side of the radiation electrode (3) and the fore ends of the ground extension part (4) is connected with the ground part of the substrate (2).

Description

Specification

Antenna structure and communication device using the same

Technical field

The present invention relates to an antenna structure provided in a wireless communication device such as a mobile phone and a communication device using the same.

Background art

[0002] Fig. 18a shows an example of an antenna structure in a schematic perspective view (for example, see Patent Document 1). In the antenna structure 30, the radiation electrodes 31 and 32 are connected via the connecting portion 33, and the radiation conductors 31 and 32 are provided with a ground conductor 34 which is disposed to face the radiation electrodes 31 and 32 with an interval. The radiation electrodes 31 and 32 are both connected to the ground conductor 34 via the short-circuit conductor 35 connected to the connection portion 33. In addition, a power supply conductor 36 is connected to the connection portion 33, and the radiation electrodes 31 and 32 are connected to the radio frequency circuit 37 for wireless communication of a communication device, for example, via the power supply conductor 36.

[0003] Patent Document 1: JP 2003-101336 A

Disclosure of the invention

Problems to be solved by the invention

[0004] The antenna structure 30 can be manufactured, for example, by bending a conductor plate having a shape as shown in Fig. 18b punched from a sheet metal at positions A, B and C shown in Fig. 18b. .

However, when the antenna structure 30 is viewed from the side shown in FIG. 18a, the antenna structure 30 has a U-shape in which the radiation electrodes 31, 32 and the ground conductor 34 are arranged to face each other. ing. It is very troublesome to form the antenna structure 30 having such a U-shape by bending a single conductor plate, and there is a problem that a large area of the conductor plate is required.

An object of the present invention is to provide an antenna structure that is easy and inexpensive to manufacture and a communication device using the same.

Means for solving the problem [0007] The antenna structure of the present invention is an antenna structure having a substrate on which a ground portion is formed and a radiation electrode made of a plate material for performing an antenna operation, and one end of the radiation electrode is formed as a ground end. The opposite end of the radiating electrode from the ground end is arranged along the substrate surface with an interval above the substrate, and at least the side edges of the radiating electrode on the ground end side are respectively radiated. A ground extension extending from the ground end of the electrode to the opposite end of the ground is connected, and the extension end of the ground extension is connected to the ground of the substrate. It is characterized by doing. Further, a communication device according to the present invention is provided with the antenna structure according to the present invention.

The invention's effect

[0008] The antenna structure of the present invention has a radiation electrode, and a ground extension connected to at least both side edges on the ground end side of the radiation electrode, and the ground extension includes: The structure is such that it extends from the connection with the radiation electrode toward the opposite end of the radiation electrode from the ground end. With this configuration, and when the radiation electrode and the ground extension are viewed from above the radiation electrode surface, the radiation electrode and the ground extension have an arrangement such that they do not overlap with each other. As shown, the antenna structure can be easily manufactured. In other words, after punching out the formation part of the radiation electrode and the formation part of the ground extension connected to it from the conductor plate, the radiation electrode is bent and raised in the upright direction with the ground end side of the radiation electrode as the base point. By bending the radiating electrode in the horizontal direction at a position in the middle of the radiating electrode, the radiating electrode and the extension for grounding in the present invention can be manufactured continuously and easily. Therefore, according to the present invention, the manufacturing process of the antenna structure can be simplified, and the antenna structure can be easily mass-produced. Thereby, the manufacturing cost of the antenna structure can be kept low.

[0009] By the way, for example, the ground extension is made to have the same width as the width between the side end faces on both sides of the radiation electrode, and the ground extension is formed from the ground end side of the radiation electrode to the radiation electrode surface with an interval from the radiation electrode. It is conceivable to adopt a configuration in which the radiation electrode is extended to the opposite end side of the grounding end of the radiating electrode so as to face the ground electrode, and the extending end is connected to the grounding portion of the substrate. In this case, for example, using a press machine that moves the metal fitting (die) vertically with respect to the conductive plate (sheet metal) to remove the conductive plate, The plate is processed continuously, and It is difficult to manufacture the radiating electrode integrally with the grounding extension part, which has the same width as the radiating electrode and is opposed to the radiating electrode with an interval, as described above. Hang on.

[0010] On the other hand, in the present invention, as described above, the radiation plate and the ground extension can be integrally formed by continuously processing the conductor plate, and thus the antenna structure as described above is provided. The effect of simplifying the manufacturing process of the structure, the effect of achieving mass production of the antenna structure, and the effect of reducing the manufacturing cost of the antenna structure can be obtained. Further, according to the present invention, the following effects can be obtained. That is, current flows between the ground portion of the substrate and the ground end of the radiation electrode in the ground extension portion due to the antenna operation of the radiation electrode. Even if the ground extension has the same width as the radiation electrode and is a wide ground extension facing the radiation electrode, the current caused by the antenna operation of the radiation electrode will remain on the side edge of the ground extension. Concentrate electricity. In consideration of this, even if the ground extension has only the side edge where the current is concentrated, it is possible to prevent the electrical characteristics of the antenna structure from having a large adverse effect. For this reason, the grounding extension is arranged, for example, at a position outside the side end face of the radiation electrode, and the width of only the side edge where the current is concentrated as described above is narrow, so that the antenna structure can be formed. It is possible to reduce the area of the conductor plate required for manufacturing the radiation electrode and the ground extension while preventing a significant adverse effect on the electrical characteristics. Thereby, the material cost of the antenna structure can be reduced, and the cost of the antenna structure can be reduced.

