JP5789777B2 - Mobile terminal device - Google Patents

Description

  The present invention relates to a portable terminal device having an antenna element.

  With the thinning of the mobile terminal device and the narrowing of the front screen, a metal frame (conductive member) for securing the strength may be provided on the side surface of the casing of the device. For decoration purposes, a metal frame may be provided on the side surface of the casing of the mobile terminal device.

  In recent years, in a mobile terminal device that employs a non-contact type touch panel, a metal frame may be provided on the side surface of the housing so that good detection performance of the touch panel can be obtained.

  The characteristics of the antenna element may be deteriorated by arranging a conductor nearby. Therefore, when the metal frame is arranged on the side surface of the housing, it becomes a problem how to arrange the antenna elements so as to obtain desired antenna characteristics.

  2. Description of the Related Art Conventionally, a wireless module has been proposed in which a conductor parallel to one side of a circuit board is provided to improve antenna characteristics and increase the bandwidth (see, for example, Patent Document 1).

  Conventionally, a technique of printing a conductor on a casing to make an antenna element has been generally used (see, for example, Patent Document 2).

Japanese Patent No. 4146478 JP 2007-288360 A

  However, in the technique of Patent Document 1, it is disclosed that a conductor provided in parallel with one side of a circuit board is disposed on a surface facing a human body, and the effect of the conductor is reduced when the human body approaches. was there. In particular, when the human body comes into contact with the conductor, there is a problem that the antenna performance is greatly deteriorated, and the directivity of the antenna element is greatly changed, so that the gain at the desired directivity is greatly reduced.

  For example, a GPS (Global Positioning System) receiving antenna is desired to have a large receiving gain in the zenith direction while holding the mobile terminal device by hand, but such directivity is greatly disturbed. become.

  Therefore, the antenna technology of Patent Document 1 cannot be effectively applied when a metal frame is arranged on the side surface of the housing.

  The objective of this invention is providing the portable terminal device which can acquire a desired antenna characteristic, even if a conductive member is provided in the housing | casing side surface.

  A mobile terminal device according to an aspect of the present invention includes a housing, a circuit board accommodated in the housing, and a ground formed so as to spread over the circuit board and / or other members in the housing. A conductive member having a length extending from substantially one end to the other end in the longitudinal direction of the casing, disposed on a side portion along the longitudinal direction of the casing, at least one antenna element, and the circuit A power supply section to which a substrate and the antenna element are connected, and the ground is substantially the same length as the conductive member, and the conductive member is connected to a region near the end in the longitudinal direction of the ground. Take the configuration.

  The portable terminal device of the present invention is mounted on a housing, a circuit board provided in the housing, an antenna provided in the housing and electrically connected to the circuit board, and the circuit board, A wireless circuit unit that feeds power to the antenna, and a first conductive member that is at least partially exposed from the casing and is disposed near one end of the casing and capacitively coupled to the circuit board, The first conductive member is electrically connected to the circuit board at the non-gripping portion.

  According to the present invention, desired antenna characteristics can be obtained in a configuration in which a conductive member is disposed on a side surface of a housing.

1 is an exploded perspective view showing the entirety of a mobile terminal device according to a first embodiment of the present invention. 2A is a plan view showing the upper end surface of the housing, FIG. 2B is a plan view showing the back surface of the housing, and FIG. 2C is a plan view showing the lower end surface of the housing. Schematic diagram showing a cross section of the side part of the casing in which the conductive member is assembled. Side view showing a housing with a conductive member assembled The figure explaining the electrical connection structure of the antenna element printed on the housing | casing and a circuit board (A) Rear view and (B) Right side perspective view schematically showing a configuration related to antenna characteristics in the mobile terminal device of the first embodiment. The disassembled perspective view which showed typically the structure regarding an antenna characteristic in the portable terminal device of Embodiment 1. FIG. The top view which showed typically the structure in connection with an antenna characteristic in the portable terminal device of Embodiment 1. View of the arrangement relationship between antenna elements and conductors from above View of rear view of antenna element and conductor arrangement (A) Rear view and (B) Right side perspective view schematically showing a configuration related to antenna characteristics in the mobile terminal device of the second embodiment. (A) Rear view and (B) Left side perspective view schematically showing a configuration related to antenna characteristics in the mobile terminal device of the third embodiment. (A) Rear view and (B) Right side perspective view schematically showing a configuration related to antenna characteristics in a portable terminal device of a comparative example Graph showing efficiency when power is supplied to antenna elements 37, 31, and 31A of the comparative example, the first embodiment, and the second embodiment Graph showing the efficiency of the hemisphere when power is supplied to the antenna elements 37, 31, and 31A of the comparative example, the first embodiment, and the second embodiment The graph which shows the directivity of the XZ plane in the free space at the time of feeding the antenna element 37 of a comparative example The graph which shows the directivity of the YZ plane in the free space at the time of feeding the antenna element 37 of a comparative example The graph which shows the directivity of the XZ plane in the free space at the time of feeding the antenna element 31 of Embodiment 1 The graph which shows the directivity of the YZ plane in the free space at the time of feeding the antenna element 31 of Embodiment 1 The graph which shows the directivity of the XZ plane in the free space at the time of feeding the antenna element 31A of Embodiment 2 The graph which shows the directivity of the YZ plane in the free space at the time of feeding the antenna element 31A of Embodiment 2 The graph which shows the directivity of the XZ plane at the time of hand holding | maintenance at the time of feeding the antenna element 37 of a comparative example The graph which shows the directivity of the YZ plane at the time of hand holding | maintenance at the time of feeding the antenna element 37 of a comparative example The graph which shows the directivity of the XZ plane at the time of hand holding | maintenance at the time of feeding the antenna element 31 of Embodiment 1 The graph which shows the directivity of the YZ plane at the time of hand holding | maintenance at the time of feeding the antenna element 31 of Embodiment 1 The graph which shows the directivity of the XZ plane at the time of hand holding | maintenance at the time of feeding the antenna element 31A of Embodiment 2 The graph which shows the directivity of the YZ plane at the time of hand holding | maintenance at the time of feeding the antenna element 31A of Embodiment 2 (A) Rear view and (B) Right side perspective view schematically showing a configuration related to antenna characteristics in the mobile terminal device of the fourth embodiment. The graph which shows the directivity of the XZ plane in the free space at the time of feeding the antenna element 31 of Embodiment 4 The graph which shows the directivity of the YZ plane in the free space at the time of feeding the antenna element 31 of Embodiment 4 The graph which shows the directivity of the XZ plane at the time of hand holding | maintenance at the time of feeding the antenna element 31 of Embodiment 4 The graph which shows the directivity of the YZ plane at the time of hand holding | maintenance at the time of feeding the antenna element 31 of Embodiment 4 It is an external view which shows an example of the portable terminal device which concerns on Embodiment 5, (A) is a left perspective view of a portable terminal device, (B) is a right perspective view of a portable terminal device. The figure which shows the structural example of the portable terminal device which concerns on Embodiment 5 typically. The figure which shows an example of the circuit board connected to the metal chassis which concerns on Embodiment 5. The figure which shows an example by which the portable terminal device is hold | gripped by the user which concerns on Embodiment 5 It is a figure which shows an example of the metal frame arrange | positioned outside the housing | casing of the portable terminal device which concerns on Embodiment 5, (A) is a left perspective view of a portable terminal device, (B) is a right perspective view of a portable terminal device. It is a figure which shows typically the structural example of the portable terminal device which concerns on Embodiment 6, (A) shows the example of arrangement | positioning of two capacitive coupling sheet metals, (B) shows the example of arrangement | positioning of one capacitive coupling sheet metal. Figure The figure which shows the structural example of the portable terminal device which concerns on Embodiment 7 typically.

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

(Embodiment 1)
[Description of structure]
FIG. 1 is an exploded perspective view showing the entire portable terminal device according to the first embodiment of the present invention. 2A is a plan view showing an upper end surface of the housing, FIG. 2B is a plan view showing a rear surface of the housing, and FIG. 2C is a plan view showing a lower end surface of the housing. 2A to 2C, the antenna elements 30 to 33 are shown with hatching.

  The mobile terminal device according to the first embodiment is a thin box-type terminal device having a display screen arranged on the front surface. As shown in FIG. 1, the portable terminal device includes a housing 22, a circuit board 20, a display unit 10, a sheet metal member 16, an exterior cover 24, left and right metal members (corresponding to conductive members) 12, and upper and lower termination members 14. And four antenna elements 30 to 33 (see FIGS. 2A to 2C).

  The display unit 10 is a thin plate-like unit in which a display layer such as liquid crystal, a backlight layer, a display drive circuit, and the like are provided on the back of the front panel. The display unit 10 is fixed to the housing 22 so as to close the front opening of the housing 22.

  The sheet metal member 16 is a flat plate member mainly made of metal, and is disposed along the back side of the display unit 10 to protect the back side of the display unit 10. Further, the sheet metal member 16 is engaged and fixed to the side wall of the housing 22 to improve the rigidity of the apparatus. Further, the sheet metal member 16 is physically and electrically connected to the ground of the circuit board 20 and becomes the ground of the apparatus.

  The circuit board 20 is configured, for example, by mounting or connecting a communication processing circuit, a display processing circuit, an arithmetic processing circuit, and other various processing devices (such as a camera) on a multilayer printed board. A planar conductive layer serving as a ground is formed in the circuit board 20.

