JP6183269B2 - Antenna device and portable wireless terminal equipped with the same - Google Patents

Description

  The present invention relates to an antenna device and a portable wireless terminal equipped with the antenna device.

  In recent years, mobile wireless terminals such as mobile phones have been increasingly multifunctional and high performance. In cellular communication, mounting of spatial multiplexing transmission (MIMO) is being started as a technique for realizing a high-speed and large-capacity wireless communication system. The MIMO system has a plurality of antennas for both transmission and reception, and simultaneously transmits different data at the same frequency from the respective antennas on the transmission side, and receives and synthesizes them by the plurality of antennas to quasi-widen the bandwidth. Realized. As a result, the transfer rate can be improved and large-capacity communication can be performed.

  In a MIMO system, two or more antennas that operate at the same frequency are used. When a plurality of antennas that operate at the same frequency band are configured on a substrate of a relatively small portable wireless terminal such as a mobile phone, the antennas are used. There is a problem that mutual coupling is very likely to occur. When the mutual coupling between the antennas is large, the antennas interfere with each other. Specifically, the isolation characteristics between the antennas deteriorate and the correlation between the radiation patterns becomes strong. These deteriorate the performance of the MIMO system and cause a failure to obtain a sufficient communication speed.

  As a general solution to this problem, a method of sufficiently separating the antennas on the substrate is known. However, the interior of a portable wireless terminal such as a cellular phone is mounted with high-density components, and it is difficult to place the components apart from each other due to space limitations. There is a problem that the size of the terminal is increased, the size of the terminal is increased, and the design and portability are impaired.

  Therefore, the present inventors have proposed a method of operating a single antenna element as two antennas that ensure sufficient isolation from each other. As described in Patent Document 1, by connecting two feeding points in different forms to a single antenna element provided on a substrate, each feeding point is operated as a different antenna, and the antenna This is a method of avoiding mutual coupling.

JP2013-258649A

  However, the antenna device described in Patent Document 1 has the following problems.

  In the method of Patent Document 1, the first feeding point 11 is provided on the second conductor 2 constituting the antenna device, and the second feeding point 12 is provided on the third conductor 3 (see FIG. 2). In the example of FIG. 2, the feeding point 12 is installed in the middle of the third conductor. When the second feeding point 12 is installed at the position of the virtual plane 10, the signals fed from the most feeding points are distributed perpendicularly to each other, so that the most ideal isolation can be secured. However, since the third conductor is formed by a single line in both paths from the feeding point to the ground area, the second feeding point 12 is placed on the substrate in order to install the second feeding point 12 at the position of the virtual plane 10. An electric signal transmitted from the wireless circuit is supplied by supplying a separate feeder line, or is fed in opposite phases from both ends of the third conductor on a different surface from the first feeding point, Since the feeding point 12 is arranged at the position of the virtual plane 10, the structure is complicated, and the feeding point is on both sides of the substrate. Therefore, the matching circuit elements must be arranged on both sides, and further miniaturization and It was an obstacle to cost reduction.

  Therefore, the second feeding point 12 is generally installed at either end of the third conductor. Although the symmetry of the antenna device having the imaginary plane 10 of the antenna device as a symmetry plane is slightly broken, the isolation and frequency characteristics are deteriorated although it is practically usable.

  The present invention has been made in view of the above situation, and it is possible to provide a simple configuration without providing a new large component for avoiding mutual signal interference between two or more antennas operating at the same frequency. It is easy to manufacture in an antenna device that operates as two antennas with a single antenna element, and can be applied to multi-bands. An object of the present invention is to provide an antenna device that can easily reduce mutual interference of signals and ensure high isolation characteristics, and a portable wireless terminal equipped with the antenna device.

  In order to achieve the above object, an antenna device according to the present invention includes a substrate having a ground region and a non-ground region, and first, second, and third conductors, and the first conductor is separated from the ground region. The second conductor includes a first feeding point on the substrate surface, one end is connected to the feeding transmission line, and the other end passes through the through conductor to the substrate backside. The third conductor includes a second feeding point at a predetermined position on the surface of the substrate, at least a part thereof faces the first conductor, and the second conductor when viewed in plan from above the substrate. Orthogonal to the conductor, one end side is connected to the ground conductor, the other end side has a non-live line and a live line, the non-live line is connected to the ground region, the live line is The first characteristic is that it is connected to a power transmission line provided in the ground area. To.

