JP2007158915A - Walkie-talkie - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a walkie-talkie which prevents degradation of the frequency characteristics of the impedance and the antenna characteristics, and has the antenna element built-in so as to maintain compact size. <P>SOLUTION: The walkie-talkie 1 is provided with a first circuit board 5, a second circuit board 6 connected electrically with the first circuit board, a first case 2 for housing the first circuit board, a second case 3 which houses the second circuit board and is linked with the first case, the antenna element 7 which the first case has incorporated within, and a feeding portion arranged on the first circuit board and connected electrically to the antenna element. The first circuit board has a non-grounded region formed in an edge region on the second case side, and a grounded region other than the ungrounded region. The feed portion is arranged in the ungrounded region of the first circuit board, and 80% or more of the total length of the antenna element will not exist on the first circuit board. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a portable wireless device, for example, a mobile phone, and more particularly to a portable wireless device mainly having two housings.

  In recent years, from the viewpoint of design, a large number of portable wireless devices with a built-in antenna in which an antenna is arranged in a housing have been provided. In addition, in the overall design, a large number of folding or sliding portable wireless devices in which the housing is mainly divided into two parts are also provided. On the other hand, in terms of functions, the multi-functionality and high functionality of portable wireless devices are progressing. For example, a portable wireless device includes a camera function, a large-capacity memory, a recording function to a removable recording medium, a music / video playback / recording function, a television / radio function, a large display, and the like. In order to achieve such built-in antennas and multi-function / high functionality, it is necessary to secure space for the parts built in the portable wireless device while satisfying the design requirements and avoiding the enlargement of the portable wireless device itself. Don't be.

  In the folding portable wireless device, various configurations for incorporating an antenna have been proposed. In a foldable portable wireless device having two housings, if the housing with the earphone unit and the display unit is the upper housing and the housing with the microphone unit and the key operation unit is the lower housing, for example, the upper housing and the lower housing A built-in antenna embedded in a hinge portion that joins the housing (see Patent Document 1), a built-in antenna disposed on a circuit board in the upper housing (see Patent Documents 2 and 3), an upper housing, There is known one in which a built-in antenna is provided on each circuit board in a lower housing (see Patent Document 4).

JP 2004-96302 A JP 2004-128604 A JP 2001-156898 A JP 2004-201179 A

  In a portable wireless device incorporating an antenna element, if the antenna element is disposed on a circuit board, the frequency characteristics of the antenna input impedance deteriorate. That is, there is a possibility that a desired impedance value can be obtained only in a specific frequency band. Furthermore, if the area on the circuit board is occupied by the antenna element, it becomes difficult to achieve high functionality / multifunction and to keep downsizing.

  Further, in a foldable portable wireless device having two casings as described in Patent Documents 1 to 4, the location in which the antenna element is incorporated is important. If the antenna element is built in the lower housing, the antenna gain is lowered because the lower housing is usually covered with a hand. Similarly, since there is a high possibility that the hinge part is also covered with a hand, it is preferable to avoid disposing the antenna element on the hinge part. In addition, it is difficult to incorporate the antenna element from the viewpoint of the structure and space of the hinge part, and a flexible cable that electrically connects the circuit board of the upper housing and the circuit board of the lower circuit passes through the hinge part. If the element and the flexible substrate are adjacent to each other, problems such as deterioration of antenna characteristics and generation of noise may occur.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a portable wireless device incorporating an antenna element so as to avoid deterioration of impedance frequency characteristics and antenna characteristics and to maintain miniaturization.

  According to the basic form of the present invention, a first circuit board, a second circuit board electrically connected to the first circuit board, a first housing for housing the first circuit board, and a second circuit board are provided. A power supply that is housed and connected to the first housing, an antenna element built in the first housing, and a first circuit board and electrically connected to the antenna element The first circuit board includes a non-ground area formed in an edge area on the second housing side, and a ground area other than the non-ground area. Provided is a portable radio device that is arranged in a non-ground region and has 80% or more of the total length of the antenna element not existing on the first circuit board.