  The casing 22 is a so-called bathtub type in which one wide surface of a thin box (a box having a roundness) is opened, and is made of resin. The housing 22 is also provided with an opening 22H in a half range of the back surface 22B so that the battery pack can be attached and detached from the back of the apparatus (lower side in FIG. 1).

  The exterior cover 24 is a cover that covers the back surface 22B of the housing 22 including the opening 22H of the back surface 22B of the housing 22, and is made of resin. The exterior cover 24 also functions as a battery cover that is attached and detached when the battery pack is replaced.

  The metal member 12 is fixed to the side surfaces along the longitudinal direction of the casing 22 and the display unit 10 so that the casing 22 and the display unit 10 are not bent when a force for bending the casing 22 is applied. Reinforce these. In the first embodiment, the two metal members 12 are fixed to both side surfaces of the casing 22 and exposed to the outside of the apparatus. The metal member 12 has a long shape on one side, and is bent to the front side and the back side at a fold along the longitudinal direction to maintain strength. The metal member 12 can also be called a metal frame or a metal rail.

  FIG. 3 is a schematic view showing a cross section of the side portion of the housing in which the metal member is assembled. FIG. 4 is a side view showing the housing in which the metal member is assembled.

  As shown in FIG. 3, the metal member 12 has a C-shaped portion with a square edge in a cross section perpendicular to the longitudinal direction. A side portion of the housing 22 has a shape portion that is inserted into a C-shaped portion of the metal member 12 and does not fall out. When the apparatus is assembled, the metal member 12 has an upper end or a lower end of the housing 22. It slides from the side and is assembled by engaging with the side portion of the housing 22.

  As shown in FIG. 4, the metal member 12 has a length that extends from substantially the upper end to the lower end of the housing 22, and is disposed with a slight gap S <b> 1 at the upper end and the lower end of the housing 22.

  The termination members 14 and 14 (see FIG. 1) are exterior members that respectively cover the upper end surface 22A and the lower end surface 22C of the housing 22, and are made of resin. Termination member 14 is not limited to resin, and may be composed of a non-conductive and non-magnetic member such as rubber or wood.

  The end member 14 plays a role as a stopper that holds down one end of the metal member 12 in the longitudinal direction and stops the sliding movement of the metal member 12. The end member 14 is fitted to the housing 22 at the gap S1 between the upper and lower ends of the metal member 12 shown in FIG.

  In order to connect the metal member 12 to the ground of the apparatus via a reactance (not shown), the overhanging portion 12 a is fixed to the sheet metal member 16 and the housing 22. The metal member 12 is completely fixed by restraining one end and the other end. The two termination members 14 can also be referred to as an upper cap and a lower cap, respectively.

  As shown in FIG. 2, the antenna elements 30 to 33 are formed by printing a conductor on the outer surface of the housing 22. The antenna elements 30 to 33 include, for example, antenna elements for applications (GPS (Global Positioning System), wireless LAN, short-range wireless communication), antenna elements for sub cellular communication, and 2 for main cellular communication. Two antenna elements corresponding to one band are included.

  Each of the antenna elements 30 to 33 is formed across the back surface 22B and the upper end surface 22A of the housing 22 or the back surface 22B and the lower end surface 22C of the housing 22. Since the back surface 22B of the housing 22 is exposed to the outside when the battery cover is removed, a protective film 39 that covers the printed surfaces of the antenna elements 30 to 33 is formed on the back surface 22B of the housing 22.

  FIG. 5 is a diagram for explaining an electrical connection configuration between the antenna element printed on the housing and the circuit board.

  As shown in FIG. 5, the upper two antenna elements 30 and 31 are provided with conductors d and d connected to the circuit board 20 at one end on the back surface 22 </ b> B side of the housing 22. The conductors d and d are embedded in the wall of the housing 22 so as to communicate with the front and back of the back surface 22B of the housing 22. Via these conductors d and d, the antenna elements 30 and 31 printed on the outer surface of the housing 22 and the power feeding parts f and f of the circuit board 20 are electrically connected through, for example, spring contacts or the like. The

  A wireless circuit having a power amplifier that outputs a transmission signal, a reception amplifier that inputs a reception signal (only a reception amplifier in the case of reception only), and the like are mounted in the vicinity of the power supply units f and f of the circuit board 20. A signal line of a wireless circuit having a power amplifier and a reception amplifier is connected to the power supply units f and f, and the ground of the wireless circuit is grounded to the ground of the circuit board 20. The feeding parts f and f are connection points for transmitting high-frequency power from the radio circuit to the antenna elements 30 and 31, or connection points for transmitting high-frequency power generated by the radio waves captured by the antenna elements 30 and 31 to the radio circuit. It is.

  The lower two antenna elements 32, 33 are provided with conductors d, d that communicate with the front and back of the back surface 22 </ b> B of the housing 22 at one end on the back surface 22 </ b> B side of the housing 22. The conductors d and d are embedded in the wall of the housing 22 and electrically connect the antenna elements 32 and 33 printed on the outer surface of the housing 22 and the circuit inside the housing 22.

  The conductors d and d of the antenna elements 32 and 33 may be directly connected to the power feeding portion of the circuit board 20, similarly to the connection of the upper antenna elements 30 and 31. Alternatively, the conductors d and d of the antenna elements 32 and 33 may be electrically connected to another antenna element accommodated in the housing 22 through a spring contact or the like.

[Structural effects]
In general, the characteristics of an antenna element are affected by surrounding conductors. Since the circuit board 20 and the ground spreading in a planar shape occupy the center of the housing 22, it is desirable to provide the antenna element around the housing 22.

  However, in the first embodiment, the metal member 12 occupies from one end to the other end in the longitudinal direction of the side surface of the housing 22, and therefore when the antenna element is formed near the side surface of the housing 22, the metal member 12. This affects the performance of the antenna element.

  Further, when the antenna element is provided on the outer surface of the housing 22 by printing, it is desirable that the printed matter that becomes the antenna element is provided across two different directions in order to improve the characteristics of the antenna element. Also, printed antenna elements may deteriorate due to rubbing if exposed to the outside.

  Therefore, in the first embodiment, the antenna elements 30 to 33 are formed across the upper end surface 22A and the back surface 22B of the housing 22 or the lower end surface 22C and the back surface 22B of the housing 22.

  Further, the upper end surface 22A and the lower end surface 22C are configured to be covered with the resinous termination member 14 and not exposed to the outside.

  Further, the back surface 22B of the housing 22 is covered with an exterior cover 24, and is configured not to be exposed to the outside during normal use.

  As described above, according to the mobile terminal device of the first embodiment, the strength of the device can be maintained by the metal member 12 even if the device is thinned and the display unit 10 is narrowed. Further, the metal member 12 is connected to the ground through the reactance, so that the deterioration of the antenna characteristics can be avoided. Further, since the antenna elements 30 to 33 are covered with the termination member 14, even if the antenna elements 30 to 33 are formed of printed matter, deterioration due to rubbing or the like is avoided.

[Electric configuration and characteristics of antenna elements]
Next, the electrical configuration and characteristics of the antenna elements 30 and 31 in the first embodiment will be described.

  6A is a rear view and FIG. 6B is a right side perspective view schematically showing a configuration related to antenna characteristics in the mobile terminal device of the first embodiment. FIG. 7 is an exploded perspective view schematically showing a configuration relating to antenna characteristics in the mobile terminal device of the first embodiment. FIG. 8 is a top view schematically showing a configuration related to antenna characteristics in the mobile terminal device of the first embodiment.

[Configuration 1 (Grounding structure of metal member 12)]
The metal member 12 has an overhang portion 12a near the upper end connected to the ground. That is, the metal member 12 is directly connected to the ground spread in a planar shape at this connection point and is grounded. In the specific example of FIG. 1, the metal member 12 is directly connected to the sheet metal member 16 shared with the ground of the circuit board 20, but may be configured to be directly connected to the ground of the circuit board 20. Good. In addition, the metal member 12 may be connected to the ground via a reactance at this connection point. With this configuration, the reactance value can be adjusted, the current flowing from the circuit board 20 to the metal member 12 can be changed, and antenna efficiency can be improved and directivity can be optimized.

In the first embodiment, the connection points of the two metal members 12 to the ground are arranged in the vicinity of the feeding portions of the two antenna elements 30 and 31, respectively. Here, the vicinity of the ₀ wavelength of the transmission and reception signals lambda at a desired frequency, for example, 0.1 × lambda ₀ following distance, more preferably a distance of 0.08 × lambda ₀ or less. This distance is a distance that the high-frequency current of the power feeding unit is transmitted to the metal member 12 through the ground.

  In other words, the two metal members 12 are grounded in the vicinity of the end in the longitudinal direction of the ground spreading in a planar shape and on the same side as the feeding portion of the antennas 30 and 31 (FIG. 6A, FIG. 6 (B)).

[Configuration 2 (Combination configuration of two antenna elements)]
The two antenna elements 30 and 31 are arranged such that each power feeding portion is closer to the metal member 12 than the center of the housing 22 in the left-right direction (Y direction) of the apparatus. On the other hand, the open ends of the antenna elements 30 and 31 are arranged close to and opposed to each other near the center of the device in the Y direction. In other words, the two power feeding units are largely separated in the left-right direction (Y direction) of the apparatus, while the open ends of both are close to each other and face each other.

