JP3959332B2 - Portable wireless terminal - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an antenna structure used in a communication device such as a foldable mobile phone terminal, a method for using the antenna structure, and a communication device.
[0002]
[Prior art]
  Mobile phone terminals are rapidly becoming smaller and thinner. In addition, the incorporation of antennas in mobile phone terminal housings has become a worldwide trend.
[0003]
  FIG. 19 shows a configuration of a built-in antenna of a conventional mobile phone terminal (see, for example, Patent Document 1).
[0004]
  FIG. 19A is a perspective view schematically showing a configuration of a built-in antenna of a conventional mobile phone terminal, and FIG. 19B is a side view thereof. In FIGS. 19A and 19B, an antenna element 1201 transmits and receives radio waves from a mobile phone terminal. A communication case built in a shield case 1206 and a shield case 1206 is provided on a substrate 1202. A wireless circuit 1207 is arranged. The LCD display 1203 displays information processed by the mobile phone terminal.
[0005]
  The antenna element 1201 is fed from a feeding point 1204 on the substrate 1202 and is electrically connected to a part of the substrate 1202 through a conductive connection portion 1205 at an end portion thereof. Here, a part of the substrate 1202 and the shield case 1206 are electrically connected to each other and serve as a ground plane of the antenna element 1201. Accordingly, the antenna element 1201, a part of the substrate 1202, and the shield case 1206 constitute a built-in antenna.
[0006]
  Such mobile phone terminals have not only been used as conventional telephones but also transformed into data terminals that send and receive e-mails and browse web pages via the WWW. It has been.
[0007]
  Under such circumstances, a foldable mobile phone terminal that is suitable for downsizing of a mobile phone terminal and considered to be suitable for an increase in the screen size of a display has become widespread.
[0008]
  In foldable mobile phone terminals, whip antennas are conventionally used as antennas in addition to built-in antennas. The built-in antenna and the whip antenna are both used in a state where the foldable mobile phone terminal is folded and in a state where the foldable mobile phone terminal is not folded. In general, the impedance of the antenna changes between when the foldable mobile phone terminal is folded and when it is not folded. Therefore, each of the built-in antenna and the whip antenna is adjusted so as to absorb such a difference in impedance, both when the folding cellular phone terminal is folded and when the folding cellular phone terminal is not folded. It has good characteristics.
[0009]
  FIG. 20 shows the configuration of the built-in antenna portion of the foldable mobile phone terminal. FIG. 20A is a front view of such a foldable mobile phone terminal, and FIG. 20B is a side view thereof.
[0010]
  In the foldable mobile phone terminal, the upper housing 102 and the lower housing 103 are coupled via a hinge portion 104, and the upper housing 102 and the lower housing 103 can be folded via the hinge portion 104. It is the composition.
[0011]
  A display 109 is built in the upper housing 102, an upper ground plate 207 is built in the back side of the display 109, and an upper built-in antenna element 205 is built in the opposite side of the upper ground plate 207 from the display 109. Yes.
[0012]
[Patent Document 1]
        JP 2002-223114 A
[0013]
[Problems to be solved by the invention]
  However, when using a foldable mobile phone terminal, the whip antenna needs to be pulled out from the case of the mobile phone terminal, and after use, it must be stored in the case of the mobile phone terminal. In addition, the whip antenna has a problem that it may be damaged by such a pulling-out operation and a storing operation.
[0014]
  Thus, in a foldable portable wireless terminal such as a foldable mobile phone terminal, the whip antenna requires a pull-out and storage operation, which is troublesome and has a problem that it is easily damaged by such an operation.
[0015]
  In the foldable mobile phone terminal shown in FIG. 20, the upper internal antenna element 205, the upper base plate 207, and the lower base plate 208 constitute an upper internal antenna. In this case, the upper ground plane 207 and the lower ground plane 208 are electrically connected, and the upper ground plane 207 and the lower ground plane 208 function as a ground plane of the upper internal antenna.