[0011] The size of the space surrounded by the radiation electrode, the ground extension, and the ground portion is sometimes referred to as the electric volume of the radiation electrode. The electric volume of the radiation electrode is referred to as the radiation electrode. Related to the frequency bandwidth of wireless communication. The connection between the grounding end of the radiation electrode and the ground extension is located at a position outside the substrate on one side and below the substrate, and the other end of the radiation electrode opposite to the grounding end is on the substrate. With the configuration arranged on the upper side, the ground end of the radiation electrode protrudes below the substrate, so if the ground end of the radiation electrode does not protrude below the substrate, In comparison, the electrical volume of the radiation electrode can be increased by the amount protruding downward. This makes it possible to widen the frequency band. [0012] Further, an additional ground extension is provided on the ground end side between both end surfaces of the radiation electrode. The connection can be made more secure.

[0013] Furthermore, by dividing the radiation electrode into a plurality of branch radiation electrode portions or by arranging a plurality of radiation electrodes in parallel, for example, each of the branch radiation electrode portions and each of the radiation electrodes have a resonance frequency shifted from each other. By configuring so as to resonate, it is possible to widen the frequency band for wireless communication, or to enable wireless communication in a plurality of mutually different frequency bands.

[0014] Further, at least one of the plurality of branch radiation electrode portions is formed as a feed type branch radiation electrode portion, and the other branch radiation electrode portions are formed as non-feed type branch radiation electrode portions. With this configuration, the frequency band for wireless communication can be widened by the multiple resonance of the feed-type branch radiation electrode and the non-feed type branch radiation electrode.

[0015] Furthermore, by providing a rib for reinforcing the bending strength at the side edge of the ground extension, it is possible to prevent the ground extension from bending or twisting. Furthermore, by forming a power supply electrode by cutting and raising a part of the radiation electrode, the connection between the radiation electrode and the power supply electrode can be eliminated, thereby avoiding the problem of poor connection between the radiation electrode and the power supply electrode. And the reliability of the antenna structure can be improved.

[0016] Furthermore, by providing a dielectric on at least a part of the radiation electrode, the electrical length (electric length) of the radiation electrode can be increased by the wavelength shortening effect of the dielectric. Can be achieved.

[0017] By configuring the communication device provided with the antenna structure of the present invention, the cost of the communication device can be reduced by reducing the cost of the antenna structure, and the frequency band of the antenna structure can be widened. This enables new development of communication equipment, such as an increase in the functions of communication equipment.

Brief Description of Drawings

FIG. La is a model diagram for explaining the antenna structure of the first embodiment.

[Figure lb] shows an example of the form of the radiation electrode and ground extension shown in figure la viewed from the back. FIG.

FIG. Lc is a model diagram showing one embodiment of a conductor plate for producing the radiation electrode and the ground extension shown in FIG. La.

Garden 2] is a side view of the antenna structure of the first embodiment.

Garden 3] A diagram for explaining an example of the manufacturing process of the radiation electrode constituting the antenna structure of the first embodiment.

FIG. 7 is a diagram for explaining a comparative example with respect to the antenna structure of the first embodiment. Garden 4b] is a model diagram showing one embodiment of a conductor plate for producing the radiation electrode and the ground extension shown in FIG. 4a.

FIG. 4c is a model diagram for explaining a current flow path of a ground extension portion constituting the antenna structure shown in FIG. 4a.

Garden 5a] is a view for explaining the ease of manufacturing the antenna structure of the first embodiment. Garden 5b] is a model diagram for explaining the difficulty in manufacturing the antenna structure shown in FIG. 4a

FIG. 6 is a view for explaining a modified example of the radiation electrode constituting the antenna structure of the first embodiment.

Garden 7] is a model diagram showing an example of an embodiment in which a reinforcing rib is provided in a ground extension of a radiation electrode.

FIG. 8a is a model diagram showing one example of a configuration of a conductor plate constituting the radiation electrode and the ground extension shown in FIG. 8b.

Garden 8b] is a model diagram showing another example of the form of the ground extension together with the radiation electrode.

FIG. 9 is a diagram for explaining an antenna structure according to a second embodiment.

Garden 10a] is a view for explaining another example of the radiation electrode of the antenna structure of the second embodiment.

Garden 10b] is a diagram for explaining still another embodiment of the radiation electrode of the antenna structure of the second embodiment.

Garden 1 la] is a diagram showing radiation electrodes constituting the antenna structure of the third embodiment.

Garden ib] An example of the radiation electrode and ground extension shown in Fig. 11a viewed from the back FIG.

FIG. 12 is a model diagram showing an antenna structure of a fourth embodiment.

FIG. 13a is a view for explaining a modification of the antenna structure of the fourth embodiment.

FIG. 13b is a model diagram showing an example of a state in which the radiation electrode and the ground extension shown in FIG. 13a are viewed from the back side.

FIG. 14 is a diagram for explaining another example of the power supply means for the radiation electrode.

FIG. 15a is a view for explaining another example of the shape of the radiation electrode.

FIG. 15b is a view for explaining still another example of the shape of the radiation electrode.