  According to a preferred embodiment of the present invention, 80% or more of the total length of the antenna element is arranged outside the first circuit board on the second housing side. According to another preferred embodiment, the antenna element portion arranged outside the first circuit board extends along the end of the first circuit board as a whole. According to another preferred embodiment, the first housing and the second housing are rotatably coupled via the hinge portion. According to another preferred embodiment, the portable wireless device of the present invention includes an earphone unit and a display unit disposed in the first housing, and a microphone unit and a key operation unit disposed in the second housing. Further prepare. According to another preferred embodiment, the portable radio of the present invention electrically connects a radio circuit disposed on the second circuit board, a radio circuit on the second circuit board, and a power feeding unit on the first circuit board. A coaxial line, and the central conductor of the coaxial line is connected to the power feeding unit and the radio circuit, and the outer conductor of the coaxial line is connected to the ground regions of the first circuit board and the second circuit board, respectively.

  According to the present invention, first, no antenna element is disposed on the ground area of the circuit board. Thereby, the influence on the antenna element by the ground region can be reduced. That is, the impedance frequency characteristic of the antenna element is improved, and a low impedance can be obtained at a wide frequency range. Secondly, according to the present invention, most of the antenna elements are disposed outside the circuit board. This can also reduce the influence of the ground region on the antenna element. In addition, by arranging the antenna elements between the circuit board and the casing, the occupation ratio of the antenna elements on the circuit board is reduced, and the space in the casing can be effectively used. According to the present invention, third, the antenna element is disposed in the vicinity of the connecting portion with the other casing. As a result, the antenna element can be disposed in the vicinity of the connecting portion of the housing that can easily secure a space, and the space in the housing can be effectively utilized. According to the present invention, fourthly, the antenna element and the power feeding unit are disposed in the casing that is not held by hand when talking or inputting characters. Thereby, the influence on the antenna gain degradation by a human body can be reduced.

  FIG. 1 shows a schematic perspective view of the portable wireless device according to the first embodiment of the present invention. In FIG. 1, the external structure such as a housing is indicated by a thick line, and the internal structure such as a circuit board is indicated by a thin line. 2 is a schematic plan view focusing on the internal structure of the portable wireless device shown in FIG. In FIG. 2, the external structure such as the housing is indicated by a dotted line, and the internal structure such as a circuit board is indicated by a solid line. The portable wireless device 1 has a first housing 2 and a second housing 3 made of a non-conductive material, for example, a resin, and the first housing 2 and the second housing 3 are rotated by a hinge portion 4. It is a foldable portable radio that can be connected. The first housing 2 houses the first circuit board 5, and the second housing 3 houses the second circuit board 6. The first circuit board 5 and the second circuit board 6 are electrically connected by a flexible cable 11 passing through the hinge portion 4 or the vicinity thereof. The first housing 2 further includes an earphone unit and a display unit (not shown). The second housing 3 further includes a microphone unit and a key operation unit (not shown). Therefore, in the portable wireless device 1 of the present invention shown in FIGS. 1 and 2, the first housing 2 is the upper housing, the second housing 3 is the lower housing, and the user holds the second housing 3 by hand. It is designed to be used by holding.

Here, the first circuit board 5 has a ground region 5b that functions as a ground and a non-ground region 5c that does not function as a ground. The non-ground region 5c is formed in an edge region on the second housing 3 side (lower side), and the ground region 5b is a region other than the non-ground region 5c, and is on the opposite side (upper side) of the second housing 3. ). In the form shown in FIG. 2, the first circuit board 5 is roughly divided into two in the vertical direction, and the upper side is a ground region 5b and the lower side is a non-ground region 5c. The total length (or maximum length) of the first circuit board 5 in the vertical direction is L ₁ , the total length (or maximum length) of the ground region 5b in the same direction is L ₂ , and the total length (or the non-ground region 5c in the same direction) When L ₃ is the maximum length), L ₃ (= L ₁ -L ₂ ) is preferably 5 mm or more, and L ₃ (= L ₁ -L ₂ ) is 7 mm or more if allowed by space. And preferred.

  In the non-ground region 5 c of the first circuit board 5, a power feeding unit 8 is disposed. The antenna element 7 is connected to the power feeding unit 8. In the first embodiment shown in FIG. 2, a columnar antenna element 7 is illustrated. The antenna element 7 is connected to the power feeding portion 8 so as to extend in the direction of the outside of the first circuit board 5, and most of the antenna element 7 does not exist on the first circuit board 5. At this time, it is preferable that 80% or more, more preferably 90% or more of the total length of the antenna element 7 does not exist on the first circuit board 5 (exists outside the first circuit board 5). The antenna element 7 extends from the power supply unit 8 to the outside of the first circuit board 5, and then extends so as to translate with the edge 5 a on the second housing 3 side (lower side) of the first circuit board 5. Yes. According to such a configuration, the antenna element 7 includes the end (lower end) 5a on the second casing side of the first circuit board 5 and the end (lower end) of the inner surface of the first casing 2 on the second casing 3 side. ) 2a (near the hinge). As a result, the antenna element 7 can be separated from the ground region 5b of the first circuit board 5, and the antenna element 7 can be disposed in the vicinity of the hinge portion 4 where a space can be easily secured. At the same time, the occupation on the first circuit board 5 by the antenna element 7 can be avoided.

