JP4657698B2 - Foldable portable radio - Google Patents

Description

  The present invention relates to a foldable portable wireless device capable of reducing electromagnetic radiation to a human body and ensuring high antenna performance in a call state.

  Since the mobile phone is used in the vicinity of the user's head, the local average SAR (Specific Absorption Rate) of electromagnetic waves absorbed by the human body is defined and maximized in consideration of the influence on the human body. A technique for suppressing the local average SAR to a specified value or less is demanded. Generally, this local average SAR has a corresponding relationship with the current distribution, and it is known that the maximum point of current is concentrated in one place, and the local average SAR increases when the maximum point of current exists in the vicinity of the human body. . In particular, in the vicinity of the feeding point of the antenna, the maximum current point is generally concentrated in one place.

  A conventional technique for reducing the local average SAR is to connect (ground) a conductive metal element having one end open to the ground in the vicinity of the feeding point in an unbalanced feeding antenna, and the element has a length that resonates at a desired frequency. Is set. Further, this element is disposed on the housing surface opposite to the housing surface having the opening of the receiving portion close to the human body. With this configuration, the current from the feeding point flows through the conductive metal element, so that the current flowing through the casing surface adjacent to the human body can be reduced, and the radiation to the human body from there can be reduced. (For example, refer to Patent Document 1).

  In addition, as a technique for diverting the current of the power feeding unit, the shield case of the upper housing having the receiving surface in the folding cellular phone is used as an antenna element (antenna 1), and a flexible cable is connected to the ground substrate of the lower housing via a flexible cable. In the structure for feeding power to the antenna element, a rod antenna (antenna 2) is provided in the feeding portion. In other words, power is supplied to two antennas (antenna 1 and antenna 2) from the same feeding point. With this configuration, since the antenna 2 is provided even if it is covered by the user's hand, the antenna performance is hardly deteriorated and high antenna performance can be secured.

JP 2002-353719 A JP 2002-335180 A

  However, the conventional technology for reducing the local average SAR described above has a problem that the antenna performance is greatly affected by the user's hand because the element is connected to the ground.

  In addition, the conventional technology for shunting the current of the power feeding unit described above requires a mechanism structure that electrically connects the rod antenna and the power feeding unit, and further, since the rod antenna is disposed outside the housing, it is compact. There was a problem that it was difficult to convert.

  The present invention has been made to solve the conventional problems, and in particular, provides a foldable portable wireless device that reduces the local average SAR of the foldable portable wireless device.

  The foldable portable wireless device of the present invention includes a first housing, a second housing, a hinge portion that connects the first housing and the second housing so as to be openable and closable ( a) an antenna element provided in the first housing; (b) a conductive metal hinge element electrically connected to the antenna element and provided in the hinge; and (c) the second element. A dipole antenna configured by a first power feeding unit that feeds power to the conductive metal hinge element from a circuit board provided in a housing; and the conductive metal hinge element and capacitive provided in the circuit board. A planar capacitive coupling element provided at a predetermined interval so as to have a reactance, and one end of the planar capacitive coupling element is electrically connected to the planar capacitive coupling element, and the other end is opened to distribute the current flowing through the dipole antenna. Current spreading element.

  Here, the current dispersive element may be configured to have a length of approximately ¼ with respect to a wavelength of a desired frequency, and the antenna current flowing through the conductive metal hinge element is converted into the planar capacitive coupling. By flowing from the element to the current spreading element, the antenna current concentrated on the hinge portion can be dispersed.

  With this configuration, when the dipole antenna is operated, the antenna current is distributed to the conductive metal hinge element at a desired frequency, thereby reducing the current near the human head, thereby reducing the local average SAR. be able to.

  The current spreading element may be arranged in the width direction of the first casing and the second casing.

  With this configuration, it is possible to improve antenna performance at a desired frequency in a call state.

  Further, a second power feeding unit that feeds power from the circuit board to the current spreading element, and a control unit that selects one of the first power feeding unit and the second power feeding unit by switching are further provided. In this case, the current spreading element operates as a sub-antenna in a state where the first casing and the second casing are closed.

  With this configuration, when the performance of the dipole antenna deteriorates with the housing closed, high antenna performance can be obtained by using the conductive metal hinge element as an antenna (sub-antenna). Moreover, since the said conductive metal hinge element can be used as an antenna element (subantenna element), the said effect is acquired, without adding components newly.