FIG. 16 is a side view showing an example of an embodiment in which a dielectric is provided on the radiation electrode.

FIG. 17 is a view for explaining another embodiment of the radiation electrode.

FIG. 18a is a diagram for explaining one of the antenna structures described in Patent Document 1.

FIG. 18b is a model diagram showing a form example of a conductor plate for producing the antenna structure shown in FIG. 18a.

Explanation of symbols

[0019] 1 Antenna structure

2 Board

3 Radiation electrode

4, 4 'ground extension

5 Conductor plate

8 Power supply electrode

14 ribs

15, 16, 17 Branch radiation electrode

18 Slit for splitting radiation electrode

22 Notch

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. La shows a schematic perspective view of the antenna structure of the first embodiment, and FIG. 2 shows a schematic side view of the antenna structure of the first embodiment. This first embodiment The antenna structure 1 includes a substrate 2 on which a ground portion (not shown) is formed, a radiation electrode 3 disposed at an end of the substrate 2, and a gap between the radiation electrode 3 and the ground portion of the substrate 2. And a ground extension 4 for connecting the two. The board 2 is a circuit board built in a wireless communication device such as a mobile phone.

[0022] The radiation electrode 3 is configured to have a main surface 3A and a rising portion 3B. An end S on the rising portion 3B side is a ground end, and an end on the main surface portion 3A side. Section K is an open end (opposite to the ground end). The ground extension 4 is connected to each side edge of the radiation electrode 3 on both sides on the ground end side, and passes through the position outside the radiation electrode 3 from the ground end side of the radiation electrode 3 to the radiation electrode 3. It is stretched in the direction of the force toward the open end side.

The radiation electrode 3 and the ground extension 4 are formed by pressing and bending a rectangular conductor plate 5 as shown in FIG. That is, by bending the conductive plate 5 at the position indicated by the dotted line in FIG. Lc, the conductive plate 5 is divided into a main surface portion 3A and a rising portion 3B, and the main surface portion 3A is formed on the substrate surface at one end of the substrate 2. They are arranged facing each other with an interval. The rising portion 3B is erected vertically across the substrate 2 at a position outside the end face of the substrate 2 on the side where the radiation electrode is formed.

[0024] Slits 6 (6a, 6b) are press-formed on the side edges Kl, K2 on both sides of the conductor plate 5, respectively.

(Punching). Here, the slit 6 has a shape formed by cutting from the side edge of the conductor plate 5 and extending toward the ground end side of the radiation electrode 3. In the first embodiment, a part of the side edges Kl, K2 on both sides of the conductor plate 5 is cut off from the radiation electrode 3 by the slits 6 (6a, 6b) to form a ground extension 4. The ground extension 4 has such a shape as to be inclined toward the substrate 2 with the connection point 7 with the radiation electrode 3 as a base point.

The first embodiment has a configuration in which the ground end side of the radiation electrode 3 is disposed so as to protrude below the substrate 2. In other words, the connection between the radiation electrode 3 and the ground extension 4 is located below the substrate 2. The ground extension 4 extends to the substrate 2 side in a direction perpendicular to the rising portion 3B of the radiation electrode 3 at the connection portion with the radiation electrode 3 and then rises along the end face of the substrate 2 on the radiation electrode formation side. The rising end is bent along the upper surface of the substrate 2 and connected to the ground portion of the substrate 2. The ground extension 4 and the substrate 2 may be joined using a joining material such as solder, for example, or may be joined by force using a force member. Further, for example, the entire antenna structure 1 may be housed and arranged in an end region of a housing (cover) 10 of the communication device as shown by a chain line in FIG. In the illustrated example, the main surface 3A of the radiation electrode 3 is configured to receive a downward pressing force from the cover 10, and the downward pressing force from the cover 10 pushes the entire radiation electrode 3 downward. Then, the ground extension 4 is connected to the upper surface of the substrate 2 by pressing contact. In this way, the ground extension 4 may be pressed and connected to the substrate 2. As described above, there are various methods for connecting the ground extension 4 and the substrate 2, and the connection method is not limited here.

FIG. Lb schematically shows an example of a state in which the radiation electrode 3 and the ground extension 4 shown in FIG. La are viewed from the lower side (back side). As shown in FIGS. La and lb, in the first embodiment, a part of the main surface 3A of the radiation electrode 3 is cut and raised toward the substrate 2, and the cut and raised portion causes the power supply electrode 8 to be cut. It is configured. A power supply pad (not shown) for connecting to a high-frequency circuit 11 for wireless communication of a communication device (see FIG. 2) is formed on the substrate surface at the end of the substrate 2 on which the radiation electrode is formed. 8 is connected to the power supply pad. The radiation electrode 3 is connected to a radio-frequency circuit 11 for wireless communication via the power supply electrode 8 and the power supply pad. In addition, the connection between the power supply electrode 8 and the power supply pad may be performed by soldering, or the connection method using the pressing connection using the pressing force from the cover 10 to the radiation electrode 3 as described above is limited. Not done.