  The radio circuit 10 is disposed on the second circuit board 6. The radio circuit 10 and the power feeding unit 8 are connected via a coaxial line 9 passing through the hinge unit 4 or the vicinity thereof. The central conductor of the coaxial line 9 is connected to the radio circuit 10 and the power supply unit 8, and the outer conductor of the coaxial line 9 is connected to the ground area 5 b of the first circuit board 5 and the ground area (not shown) of the second circuit board 6, respectively. It is connected.

  According to this embodiment, power is supplied from the radio circuit 10 to the antenna element 7 through the coaxial line 9 and the power feeding unit 8. Radio waves are radiated from the antenna element 7. For this reason, the current concentrates on the first circuit board 5 and the current hardly concentrates on the second circuit board 6. Thereby, even if it is a case where the 2nd housing | casing 3 which accommodates the 2nd circuit board 6 in which an electric current does not concentrate is grasped by hand or covered, the fluctuation | variation and loss of antenna impedance can be made small.

  FIG. 3 shows a schematic plan view of a portable wireless device according to the second embodiment of the present invention. In the first embodiment, the ground area 5b and the non-ground area 5c of the first circuit board 5 are vertically divided into a rectangular shape by one line, and the non-ground area 5c occupies the entire width of the first circuit board 5. is doing. On the other hand, in the second embodiment, the non-ground region 5c occupies only a part (left side) of the width of the first circuit board 5, and the rest (right side) is covered with the ground region 5b. The width of the non-ground region 5c is the same as or slightly larger than the width in which the antenna element 7 extends. In the second embodiment shown in FIG. 3, the shape of the antenna element 7 is a meander shape, and the antenna element 7 portion outside the first circuit board 5 is located at the lower end of the first circuit board 5 as a whole. Extending along. In the drawing, the plate surface of the antenna element 7 is illustrated so as to face the same direction as the surface of the first circuit board 5. However, this is to show the shape of the antenna element 7, and the plate surface of the antenna element 7 is arranged between the first circuit board 5 and the first housing 2, and the plate surface of the antenna element 7 is the first circuit board 5. Needless to say, it can be arranged so as to be perpendicular to the plane (that is, the volume occupied by the antenna element 7 is reduced).

  FIG. 4 shows a schematic plan view of a portable wireless device according to the third embodiment of the present invention. In the third embodiment, the non-ground region 5c of the first circuit board 5 is formed at the corner of the first circuit board 5 (lower left corner in FIG. 4). At this time, the size of the non-ground region 5c is such a size that the power supply unit 8 can be disposed, and the shape thereof is, for example, a rectangular shape of 5 mm to 7 mm square. In the third embodiment shown in FIG. 4, the shape of the antenna element 7 is spiral, and the antenna element 7 portion outside the first circuit board 5 is located at the lower end of the first circuit board 5 as a whole. Extending along.

  FIG. 5 is a schematic plan view of a portable wireless device according to the fourth embodiment of the present invention. In the fourth embodiment, the non-ground region 5c of the first circuit board 5 is formed at the corner of the first circuit board 5 (lower left corner in FIG. 5). At this time, the size of the non-ground region 5c is such a size that the power feeding unit 8 can be disposed, and the shape thereof is, for example, a circle having a diameter of 5 to 7 mm. In the fourth embodiment shown in FIG. 5, the antenna element 7 has a plate shape, and the antenna element 7 portion outside the first circuit board 5 is located at the lower end of the first circuit board 5 as a whole. Extending along. In the drawing, the plate surface of the antenna element 7 is illustrated so as to face the same direction as the surface of the first circuit board 5. However, this is to show the shape of the antenna element 7, and the plate surface of the antenna element 7 is arranged between the first circuit board 5 and the first housing 2, and the plate surface of the antenna element 7 is the first circuit board 5. Needless to say, it can be arranged so as to be perpendicular to the plane (that is, the volume occupied by the antenna element 7 is reduced).