  The folding portable wireless device according to the present invention can be configured such that the current spreading element is separated from the human head when used in the vicinity of the human head.

  With this configuration, it is possible to further reduce the local average SAR and improve the call gain by moving the dispersed current concentration portion away from the human body.

  Note that the first casing and the second casing constitute one of the upper casing and the lower casing and the other.

  As described above, according to the foldable portable wireless device according to the present invention, the current concentrated on the antenna element is distributed to the current spreading element, thereby reducing the local average SAR and the electromagnetic wave to the human body. The antenna performance in a talking state can be improved by the radiation from the current spreading element.

  Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
FIG. 1 shows a basic configuration of a folding portable wireless device according to the first embodiment.

  In FIG. 1, an upper case (upper housing) 1 and a lower case (lower housing) 2 form a power supply side hinge portion (conductive metal hinge element) 4a and a power supply opposite side hinge portion (conductive metal hinge element) 4b. The foldable portable radio device is configured by the structure connected by the included hinge portion. Two states of an open state and a closed state can be taken by rotating around the hinge portion including the power supply side hinge portion 4a and the power supply opposite side hinge portion 4b. The upper case 1 and the lower case 2 are made of a resin molded product that is an insulator. The feed-side hinge part 4a and the feed-opposing side hinge part 4b are made of conductive metal, have a cylindrical shape with a diameter of about 10 mm and a length of about 15 mm, respectively, and are integrated with the metal frame (antenna element) 3. Is configured.

  A metal frame 3 is attached to the surface of the upper case 1 on the + X side, that is, the surface on which the display unit is generally disposed. Here, the metal frame 3 is made of a metal having high conductivity, light weight and high strength, here, a magnesium alloy. The length of the long side of the metal frame is about 90 mm.

  The power supply terminal (first power supply part) 7 is electrically connected to the power supply side hinge part 4a by contact, and the contact resistance is set to, for example, 1Ω or less so as to facilitate electrical conduction. The power supply terminal 7 is electrically connected to the matching circuit 10 on the circuit board 5 arranged inside the lower case 2 by soldering. The circuit board 5 is a printed circuit board on which circuit components that realize various functions of the portable wireless device are mounted, and a ground pattern serving as a circuit ground potential is formed almost on the front surface. The circuit board 5 has a long side of about 90 mm.

  The current dispersive element 9 is formed of a sheet metal formed in an L shape having an overall length of approximately a quarter wavelength (here, about 30 mm in the 2 GHz band). One end of the current spreading element 9 is electrically connected to the connection terminal 6 by contact, and the other end is opened. The current spreading elements 9 are arranged in parallel with the circuit board 5 at a predetermined interval, here, about 5 mm in the X direction. The current spreading element 9 is disposed in parallel with the width direction of the folding portable radio. The width of the current spreading element 9 is about 2 mm.

  The connection terminal 6 is connected to the planar capacitive coupling element 8 on the circuit board 5 by soldering. Therefore, the planar capacitive coupling element 8 and the current spreading element 9 are electrically connected via the connection terminal 6. The planar capacitive coupling element 8 is electrically insulated from the ground pattern of the circuit board 5 and has a size of about 5 mm in the y direction and about 5 mm in the z direction, and about 1 mm in the X direction with the power supply side hinge portion 4a. And is arranged so as to overlap with the feeding-side hinge part 4a when viewed from the -X side, so that the planar capacitive coupling element 8 and the feeding-side hinge part 4a are close to each other and coupled with sufficient capacity. Designed. That is, the planar capacitive coupling element 8 and the power supply side hinge portion 4a are arranged at a predetermined interval so as to have capacitive reactance and can be electromagnetically coupled. Further, the planar capacitive coupling element 8 and the feeding element 7 are arranged at an interval of about 5 mm in the housing width direction.

  In the foldable portable radio apparatus configured as described above, the metal frame 3, the feeding side hinge portion 4a, and the feeding opposing side hinge portion 4b operate as an upper antenna element having a length of about 100 mm. The matching circuit 10 functions to match the impedance to the input impedance (generally 50Ω) of the radio circuit 11. In addition, the ground pattern of the circuit board 5 operates as a lower antenna element. That is, the metal frame 3, the power supply side hinge part 4a, the power supply opposite side hinge part 4b, and the ground pattern (including the power supply terminal 7 constituting the first power supply part) of the circuit board 5 operate as a dipole antenna.