[0016]
  When the mobile phone terminal is folded, the ground plate of the antenna composed of the upper ground plate 207 and the lower ground plate 208 is also folded. It becomes half. In this case, when the length of the upper ground plane 207 is shorter than ¼ wavelength, the standing wave of the current does not exist on the ground plane in the desired frequency band, so the contribution of the ground plane to the radiation of the radio wave from the antenna becomes small. End up.
[0017]
  Accordingly, when using the upper internal antenna when the mobile phone terminal 201 is folded and when not folded, in addition to being able to absorb the change in impedance characteristics between when folded and when not folded, An antenna having a broadband characteristic that can absorb the change in contribution to the radiation of the ground plane is required.
[0018]
  In other words, the antenna of the foldable mobile phone terminal needs to have good characteristics both when the mobile phone terminal is folded and when it is not folded. There is a problem of becoming.
[0019]
  For this reason, even if the thickness of parts other than the upper internal antenna built into the upper housing 102 such as the display 109 is made thinner, the thickness of the upper internal antenna becomes an obstacle, and the thickness of the upper housing 102 is reduced. Can not do it. Similarly, even if the thickness of the parts other than the lower internal antenna built in the lower housing 103 is made thinner, the thickness of the lower internal antenna becomes an obstacle, and the thickness of the lower housing 103 is reduced. It is not possible. As described above, in a portable wireless terminal such as a foldable mobile phone terminal, there is a problem that the thickness of the foldable portable wireless terminal increases when the built-in antenna is used.
[0020]
  In consideration of the above problems, the present invention does not require an antenna pull-out operation or storage operation when a foldable portable wireless terminal is used.Portable wireless terminalIs intended to provide.
[0021]
  Further, the present invention can further reduce the thickness of a foldable mobile phone terminal in consideration of the above problems.Portable wireless terminalIs intended to provide.
[0022]
[Means for Solving the Problems]
  In order to solve the above-described problem, the first aspect of the present invention provides:A portable wireless terminal that transmits and receives signals via a duplexer,
  A first housing part;
  A second housing part;
  A first antenna disposed in the first housing portion;
  A second antenna disposed in the second housing portion;
  A transmission circuit;
  A receiving circuit,
  The first casing part and the second casing part are configured to be foldable via a hinge part,
  The first and second antennas areSwitched by the duplexer,Transmit / receive in a desired communication frequency band,
  When receiving,By switching with the duplexer,When the portable wireless terminal is not folded, the first antenna functions as a main antenna and the second antenna functions as a sub-antenna, and when the portable wireless terminal is folded, A second antenna as a main antenna and the first antenna as a sub-antenna;
  When sending,By switching with the duplexer,Reception between the first antenna and the second antennaSelected as the main antenna whenIt is a portable radio terminal using an antenna.
[0023]
[0024]
[0025]
[0026]
[0027]
  The second2In the present invention, the first antenna is a built-in antenna built in the first housing portion,
  The second antenna is a built-in antenna built in the second casing.1'sOf the present inventionPortable wireless terminalIt is.
[0028]
  The second3In the present invention, the first antenna includes an antenna element and a ground plane for the antenna element.1'sOf the present inventionPortable wireless terminalIt is.
[0029]
[0030]
[0031]
[0032]
[0033]
[0034]
[0035]
[0036]
[0037]
[0038]
  The second4In the present invention, a part of the first casing part and / or the second casing part has conductivity,
  The conductive part is used as the ground plane.3Of the present inventionPortable wireless terminalIt is.
  According to a fifth aspect of the present invention, the second casing portion has a closed loop-shaped protrusion on the arrangement surface of the hinge portion, and at least a part of the protrusion is used as the second antenna. It is a portable wireless terminal according to any one of the first to fourth aspects of the present invention that is functioning.
[0039]
[0040]
[0041]
[0042]
[0043]
[0044]
[0045]
[0046]
[0047]
[0048]
[0049]
[0050]
[0051]
[0052]
DETAILED DESCRIPTION OF THE INVENTION
  Below, the present inventionReference examples andEmbodiments will be described with reference to the drawings.