  In addition, the predetermined position said here represents the vicinity where the 2nd, 3rd conductor crosses by the top view on the symmetrical line of the antenna apparatus which makes a substantially line symmetry.

According to the antenna device having the above characteristics, the first feeding point operates as a feeding point for a monopole antenna having the first conductor and the second conductor as a radiation conductor, and the second feeding point is the first feeding point from a predetermined position. Since each of the feed points is on the almost symmetrical line of the antenna device and the signal distribution directions are orthogonal, the electric power that passes through the ground region regardless of the frequency. The mutual interference of signals is also suppressed, and the isolation between the two feeding points is improved.

  In this way, when the power is fed from two feeding points, the excitation directions are orthogonal to each other, and the current and voltage distribution on the polarization direction and ground region conductors are very different without depending on the frequency. The correlation coefficient of the radiation intensity in each direction of each radiation pattern when power is supplied from the point becomes small.

  Furthermore, according to the antenna device having the above characteristics, since the second and third conductors are orthogonal to each other, the mutual interference of signals due to electric field coupling between the second and third conductors is very high in a wide frequency region. As a result, the isolation characteristic is further improved.

Furthermore, since the second conductor is formed from the first feeding point to the first conductor and is formed as a through conductor around the back surface of the substrate, both the first and second feeding points must be installed on the surface of the substrate. The matching circuit element can be easily mounted.

The second feature is that at least a part of the third conductor faces the first conductor.

Since such a configuration is adopted, the third conductor and the first conductor form a strong magnetic field coupling, and the second feeding point efficiently operates the first conductor as a dipole antenna. .

Further, in the antenna device according to the present invention, the first feeding point is also installed in the vicinity of the predetermined position, and the second conductor has a non-hot-wire side line and a hot-wire side line from the first feeding point to the ground region. The third feature is that the non-live line is connected to the ground region, and the live line is connected to a power transmission line provided on the substrate.

  According to the antenna device having the above characteristics, two sets of matching circuits are concentrated at a predetermined position of the antenna device, and different excitation is performed from one point. Therefore, an effect of suppressing higher mutual interference can be obtained, and higher isolation can be obtained. Characteristics are obtained.

  Furthermore, the antenna device according to the present invention is characterized in that the matching circuit related to the first and second feeding points is constituted by a module in which at least a plurality of reactance elements are formed in a multilayer substrate.

  According to the antenna device having the above characteristics, when a large number of reactance elements are mounted, characteristic deterioration due to element variations, mounting variations, and self-resonant frequency variations can be reduced. In particular, when handling multiband or wideband characteristics, it is possible to arrange and design reactances considering the frequency characteristics of the elements.

  Furthermore, the portable wireless terminal according to the present invention has a fifth feature that the antenna device of the present invention is mounted. If the configuration is homogeneous, the best isolation and correlation can be obtained when the feeding point is installed on the symmetry line of the antenna device. However, in an actual mobile terminal, the position for obtaining the best isolation and correlation is not always on the symmetry line of the antenna device depending on the material and arrangement of components other than the antenna device. In the antenna device of the present invention, the predetermined position where the feeding point is arranged can be set relatively freely by the live line and the non-live line, so that the feeding point can be arranged on a symmetrical line considering the entire mobile terminal.

  According to the portable wireless terminal having the above characteristics, the antenna characteristics of the portable wireless terminal can be improved in a wide frequency band, and the size can be reduced.

  According to the present invention, a plurality of UHF or SHF widebands adapted to multibanding are provided without newly providing a component for reducing mutual signal interference between two or more antennas operating at the same frequency. In this frequency band, it is possible to reduce the mutual interference of signals between feed points, and to provide an antenna device that can secure high isolation characteristics and a portable wireless terminal equipped with the antenna device.