  Here, when the current spreading element 9 is not present, most of the antenna current is concentrated on the feeding-side hinge 4a that is a feeding unit. Since the power supply side hinge 4a is close to the human body during a call, it is disadvantageous for the SAR.

  9, the same reference numerals as those in FIG. 1 denote the same components, and a detailed description thereof will be omitted.

  In FIG. 9, the length M of the current spreading element 9 is defined as M1 + M2. FIG. 9 shows the relationship between the SAR value at 1945 MHz and the call gain when the length M of the current spreading element 9 is changed in the present embodiment. When the length M of the current spreading element 9 is 37 mm (39), the SAR 10 g average is 1.53 mW / g and the call gain is -9.3 dBi, whereas when the length M is 30 mm (49) the SAR 10 g average is 1.14 mW / g. g, the call gain is −7.7 dBi, the SAR is reduced by about 25%, and the call gain is improved by 1.6 dB.

  FIG. 10 shows the radiation pattern of the polarization in the Y direction in the XZ cross section of free space at 1945 MHz, that is, the polarization pattern in the housing width direction in this embodiment. When the radiation pattern 41 when the length M of the current spreading element 9 is 37 mm and the radiation pattern 42 when the length M of the current spreading element 9 is 30 mm are compared, the radiation pattern 42 is 90 ° to 180 ° compared to the radiation pattern 41. It can be seen that the radiation in the direction opposite to the surface in contact with the human body (in the direction of the region 43) is increasing over time, that is, in a call state.

  As can be seen from the above, in the foldable portable wireless device according to the present embodiment, the antenna current concentrated on the feeding-side hinge 4a is capacitively coupled from the planar capacitive coupling element 8 to the current spreading element 9. And the current peak can be kept away from the human body. Thereby, SAR can be reduced.

  Further, by arranging the current dispersive element 9 in parallel with the width direction of the folding portable wireless device, the radiation characteristic of the polarization component in the Y direction in FIG. 1 can be obtained. At this time, as shown in FIG. 2, in a state where the folding portable wireless device is opened, a general call state in which the metal frame 3 side is directed to the human head 12 and inclined by 60 degrees from the zenith direction and held by the hand 13 2, the radiation characteristic of the Z direction component of the coordinate system of FIG. Thereby, a high antenna gain in a call state can be obtained.

  In this embodiment, the length of the current dispersive element 9 is described as about a quarter wavelength (here, 30 mm). However, the length of the current dispersive element 9 varies depending on the conditions of peripheral components and the like, and is not limited thereto. It is not a thing.

  Moreover, although the shape of the current spreading element 9 has been described as an L shape, the shape of the current spreading element 9 may be any shape that can divert the antenna current flowing through the power supply side hinge portion 4a to the current spreading element 9, For example, it may be substantially L-shaped or linear.

  Further, the current spreading element 9 has been described as being arranged in parallel with the circuit board 5 with a predetermined interval, for example, about 5 mm. However, it is only necessary that the current peak can be kept away from the human body, for example, with an interval of about 10 mm. If the circuit board 5 is arranged in parallel, the current peak is further away from the human body, so that a larger SAR reduction effect can be obtained.

  The width of the current spreading element 9 may be, for example, about 1 mm. In this case, since the bandwidth of the operating frequency is narrowed, it is desirable that the current spreading element 9 is wide.

  Further, in the present embodiment, the current spreading element 9 has been described as being arranged in parallel to the width direction of the folding portable wireless device. However, with regard to the SAR reduction effect, the antenna current flowing through the power supply side hinge portion 4a is represented by the current spreading element. Any arrangement can be used as long as it can be divided into 9, for example, in the longitudinal direction of the casing.

  In this embodiment, the metal frame 3 is operated as the upper antenna element and the circuit board 5 is operated as the lower antenna element. However, the present invention is not limited to this, and the same effect can be obtained if the antenna element feeds the hinge portion. can get. For example, a conductor such as a ground pattern or a shield case of a circuit board disposed inside the upper housing may be used as the upper antenna element.

  In the present embodiment, the hinge portion is described as a structure divided into the power supply side hinge portion 4a and the power supply opposite side hinge portion 4b. However, the hinge portion is opened and closed by rotating about the hinge portion. For example, a structure in which the power supply side hinge portion 4a and the power supply opposite side hinge portion 4b are one may be used.

(Second Embodiment)

  FIG. 3 shows a basic configuration of a folding portable wireless device according to the second embodiment.