  Here, the proximity refers to the case where both of the two antenna elements 30 and 31 are arranged, and either the antenna element 30 or the antenna element 31 is fed, or only one of the antenna elements is arranged. The distance at which the antenna efficiency and the directivity change compared to the case where power is supplied. In addition, when a conductor is disposed in the vicinity of both open ends, the influence of the two antenna elements further increases due to capacitive coupling with the conductor. Further, by making the operating frequencies of the two antenna elements 30 and 31 substantially the same, the influence of the two antenna elements further increases.

  In the first embodiment, a conductor 40 that is close to the open ends of both of the two antenna elements 30 and 31 is provided. The conductor 40 is a receiver for audio output, although not particularly limited. The conductor 40 (receiver) is electrically connected to the circuit board 20 via an FPC 41 having reactance (not shown), and inputs a signal with a small resistance in the frequency band of the audio signal, while in a desired radio frequency band. The circuit board 20 is connected to the circuit board 20 with a predetermined reactance. In accordance with this reactance value, the phase of the current flowing from the two antenna elements 30 and 31 to the ground of the circuit board 20 via the conductor 40 and the FPC 41 is changed, and the two antenna elements 30 and 31 and the conductor 40 Can be optimized.

  FIG. 9A is a view of the arrangement relationship between the antenna element and the conductor as viewed from above. FIG. 9B is a view of the arrangement relationship between the antenna element and the conductor as viewed from the rear.

  The conductor 40 has a configuration having a metal part and a resin part. Since the metal surface of the conductor 40 and the antenna elements 30 and 31 are disposed close to each other, the two are capacitively coupled. Furthermore, the degree of capacitive coupling can be increased by disposing a resin portion having a dielectric constant between the two.

In the first embodiment, as shown in FIGS. 9A and 9B, a part of the antenna elements 30 and 31 on the upper end surface 22A side (shaded part in FIG. 9A) and a part on the back surface 22B side (shaded part in FIG. 9B). Part) is close to and faces the metal surface of the conductor 40, and a capacitance is formed between them. With this configuration, for example, when the binding capacity of the size of 0.2PF～0.3PF, the distance between the antenna element 30 and the antenna element 31 can be easily spaced create such 0.021Ramuda ₀ .

  One antenna element 31 is designed with an antenna element length and provided with a matching circuit so as to operate in a 1.5 GHz band of 1.575 GHz to 1.606 GHz used in GPS, for example. The other antenna element 30 is, for example, an 800 MHz band of 875 to 890 MHz, a 1.5 GHz band of 1.496 to 1.515 GHz, and 2.134 to 2 used in a reception band of LTE (Long Term Evolution). The antenna element length is designed so as to operate in the 2 GHz band of 147 GHz, and a matching circuit is provided. Here, the antenna element 31 and the antenna element 30 are both designed to operate in the 1.5 GHz band, and the frequency difference is very close to only 60 MHz, so that they are easily affected by each other. Therefore, when the open ends of both are appropriately capacitively coupled, a current due to excitation of one of the antenna elements 30 and 31 can flow to the other via the coupling capacitance. That is, when the antenna element 31 is excited, a current flows through the circuit board 20 through the antenna element 30 and the matching circuit of the antenna element 30 via the capacitive coupling. From this, it is possible to change the current phase of the antenna element 30 according to the reactance value of the matching circuit of the antenna element 30, and to optimize the coupling state of the antenna element 31 and the antenna element 30.

[Configuration 3 (symmetric configuration of antenna element and metal member 12)]
The two antenna elements 30 and 31 are formed in a direction extending in the vertical direction (Z direction) of the casing 22 from the power feeding unit to the middle panel, and from the middle panel to the vicinity of the open end in the horizontal direction (Y The vicinity of the open end is formed in a direction extending in the front-rear direction (X direction) of the housing 22. In addition, you may form in the direction extended to a Y direction to an open end.

  On the other hand, the two metal members 12 are arranged in the direction extending in the vertical direction (Z direction) of the housing 22, and the direction of the range from the middle of the antenna elements 30 and 31 to the vicinity of the open end, The longitudinal direction is substantially orthogonal.

  Further, the open ends of the two antenna elements 30 and 31 are disposed near the center in the left-right direction of the housing 22 and at the upper end of the housing 22, and the open end of the metal member 12 is the left-right direction of the housing 22. And on the lower side of the housing 22. That is, they are arranged at a large distance.

  Further, the two metal members 12 have substantially symmetrical shapes and symmetrical arrangements with respect to the dividing plane that divides the left and right sides of the apparatus into two.

  Further, the two antenna elements 30 and 31 are arranged so that the power feeding portions are substantially symmetrical with respect to the above-described dividing surface. Further, the two antenna elements 30 and 31 are formed in a symmetric direction with respect to the dividing plane.

  Each of the configurations 1 to 3 contributes to reducing the deterioration of the antenna characteristics caused by the metal member 12 and improving the disturbance of the directivity of the antenna characteristics due to the human body contacting the metal member 12. To do. Moreover, these effects can be comprehensively improved by providing all of the configurations 1 to 3. Details of the antenna characteristics of the first embodiment will be described later with reference to a comparative example.

(Embodiment 2)
10A is a rear view and FIG. 10B is a right side perspective view schematically showing a configuration related to antenna characteristics in the mobile terminal device of the second embodiment.

The mobile terminal device according to the second embodiment is obtained by reversing the direction from the middle of one antenna element 31A to the vicinity of the open end of the two antenna elements 30, 31A, and changing the arrangement of the open end. That is, the open end side from the middle of one antenna element 31A is formed to extend outward in the left-right direction of the apparatus. Spacing between antenna elements 30 and the antenna element 31A are spaced at large distances compared eg 0.1084λ _0, in the first embodiment. Other configurations are the same as those in the first embodiment.

  Compared with the first embodiment, the portable terminal device according to the second embodiment has no capacitive coupling configuration between the two antenna elements 30 and 31A, and the symmetrical configuration of the antenna elements 30 and 31A and the metal member 12 is partly. Asymmetric.

  The antenna characteristics of the second embodiment will also be described in detail later with a comparative example.

(Embodiment 3)
11A is a rear view and FIG. 11B is a left side perspective view schematically showing a configuration related to antenna characteristics in the mobile terminal device of the third embodiment.

  The mobile terminal device according to the third embodiment has a configuration in which the metal member 12 fixed to the side surface of the casing 22 is only on one side, and the other configurations are the same as those in the first embodiment.

  In the portable terminal device according to the third embodiment, the influence of the metal member 12 is produced on only one side of the two antenna elements 30 and 31. For this reason, the characteristic of one antenna element 31 provided in the vicinity of the metal member 12 is the same as that of the first embodiment, and the characteristic of the other antenna element 30 is the characteristic of the antenna element when the metal member 12 is not provided. It is thought that it approaches.

(Antenna characteristics of the first and second embodiments)
Hereinafter, the antenna characteristics of the first embodiment and the second embodiment will be described in detail along with comparative examples.

  FIG. 12A is a rear view and FIG. 12B is a right side perspective view schematically showing a configuration related to antenna characteristics in the portable terminal device of the comparative example.

Compared with Embodiment 1, the portable terminal device of the comparative example has a configuration in which the metal members 12 on both sides of the housing 22 are eliminated and the open ends of the two antenna elements 36 and 37 are not separated from each other. Is. The antenna element 36 is deployed only in the Z-axis direction and is designed to operate in the 1.5 GHz band of 1.575 to 1.606 GHz used in GPS. Further, the antenna element 37 is developed in the Z-axis direction and the Y-axis direction, and is designed to operate only in the 2.GHz to 2.147 GHz 2 GHz band used in the LTE (Long Term Evolution) reception band. . Distance of the open end of the antenna element 36 and the antenna element 37 are spaced apart by a large distance as compared to the example 0.2444Ramuda ₀ the first and second embodiments and the like. In this specification, development can be rephrased as extension.

[Radiation efficiency and hemispherical radiation efficiency]
FIG. 13A is a graph illustrating the efficiency when power is supplied to the antenna elements 37, 31, and 31A of the comparative example, the first embodiment, and the second embodiment. FIG. 13B is a graph showing hemispheric efficiency when power is supplied to antenna elements 37, 31, and 31A according to the comparative example, the first embodiment, and the second embodiment.

  FIG. 13A shows the overall radiation efficiency in all directions, and FIG. 13B shows the radiation efficiency in the hemispherical range in the zenith direction (vertical direction of the casing (Z direction)). 13A and 13B, the horizontal line graph indicates the radiation efficiency in a free space without a shield, and the vertical line pattern graph indicates the radiation efficiency when held with the right hand.

  As shown in FIG. 13A, in the comparative example, the efficiency is greatly deteriorated by hand holding, whereas in Embodiment 2, the efficiency deterioration is halved by hand holding, and in Embodiment 1, the efficiency deterioration by hand holding is large. Reduced.