  In a foldable mobile phone composed of a first casing (upper casing) and a second casing (lower casing), a portable wireless device having an antenna element built in the first casing and an antenna element built in the second casing For each of the portable wireless devices, the degree of influence of the human body, particularly the hand holding the second housing, on the antenna characteristics was measured. FIG. 2 shows a form in which the antenna element is built in the first casing, and FIG. 6 shows a form in which the antenna element is built in the second casing. The locations where the antenna elements were built were in the vicinity of the hinge portions, and most of the antenna elements were positioned between the circuit board and the inner surface of the casing on the hinge portion side. First, as a reference value, the output of the dipole antenna was measured using a small transmitter that supplies a small amount of power to the antenna element in an anechoic chamber. Next, the antenna output of each of the portable wireless device incorporating the antenna element in the first housing and the portable wireless device incorporated in the second housing was measured. As a measurement method, a measurement cable was attached to the antenna element of the portable wireless device, and a small transmitter used for the reference value measurement was attached thereto. Then, in the anechoic chamber, each antenna output was measured with the portable wireless device held by hand. The position of the hand holding the portable radio was the same.

  The measurement results are shown in Table 1. The results shown in Table 1 are shown as relative values based on the results when the antenna elements are arranged in the second housing. In both conditions, the antenna element was built in the vicinity of the hinge portion, but the excellent antenna characteristics were obtained by the portable radio built in the first housing. From this, it was confirmed that the bad influence by the human body can be reduced by arranging the antenna element in the vicinity of the hinge portion of the first housing.

  In the above, the embodiment of the present invention has been described by taking a mobile phone as an example. However, the present invention is not limited to a mobile phone, but can be applied to a portable electronic communication device having a wireless communication function, such as a PDA or a notebook computer. Needless to say.

1 is a schematic perspective view of an external structure and an internal structure of a portable wireless device according to a first embodiment of the present invention. 1 is a schematic plan view of a portable wireless device according to a first embodiment of the present invention. The schematic plan view of the portable radio which concerns on 2nd Embodiment of this invention. The schematic plan view of the portable radio which concerns on 3rd Embodiment of this invention. The schematic plan view of the portable radio which concerns on 4th Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic plan view of a portable wireless device serving as a comparative reference in an embodiment.

Explanation of symbols

1 portable radio 2 first housing (upper housing)
2a Lower end 3 of the inner surface of the first housing 3 Second housing (lower housing)
4 Hinge part 5 1st circuit board (upper circuit board)
5a Lower end portion 5b of first circuit board Ground area 5c Non-ground area 6 Second circuit board (lower circuit board)
7 Antenna element 8 Feeding section 9 Coaxial line 10 Radio circuit 11 Flexible cable

Claims (6)

A first circuit board;
A second circuit board electrically connected to the first circuit board;
A first housing that houses the first circuit board;
A second housing that houses the second circuit board and is coupled to the first housing;
An antenna element built in the first housing;
A power feeding portion disposed on the first circuit board and electrically connected to the antenna element;
The first circuit board has a non-ground region formed in an edge region on the second housing side, and a ground region other than the non-ground region,
The power feeding unit is disposed in the non-ground region of the first circuit board,
80% or more of the total length of the antenna element does not exist on the first circuit board.   The portable wireless device according to claim 1, wherein 80% or more of the total length of the antenna element is arranged outside the first circuit board on the second housing side.   3. The portable radio according to claim 1, wherein the antenna element portion disposed outside the first circuit board extends along an end portion of the first circuit board as a whole. Machine.   The portable wireless device according to any one of claims 1 to 3, wherein the first housing and the second housing are rotatably connected via a hinge portion. An earphone unit and a display unit disposed in the first housing;
The portable wireless device according to any one of claims 1 to 4, further comprising a microphone unit and a key operation unit disposed in the second casing. A radio circuit disposed on the second circuit board;
A coaxial line that electrically connects the wireless circuit of the second circuit board and the power feeding portion of the first circuit board;
The central conductor of the coaxial line is connected to the power feeding unit and the radio circuit,
The portable wireless device according to any one of claims 1 to 5, wherein an outer conductor of the coaxial line is connected to a ground region of each of the first circuit board and the second circuit board.

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