1 is a perspective view showing an antenna device according to Embodiment 1. FIG. It is an enlarged view of a top view showing details of a power feeding part of the antenna device according to the first embodiment. FIG. 3 is a detailed perspective view of a feeding portion showing the antenna device according to the first embodiment. FIG. 3 is a detailed top view in which a matching circuit element is mounted on the power feeding unit of the antenna device according to the first embodiment. FIG. 3 is a detailed perspective view in which a matching circuit element is mounted on a feeding portion of the antenna device according to the first embodiment. 6 is a perspective view showing an antenna device according to Embodiment 2. FIG. FIG. 6 is an enlarged view of a top view showing details of a power feeding part of an antenna device according to a second embodiment. FIG. 6 is a detailed perspective view of a feeding portion showing an antenna device according to a second embodiment. FIG. 10 is an enlarged view of a top view showing details of a power feeding part of an antenna device according to Embodiment 3. FIG. 6 is a detailed perspective view of a feeding portion showing an antenna device according to a third embodiment. It is a perspective view which shows the antenna device which concerns on Embodiment 4. It is an enlarged view of the perspective view which shows the electric power feeding part detail of the antenna apparatus which concerns on Embodiment 4. FIG. FIG. 4 is an electrical characteristic diagram of the antenna device according to Example 1 in a frequency band of 2 GHz to 3 GHz. FIG. 6 is an electrical characteristic diagram of the antenna device according to Example 1 in a frequency band of 5 GHz to 6 GHz. FIG. 6 is an electrical characteristic diagram of the antenna device according to Example 2 in a frequency band of 2 GHz to 3 GHz. It is an electrical property figure in the frequency band 5 GHz-6 GHz of the antenna apparatus which concerns on Example 2. FIG.

  DESCRIPTION OF EMBODIMENTS Embodiments (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the constituent elements described below can be appropriately combined.

  Further, in the following description of the present invention, it is assumed that the feeding points are adjusted using lumped constant elements or reactances formed in the modules so as to be matched to 50Ω, and matching is ensured. However, in practice, the feeding point is not limited to 50Ω as long as matching is achieved.

  In addition, the conductors that make up the line are drawn as if they were made of a circuit board pattern. For example, the non-live line and the live line are formed by a continuous coaxial cable from the radio circuit. It does not matter. In order to simplify the drawing, the line widths of the live line side line and the non-live line side line are drawn substantially the same, but details such as the line width of the non-live line side line are actually wide are omitted. Has been.

(Embodiment 1)
FIG. 1 is a perspective view illustrating an antenna device according to the first embodiment. FIG. 2 is a top view illustrating details of a power feeding unit of the antenna device according to the first embodiment. FIG. 3 is a perspective view illustrating details of a power feeding unit illustrating the antenna device according to the first embodiment. FIG. 4 is a top view showing details of a state in which the matching element is mounted on the feeding portion of the antenna device according to the first embodiment. FIG. 5 is a perspective view illustrating details of a state in which the matching element is mounted on the feeding portion of the antenna device according to the first embodiment. In FIGS. 1, 2 and 3, the matching circuit is omitted to clearly show the feeding point, but in reality, between the transmission line connecting the feeding point from the wireless circuit device on the circuit board and the antenna device, In general, there is impedance mismatch, and a matching circuit using reactance elements as shown in FIGS.

  The external dimensions of the substrate 101 are 92 mm × 40 mm, and the thickness is 1 mm. As shown in FIGS. 1, 2, and 3, the substrate 101 having the ground region 201 and the non-ground region 202, the first conductor 1, the second conductor 2, and the third conductor 3, The conductor 1 is a non-ground region 202 where the ground region 201 on the back surface of the substrate 101 is not formed, and is arranged in parallel with the boundary line between the ground region and the non-ground region. The second conductor 2 is the first power supply. One end including the point 11 is connected to the power transmission line 21 in the ground region 201, the other end is connected to the opposite surface of the substrate 101 at a predetermined position by the through hole 23, connected to the first conductor 1, and the third The conductor 3 includes a second feeding point 12 at a predetermined position, at least a part thereof faces the first conductor 1, and both ends are connected to the ground region 201.