  From the comparison of the above three forms, the effect of reducing the efficiency deterioration due to the hand-holding is that the metal member 12 and its ground structure, the coupling configuration of the two antenna elements 30 and the antenna elements 31, 31A, and the two antenna elements It is considered that the operating frequency greatly contributes. That is, in the comparative example, the metal member 12 does not exist and the open ends of the two antenna elements 30 and 37 are separated from each other, and the difference in operating frequency is as large as about 500 MHz. Since the member 12 is arranged so as to be grounded in the vicinity of the antenna element 30, 31 or 31A and the difference in operating frequency is as small as 50 MHz, the amount of deterioration of the hand holding state is reduced. In the second embodiment, the open ends of the two antenna elements 30 and 31A are not opposed to each other but are separated from each other. In the first embodiment, the open ends of the two antenna elements 30 and 31 are opposed to each other. And since it is close, the amount of deterioration of the hand holding state is further reduced.

  As shown in FIG. 13B, in the comparative example, the directivity in the zenith direction is deteriorated by hand holding, whereas in the first embodiment, the directivity in the zenith direction is improved by hand holding. That is, in the first embodiment, the radiation efficiency as a whole is slightly reduced by holding the hand, but the radiation efficiency in the zenith direction is improved by changing the directivity to a desired direction. The directivity in the zenith direction is effective for a GPS signal receiving antenna, for example.

  From the comparison of the above three forms, the improvement effect of directivity by hand holding is that the metal member 12 and its ground structure, the coupling configuration of the two antenna elements 30 and 31, and the antenna element 30 and antenna element It is considered that the symmetrical configuration of 31 and the metal member 12 and the operating frequency of the antenna element greatly contribute. That is, in the comparative example, the metal member 12 does not exist, the open end of the antenna element is separated, and the difference in operating frequency of the antenna element is as large as about 500 MHz, whereas in the first embodiment, the metal member 12 is the antenna. The antenna elements 30 and 31 are arranged so as to be grounded, and the open ends of the antenna elements 30 and 31 are opposed and close to each other, and the difference in operating frequency between the antenna elements is as small as 50 MHz. Radiation is improving.

[Directivity in free space]
[Characteristics of Comparative Example]
FIG. 14A is a graph showing the directivity of the XZ plane in free space when the antenna element 37 of the comparative example is fed. FIG. 14B is a graph showing the directivity of the YZ plane in free space when the antenna element 37 of the comparative example is fed. 14A to 19B, black circle plot lines indicate radiation in which the electric field component faces the circumferential direction of the plane (referred to as Eθ component), and rhombus plot lines indicate radiation in which the electric field component faces in the orthogonal direction of the plane (Eφ component). Called).

  In the comparative example, in the XZ plane of FIG. 14A, the total radiation amount is equal between the Eθ component and the Eφ component. Further, since both the Eθ component and the Eφ component have a radiation amount in the −Z direction larger than that in the + Z direction, they occupy the middle of the device rather than the antenna element 37 disposed at the upper end of the device. It is considered that currents directed in the Y direction and Z direction of the ground contribute to radiation.

  In the comparative example, in the YZ plane of FIG. 14B, radiation in the Y direction (θ = −90 ° to 90 ° (270 ° to 360 °, 0 ° to 90 °)) and −Y direction (θ = The symmetry with respect to the Z axis with respect to the radiation of 90 ° to 270 ° is reduced. This is presumably because the current of the circuit board 20 is concentrated at one end on the power supply unit side and flows asymmetrically with respect to the Z axis because the power supply unit of the antenna element 37 is arranged at the corner.

  From the characteristics of FIGS. 14A and 14B, it is considered that the ratio of the current flowing through the circuit board 20 developed in the Y direction and the Z direction contributes to radiation is high in the device of the comparative example.

[Characteristics of Embodiment 1]
FIG. 15A is a graph showing the directivity of the XZ plane in free space when the antenna element 31 of the first embodiment is fed. FIG. 15B is a graph showing the directivity of the YZ plane in free space when the antenna element 31 of Embodiment 1 is fed.

  In the first embodiment, the radiation of the Eφ component is generally larger in the XZ plane of FIG. 15A than the radiation of the Eθ component. This is considered that the current in the Y-axis direction contributes to radiation rather than the Z-axis direction. As described later, the same tendency is found in the second embodiment, but this tendency is stronger in the first embodiment. Compared with the comparative example, since the emission of the Eθ component is extremely reduced, it is considered that the ground current developed in the Z-axis direction is reduced. The radiation of the Eφ component is almost symmetric with respect to the Z axis.

  In the first embodiment, the radiation of the Eθ component is substantially symmetrical with respect to the Y axis and the Z axis in the YZ plane of FIG. 15B.

  From these characteristics shown in FIGS. 15A and 15B, in the first embodiment, symmetrical radiation is performed with respect to each axis of XYZ, and characteristics that are almost uniform and omnidirectional in any direction are obtained. I understand.

[Characteristics of Embodiment 2]
FIG. 16A is a graph showing the directivity of the XZ plane in free space when the antenna element 31A of the second embodiment is fed. FIG. 16B is a graph showing the directivity of the YZ plane in free space when the antenna element 31A of Embodiment 2 is fed.

  In the second embodiment, the Eφ component radiation is generally larger than the Eθ component radiation in the XZ plane of FIG. 16A. Further, the Eθ component is small as compared with the comparative example, but is large as compared with the first embodiment. This is considered to depend on the fact that the current developed in the Z-axis direction is smaller than that in the comparative example and larger than that in the first embodiment.

  In the second embodiment, in the YZ plane of FIG. 16B, the Eθ component is emitted more in the + Z direction than in the −Z direction. Further, the radiation of the Eθ component has an angular width of 180 ° in the range of θ = −90 ° to 90 ° and an angular width of 180 ° in the range of θ = 90 ° to 270 ° on the Y axis as compared with the comparative example. It is approaching symmetrically. However, as compared with the comparative example, the symmetry with respect to the Y axis is slightly broken in the range of the angle width of 90 ° from θ = 180 ° to 270 ° and the range of the angle width of 90 ° from θ = 270 ° to 360 °. .

  From these characteristics shown in FIGS. 16A and 16B, in the second embodiment, the directivity in the hemispherical surface in the −Y direction of the YZ plane is broken from left-right symmetry, but the directivity in the hemispherical surface in the + Y direction is It can be seen that it is almost symmetrical. This characteristic is considered to be because the two antenna elements 30, 31A do not have a configuration facing each other.

  From the characteristics of FIGS. 14A, 14B, 15A, 15B, 16A, and 16B, and a comparison of the above three forms, the difference in the Eθ component on the XZ plane is the metal member 12 and its grounding structure, and It is considered that the coupling configuration of the two antenna elements 30 and the antenna elements 31 and 31A and the operating frequency of the two antenna elements greatly contribute. That is, in the comparative example, the metal member 12 does not exist, the open end of the antenna element is separated, and the difference between the operating frequencies of the two antenna elements is as large as about 500 MHz. On the other hand, in Embodiments 1 and 2, the metal member 12 is disposed so as to be grounded in the vicinity of the antenna elements 30 and 31, and the difference in operating frequency between the two antenna elements is as small as 50 MHz. As a result, the ground current flowing through the circuit board 20 developed in the Z-axis direction decreases, and the Eθ component decreases. In the second embodiment, the open ends of the antenna elements 30 and 31A do not face each other and are spaced apart. On the other hand, in the first embodiment, since the open ends of the antenna elements 30 and 31 are opposed and close to each other, the ground current flowing through the circuit board 20 developed in the Z-axis direction is further reduced. It is thought that the Eθ component decreases.

[Directivity when holding hands]
[Characteristics of Comparative Example]
FIG. 17A is a graph showing the directivity of the XZ plane during hand holding when feeding the antenna element 37 of the comparative example. FIG. 17B is a graph showing the directivity of the YZ plane during hand holding when the antenna element 37 of the comparative example is fed.

  In the comparative example, as can be seen from FIGS. 17A and 17B, in particular, in the XZ plane of FIG. 17A, the directivity of radiation is greatly disturbed in both the Eθ component and the Eφ component compared to the free space.

  This is thought to be because the ground is covered with a hand and the ground current flowing through the circuit board 20 is inhibited, so that the influence of the hand greatly affects the radiation and the directivity is disturbed.

[Characteristics of Embodiment 1]
FIG. 18A is a graph showing the directivity of the XZ plane during hand holding when the antenna element 31 of the first embodiment is fed. FIG. 18B is a graph showing the directivity of the YZ plane during hand holding when the antenna element 31 according to Embodiment 1 is fed.

  In the first embodiment, in the XZ plane, compared to the comparative example, even when the hand is held, the Eθ component is less emitted and the Eφ component is emitted more. Further, the radiation of the Eφ component changes greatly in directivity as compared to a free space without shielding, and the zenith directions θ = 315 ° to 0 °, 0 ° to 135 ° (when holding the mobile terminal device) = −45 ° to 135 °) is large.

  This is because the ground current of the circuit board 20 flows dispersedly in the metal member 12, and further, when the hand contacts the metal member 12, the current flowing in the metal member 12 is dispersed in the two antenna elements 30, 31. This is probably because the directivity has changed.

[Characteristics of Embodiment 2]
FIG. 19A is a graph showing the directivity on the XZ plane during hand-holding when power is supplied to the antenna element 31A of the second embodiment. FIG. 19B is a graph showing the directivity of the YZ plane during hand-holding when power is supplied to antenna element 31A of the second embodiment.

  In the second embodiment, in the XZ plane, the radiation of the Eθ component is larger than that in the first embodiment, and the radiation of the Eφ component is also uniform at all angles.