  3, the same reference numerals as those in FIG. 1 denote the same components, and the detailed description thereof is omitted.

  In FIG. 3, the sub-antenna element (current distribution element) 14 is formed of a conductive sheet metal and is electrically connected to the power supply terminal (second power supply unit) 16 by contact. The sub-antenna element 14 has a width of about 2 mm and has a U-shape that is bifurcated from the contact point with the power supply terminal 16. The length of the sub-antenna element 14 is + Z side from the power supply terminal 16. Each element is set to approximately a quarter wavelength of the operating frequency (about 37 mm in the 2 GHz band). The power supply terminal 16 is connected to the planar capacitive coupling element 17 on the circuit board 5 by soldering.

  The power feeding terminal 15 and the power feeding terminal 16 are selected by an antenna control circuit unit (control unit) 26 mounted on the circuit board 5 and connected to the radio circuit 24. The power feeding element 15 has a configuration equivalent to that of the power feeding terminal 7 in the first embodiment.

  Here, the antenna control circuit unit 26 includes a matching circuit 18, a matching circuit 19, a high frequency switch 20, a high frequency switch 21, a termination reactance element 22, and a termination reactance element 23.

  Here, the antenna control circuit unit 26 shows a state in which the power supply terminal 15 is selected in a state where the upper housing and the lower housing of the folding portable wireless device are opened. At this time, the power supply terminal 15 is connected to the radio circuit 24 via the matching circuit 18 and the high frequency switch 20. In the antenna operation in this state, the metal frame 1 and the hinge portion and the circuit board 5 operate as a dipole antenna in substantially the same manner as shown in FIG.

  Here, the power supply terminal 16 is grounded via the matching circuit 19, the high frequency switch 21, and the terminal reactance element 23. At this time, the value of the termination reactance element 23 can be adjusted to adjust the coupling between the antennas, and the deterioration of the antenna performance due to the coupling can be reduced.

  With this configuration, the sub-antenna element 14 operates as a current spreading element in the same manner as the current spreading element 9 in FIG. Therefore, SAR can be reduced.

  Here, the control circuit 25 senses the closed state and open state of the radio using, for example, a hall element and a permanent magnet, and selects the power supply terminal 16 in the closed state and selects the power supply terminal 15 in the open state. The switch 20 and the high frequency switch 21 are operated so as to be switched. Since the antenna performance is higher when the feeding terminal 15 is selected in a state where the housing is opened, the configuration is made as described above.

  Next, a state where the housing is closed will be described with reference to FIG. In this state, the power supply terminal 16 is connected to the radio circuit 24 via the matching circuit 19 and the high frequency switch 21. The power supply terminal 15 is grounded via the matching circuit 18, the high frequency switch 20, and the terminal reactance element 22.

  Here, since the coupling between the antennas can be adjusted by adjusting the value of the termination reactance element 22, it is possible to reduce the degradation of the antenna performance due to the coupling.

  In the state where the housing is closed, the metal frame 3 shown in FIG. 1 is close to the circuit board 5 and the currents in the phases are opposite to each other. Therefore, the antenna performance when the feeding terminal 15 is selected is low. Therefore, when the casing is closed, the configuration is as described above.

  In FIG. 5, the same reference numerals as those in FIG. 3 denote the same components, and a detailed description thereof will be omitted.

  In FIG. 5, the length L of the sub-antenna element 14 is defined as L1 + L2. FIG. 5 shows the relationship between the SAR value at 1945 MHz and the call gain when the length L of the sub antenna element 14 is changed in this embodiment. When the length L of the sub-antenna element 14 is 31 mm, (27) the SAR 10g average is 1.38 mW / g and the speech gain is -7.8 dBi, whereas when the length L is 35 mm (28) the SAR 10g average is 0.57 mW / g. g, the call gain is -5.4 dBi, the SAR is reduced by about 60%, and the call gain is improved by 2.4 dB.