[0053]
  (Reference example)
  First,Reference exampleWill be described.
[0054]
  Figure 1Reference exampleThe structure of the foldable mobile phone terminal 201 is shown. The foldable mobile phone terminal 201 does not have a whip antenna but is configured only from a built-in antenna. FIG. 1A is a front view of such a foldable mobile phone terminal 201, and FIG. 1B is a side view thereof.
[0055]
  In the foldable mobile phone terminal 201, the upper housing 102 and the lower housing 103 are coupled via a hinge portion 104, and the upper housing 102 and the lower housing 103 are folded via the hinge portion 104. It has a possible configuration. Further, the upper housing 102 and the lower housing 103 are electrically connected via the hinge portion 104.
[0056]
  A display 109 is built in the upper housing 102, an upper ground plate 207 is built in the back side of the display 109, and an upper built-in antenna element 205 is built in the opposite side of the upper ground plate 207 from the display 109. Yes.
[0057]
  The upper internal antenna element 205 and the upper ground plane 207 constitute an upper internal antenna. The upper internal antenna is adjusted to have good characteristics both when the foldable mobile phone terminal 201 is folded and when the foldable mobile phone terminal 201 is not folded.
[0058]
  In addition, the lower housing 103 incorporates a key 110, and a lower ground plane 208 and a lower internal antenna element 206 are incorporated on the back surface of the key 110. The lower housing 103 also has a built-in microphone (not shown) for inputting sound.
[0059]
  The lower internal antenna element 206 and the lower base plate 208 constitute a lower internal antenna. The lower built-in antenna is adjusted to have good characteristics both when the foldable mobile phone terminal 201 is folded and when the foldable mobile phone terminal 201 is not folded.
[0060]
  Then like thisReference exampleThe operation of will be described.
[0061]
  The mobile phone terminal 201 performs diversity reception and diversity transmission.
[0062]
  That is, the upper internal antenna and the lower internal antenna are used for diversity reception. Therefore, each of the upper internal antenna and the lower internal antenna is used both when the foldable mobile phone terminal 201 is folded and when the foldable mobile phone terminal 201 is not folded.
[0063]
  Since the upper internal antenna and the lower internal antenna are both adjusted to have good characteristics when the cellular phone terminal 201 is folded and not folded, the instantaneous signal level due to fading in a multi-wave propagation environment The drop in fluctuation can be remedied, and the interruption of communication can be avoided.
[0064]
  In addition, since the mobile phone terminal 201 does not use a whip antenna, when using the mobile phone terminal 201, the whip antenna is pulled out one by one, or after using the mobile phone terminal 201, the whip antenna is connected to the mobile phone terminal. It is not necessary to store in the housing 201. Therefore, it does not take time to use the mobile phone terminal 201, and there is no fear of damage due to the antenna pull-out operation and storage operation.
[0065]
  (No.1Embodiment)
  Next1The embodiment will be described.
[0066]
  FIG. 2 shows a mobile phone terminal 101 according to the present embodiment. 2A is a front view of the mobile phone terminal 101, and FIG. 2B is a side view thereof. The cellular phone terminal 101 is a foldable type and uses only a built-in antenna.
[0067]
  In the mobile phone terminal 101, an upper housing 102 and a lower housing 103 are coupled via a hinge portion 104, and the upper housing 102 and the lower housing 103 can be folded via the hinge portion 104. It is configured.
[0068]
  A display 109 is built in the upper housing 102, an upper ground plate 107 is built in the back side of the display 109, and an upper built-in antenna element 105 is built in a side opposite to the display 109 of the upper ground plate 107. Yes. The upper internal antenna element 105, the upper ground plane 107, and the lower ground plane 108 constitute an upper internal antenna. In this case, the upper ground plane 107 and the lower ground plane 108 are electrically connected, and the upper ground plane 107 and the lower ground plane 108 function as the ground plane of the upper internal antenna.
[0069]
  This upper internal antenna is adjusted to have good characteristics when the cellular phone terminal 101 is not folded.