For example, when a signal for transmission is supplied from the high-frequency circuit 11 for wireless communication to the radiation electrode 3 via the power supply electrode 8, the radiation supply 3 is supplied to the radiation electrode 3 by the signal supply, for example, as shown in FIG. A large current I flows in a loop from the ground extension 4 to the main surface 3A via the rising portion 3B of the radiation electrode 3, and the radiation electrode 3 is excited to transmit a signal for transmission wirelessly. When a signal arrives from outside to the radiation electrode 3 and the radiation electrode 3 is excited by receiving a signal, a received signal is transmitted from the radiation electrode 3 to the radio frequency circuit 11 for wireless communication via the power supply electrode 8.

[0029] The antenna structure 1 of the first embodiment is configured as described above. Next, an example of the manufacturing process of the radiation electrode 3 and the ground extension 4 constituting the antenna structure 1 of the first embodiment will be described. This will be described with reference to FIG. First, as shown in the Ml portion of the sheet metal 12, an outer peripheral portion of a region serving as the radiation electrode 3 and the ground extension 4 is punched out by press working. Next, as shown in the M2 part, slits 6 are formed by press working at the side edges Kl and K2 on both sides of the punched area, and the part to be the ground extension part 4 is formed. Separate from the part that will become the radiation electrode 3.

Thereafter, as shown in the M3 portion, the outer peripheral portion of the power supply electrode 8 is punched out by press working, and the power supply electrode 8 is cut and raised as shown in the M4 portion. Then, as shown in the M5 part, the ground extension part 4 is formed by bending a kneader using a mold. Next, the radiating electrode 3 is bent in the upright direction with the ground end side of the radiating electrode 3 as a base point, and then the bent and raised radiating electrode 3 is placed in the middle of the radiating electrode 3 as shown in the M6 portion. It is bent horizontally at the position to form the main surface 3A and the rising portion 3B of the radiation electrode 3. In this manner, the radiation electrode 3, the ground extension 4, and the power supply electrode 8 can be manufactured.

In the configuration of the first embodiment, for example, when the radiation electrode 3 and the ground extension 4 are viewed from above in FIG. La, the radiation electrode 3, the ground extension 4, and the power supply electrode 8 are mutually connected. It does not overlap. For this reason, the radiation electrode 3 can be manufactured by continuously processing the sheet metal 12 by press working and simple bending calorie as described above. This simplifies the manufacturing process of the antenna structure 1 and facilitates mass production of the antenna structure 1. In addition, since the mold used for the bending calorie has a simple shape, the time required for designing the mold can be reduced.

Further, in the first embodiment, one conductor plate is cut and the radiation electrode 3 and the ground extension portion are formed.

Since the power supply electrode 4 and the power supply electrode 8 are formed, the connection process between the radiation electrode 3 and the ground extension 4 is not required in the manufacturing process, and the connection process between the radiation electrode 3 and the power supply electrode 8 is also unnecessary. Furthermore, the antenna structure of the first embodiment is simply connected by connecting the leading end of the ground extending portion 4 produced as described above to the substrate 2 and connecting the leading end of the power supply electrode 8 to the substrate 2. Since the antenna 1 can be constructed, the assembling process of the antenna structure 1 is simple.

[0033] Further, since the connection between the radiation electrode 3 and the ground extension 4 and the connection between the radiation electrode 3 and the power supply electrode 8 are not made by using a joining material such as solder, for example, the radiation electrode 3 and the power supply electrode 8 are not connected. Rolling ground The problem of poor connection with the extension part 4 and the problem of poor connection between the radiation electrode 3 and the power supply electrode 8 can be avoided. Furthermore, it is possible to prevent a problem that the connection state between the radiation electrode 3 and the ground extension 4 and the connection state between the radiation electrode 3 and the power supply electrode 8 are varied, for example, the antenna characteristics are varied. Thereby, the reliability of the antenna structure 1 and the communication device including the antenna structure 1 can be improved.

By the way, it is conceivable to bend the conductor plate as shown in FIG. 4b along a dotted line to produce the radiation electrode 20 and the ground extension 21 as shown in the perspective view of FIG. 4a. Like the radiation electrode 3 of the first embodiment, the radiation electrode 20 has a main-ground portion 20A and a rising portion 20B. It is different from the ground extension 4. That is, in the configuration of the ground extension 4 shown in the first embodiment, a part of the side edge of the conductor plate 5 constituting the radiation electrode 3 is cut off by the slit 6 to form the ground extension 4. Have been. On the other hand, in the configuration shown in FIG. 4B, one end side of the conductor plate forming the radiation electrode 20 is extended in the direction in which the main surface portion 20A and the rising portion 20B are arranged, thereby forming the ground extension portion 21. For this reason, the configuration shown in FIGS. 4a and 4b requires an extended portion of the conductor plate (that is, the conductor plate portion forming the ground extension 21). As a result, the area of the conductor plate required for producing the radiation electrode and the ground extension is increased.

When the radiation electrode 20 is viewed from the side, the side view thereof is the same as the side view of the radiation electrode 3 (see FIG. 2). From this, if the sizes of the radiation electrodes 3 and 20 are equal, that is, the size of the main surface 3A and the main surface 20A, the size of the rising portion 3B and the size of the rising portion 20B are the same, and the size of the rising portion 3B is the same. If the distance between the rising portions 20B and the substrate 2 is equal to the distance between the rising portions 20B and the substrate 2, and if the protruding lengths of the rising portions 3B and 20B are equal, the radiation electrodes 3 and 20 The electrical volumes are approximately equal.