  This is considered because one antenna element 31A is short in the Y direction, the direction in the Y direction does not face the antenna element 30A, and the open ends of the two antenna elements 30, 31A are not close to each other. That is, in the second embodiment, this configuration reduces the current in the Y direction of the antenna element 31A and increases the ground current of the circuit board 20 developed in the Z-axis direction as compared with the first embodiment. Therefore, the ground current flowing through the metal member 12 is smaller than that in the first embodiment. Therefore, even if the hand contacts the metal member 12, there is less current distribution from the metal member 12 to the antenna element, and X It is considered that the directivity of the Eφ component in the −Z plane does not have much influence.

  Further, in the second embodiment, since the ground current flowing through the circuit board 20 is larger than that in the first embodiment, the ground current flowing through the metal member 12 is smaller than that in the first embodiment. For this reason, in the second embodiment, even when the ground and the metal member 12 are covered with hands, there is little dispersion of current from the metal member 12 to the antenna elements 30 and 31A, and the directivity of the Eφ component in the XZ plane It is considered difficult to improve.

[Effects on antenna characteristics]
As described above, in the first to third embodiments of the present invention, the antenna characteristics are deteriorated due to the proximity of the human body to the metal member 12 or the contact of the human body with the metal member 12 and the ground structure of the metal member 12. Reduction can be achieved.

  Furthermore, in the first embodiment of the present invention, the proximity of the open ends of the two antenna elements 30 and 31 and the symmetrical configuration of the antenna elements 30 and 31 and the metal member 12, even when the metal member 12 contacts the hand, are desirable. The effect that the antenna characteristic with the directivity of can be obtained is obtained.

(Embodiment 4)
20A is a rear view and FIG. 20B is a right side perspective view schematically showing a configuration related to antenna characteristics in the mobile terminal device of the fourth embodiment.

  In the mobile terminal device of the fourth embodiment, the ground points G and G of the two metal members 12A are changed from the arrangement of the first embodiment.

  In the fourth embodiment, the metal member 12A is a conductive frame for improving the characteristics of the finger detection function of the non-contact type touch panel. The metal member 12 </ b> A has a length extending from almost one end to the other end in the longitudinal direction of the housing 22, and is fixed to both the left and right sides of the housing 22. The metal member 12 </ b> A is not exposed to the outer surface of the housing 22 and is disposed inside the wall portion of the housing 22. Although the metal member 12A is not in direct contact with the user's hand, the metal member 12A and the user's hand are coupled with each other at a high frequency due to the proximity of the user's hand across the wall of the thin housing 22. The antenna characteristics are affected as in the embodiment.

  Note that the metal member 12A may be configured to be exposed to the outside of the housing 22 in the same manner as the metal member 12 of the other embodiments, and even in this case, the antenna characteristics described below are not significantly changed. . Conversely, the metal members 12 of the other first to third embodiments may also be configured not to be exposed on the outer surface of the housing 22 as in the fourth embodiment. It is considered that the antenna characteristics of No. 3 are not significantly different from those described above.

  As described in the first embodiment, the ground includes a planar conductive layer formed in an intermediate layer of the circuit board 20 and a sheet metal member 16 electrically connected to the conductive layer. The ground has a configuration spreading in a planar shape in the left-right and up-down directions of the device, and the length of the ground in the longitudinal direction is substantially the same as the length of the metal member 12A.

[Arrangement of grounding points for metal members]
As shown in FIGS. 20A and 20B, the ground point G of the metal member 12 </ b> A is close to the end in the longitudinal direction of the ground spreading in a planar shape, and is a region on the opposite side of the feeding portion of the antennas 30 and 31. Is arranged. The ground point G of the left metal member 12A is provided on the left side of the ground. The ground point G of the right metal member 12A is provided on the right side of the ground.

[Antenna characteristics]
[Directivity in free space]
FIG. 21A is a graph showing the directivity of the XZ plane in free space when the antenna element 31 of the fourth embodiment is fed. FIG. 21B is a graph showing the directivity of the YZ plane in free space when the antenna element 31 of the fourth embodiment is fed. In FIG. 21A to FIG. 22B, black circle plot lines indicate radiation in which the electric field component faces the circumferential direction of the plane (referred to as Eθ component), and rhombus plot lines indicate radiation in which the electric field component faces in the orthogonal direction of the plane (Eφ component) Called).

  In the fourth embodiment, in the XZ plane of FIG. 21A, the emission of the Eφ component is generally larger than the emission of the Eθ component. Further, in the fourth embodiment, compared to the second embodiment (FIG. 16A), the emission of the Eθ component is reduced and the emission of the Eφ component in the −Z direction is increased. This is presumably because the current in the Y direction of the ground has increased.

  Further, in the XZ plane of FIG. 21A, the radiation of the Eφ component is substantially line symmetric with respect to the Z axis.

  In the YZ plane of FIG. 21B, the radiation of the Eθ component is substantially line symmetric with respect to the Y axis, and is also substantially line symmetric with respect to the Z axis.

  Overall, the antenna characteristics of the free space in the fourth embodiment are such that the Eφ component in the XZ plane, which occupies most of the radiation, and the Eθ component in the YZ component are line symmetric with respect to the respective axes. It is a characteristic having uniform omnidirectionality in any direction.

[Directivity when holding hands]
FIG. 22A is a graph showing the directivity of the XZ plane during hand holding when the antenna element 31 of the fourth embodiment is fed. FIG. 22B is a graph showing the directivity on the YZ plane during hand holding when the antenna element 31 of the fourth embodiment is fed.

  In the fourth embodiment, in the XZ plane of FIG. 22A, compared to the comparative example (FIG. 17A), the emission of the Eθ component is small and the emission of the Eφ component is large. The directivity of the Eφ component radiation is greatly changed compared to free space (FIG. 16A), the radiation at θ = 315 ° to 0 ° and 0 ° to 100 ° is large, and the radiation in the zenith direction is increased. Here, the zenith direction corresponds to the direction of the zenith when the apparatus is held obliquely so that the front surface of the apparatus faces obliquely upward.

  Further, in the fourth embodiment, the radiation increases in the zenith direction of θ = 45 ° to 135 ° also in the YZ plane of FIG. 22B.

  The antenna characteristic of the fourth embodiment is that the current flowing through the metal members 12A and 12A moves to the antenna elements 30 and 31 when the user's hand is close to the metal members 12A and 12A. Sex is thought to have changed. The directivity facing the zenith direction is effective for a GPS signal receiving antenna, for example.

[Effect of Embodiment 4]
As described above, according to the mobile terminal device of the fourth embodiment, good antenna characteristics can be obtained by the configuration of the antenna elements 30 and 31 and the arrangement of the ground points G and G of the metal members 12A and 12A. it can.

  Moreover, in a smart phone type portable terminal device, a large number of circuits and functional modules are generally mounted in the upper half of the device, and a battery pack housing portion is formed in the lower half of the device. For this reason, generally, it is difficult to secure the space for the grounding points G and G of the metal members 12A and 12A in the upper half region of the apparatus, and it is easy to secure the space for the grounding points G and G in the lower half region of the device. . According to the mobile terminal device of the fourth embodiment, even with such a general configuration, the space between the ground points G and G of the metal members 12A and 12A can be easily secured without deteriorating the antenna characteristics. The effect is obtained.

  The first to fourth embodiments of the present invention have been described above.

  In the first to fourth embodiments described above, the antenna elements 30 to 33 are described as an example of the printed material. However, the antenna element may not be configured of the printed material. Even in this configuration, the above-described effect on the characteristics of the antenna can be obtained similarly. Further, when the antenna element is not formed of a printed material, the termination member 14 may not be provided.

  In the first to fourth embodiments described above, the configuration in which the open ends of the two antenna elements are capacitively coupled with the common conductor 40 has been described as an example, but the two antenna elements are not provided without providing the conductor. A configuration in which the open end of the capacitor is directly capacitively coupled may be employed. Further, the conductor 40 is not limited to a receiver, and a microphone, a speaker, or a conductor dedicated for capacitive coupling may be employed.

(Background and problems according to Embodiments 5 to 7)
In recent years, smart phone type mobile terminal devices are rapidly spreading.
The following patent documents 3-5 are known regarding the technique which arrange | positions an electroconductive member on the outer side of the housing | casing of a portable terminal device.

  Patent Document 3 discloses an antenna pattern frame in which a wire antenna is disposed in a groove provided on the outside of a radiator frame, and a circuit board on the opposite side of the frame is connected to the wire antenna through a through portion formed in the case. .

  Patent Document 4 discloses a portable wireless terminal that reduces a variation width of a VSWR (Voltage Standing Wave Ratio) characteristic with respect to external interference (user's finger touch) by disposing a conductor around an internal antenna. Has been.

  In Patent Document 5, a bezel formed of a conductive material is used to surround a peripheral member disposed on the front surface of a housing or a slot in which a plate-like inverted F antenna element is disposed above, and a display is mounted on the housing. A holding handheld electronic device is disclosed.

[Patent Document 3] Japanese Patent Application Laid-Open No. 2011-172222 [Patent Document 4] Japanese Patent Application Laid-Open No. 2006-148943 [Patent Document 5] Japanese Patent Application Publication No. 2010-53574

  In order to improve the design of the mobile terminal device, for example, it has been studied to apply a coating for giving a metallic texture to the exterior of the housing or to arrange a frame made of the metal itself. Therefore, it is expected that the arrangement of metal objects outside the housing will increase in the future.