[0070]
  The lower housing 103 has a key 110 built therein, and a lower ground plane 108 and a lower built-in antenna element 106 are built in the back side of the key 110. The lower housing 103 also has a built-in microphone (not shown) for inputting sound.
[0071]
  The lower internal antenna element 106, the upper ground plane 107, and the lower ground plane 108 constitute a lower internal antenna. In this case, the upper ground plane 107 and the lower ground plane 108 are electrically connected, and the upper ground plane 107 and the lower ground plane 108 function as a ground plane of the lower internal antenna.
[0072]
  This lower internal antenna is adjusted to have good characteristics when the cellular phone terminal 101 is folded.
[0073]
  Next, the operation of this embodiment will be described.
[0074]
  The cellular phone terminal 101 according to the present embodiment performs radio communication with a base station (not shown) using a frequency band of 800 MHz.
[0075]
  When the cellular phone terminal 101 is not folded, the upper internal antenna is used. That is, the upper internal antenna is fed. On the other hand, when the mobile phone terminal 101 is folded, the lower internal antenna is used. That is, the lower internal antenna is fed.
[0076]
  When the mobile phone terminal 101 is used without being folded, the user of the mobile phone terminal 101 usually makes a call while holding the lower casing 103 by hand. At this time, the upper housing 102 is not held by a user's hand or the like. Therefore, when the mobile phone terminal 101 is used in a state where it is not folded, the gain of the upper internal antenna is lower than that of the lower internal antenna due to the influence of the human body. Therefore, in this case, by using the upper internal antenna, it is possible to further suppress a decrease in gain due to the influence of the human body.
[0077]
  On the other hand, when the mobile phone terminal 101 is used in a folded state, the user of the mobile phone terminal 101 puts the mobile phone terminal 101 in a chest pocket or puts it on a desk or table. In this case, since the cellular phone terminal 101 is folded, the upper internal antenna is not used and the lower internal antenna is used. In this case, if the upper internal antenna functions as a parasitic element for the lower internal antenna and the upper internal antenna is arranged so as to have predetermined directivity and wideband frequency characteristics, the transmission wave is transmitted in a predetermined direction. The directivity can be formed so as to radiate strongly, and at the same time it can have broadband characteristics.
[0078]
  FIG. 3A shows a state where the cellular phone terminal 101 is folded and placed in the breast pocket. The human chest is present in the direction P in FIG. When the lower housing 103 is on the chest side of the human body and the upper housing 102 is on the opposite side of the human chest, the upper internal antenna functions as a parasitic element, and the load of the parasitic element By adjusting, it becomes possible to form a directivity that strongly radiates a transmission wave on the opposite side of the human body from the chest. In addition, it is expected that a wide band characteristic can be realized by adjusting the electromagnetic coupling between the upper internal antenna and the lower internal antenna functioning as a parasitic element. Therefore, when the mobile phone terminal 101 is stored in the breast pocket in the state as shown in FIG. 3A, a decrease in gain due to the influence of the human body can be suppressed.
[0079]
  FIG. 3B shows a state where the mobile phone terminal 101 is folded and placed on an iron table. There is an iron table in the direction of Q in FIG. In this case, since the cellular phone terminal 101 is folded, the upper internal antenna is not used and the lower internal antenna is used. When the lower housing 103 is on the iron table side and the upper housing 102 is on the opposite side of the iron table side, the upper internal antenna functions as a parasitic element, By adjusting the load, it is possible to form a directivity that strongly radiates a transmission wave on the side opposite to the iron table. In addition, it is expected that a wide band characteristic can be realized by adjusting the electromagnetic coupling between the upper internal antenna and the lower internal antenna functioning as a parasitic element. Therefore, when the mobile phone terminal 101 is placed on the table in the state as shown in FIG. 3B, a decrease in gain due to the influence of the table can be suppressed.
[0080]
  Further, when the mobile phone terminal 101 is not folded, the upper internal antenna is used, and when the mobile phone terminal 101 is folded, the upper internal antenna is not used. The terminal 101 may be adjusted so as to have good characteristics only when not folded, and it is not necessary to adjust the mobile phone terminal 101 so as to have good characteristics when folded.