  6 and 7, the current distributions 29a and 33a in the regions 29b and 33b as viewed from the + X side of the upper housing and the current distributions 30a in the regions 30b and 34b as viewed from the −X side of the lower housing in this embodiment. , 34a. The frequency is 1945 MHz. 6 shows a current distribution when the length L of the sub antenna element 14 is 31 mm, and FIG. 7 shows a current distribution when the length L of the sub antenna element 14 is 35 mm. From the current distribution viewed from the + X side of the upper housing, the current intensity in the vicinity of the feeding-side hinge 4a 31, 35, and from the current distribution viewed from the −X side of the lower housing, the currents in the vicinity of the sub antenna element 32, 36 The strength of In FIG. 6, the current is concentrated in both the vicinity 31 of the power supply side hinge 4 a and the vicinity 32 of the sub antenna element 14. In FIG. 7, it can be seen that the current flowing in the vicinity 32 of the power supply side hinge portion 4 a is reduced and the current in the vicinity of the sub antenna element 14 is increased compared to FIG. 6. As a result, the SAR can be reduced because the dispersed current concentration portion moves away from the human body.

  FIG. 8 shows the radiation pattern of the polarization in the Z direction in the call state in this embodiment. The frequency is 1945 MHz. When the radiation pattern 37 when the length L of the sub antenna element 14 is 31 mm and the radiation pattern 38 when the length L of the sub antenna element 14 is 35 mm are compared, the radiation pattern 38 is deviated in the Z direction compared to the radiation pattern 37. It can be seen that the wave, that is, the polarization in the width direction of the housing increases.

  In this embodiment, the efficiency of the free space with the housing closed at 1945 MHz is −11.7 dB when the power supply terminal 15 is selected, and is −3 dB when the power supply terminal 16 is selected, and the power supply terminal 16 is selected. As a result, the antenna performance is improved by about 9 dB. Here, the efficiency of the free space is the sum of the radiated power in the 360-degree azimuth for each of the vertical and horizontal polarizations in the XZ section and the vertical and horizontal polarizations in the YZ section in FIG. Is a value compared with the reference dipole.

  As described above, according to the foldable portable wireless device of the present embodiment, the power supply side hinge portion 4a, the metal frame 3, and the circuit board 5 are selected by selecting the power supply terminal 7 when the housing is opened. Operates as an antenna, and the sub antenna element 14 operates as a current spreading element, for example, SAR can be reduced by about 60% compared to the case where the sub antenna element 14 is not provided, and the antenna gain in a call state is about 2%. .5 dB can be improved. In addition, when the housing is closed, selecting the feeding terminal 16 causes the sub-antenna element 14 to operate as an antenna (sub-antenna), and an improvement effect of 9 dB can be obtained as compared with the case where the feeding terminal 7 is selected.

  The arrangement position of the sub-antenna element 14 is not limited to that shown in the present embodiment, and the upper antenna of the lower housing can be positioned at a position where both the open antenna gain during a call and the closed antenna gain can be increased. I just need it. Specifically, it is arranged in the vicinity of the power supply side hinge 4a so as to be as far away as possible (for example, 5 mm or more), and at a position that cannot be grasped by the user's hand during an open call. This is desirable in terms of antenna performance.

  The width of the sub antenna element 14 may be, for example, about 1 mm. In this case, the bandwidth of the operating frequency is relatively narrow, and the bandwidth can be widened. A wider one is desirable.

  Further, although the shape of the sub antenna element 14 has been described as a U-shape that is bifurcated from the contact point with the power supply terminal 16, the shape of the sub antenna element 14 is the antenna current flowing through the power supply side hinge portion 4a. For example, the shape may be a substantially L shape or a linear shape.

  Even when the reactance element 23 is not present, the effect of adding the sub-antenna element 14 can be obtained. However, when the sub-antenna element 14 and the reactance element 23 are simultaneously added and used together, the effect is higher. can get.

  Further, in the present embodiment, the configuration is such that the high frequency switch is switched by detecting the open state and the closed state of the folding portable wireless device. However, the present invention is not limited to this. For example, the high frequency switch is switched according to the reception level of the wireless circuit 24. It is good also as a structure.

  Although various embodiments of the present invention have been described above, the present invention is not limited to the matters shown in the above-described embodiments, and those skilled in the art can change or modify them based on the description and drawings, and well-known techniques. Application is also within the scope of the present invention and is within the scope of protection.

  As described above, since the local average SAR can be reduced, the present invention is useful for the purpose of reducing the influence of electromagnetic waves radiated from the use of the folding portable radio device on the human body. In addition, since high antenna performance can be obtained in a call state, call quality can be improved. Further, since high antenna performance can be obtained even when the housing is closed, standby sensitivity can be improved. This is useful for improving the wireless communication performance of tatami-type portable radios.