  Further, one of the third conductors is directly connected to the ground region 201 when viewed from the second feeding point 12, and the other has a non-live line and a live line, and the non-live line 3- “b” is connected to the ground region 201, and the live-line 3-a is connected to a power transmission line 22 that leads to a signal source installed in the ground region.

  Further, although omitted in FIGS. 1, 2, and 3, a reactance element 31 for configuring a matching circuit as shown in FIGS. Since these elements are all arranged on the same surface, mounting is easy.

  With this configuration, the first feeding point 11 and the first conductor 1 are connected by the second conductor 2, and the second feeding point 12 and the first conductor 1 are connected by the conductor. Instead, power is fed in a non-contact state by magnetic field coupling around the location where the first conductor and the third conductor face each other. For this reason, there is no signal transmission path via the conductor between the first feeding point 11 and the second feeding point 12, so that mutual interference of signals can be suppressed.

  Further, the first feeding point 11 operates as a feeding point for the monopole antenna having the first conductor 1 and the second conductor 2 as radiation conductors, and the second feeding point 12 serves as the radiation conductor for the first conductor 1. Since the current and voltage distributions on the ground region conductors when excited from the respective feeding points are different, mutual interference of signals via the ground region 201 can be suppressed. By these effects, mutual interference between feeding points is suppressed, and isolation is improved.

  Furthermore, in this embodiment, as shown in FIGS. 1, 2, 3, and 4, 5, the live conductor side line for feeding and the non-hot line side line of the third conductor 3 that feeds power to the second feeding point 12 are the second. Therefore, the second feeding point 12 can be installed at a predetermined position including the matching circuit.

  With this configuration, the excitation of the first conductor 1 by the third conductor 3 does not break the symmetry with respect to the symmetry line of the antenna device passing through a predetermined position, and therefore power is fed in a wide frequency band. Mutual interference between points is suppressed and isolation is further improved.

(Embodiment 2)
FIG. 6 is a perspective view of the antenna device according to the second embodiment. FIG. 7 is a top view illustrating details of a power feeding unit of the antenna device according to the second embodiment. FIG. 8 is a perspective view illustrating details of a power feeding unit illustrating the antenna device according to the second embodiment. Although a state in which a matching circuit element for clarifying the feeding point is omitted is not illustrated, the feeding point is provided as in the first embodiment. The external dimensions of the substrate 101 are 96 mm × 40 mm, and the thickness is 1 mm. The shape of the inner ground conductor 201 is 86 mm × 40 mm. The second embodiment is different from the first embodiment in that the ground region 201 is a notch having a depth D and a width W as viewed from a predetermined position, which is a line-symmetric non-ground region having the second conductor 2 as a center line. 5 and the third conductor 3 is different in that it is positioned so as to straddle the opening of the notch 5.

  By configuring in this way, the influence of the magnetic flux generated around the third conductor 3 being hindered by the ground region 201 is reduced, and the magnetic coupling between the first conductor 1 and the third conductor 3 is further enhanced. Become. Further, by adjusting the depth D of the notch 5, the coupling strength can be adjusted, and the frequency bandwidth of the second feeding point 12 can be adjusted. Further, by providing the notch 5, the ground region 201 is also strongly excited in the same manner as the radiating conductor, and the antenna radiation efficiency is improved.

  Further, the first feeding point 11 is installed in the vicinity of the predetermined position, and the second conductor 2 has a non-live line and a live line from the bottom of the notch 5 to the feeding point 11. Furthermore, it is different from the first embodiment in that it is connected from the feeding point 11 to the first conductor. The non-hot-wire side line 2-b is connected to the ground region 201, and the hot-wire side line 2-a is connected to the feed transmission line 21 at the bottom of the notch 5.