  When a metal object is disposed outside the housing, the metal object is disposed in the vicinity of the antenna element or antenna ground housed in the housing. As a result, capacitive coupling occurs between the metal object and the antenna element or between the metal object and the antenna ground, and the antenna current flows to the metal object through this path.

  Since the antenna current concentrates on the antenna ground near the feeding point of the antenna, if capacitive coupling occurs between the metal object and the antenna ground, a large amount of current is drawn from the antenna ground near the feeding point where the antenna current is concentrated. Flowing into.

  In portable terminal devices, an antenna is often provided at the lower end of a housing. In this case, the feeding point of the antenna is also provided at the lower end portion of the housing, and a large amount of current flows through the metal portion on the antenna side, that is, the metal portion near the lower end portion of the housing.

  Therefore, when the user grips the lower part of the casing of the mobile terminal device, the user grips the portion where the antenna current is concentrated, the antenna characteristics deteriorate, and the communication capability of the mobile terminal device decreases.

  The present invention has been made in view of the above circumstances, and provides a portable terminal device capable of maintaining good antenna characteristics even when a conductive member is disposed outside the housing.

(Embodiment 5)
23A and 23B are external views illustrating an example of the mobile terminal device 101 according to Embodiment 5. The mobile terminal device 101 includes a housing 102, metal frames 103a and 103b, and a display unit 104. The portable terminal device 101 can also be called a portable wireless device.

  The housing 102 has, for example, a substantially square shape and is configured by a non-conductive member.

  The metal frames 103a and 103b are examples of conductive members, and are members (decorative metal frames) for decorating the housing 102, for example. At least a part of the metal frames 103 a and 103 b is disposed so as to be exposed to the outside of the housing 102.

  The display unit 104 has a display screen configured by, for example, an LCD (Liquid Crystal Display). The display screen is provided on the front surface of the housing 102, for example.

  FIG. 24 is a diagram illustrating an example of a state in which the housing 102 of the mobile terminal device 101 is removed. The mobile terminal device 101 includes a circuit board 111, a metal chassis 112, an antenna element (antenna) 113, and a feeding point 114 for the antenna element.

  The circuit board 111 is a board having a rectangular shape, for example, which is disposed substantially parallel to the display screen of the display unit 104. For example, a circuit pattern or a ground pattern is formed on the circuit board 111. Although not shown in FIG. 24, a large number of electronic components and the like are mounted on the pattern formed on the circuit board 111.

  The metal chassis 112 is, for example, a chassis (for reinforcement) for securing the strength of the housing 102 and has, for example, a substantially rectangular shape. The metal chassis 112 is configured by a conductive member (for example, stainless steel). The metal chassis 112 is attached to the display unit 104 and has a function of holding the LCD and ensuring the strength of the LCD.

  The metal chassis 112 has a function as a ground (GND) part of the mobile terminal device 101. A circuit board 111 is connected to the metal chassis 112.

  FIG. 25 shows the circuit board 111 connected to the metal chassis 112. The circuit board 111 is disposed so as to overlap the metal chassis 112. The ground pattern of the circuit board 111 is connected at connection points 121 a to 121 d of the metal chassis 112. Thereby, the circuit board 111 and the metal chassis 112 are set to the same potential.

  The metal chassis 112 is provided, for example, to reinforce rigidity, and is not an essential member.

  The antenna element 113 is a cellular antenna, for example, and is connected to the feeding point 114 of the circuit board 111. A wireless circuit 119 is mounted on the circuit board 111, and the antenna element 113 is supplied with power from the wireless circuit 119. The ground of the wireless circuit 119 is connected to the ground pattern of the circuit board 111.

  The metal frames 103a and 103b have, for example, an I shape, and are arranged along the left and right side walls of the housing 102 so as to correspond to the region from the upper end to the lower end of the side wall. The metal frames 103a and 103b are close to and opposed to one side end (left end) or the other side end (right side) of the circuit board 111.

  Since the metal frames 103a and 103b are arranged on the side surfaces of the housing, the metal frames 103a and 103b are arranged at a distance to be capacitively coupled to the circuit board 111 or the metal chassis 112. The distance between the metal frames 103a and 103b and the circuit board 111 or the metal chassis 112 is set to, for example, λ / 20 or less in relation to the low-frequency operating frequency (wavelength λ) covered by the antenna element 113.

  The metal frames 103a and 103b are grounded to the ground pattern of the circuit board 111 at a portion (non-gripping portion) that is not gripped by the user in use. The non-gripping portion refers to a surface area of the housing 102 that is difficult for a user to grip when using the mobile terminal device 101. In FIG. 26, the non-gripping portion is, for example, a region on the upper end portion side of the housing 102 or the housing 102 on the side opposite to the antenna element 113 when the antenna element 113 is disposed on the lower end portion of the housing 102. Region (region on the upper end side).

  FIGS. 27A and 27B are diagrams showing another example of the metal frames 103a and 103b. The metal frames 130a and 130b shown in FIGS. 27A and 27B have, for example, a U shape. For example, the metal frames 130a and 130b pass from the first side end (for example, the left end) of the housing 102 to the second side end (for example, the upper end) adjacent to the first side end. , And is arranged over a third side end portion (for example, a right end portion) that faces the first side end portion.

  The shape of the metal frame may not be I-shaped or U-shaped, for example, L-shaped.

  As described above, the mobile terminal device 101 includes the housing 102, the circuit board 111, the antenna, and the first conductive member. The circuit board 111 is provided on the housing 102. The antenna is provided on the housing 102 and is electrically connected to the circuit board 111. The first conductive member is at least partially exposed from the housing 102, is disposed near one end of the housing 102, and is capacitively coupled to the circuit board 111. Further, the first conductive member is electrically connected to the circuit board 111 at the non-gripping portion. The antenna is, for example, the antenna element 113. The first conductive member is, for example, a metal frame 103b. The vicinity of one end of the housing 102 is, for example, the vicinity of the right end of the housing 102.

  According to the mobile terminal device 101, the antennas that flow to the metal frames 103 a and 103 b through the circuit board 111 and the metal chassis 112 by connecting the metal frames 103 a and 103 b and the circuit board 111 at the non-gripping portion of the housing 102. Most of the current (high-frequency current) can be concentrated in the vicinity of the electrical connection point (for example, broken line regions 117 and 118 in FIG. 24).

  In the example of FIG. 26, an antenna is provided at a portion that is in the vicinity of an electrical contact point between the metal frames 103a and 103b and the circuit board 111, that is, a portion that is difficult to be held by the hand (housing portions of the broken line regions 124 and 125: non-gripping portions). The current can be concentrated. That is, it is possible to prevent the antenna current from being concentrated on a portion of the housing 102 held by the hand (housing portions of the broken line regions 122 and 123: gripping portions).

  As a result, even when the mobile terminal device 101 is provided with a conductive member outside the housing 102, the mobile terminal device 101 can prevent a decrease in high-frequency signal radiation caused by the user holding the mobile terminal device 101, and achieve high antenna performance. It can be secured.

  In the mobile terminal device 101, the first conductor member may be grounded to the ground portion of the metal chassis 112. As a result, the antenna current concentrates on the non-gripping portion, so that it is possible to prevent deterioration of the antenna characteristics due to gripping by the user. Further, since a larger amount of current can be concentrated at the contact portion than when capacitively coupled by grounding, a great characteristic improvement effect can be obtained.

  In the mobile terminal device 101, the antenna 113 is provided at one end portion in the first direction of the housing 102, and the non-gripping portion includes a region corresponding to the other end portion in the first direction of the housing 102. But you can. The first direction is, for example, the vertical direction in FIG. Thereby, since the antenna 113 and the non-gripping portion are formed at the opposite ends, even if the antenna current is concentrated in the vicinity of the antenna 113, it is possible to prevent deterioration of the antenna characteristics due to gripping by the user.

  In the mobile terminal device 101, the first conductive member may be extended along at least a part of the peripheral end portion of the circuit board 111. Thereby, since the freedom degree of arrangement | positioning of a 1st electrically-conductive member increases, the design property of the portable terminal device 101 can be improved.

(Embodiment 6)
FIGS. 28A and 28B are diagrams schematically illustrating a configuration example of the mobile terminal device 101B (101B1, 101B2) according to the sixth embodiment.

  The portable terminal device 101B1 includes capacitive coupling metal plates 142 and 143 for concentrating the antenna current flowing through the metal frames 103a and 103b on the non-gripping portion. Similarly, the mobile terminal device 101B2 includes a capacitive coupling sheet metal 144. In the mobile terminal device 101B, the same or similar parts as those of the mobile terminal device 101 are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIG. 28A, the mobile terminal device 101B1 includes a plurality of capacitive coupling sheet metals (for example, two capacitive coupling sheet metals 142 and 143). The metal frames 103a and 103b are connected to the capacitive coupling metal plates 142 and 143 at the non-gripping portion (see reference numerals 145 and 146 in FIGS. 28A and 28B). An example of the non-gripping portion is shown in FIG.

  The capacitive coupling metal plates 142 and 143 have, for example, a substantially rectangular shape. The capacitive coupling metal plates 142 and 143 are disposed to face each other at both end portions of the circuit board 111, for example. The capacitive coupling metal plates 142 and 143 are disposed inside the housing 102 in the non-gripping portion.