Furthermore, the width of the ground extension 4 in the first embodiment is smaller than that of the ground extension 21. For this reason, there is a possibility that the current flowing from the ground portion of the substrate 2 to the radiation electrode 3 through the ground extension portion 4 may be adversely affected, but it is as wide as the ground extension portion 21. Even so, the current flowing from the substrate 2 toward the radiation electrode 20 concentrates on the side edge of the ground extension 21 as shown in FIG. 4c. Because of this, this first Even if the frame-like thin grounding extension 4 is formed on both sides of the radiation electrode 3 as in the embodiment, the current flowing from the substrate 2 to the radiation electrode 3 through the grounding extension 4 has a large adverse effect. Can be prevented. In other words, there is no need to worry about deterioration of antenna characteristics due to the thin ground extension 4.

Therefore, the antenna structure 1 shown in the first embodiment has a smaller electric volume of the radiating electrode (antenna) due to a decrease in the electric volume of the radiating electrode and the like than the structure shown in FIG. 4A. It is possible to obtain an excellent effect that the production can be facilitated while suppressing the deterioration of the characteristics, and the area of the conductor plate required for manufacturing the radiation electrode can be largely reduced.

Further, for example, a radiation electrode 20 and a ground extension portion as shown in FIG. Assume that 21 is manufactured. In this case, for example, after bending the radiation electrode 20 in the upright direction with respect to the ground extension 21 as shown by the solid line in FIG. 5b, the metal fitting 26 as shown by the dotted line in FIG. The metal fitting 26 is disposed at the position shown by the dotted line in FIG. 4a, the metal fitting 26 cannot be arranged at the position indicated by the dotted line in the configuration shown in FIG. 4A because of the ground extension 21. For this reason, it is difficult to manufacture the thing shown in FIG. 4a using a press that bends the conductor plate by moving the metal fitting relatively to the conductor plate in the vertical direction.

On the other hand, in the antenna structure 1 of the first embodiment, after the radiation electrode 3 is bent and raised as shown by the solid line in FIG. 5A, the bending is performed without being obstructed by the ground extension 4. The metal fitting 26 can be arranged along the raised radiation electrode 3, and the main surface portion 3A of the radiation electrode 3 can be bent in the horizontal direction using the metal fitting 26 and can be folded. In other words, by providing the configuration in the first embodiment, the antenna structure 1 can be easily formed by using a press machine that moves the metal fitting in the vertical direction relative to the conductor plate to bend the conductor plate. Can manufacture power S.

In the example of FIG. 1, the side edge portions on both sides of the radiation electrode 3 (conductor plate 5) are respectively formed as ground extension portions 4. As a modification, for example, FIG. As shown, in addition to the ground extension 4 on the side edge of the conductor plate 5, the ground An additional ground extension 4 ′ separated from the radiation electrode 3 by a slit for forming an extension may be provided. By providing such an additional ground extension 4 ′, the reliability of connection between the ground extension 4 and the substrate 2 can be improved. In FIG. 6, the radiation electrode 3 and the ground extension portions 4 and 4 'are shown as viewed from the substrate 2 side (back side). In addition, there is a communication space Z (see FIG. La) outside the end face of the substrate 2 on the side where the radiation electrode is formed, that is, a space Z surrounded by the radiation electrode 3 and the ground extension 4. Parts of the machine, such as speed, may be located. When the additional ground extension 4 ′ is provided, the arrangement position and width of the additional ground extension 4 ′ are set in consideration of the arrangement of components in the space Z.

In the first embodiment, the ground extension 4 is much thinner than the radiation electrode 3. For this reason, deformation of the radius and torsion of the ground extension portion 4 may be a concern. In such a case, for example, as shown in the model diagram of FIG. 7, a rib 14 for reinforcing the bending strength may be provided on the side edge of the extension part 4 for grounding. The ribs 14 for reinforcing the bending strength can be produced by bending a projecting portion provided on a side edge portion of the ground extension portion 4.

Further, in the example of FIG. 1, the slit 6 for forming the ground extension provided in the conductor plate 5 extends toward the ground end side of the radiation electrode 3 after being cut from the side edge of the conductor plate 5. As shown in FIG. 8a, for example, the slit 6 is formed to extend from the open end side of the radiation electrode 3 to the ground end side along the side surface of the conductor plate 5 as shown in FIG. 8a. It may have a linear shape. The slit 6 separates the ground extension 4 from the radiation electrode 3 to form the antenna structure 1 as shown in the perspective view of FIG. 8B.

Note that the posture of the antenna structure 1 is not limited to the posture shown in FIG. 1, and the substrate 2 may be arranged in an upright position, or the main surface 3 A may be positioned below the substrate 2. In some cases, it is arranged in a location.

Hereinafter, a second embodiment will be described. In the description of the second embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and the description of the common portions will not be repeated.

In the second embodiment, as shown in the perspective view of FIG. 9, the radiation electrode 3 (conductor plate 5) has two radiation electrode dividing slits 18 (18a, 18b) spaced from each other. Is formed through. The slit 18a for dividing the radiation electrode is connected to the radiation electrode 3 (conductor plate 5) from the open end side. Along the side surface of the radiation electrode 3 toward the ground end. The slit 18b for splitting the radiation electrode has a shape in which the slit 18b is cut from the side end of the radiation electrode 3 and then acts on the ground end side of the radiation electrode 3 along the side surface of the radiation electrode 3.