[0081]
  Similarly, when the mobile phone terminal 101 is folded, the lower internal antenna is used, and when the mobile phone terminal 101 is not folded, the lower internal antenna is not used. Therefore, it is only necessary to adjust the cellular phone terminal 101 so as to have good characteristics only when the cellular phone terminal 101 is folded, and it is not necessary to adjust the cellular phone terminal 101 so as to have favorable characteristics when not folded.
[0082]
  Therefore, the upper internal antenna and the lower internal antenna do not need to be advancedly adjusted as in the prior art, and the degree of freedom in designing them is improved, and each antenna can be reduced in size and thickness. It becomes like this. Therefore, an antenna having excellent performance can be provided even if it is not a high-grade antenna.
[0083]
  In the present embodiment, the mobile phone terminal 101 has been described as being used in a frequency band of 800 MHz, but may be used in other frequency bands such as a 1.5 GHz band. .
[0084]
  In the present embodiment, the upper internal antenna is incorporated in the upper housing 102 and the lower internal antenna is incorporated in the lower housing 103. However, the present invention is not limited to this. Two built-in antennas may be built in the upper housing 102, or two built-in antennas may be built in the lower housing 103. In short, one of the built-in antennas only needs to be used when the mobile phone terminal is folded, and the other antenna only needs to be used when the mobile phone terminal is not folded.
[0085]
  In the present embodiment, the case has been described in which the lower internal antenna is not used when the mobile phone terminal 101 is not folded, and the upper internal antenna is not used when the mobile phone terminal 101 is folded. However, the present invention is not limited to this, and the degradation amount of the characteristics of the upper internal antenna when the mobile phone terminal 101 is folded relative to the characteristics of the upper internal antenna when the mobile phone terminal 101 is not folded is a multiple wave propagation environment. If the signal level fluctuation is less than the instantaneous signal level fluctuation due to fading, the reception of diversity between the upper internal antenna and the lower internal antenna is performed, so that the fading of the instantaneous signal level is relieved by fading and communication interruption is avoided. It is natural that we can expect that. Further, the deterioration amount of the characteristics of the lower internal antenna when the mobile phone terminal 101 is not folded with respect to the characteristics of the lower internal antenna when the mobile phone terminal 101 is folded is an instantaneous signal due to fading in the multiwave propagation environment. If it is smaller than the level fluctuation, diversity reception between the upper internal antenna and the lower internal antenna can be expected to relieve the instantaneous signal level drop due to fading and avoid communication interruption. Of course.
[0086]
  As described above, when the mobile phone terminal 101 is not folded, diversity reception is performed with the upper internal antenna as the main antenna and the lower internal antenna as the sub-antenna. When the mobile phone terminal 101 is folded, the upper internal antenna is used. Diversity reception using the antenna as a sub-antenna and the lower internal antenna as the main antenna can also be performed. Also, when the mobile phone terminal 101 is not folded, diversity transmission is performed with the upper internal antenna as the main antenna and the lower internal antenna as the sub-antenna. When the mobile phone terminal 101 is folded, the upper internal antenna is Diversity transmission may be performed using the sub-antenna and the lower internal antenna as the main antenna.
[0087]
  Note that the main antenna means an antenna that is normally fed, and the sub-antenna means an antenna that is fed when the reception state of the main antenna is lowered.
[0088]
  In addition, diversity transmission according to the present embodiment means that an antenna selected as a main antenna at the time of diversity reception is used as a transmission antenna, that is, a transmission antenna at the time of transmission. Therefore, the diversity transmission according to the present embodiment can be applied even when the transmission frequency and the reception frequency are different.