  Further, the capacitive coupling metal plates 142 and 143 are arranged with a predetermined distance (clearance) from the circuit board 111 so as to be capacitively coupled to the circuit board 111. The distance between the capacitive coupling metal plates 142 and 143 and the circuit board 111 is set to, for example, λ / 30 or less in relation to the operating frequency (wavelength λ) of the antenna element 113. Therefore, stronger capacitive coupling occurs between the capacitive coupling metal plates 142 and 143 and the circuit board 111 than between the metal frames 103 a and 103 b and the circuit board 111.

  In consideration of adjusting the degree of capacitive coupling, the area of the capacitive coupling sheet metals 142 and 143 and the distance between the capacitive coupling sheet metals 142 and 143 and the circuit board 111 may be set. Due to capacitive coupling, the metal frames 103a and 103b are electrically connected to the circuit board 111 via capacitive coupling sheet metals 142 and 143. The antenna current of the circuit board 111 flows to the metal frames 103a and 103b through this connection line.

  As shown in FIG. 28B, the mobile terminal device 101B2 includes one capacitive coupling sheet metal 144. The metal frames 103a and 103b are connected to the capacitive coupling sheet metal 144 at the non-gripping portion (see reference numerals 145 and 146 in FIG. 28B). An example of the non-gripping portion is shown in FIG.

  The capacitive coupling sheet metal 144 has a strip shape extending from one side end of the circuit board 111 to the other side end. The capacitive coupling sheet metal 144 is disposed inside the housing 102 of the non-gripping portion.

  The capacitive coupling sheet metal 144 is disposed with a predetermined distance (clearance) from the circuit board 111 so as to be capacitively coupled to the circuit board 111. The distance between the capacitive coupling sheet metal 144 and the circuit board 111 is set to, for example, λ / 20 or less in relation to the operating frequency (wavelength λ) of the antenna element 113. Therefore, stronger capacitive coupling occurs between the capacitive coupling sheet metal 144 and the circuit board 111 than between the metal frames 103 a and 103 b and the circuit board 111.

  In consideration of adjusting the degree of capacitive coupling, the area of the capacitive coupling sheet metal 144 and the distance between the capacitive coupling sheet metal 144 and the circuit board 111 may be set. By the capacitive coupling, the metal frames 103a and 103b are electrically connected to the circuit board 111 via the capacitive coupling sheet metal 144. The antenna current of the circuit board 111 flows to the metal frames 103a and 103b through this connection line.

  As described above, the mobile terminal device 101 </ b> B may include the second conductive member electrically connected to the first conductive member, and the second conductive member may be capacitively coupled to the circuit board 111.

  According to the mobile terminal device 101 </ b> B, the metal frames 103 a and 103 b and the capacitive coupling metal plates 142 to 144 are electrically connected at the non-gripping portion of the housing 102. Further, the connected capacitive coupling metal plates 142 to 144 are arranged on the circuit board 111 with a predetermined clearance, that is, arranged in the casing 102 corresponding to the non-gripping portion of the casing 102. Therefore, the metal frames 103a and 103b and the circuit board 111 can be electrically connected via the capacitive coupling metal plates 142 to 144. Even when it is difficult to physically provide a contact point due to the housing and the internal structure, the electrical connection effect can be obtained by using this method.

  As a result, the mobile terminal device 101B can pass most of the antenna current (high-frequency current) flowing from the circuit board 111 to the metal frames 103a and 103b through this connection line. Then, the mobile terminal device 101B can concentrate the antenna current in the vicinity of the electrical connection point (for example, the broken line areas 149 and 150 in FIG. 28A and the broken line areas 151 and 152 in FIG. 28B).

  In the example of FIG. 26, a portion that is in the vicinity of an electrical contact point between the metal frames 103a and 103b and the capacitive coupling metal plates 142 to 144, that is, a portion that is difficult to be held by the hand (a housing portion of the broken line regions 124 and 125: non-gripping The antenna current can be concentrated on That is, it is possible to prevent the antenna current from being concentrated on a portion of the housing 102 held by the hand (housing portions of the broken line regions 122 and 123: gripping portions).

  Thereby, even when the portable terminal device 101B is provided with a conductive member outside the housing, it is possible to prevent a decrease in radiation of the high-frequency signal caused by the user holding the portable terminal device 101B, and to ensure high antenna performance. .

(Embodiment 7)
FIG. 29 is a diagram schematically illustrating a configuration example of the mobile terminal device 101C according to the seventh embodiment.
The portable terminal device 101C includes two antenna elements 113 and 162 and two cutoff filters 164 and 165. The number of antenna elements and cutoff filters is not limited to this.

  In FIG. 29, only the metal frame 103b on the right side of the circuit board 111 is shown, but the metal frame 103a may be arranged on the left side of the circuit board 111, or may be arranged at another location. In FIG. 29, the cutoff filters 164 and 165 are connected to the metal frame 103b, and the cutoff filters 164 and 165 are grounded to the circuit board 111. Similarly, a cutoff filter may be connected to the metal frame 103 a not shown, and the cutoff filter may be grounded to the circuit board 111. In the following description, the metal frame 103b will be described. However, when the metal frame 103a is provided, the same applies to the metal frame 103a.

  In the portable terminal device 101C, the same or similar parts as those of the portable terminal device 101 are denoted by the same reference numerals and description thereof is omitted.

  The portable terminal device 101 </ b> C includes a first antenna element 113 and a second antenna element 162. The first antenna element 113 is, for example, a cellular antenna element. The second antenna element 162 is, for example, an antenna element for applications (for example, for GPS, W-LAN, One Seg, or Felica (registered trademark)).

  The operating frequency of the first antenna element 113 is frequency f1, the wavelength is λ1, the operating frequency of the second antenna element 162 is frequency f2, and the wavelength is λ2. The first antenna element 113 is disposed on one end side (for example, the lower end side) of the circuit board 111 and is connected to the feeding point 163 of the circuit board 111. The second antenna element 162 is disposed on the other end side (for example, the upper end side) of the circuit board 111 and connected to the feeding point 163 of the circuit board 111. Similarly to the first antenna element 113, the second antenna element 162 is set to the same potential as the circuit board 111 with the ground pattern of the circuit board 111 as the ground.

  The metal frame 103b is disposed corresponding to the region from the substantially upper end to the lower end of the side end portion (for example, the right end portion) of the housing 102 in FIG. The metal frame 103b is located close to and opposed to one end (for example, the right end) of the circuit board 111 or the metal chassis 112, and is disposed at a distance that is capacitively coupled to the circuit board 111. The distance between the metal frame 103b and the circuit board 111 or the metal chassis 112 is set to, for example, (λ1) / 20 or less in relation to the wavelength λ1 corresponding to the frequency f1.

  In addition, the metal frame 103b is disposed at a distance L that is close to and opposed to the second antenna element 162 on the other end side and capacitively coupled to the second antenna element 162. The distance L between the metal frame 103b and the second antenna element 162 is set to, for example, (λ2) / 20 or less in relation to the wavelength λ2 corresponding to the frequency f2. The second antenna element 162 is disposed at the upper right end of the circuit board 111, for example.

  Further, the metal frame 103 b is grounded to the circuit board 111 via the cutoff filter 165 and is grounded to the circuit board 111 via the cutoff filter 164.

  The cutoff filter 164 is a filter that cuts off an electrical signal having a frequency f1, and the cutoff filter 165 is a filter that cuts off an electrical signal having a frequency f2. One end of the cutoff filter 164 is connected to one end (for example, the lower end) of the metal frame 103b, and the other end is connected to a ground formed at one end (for example, the lower end) of the circuit board 111. The cutoff filter 165 has one end connected to the other end (for example, the upper end) of the metal frame 103b and the other end connected to the ground formed at the other end (for example, the upper end) of the circuit board 111. The

  In the circuit board 111, the length of one side (the length in the direction of the metal frame 103b) H of the circuit board 111 is set to, for example, (λ2) / 2 or more in relation to the wavelength λ2 corresponding to the frequency f2. Is done.

  As described above, the mobile terminal device 101C may include the first filter that cuts off the signal at the first frequency and the second filter that cuts off the signal at the second frequency. The first filter is, for example, the cutoff filter 164. The second filter is a cutoff filter 165, for example. In the mobile terminal device 101C, the antenna may include a first antenna that operates at the first frequency and a second antenna that operates at the second frequency. The first antenna is, for example, the first antenna element 113. The second antenna is, for example, the second antenna element 162. In the mobile terminal device 101C, the second antenna may be capacitively coupled to the first conductive member. The first conductive member may be electrically connected to the circuit board 111 via the first filter and the second filter.

  In the mobile terminal device 101 </ b> C, the first conductive member may be grounded to the ground portion of the circuit board 111.

  According to the mobile terminal device 101C, it is possible to suppress the deterioration of antenna characteristics due to capacitive coupling between the first antenna or the second antenna and the first conductive member, and to improve the antenna gain.

  In the mobile terminal device 101C, the first antenna is provided at one end in the third direction of the housing 102, and the second antenna is provided at the other end in the third direction of the housing 102. May be. The first conductive member is grounded to the circuit board 111 via the first filter at one end in the third direction, and is grounded to the circuit board via the second filter at the other end in the third direction. May be. The third direction is, for example, the vertical direction in FIG.