By comprising in this way, the 1st feeding point 11 and the 2nd feeding point 12 can be concentrated on a predetermined position. Further, matching circuits related to the respective feeding points are also concentrated at predetermined positions. Since different excitation is performed from one point, an effect of suppressing high mutual interference can be obtained in a wider frequency range, and higher isolation characteristics can be obtained.
(Embodiment 3)
FIG. 9 is a top view of details of a power feeding unit of the antenna device according to the third embodiment. FIG. 10 is a perspective view of the details of the power feeding unit of the antenna device according to the third embodiment. The third embodiment is different from the second embodiment in that each reactance element constituting the matching circuit is formed as a module 41 on one chip.

  By configuring in this way, each built-in reactance element is designed based on the constants necessary as a matching circuit. Therefore, the characteristic due to self-resonance is higher than when mounted using a general-purpose chip inductor, chip capacitor, or the like. This is advantageous for deterioration and mounting variation.

Of course, it is possible to prepare a module for each feeding point individually or only on one side, but it is disadvantageous in terms of cost, so only one side is modularized if necessary. .

Since one type of module is compatible with different types of portable wireless terminals, the part that corrects antenna characteristics that are susceptible to the surrounding environment is externally attached, or the element in the module and the external element are jointly used. You may make it set a characteristic by.

(Embodiment 4)
FIG. 11 is a perspective view illustrating an antenna device according to the fourth embodiment. FIG. 12 is a perspective view of the details of the power feeding unit of the antenna device according to the fourth embodiment. A difference from the antenna device according to the third embodiment shown in FIGS. 9 and 10 is that the first feeding point 11 and the second feeding point 12 and the conductors 1, 2, 3, and the cutouts related to the two feeding points. 5 is different in that it is arranged not at the center of the side of the substrate 101 but at the corner of the substrate 101. For this reason, the non-ground region 202 is also arranged at the corner of the substrate 101 and has a small area and a narrow bandwidth of each band. Therefore, as a countermeasure, the fourth conductor 4 is sandwiched between the substrate 101 and the first conductor 1. Another difference is that they are installed facing each other.

  In the present embodiment, at the corner of the substrate 101, the two sides sandwiching the corner and the second conductor are arranged at an angle of approximately 45 degrees.

  With this configuration, the strict symmetry of the antenna configuration including the ground portion 201 is broken except when the ground portion 201 excluding the antenna device portion of the substrate 101 is square or rhombus. However, since the influence of the ground portion of the substrate related to the antenna characteristics decreases as the distance from the periphery of the feeding point increases, the characteristics are not substantially deteriorated.

  Furthermore, by adopting such a configuration, the circuit board component placement and space efficiency of the radio apparatus using the antenna apparatus are greatly improved. The external dimensions of the substrate 101 of this embodiment are 110 mm × 50 mm, and the thickness is 1 mm. The space of the antenna part is 13 mm × 13 mm including the notch 5.

  In the above-described antenna device of the present invention, the ground conductor 201 may be formed of a ground pattern formed on a dielectric substrate, or may be formed of a metal casing of a portable wireless terminal. The first conductor 1, the second conductor 2, and the third conductor 3 are described as conductor patterns arranged in the non-ground region 202 on the substrate 101, but the first conductor and the second conductor 3 Part of the conductor may be composed of an FPC conductor pattern or the like disposed on a base made of dielectric or magnetic material, or may be composed of a conductor pattern directly formed on the casing of the portable wireless terminal. It does not matter even if it is configured to be self-supporting with a sheet metal or the like.

  Hereinafter, the present invention will be described in more detail on the basis of specific examples. However, the present invention is not limited to the following examples, and may be appropriately modified and implemented without departing from the scope of the present invention. Is possible.

The simulation results of the electrical characteristics and electromagnetic field distribution in the description of the present invention are the results obtained with HFSS version 15 of Ansys. The correlation coefficient ρ indicating the mutual interference of the radiation patterns appearing in the present invention is the following from the result of the far-field radiation intensity in each direction of each radiation pattern when feeding from each feeding point obtained in the above simulation. This is calculated by the equation (1).

  In Equation (1), аθ and аφ are the declination θ component and φ component of the electric field intensity in the far field when power is fed from the first feeding point, respectively, and bθ and bφ are fed from the second feeding point, respectively. This is the declination θ component and φ component of the far-field electric field strength. m and n indicate the number of samplings of the electric field intensity in each direction of the deflection angles θ and φ, respectively. * Indicates a conjugate complex number.