The radiation electrode 3 is separated and divided into a plurality of branch radiation electrode portions 15, 16 and 17 by the radiation electrode dividing slits 18a and 18b. Each of the branch radiation electrode portions 15, 16, and 17 has a main surface 咅 B (15A, 16A, 17A) and a rising force 咅 B (15B, 16B, 17B). The parts 15, 16, 17 are connected to the ground extension parts 4 on both sides of the radiation electrode 3 at the base end (ground end side) of the rising part 3B (15B, 16B, 17B), respectively. Grounded to ground.

In the second embodiment, the power supply electrode 8 is formed by cutting and raising a part of the main surface portion 15A in one branch radiation electrode portion 15, and the branch radiation electrode portion 15 is of a power supply type. It is composed of a branch radiation electrode. The other branch radiation electrode sections 16 and 17 are non-feed type branch radiation electrode sections. The non-feed type branch radiation electrode sections 16 and 17 are electromagnetically coupled to the feed type branch radiation electrode section 15, respectively, and perform an antenna operation together with the branch radiation electrode section 15 to create a multiple resonance state.

In the second embodiment, the frequency band used for the wireless communication of the antenna structure 1 can be widened by the multiple resonance caused by the plurality of branch radiation electrode portions 15, 16, and 17. , Wireless communication in a plurality of different frequency bands can be made possible.

[0049] In the second embodiment, the radiation electrode 3 is formed with two slits 18 for dividing the radiation electrode. However, the frequency required by the size of the radiation electrode 3, the specifications, and the like are set. In consideration of the bandwidth, etc., one radiation electrode splitting slit 18 may be formed in the radiation electrode 3 to divide the radiation electrode 3 into two branch radiation electrode parts. The slit 18 for dividing three or more radiation electrodes may be formed to divide the radiation electrode 3 into four or more branch radiation electrode portions.

Further, in the second embodiment, the ground extension 4 is provided on both sides of the radiation electrode 3 (conductor plate 5), but as described in the first embodiment, The extension portion 4 for grounding may be provided not only on both side edges of the radiation electrode 3 but also an additional extension portion 4 ′ for grounding as shown in FIG. Further, in the example shown in FIG. 9, one of the plurality of branch radiation electrode sections 15, 16, and 17 is formed as a feed type branch radiation electrode section. Accordingly, as shown in the model diagram of FIG. 10a, a configuration may be adopted in which the power supply electrode 8 is provided in two or more of the plurality of branch radiation electrode units, and a plurality of power supply type branch radiation electrode units are provided. It should be noted that all the branch radiation electrode portions may be provided as a power supply type without providing the non-feed type branch radiation electrode portion.

Further, as shown in FIG. 10b, the end portion of the radiation electrode splitting slit 18 on the grounding end side may be arranged above the example of FIG. As a specific example, for example, the dimension H shown in FIG. 10b from the starting point of the rising portion 3B to the end of the radiation electrode dividing slit 18 is set to 0.5 mm or more. With such a configuration, the radiation electrode 3 with increased strength can be formed.

Hereinafter, a third embodiment will be described. In the description of the third embodiment, the same components as those of the first and second embodiments are denoted by the same reference numerals, and the description of the common portions will not be repeated.

FIGS. 11a and lib show schematic perspective views of radiation electrodes constituting the antenna structure of the third embodiment. In FIG. 11a, the emission electrode 3 is shown when viewed from above the substrate 2, and in FIG. 11b, the emission electrode 3 is shown when viewed from the side of the substrate 2 (back side). .

In the third embodiment, ground extension portions 4 are provided on both side edges of the radiation electrode 3 on the ground end side, and additional grounding is provided on the ground end side between both side edges of the radiation electrode 3. Extension section 4 'for the use is provided. Further, the radiation electrode 3 is provided with a cut portion 22 extending from the cut-and-raised space Q of the additional ground extension 4 ′ to the open end of the main surface portion 3A. The cut-and-raised space portion Q and the cut portion 22 form a radiation electrode dividing slit, and the radiation electrode 3 is divided and divided into a plurality of branch radiation electrode portions 15 and 16.

In the examples shown in FIGS. 11A and 11B, a power supply electrode 8 is provided on one of the plurality of branch radiation electrode portions 15 and 16 to form a power supply type, and the other side is provided with a power supply type. It is a non-powered type. A multi-resonance state is created by these feed-type and non-feed-type branch radiation electrode sections 15 and 16. Due to its multiple resonance state, a wide frequency band And wireless communication in a plurality of mutually different frequency bands becomes possible.

In the examples of FIG. 11a and FIG. 11b, one side of the plurality of branch radiation electrode portions 15 and 16 is a power supply type and the other side is a non-power supply type. The radiation electrode portions 15 and 16 may be of a power supply type.

Further, in the examples of FIGS. 11A and 11B, only one additional ground extension 4 ′ is formed by cutting and raising a part of the radiation electrode 3. In addition to providing an additional ground extension 4 ′, a cut-out portion 22 connected to the cut-and-raised space Q is provided for each cut-and-raised space Q of the additional ground-extended extension 4 ′, and the cut-and-raised space is provided. The radiation electrode 3 may be divided and divided into three or more branch radiation electrode portions by a radiation electrode dividing slit formed by the portion Q and the cutout portion 22. In this case, for example, by configuring each of the branch radiation electrode portions to resonate at a resonance frequency shifted from each other, the frequency bandwidth can be further widened, or a plurality of mutually different radiation electrodes can be formed. Wireless communication in different frequency bands can be enabled.