  Thereby, the metal frame 103b and the circuit board 111 can be electrically connected by, for example, grounding the metal frame 103b to the circuit board 111 via the cutoff filter 165. Therefore, the mobile terminal device 101C can flow most of the antenna current (first antenna current) from the first antenna element 113 flowing from the circuit board 111 to the metal frame 103b through this connection line.

  In addition, at the end of the mobile terminal device 101C, for example, the metal frame 103b is grounded to the circuit board 111 via the cutoff filter 164, so that the first antenna current flows from the circuit board 111 to the end of the metal frame 103b. Flow can be suppressed. The end is, for example, the lower end of the mobile terminal device 101C in FIG.

  As a result, the mobile terminal device 101C can concentrate the first antenna current in the vicinity of the electrical connection point (for example, the broken line region 168 in FIG. 29).

  In addition, the mobile terminal device 101C is configured such that the metal frame 103b is placed at the end of the circuit board 111 opposite to the second antenna element 162 (for example, the lower end of the mobile terminal device 101C in FIG. For example, the circuit board 111 is grounded. Thereby, the metal frame 103b and the circuit board 111 can be electrically connected.

  Therefore, the mobile terminal device 101C can concentrate the antenna current (second antenna current) from the second antenna element 162 on the end portion of the circuit board 111 (for example, a broken line region 169 in FIG. 29). Then, most of the second antenna current flowing from the circuit board 111 to the metal frame 103b can be passed through this connection line.

  Thereby, the mobile terminal device 101C can concentrate the antenna current on the end portion of the first conductive member, and can maintain the antenna characteristics favorably. That is, the mobile terminal device 101C can concentrate the first antenna current and the second antenna current in the vicinity of the end portion (for example, the broken line regions 168 and 169 in FIG. 29) where the radiation efficiency to the space of the metal frame 103b is high. Therefore, the second antenna current can be prevented from being concentrated in the central portion (the portion that is difficult to contribute to the radiation of the antenna current) where the radiation efficiency to the space of the metal frame 103b is low, and both antenna characteristics can be maintained well. .

  Further, in the mobile terminal device 101C, the first conductive member has a portion extending along the second direction of the circuit board 111, and the length of the circuit board 111 in the second direction is the second. It may be 1/2 or more of the wavelength corresponding to the frequency. The second direction is, for example, the vertical direction in FIG.

  As a result, the mobile terminal device 101C can prevent deterioration of the antenna radiation efficiency even when the mobile terminal device 101C has a predetermined length or longer, and the high antenna performance of the first antenna and the second antenna can be prevented. It can be secured.

  The present invention is not limited to the configuration of the above-described embodiment, and any configuration can be used as long as the functions shown in the claims or the functions of the configuration of the present embodiment can be achieved. Is also applicable.

  The above embodiments may be combined. Moreover, although the said embodiment demonstrated that a portable terminal device provided a metal frame, you may prepare a metal frame as a different body from a portable terminal device.

  The disclosure contents of the specification, drawings and abstract contained in the Japanese application of Japanese Patent Application No. 2012-110039 filed on May 11, 2012 and the Japanese application of Japanese Patent Application No. 2013-007234 filed on January 18, 2013 are as follows: , All incorporated herein by reference.

  The present invention can be used for mobile phones, smartphones, tablet devices, and the like.

DESCRIPTION OF SYMBOLS 10 Display unit 12, 12A Metal member 14 Termination member 16 Sheet metal member 20 Circuit board 22 Case 22A Upper end surface 22B Rear surface 22C Lower end surface 24 Exterior cover 30, 31, 31A, 32, 33 Antenna element 40 Conductor f Power supply unit 101, 101B, 101B1, 101B2, 101C Mobile terminal device 102 Case 103a, 103b, 130a, 130b Metal frame 104 Display unit 111 Circuit board 112 Metal chassis 113 Antenna element (first antenna element)
114 Feeding point 119 Radio circuit 142, 143, 144 Capacitive coupling sheet metal 162 Second antenna element 163 Feeding point 164 Cutoff filter 165 Cutoff filter

Claims (12)

A portable terminal device,
A housing,
A circuit board housed in the housing;
A ground formed in a planar shape on the circuit board and / or other members in the housing;
A conductive member having a length extending from substantially one end to the other end in the longitudinal direction of the housing, and disposed on a side portion along the longitudinal direction of the housing;
At least one antenna element;
A power feeding unit to which the circuit board and the antenna element are connected;
Comprising
The ground is substantially the same length as the conductive member,
The conductive member is connected to a region near the longitudinal end of the ground,
The antenna element is formed of a printed material on an outer surface including an end surface in a longitudinal direction of the casing,
The printed matter constituting the antenna element is formed with a part connected to the back surface of the housing,
The portable terminal device
A termination member made of resin and covering the end surface;
An exterior member covering a range including the printed matter on the back surface of the housing;
A portable terminal device further provided. The power feeding portion is located at a location facing the back surface of the housing in the circuit board,
The feeding part and the printed matter that is the antenna element are electrically connected via a conductive part penetrating the back surface of the housing.
The mobile terminal device according to claim 1 . The conductive member is assembled by sliding along the longitudinal direction on the side surface of the housing,
The termination member abuts one end of the conductive member to stop sliding of the conductive member;
The mobile terminal device according to claim 1 . A portable terminal device,
A housing,
A circuit board housed in the housing;
A ground formed in a planar shape on the circuit board and / or other members in the housing;
A conductive member having a length extending from substantially one end to the other end in the longitudinal direction of the housing, and disposed on a side portion along the longitudinal direction of the housing;
At least one antenna element;
A power feeding unit to which the circuit board and the antenna element are connected;
Comprising
The ground is substantially the same length as the conductive member,
The conductive member is connected to a region near the longitudinal end of the ground,
The conductive member is a member that reinforces the casing, and is exposed to the outside of the mobile terminal device.
Mobile terminal equipment. Two conductive members are respectively provided on both sides of the housing;
A plurality of printed matter constituting a plurality of the antenna elements are respectively provided on both end surfaces of the casing,
The two termination members cover the both end surfaces, respectively.
The mobile terminal device according to claim 1. A housing,
A circuit board housed in the housing;
A ground formed in a planar shape on the circuit board and / or other members in the housing;
A conductive member having a length extending from substantially one end to the other end in the longitudinal direction of the housing, and disposed on a side portion along the longitudinal direction of the housing;
At least one antenna element;
A power feeding unit to which the circuit board and the antenna element are connected;
Comprising
The ground is substantially the same length as the conductive member,
The conductive member is connected to a region near the longitudinal end of the ground,
further,
A first antenna element and a second antenna element as the antenna element;
A first conductive member and a second conductive member respectively disposed on the two side portions of the housing as the conductive member;
Comprising
The feeding portion of the first antenna element is disposed closer to the first conductive member than the center of the circuit board,
The first conductive member is connected to a side of the ground close to the first conductive member and to a region near the end in the longitudinal direction of the ground,
The feeding portion of the second antenna element is disposed on the side closer to the second conductive portion side than the center of the circuit board,
The second conductive member is connected to a region near the second conductive member of the ground and close to a longitudinal end of the ground,
The open end of the first antenna element and the open end of the second antenna element are opposed and close to each other near the center of the device between the first conductive member and the second conductive member.
Mobile terminal device.

The deployment direction of at least a portion near the open end of the first antenna element and the deployment direction of at least the portion near the open end of the second antenna element, the deployment direction of the first conductive member, and the deployment direction of the second conductive member And are almost orthogonal,
The mobile terminal device according to claim 6 . One conductor disposed close to both the open end of the first antenna element and the open end of the second antenna element;
In addition,
The mobile terminal device according to claim 6 . The first conductive member and the second conductive member are substantially symmetrical in shape and arrangement with respect to a split surface that divides the housing into two parts,
The first antenna element and the second antenna element are formed such that each of the power feeding portions is disposed at a position that is substantially symmetrical with respect to the dividing surface, and is in a direction that is approximately symmetrical with respect to the dividing surface.
The mobile terminal device according to claim 6 . A housing,
A circuit board provided in the housing;
An antenna provided in the housing and electrically connected to the circuit board;
A first conductive member that is at least partially exposed from the housing, is disposed near one end of the housing, and is capacitively coupled to the circuit board;
A first filter that blocks a signal at a first frequency;
A second filter that blocks signals at a second frequency;
With
The first conductive member is electrically connected to the circuit board at a non-gripping portion ,
The antenna includes a first antenna that operates at the first frequency, and a second antenna that operates at the second frequency;
The second antenna is capacitively coupled to the first conductive member;
The first conductive member is a portable terminal device that is electrically connected to the circuit board via the first filter and the second filter . It is a portable terminal device according to claim 10 ,
The first conductive member has a portion extending along a second direction of the circuit board;
The length of the said circuit board in the said 2nd direction is a portable terminal device which is 1/2 or more of the wavelength corresponding to a said 2nd frequency. It is a portable terminal device according to claim 10 ,
The first antenna is provided at one end of the housing in the third direction,
The second antenna is provided at the other end in the third direction of the housing,
The first conductive member is grounded to the circuit board via the first filter at one end in the third direction, and via the second filter at the other end in the third direction. A mobile terminal device grounded to the circuit board.

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