Example 1
At the time of the simulation of the first embodiment, the external dimensions of the FR4 (relative dielectric constant = 4.4) substrate 101 are 92 mm × 40 mm and the thickness is 1 mm. Each conductor is all copper foil. The inner ground conductor 201 is 82.5 × 40 mm. The first conductor is a non-ground forming portion of the substrate and is formed on the lower surface of the substrate 106 at a distance of 9 mm from the ground portion, and has a width of 1 mm and a length of 15 mm.

  The second conductor 2 has a first matching circuit composed of a power transmission line 21 and a reactance element 31 that are connected to a radio circuit on the substrate at one end of the boundary line between the ground region and the non-ground region of the substrate 101. The other end is connected to the first conductor 1 by passing through the through hole at the predetermined position. One end of the third conductor 3 is connected to the ground region, extends from the ground region to a right angle of 3.5 mm, bends at a right angle, and extends 4.3 mm toward the center line of the antenna device. A non-hot-wire side line and a live-line side line for feeding power to the matching circuit from the feeding point 12 comprising the second matching circuit portion constituted by 31, with respect to the center line of the antenna device The non-live line side line is formed in a line-symmetric shape, and the live line side line is connected to the ground region 201, and the live line side line is connected to the feed transmission line 22 connected to the radio circuit on the substrate.

  Since the effect of the configuration of this embodiment can be obtained regardless of the frequency, the antenna device can be configured in a wide frequency band where matching is obtained by the matching circuit. In this embodiment, four reactance elements are arranged on the first feeding point side, and three reactance elements are arranged on the second feeding point side, so that a frequency band of Wi-Fi (registered trademark) / Bluetooth (registered trademark) is provided. Impedance adjustment is performed so as to achieve matching in two frequency bands of 2.4 GHz to 2.5 GHz which is a frequency band of 5.15 GHz to 5.725 GHz which is a frequency band of Wi-Fi (registered trademark).

  The characteristics of the antenna device thus obtained are shown in FIGS. FIG. 13 is an electrical characteristic diagram in the frequency band 2 GHz to 3 GHz of the antenna device according to the first embodiment, and FIG. 14 is an electrical characteristic diagram in the frequency band 5 GHz to 6 GHz. 13 and 14, reference numeral 51 denotes a return loss characteristic viewed from the first feeding point 11, 52 denotes a return loss characteristic viewed from the second feeding point 12, and 53 denotes a case where feeding is performed from the first feeding point 11. , 54 is the radiation efficiency when power is fed from the second feeding point 12, and 55 is the isolation characteristic between the first feeding point 11 and the second feeding point 12. The calculated value of the correlation coefficient ρ of the radiation pattern was 0.12 at 2.44 GHz, and the calculated value of the correlation coefficient ρ of the radiation pattern was 0.10 at 5.49 GHz.

(Example 2)
When the simulation of the third embodiment is performed, the external dimensions of the FR4 (relative dielectric constant = 4.4) substrate 101 are 96 mm × 40 mm, and the thickness is 1 mm. Each conductor is all copper foil. The shape of the inner ground conductor 201 is 86 mm × 40 mm. The notch 5 of the conductor is formed as a non-ground region in the center of the short side in contact with the non-ground region 202 of the ground conductor 201, and the shape of the notch 5 is a rectangular shape having a depth D = 3.5 mm × width W = 9 mm. It is. The first conductor is a non-ground forming portion of the substrate and is formed on the lower surface of the substrate 101 at a distance of 6 mm from the ground portion, and has a width of 1 mm and a length of 17.5 mm.

The second conductor 2 and the third conductor 3 are configured as described in the third embodiment, and a matching circuit module 41 including a matching circuit in a ceramic multilayer substrate is installed at a predetermined position. The outer shape of this module is so-called 201205 (2 mm × 1.2 mm × 0.5 mm).