The figure which shows the state which opened the housing | casing of the foldable portable radio | wireless machine which concerns on 1st Embodiment. The figure which shows a telephone call state. The figure which shows the state which opened the housing | casing of the foldable portable radio | wireless machine which concerns on 2nd Embodiment. The figure which shows the state which closed the housing | casing of the foldable portable radio | wireless machine which concerns on 2nd Embodiment. The figure which shows the change of SAR and a call gain when changing the length L of the subantenna element 14 in 2nd Embodiment. The figure which shows electric current distribution when the length L of the subantenna element 14 is 31 mm in 2nd Embodiment. The figure which shows electric current distribution when the length L of the subantenna element 14 is 35 mm in 2nd Embodiment. The figure which shows the radiation pattern in the telephone call state when the length L of the subantenna element 14 is 31 mm and 35 mm in 2nd Embodiment. The figure which shows the change of SAR and a call gain when changing the length M of the electric current dispersion element 9 in 1st Embodiment. The figure which shows the radiation pattern in the free space when the length M of the electric current dispersion element 9 is 37 mm in 1st Embodiment, and when it is 30 mm.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Upper case 2 Lower case 3 Metal frame 4a Feeding side hinge part 4b Feeding side hinge part 5 Circuit board 6 Connection terminal 7 Feeding terminal 8 Planar capacitive coupling element 9 Current distribution element 10 Matching circuit 11 Radio circuit 12 Human head 13 Hand 14 Sub-antenna element 15 Feed terminal 16 Feed terminal 17 Planar capacitive coupling element 18 Matching circuit 19 Matching circuit 20 High-frequency switch 21 High-frequency switch 22 Reactance element 23 Reactance element 24 Radio circuit 25 Control circuit 26 Antenna control circuit section 27 Sub-antenna element 14 SAR and call gain 28 when the length L of the antenna is 31 mm SAR and call gain 29a when the length L of the sub-antenna element 14 is 35 mm Current distribution 29b seen from the + X side of the upper housing Upper part seen from the + X side Case part 30a Current distribution 30b seen from -X side of lower case Seen from -X side Upper housing portion 31 Near power feeding hinge portion 4a Near sub antenna element 14 Near 33a Current distribution 33b seen from + X side of upper housing Upper housing portion 34a seen from + X side Seen from -X side of lower housing Current distribution 34b Lower housing portion 35 viewed from the X side vicinity of feeding-side hinge 4a 36 vicinity of sub antenna element 14 37 radiation pattern 38 when sub antenna element 14 has a length L of 31 mm length of sub antenna element 14 Radiation pattern 39 when L is 35 mm SAR and speech gain 40 when current dispersion element 9 length M is 37 mm SAR and speech gain 41 when current dispersion element 9 length M is 30 mm Radiation pattern 42 when the length M is 37 mm Radiation pattern 43 when the length M of the current spreading element 9 is 30 mm Opposite to the surface in contact with the human body in a talking state Area of

Claims (4)

A first housing;
A second housing;
A hinge portion that connects the first housing and the second housing so as to be freely opened and closed;
(A) an antenna element provided in the first casing; (b) a conductive metal hinge element electrically connected to the antenna element and provided in the hinge; and (c) the second A dipole antenna comprising: a first power feeding unit that feeds power to the conductive metal hinge element from a circuit board provided in the housing of
A planar capacitive coupling element provided in the circuit board and provided at a predetermined interval so as to have capacitive reactance with the conductive metal hinge element;
A foldable portable wireless device comprising: a current sharing element that has one end electrically connected to the planar capacitive coupling element and the other end open to distribute a current flowing through the dipole antenna. The foldable portable wireless device according to claim 1,
The current dispersive element has a length of approximately ¼ with respect to a wavelength of a desired frequency, and an antenna current flowing through the conductive metal hinge element flows from the planar capacitive coupling element to the current dispersive element. Thus, the folding portable wireless device disperses the antenna current concentrated on the hinge portion. The folding portable wireless device according to claim 1 or 2,
A foldable portable wireless device in which the current spreading element is disposed in a width direction of the first casing and the second casing. The foldable portable wireless device according to claim 1, wherein
A second power feeding unit that feeds power from the circuit board to the current spreading element;
And a control unit that selects one of the first power feeding unit and the second power feeding unit by switching, and the current spreading element closes the first housing and the second housing. A foldable portable wireless device that operates as a sub-antenna in a closed state.

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