Hereinafter, a fourth embodiment will be described. In the description of the fourth embodiment, the same components as those in the first to third embodiments are denoted by the same reference numerals, and the description of the common portions will not be repeated.

In the antenna structure of the fourth embodiment, as shown in FIG. 12, a plurality of radiating electrodes 3 (3α, 3) are arranged side by side at one end of the substrate 2 with an interval therebetween. ing. At least one of the plurality of radiation electrodes 3 ( _3α , 3) has one of the radiation electrodes 3 shown in the first to third embodiments.

In the example of FIG. 12, a radiation electrode 3 (3 lines) of a type having a plurality of branch radiation electrode portions 15 and 16 shown in the second embodiment, and a modification of the radiation electrode 3 shown in the first embodiment. Type radiation electrode 3 (3β). The deformed type of the radiation electrode 3β is one side of the grounding end side of the radiation electrode 3β, which is different from the fact that the ground extension portions 4 are connected to both side edges on the grounding end side of the radiation electrode 3β. The ground extension 4 (4β) is connected only to the edge. Here, the radiation electrode 3β is a non-feed type in which the feeding electrode 8 is not provided, and is electromagnetically coupled with the feed type branch radiation electrode portion 15 of the radiation electrode 3a to create a multiple resonance state. Things. Further, instead of the configuration shown in FIG. 12, for example, a configuration as shown in FIG. 13A may be used. That is, in the example of FIG. 13A, a plurality of radiation electrodes 3 (3α, 3) of the type shown in the first embodiment are arranged side by side with an interval therebetween. One side of these juxtaposed radiation electrodes 3α and 3β is a feed type, and the other side is a non-feed type. FIG. 13B shows a state in which the radiation electrodes 3α and 3β shown in FIG. 13A are viewed from the substrate 2 side (back side). In the examples shown in FIGS. 13a and 13b, one of the radiation electrodes 3α and 3β is a power supply type, and the other is a power supply type. It may be a type.

In the fourth embodiment, as shown in FIGS. 13a and 13b, a plurality of radiation electrodes 3 of the same type shown in any one of the first to third embodiments are connected to each other. A configuration in which a plurality of different types of radiation electrodes shown in each of the first to third embodiments may be arranged in parallel may be used. At least one radiating electrode shown in the third embodiment and radiating electrodes having a configuration other than the configuration of the first and third embodiments may be arranged side by side with an interval therebetween.

In the case of a configuration in which a plurality of radiation electrodes of the same type or different types shown in the first to third embodiments are combined and arranged in parallel, the radiation electrodes arranged in parallel are as described above. By pressing and bending the sheet metal 12, it is possible to simultaneously produce the sheet metal 12 in a juxtaposed state.

Hereinafter, a fifth embodiment will be described. The fifth embodiment relates to a communication device. The communication device of the fifth embodiment is characterized in that any one of the antenna structures 1 shown in the first to fourth embodiments is provided. Since the description of the antenna structure 1 has been described above, the description thereof will not be repeated here. In addition, there are various configurations of the communication device other than the antenna structure, and the description of adopting any of the configurations is omitted here.

[0066] The present invention is not limited to the embodiments of the first to fifth embodiments, and may adopt various embodiments. For example, in each of the first to fifth embodiments, a part of the main surface portion 3A (15A) is cut and raised on the power supply type radiation electrode 3 (there is a branch radiation electrode portion 15) for power supply. Although electrode 8 was provided, feed-type radiation electrode 3 (branch radiation electrode section 15) was The means for connecting to the high-frequency circuit 11 of the communication device is not limited to the power supply electrode 8. For example, a power supply pin 23 made of a conductor as shown in the side view of FIG. 14 may be used. ,. The power supply pin 23 is connected to a power supply pad (not shown) for connecting a high-frequency circuit formed on the substrate surface of the substrate 2 and has a panel characteristic.

The position of the power supply electrode 8 formed by cutting and raising a part of the main surface 3A of the radiation electrode 3 is not limited. For example, the power supply electrode 8 may be formed at the rising portion 3B. The power supply electrode 8 may be formed by cutting and raising a part. The connection point between the power supply pin 23 and the radiation electrode 3 is not limited to the example of FIG. The feeding position of the radiation electrode 3 is appropriately set in consideration of impedance matching between the radiation electrode 3 and the high-frequency circuit 11, and the feeding position of the radiation electrode 3 is limited to the position shown in FIG. 14 or the like. It is not done.

Further, in each of the first to fifth embodiments, the extension end of the ground extension 4 is the force connected to the substrate 2. For example, the antenna structure shown in each of the first to fifth embodiments 1 is, for example, housed and arranged in the housing of a communication device, and the housing itself is made of a conductor such as a magnesium alloy, and can be regarded as ground, or the housing is made of an insulator made of resin or the like. When a conductor portion (ground portion) that functions as a ground is provided, instead of connecting the extension end of the ground extension 4 to the substrate 2, the extension end of the ground extension 4 is It may be connected to a housing that can function as a ground or a ground portion provided in an insulating housing, for example.