  Each feeding point is 2.4 GHz to 2.5 GHz which is a frequency band of Wi-Fi (registered trademark) / Bluetooth (registered trademark) and 5.15 GHz to 5.GHz which is a frequency band of Wi-Fi (registered trademark). Impedance adjustment is performed by a matching unit module including a plurality of lumped constant elements in order to achieve matching in two frequency bands of 725 GHz.

FIG. 15 is an electrical characteristic diagram in the frequency band 2 GHz to 3 GHz of the antenna device according to the second embodiment, and FIG. 16 is an electrical characteristic diagram in the frequency band 5 GHz to 6 GHz. 15 and 16, 51 is a return loss characteristic viewed from the first feeding point 11, 52 is a return loss characteristic viewed from the second feeding point 12, and 53 is a case where feeding is performed from the first feeding point 11. , 54 is the radiation efficiency when power is fed from the second feeding point 12, and 55 is the isolation characteristic between the first feeding point 11 and the second feeding point 12. The calculated value of the correlation coefficient ρ of the radiation pattern was 0.11 at 2.44 GHz and 0.05 at 5.49 GHz.

By adopting the configuration of the antenna device as in the first or second embodiment according to the first or third embodiment, the first feeding point 11 is a mono conductor having the first conductor 1 and the second conductor 2 as radiation conductors. Since the second feeding point 12 operates as a feeding point for a dipole antenna having the first conductor 1 as a radiation conductor, the direction of resonance when excited from each feeding point is different. Therefore, mutual interference of signals passing through the ground region 201 can be suppressed. Therefore, without providing new components to reduce mutual coupling, high isolation characteristics in multiple frequency bands, and the relationship between the radiation intensity for each direction of each radiation pattern when feeding from each feeding point It has been confirmed that an antenna device having a reduced number of characteristics and ensuring radiation efficiency can be configured.

  As described above, since the antenna device of the present invention and a portable wireless terminal equipped with the antenna device can form a plurality of antennas that have small signal mutual interference and can be made small and multiband, portable wireless terminals such as cellular phones. Useful for.

DESCRIPTION OF SYMBOLS 1 1st conductor 2 2nd conductor 2-a hot wire side line 2-b non hot wire side line 3 3rd conductor 3-a hot wire side line 3-b non hot wire side line 4 4th conductor 5 notch 11 first feeding point 12 second feeding point 21 feeding transmission line on the first feeding point 22 feeding transmission line on the second feeding point 23 through conductor 31 reactance element 41 matching unit module 51 first Return Loss Characteristic as Seen from the Feed Point of 52 52 Return Loss Characteristic as Seen from the Second Feed Point 53 Radiation Efficiency when Inputting to the First Feed Point 54 Radiation Efficiency when Entering to the Second Feed Point 55 First Isolation characteristics between the feed point and the second feed point 101 substrate 201 ground region 202 non-ground region D depth of the notch 5 W width of the notch 5

Claims (5)

  A substrate having a ground region and a non-ground region; and first, second, and third conductors, wherein the first conductor is disposed away from the ground region, and the second conductor is a first conductor One end of which is connected to the transmission line on the first feeding point side provided in the ground region, and the other end moves to a different plane from the third conductor via a through conductor. 3 is connected to the first conductor orthogonal to the top view, the third conductor includes a second feeding point, one end is connected to the ground region, and the other end is a non-live line. A non-live line side line is connected to the ground area, and the live line side line is connected to a transmission line on the second feeding point side provided in the ground area. An antenna device comprising:   The antenna device according to claim 1, wherein at least a part of the third conductor faces the first conductor.   One end of the second conductor is connected to the transmission line on the first feeding point side, the first feeding point is included, and the other end is connected to the first conductor. From the first feeding point, The transmission line on the first feeding point side has a non-live line and a live line, the non-live line is connected to the ground area, and the live line is provided in the ground area. The antenna device according to claim 1, wherein the first feeding point is disposed in the immediate vicinity of the second feeding point, connected to the transmission line on the second feeding point side.   4. The matching circuit according to claim 1, wherein at least the matching circuit related to the first or second feeding point is configured by a module in which a plurality of reactance elements are formed in a multilayer substrate. Antenna device. A portable wireless terminal comprising the antenna device according to any one of 1 to 4 above.

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