Further, in the examples shown in the first to fifth embodiments, as a method of connecting the radiation electrode 3 to the high-frequency circuit 11 side, a direct power supply system in which the radiation electrode 3 is directly connected via the power supply electrode 8 is used. However, a capacitive power supply system in which the radiation electrode 3 is connected to the high-frequency circuit 11 via a capacitor may be employed.

[0070] Further, when the antenna structure 1 is accommodated and arranged in, for example, an end region in the cover 10 of the communication device, the radiation electrode 3 is formed so that the electric volume of the radiation electrode 3 can be increased as much as possible. The shape may be, for example, along the inner wall surface of the end region in the cover 10 as shown in FIGS. 15A and 15B. That is, in the example of FIG. 15A, the rising force 3B is formed below the substrate 2 with respect to the main surface 3A, and a part of the main surface 3A conforms to the shape of the cover 10. To form a tapered surface. Further, in the example shown in FIG. 15B, the connecting portion between the main surface portion 3A and the rising portion 3B is formed as a round portion in conformity with the shape of the cover 10 which does not form a right angle.

Further, for example, when it is desired to reduce the size of the radiation electrode 3, as shown in the side view of FIG. 16, a dielectric 24 is partially or entirely provided on the surface of the radiation electrode 3 on the substrate 2 side. It may be provided. Due to the wavelength shortening effect of the dielectric 24, the size of the radiation electrode 3 can be reduced.

Further, for example, the dielectric 24 may be provided at a position between the branch radiation electrode portions of the radiation electrode 3 or between a plurality of radiation electrodes arranged in parallel. Furthermore, as shown in the side view of FIG. 17, the opposite end of the radiation electrode 3 from the ground end may be bent toward the substrate 2.

Industrial applicability

[0073] As described above, the present invention can provide an antenna structure that is small, low-cost, easy to improve in performance, and a communication device using the same. This is effective when applied to a communication device or the like and an antenna structure built therein.

Claims

The scope of the claims

[1] An antenna structure having a substrate on which a ground portion is formed and a radiation electrode made of a plate material that performs an antenna operation, one end of the radiation electrode being a ground end side, and The opposite end of the grounding end is disposed above the substrate along the board surface with a space between them, and at least both side edges on the grounding end side of the radiation electrode are respectively connected to the grounding end of the radiation electrode. And a ground extension extending toward the opposite end of the grounding end from the grounding end, and a leading end of the grounding extension is connected to the ground of the substrate. An antenna structure characterized by the following.

[2] The radiation electrode and the ground extension are configured to be housed and arranged inside a housing that can be regarded as ground, or inside a housing in which the ground is provided. Instead of connecting the base to the ground part of the board, the extension end of the ground extension part is connected to a housing that can be regarded as a ground or a ground part provided in the housing. 2. The antenna structure according to claim 1, wherein:

[3] A claim characterized in that an additional ground extension separated from the radiation electrode by a slit for forming a ground extension is provided on the ground end side between both end surfaces of the radiation electrode. The antenna structure according to 1.

[4] The ground end side of the radiation electrode is located outside the one end of the substrate, and the connection between the ground end side of the radiation electrode and the ground extension is located below the substrate. 2. The antenna structure according to claim 1, wherein the antenna structure is arranged, and the opposite end of the radiation electrode from the ground end is arranged above the substrate.

[5] The radiation electrode according to claim 1, wherein one or more radiation electrode division slits extending toward the ground end are formed, and the radiation electrode is divided into a plurality of branch radiation electrode portions. Antenna structure.

[6] At least one of the plurality of branch radiation electrode portions is formed as a feed type branch radiation electrode portion, and the other branch radiation electrode portions are formed as non-feed type branch radiation electrode portions. The branch radiation electrode portion of the type is configured to electromagnetically couple with the feed type branch radiation electrode portion to perform an antenna operation together with the branch emission electrode portion of the power supply type to create a multiple resonance state. 6. The antenna structure according to claim 5, wherein

[7] At one end of the substrate, a plurality of radiation electrodes are arranged side by side with an interval therebetween, and at least one of the plurality of radiation electrodes is defined in claim 1. An antenna structure comprising a radiation electrode having a configuration.

[8] At one end of the substrate, a plurality of radiation electrodes are arranged side by side with an interval therebetween, and at least one of the plurality of radiation electrodes is described in claim 5. An antenna structure comprising a radiation electrode having a configuration.

[9] A configuration in which a plurality of radiation electrodes are juxtaposed at one end of the substrate with an interval therebetween, and at least one of the plurality of radiation electrodes is defined in claim 6 An antenna structure comprising a radiation electrode having a configuration.

[10] A part of the radiation electrode is cut and raised toward the substrate, and the cut and raised portion forms a power supply electrode for connection to a high-frequency circuit connection power supply pad formed on the substrate. The antenna structure according to claim 1, wherein

[11] The power supply pad for connecting a high-frequency circuit is formed on the substrate surface, and the power supply pad and a radiation electrode located above the power supply pad are connected by a conductor having a panel characteristic. The antenna structure according to 1.

[12] The antenna structure according to claim 1, wherein a dielectric is provided on at least a part of the radiation electrode.

13. The antenna structure according to claim 1, wherein ribs for reinforcing bending strength are provided at side edges of the ground extension.

[14] A communication device provided with the antenna structure according to claim 1.