[0089]
  In addition, when the cellular phone terminal 101 is folded in this way, when receiving, diversity reception is performed using the upper internal antenna having deteriorated characteristics and the lower internal antenna having good characteristics when transmitting. Causes the upper internal antenna to function as a parasitic element and uses the lower internal antenna to strongly radiate a transmission wave in a predetermined direction. When the cellular phone terminal 101 is not folded, when receiving, diversity reception is performed using the upper internal antenna having good characteristics and the lower internal antenna having degraded characteristics, and when transmitting, the upper internal antenna is used. Of the antenna and the lower internal antenna, the antenna with the higher reception level can be used, and the antenna with the lower reception level can function as a parasitic element.
[0090]
  In addition, when the mobile phone terminal 101 is folded, when receiving, diversity reception is performed by the upper internal antenna and the lower internal antenna, and when transmitting, between the upper internal antenna and the lower internal antenna. The antenna with the higher reception level is used, and the antenna with the lower reception level is caused to function as a parasitic element. And when the cellular phone terminal 101 is not folded, when receiving, diversity reception is performed with the upper internal antenna and the lower internal antenna, and when transmitting, the lower internal antenna functions as a parasitic element, The upper internal antenna can also be used.
[0091]
  Further, when the cellular phone terminal 101 is folded, when receiving, diversity reception is performed with the upper internal antenna and the lower internal antenna, and when transmitting, the upper internal antenna functions as a parasitic element, Use the lower internal antenna. When the mobile phone terminal 101 is not folded, when receiving, diversity reception is performed by the upper internal antenna and the lower internal antenna, and when transmitting, the upper internal antenna is used, and the lower internal antenna is used. Can also function as a parasitic element.
[0092]
  In addition, when the mobile phone terminal 101 is folded, when receiving, diversity reception is performed by the upper internal antenna and the lower internal antenna, and when transmitting, between the upper internal antenna and the lower internal antenna. The antenna with the higher reception level is used, and the antenna with the lower reception level is caused to function as a parasitic element. When the mobile phone terminal 101 is not folded, when receiving, diversity reception is performed by the upper internal antenna and the lower internal antenna, and when transmitting, between the upper internal antenna and the lower internal antenna. The antenna with the higher reception level can be used, and the antenna with the lower reception level can function as a parasitic element.
[0093]
  (No.2Embodiment)
  Next2The embodiment will be described.
[0094]
  FIG. 2 shows a mobile phone terminal 101 according to the present embodiment. The configuration of the mobile phone terminal 101 of the present embodiment is1This is the same as the embodiment.
[0095]
  First1The difference from the embodiment is2The mobile phone terminal 101 according to the embodiment is a dual band device that can be used in two frequency bands of 800 MHz band and 1.5 GHz band.
[0096]
  Other than that1This is the same as the embodiment.
[0097]
  Next, the operation of this embodiment will be described.1The difference from the embodiment will be mainly described.
[0098]
  First2The mobile phone terminal 101 according to the embodiment performs wireless communication with a base station (not shown) using a frequency band of 800 MHz and communicates with a base station using a frequency band of 1.5 GHz. Wireless communication with
[0099]
  That is, when the cellular phone terminal 101 is not folded, the upper internal antenna is used in both the 800 MHz band and the 1.5 GHz band. That is, the upper internal antenna is fed. On the other hand, when the cellular phone terminal 101 is folded, the lower internal antenna is used in both the 800 Hz band and the 1.5 GHz band. That is, the lower internal antenna is fed.
[0100]
  Thus, when using two frequency bands of 800 MHz band and 1.5 GHz band,1The same effect as in the embodiment can be obtained.
[0101]
  Furthermore, since each of the upper internal antenna and the lower internal antenna is used in two frequency bands, the circuit scale of the mobile phone terminal 101 can be reduced compared to using each internal antenna only in one frequency band. I can expect.
[0102]
  (No.3Embodiment)
  Next3The embodiment will be described.
[0103]
  FIG. 2 shows a mobile phone terminal 101 according to the present embodiment. The configuration of the mobile phone terminal 101 of the present embodiment is1This is the same as the embodiment.
[0104]
  FIG. 4 shows a specific example of the upper internal antenna.
[0105]
  4A is an example of the upper internal antenna when the mobile phone terminal 101 is not folded, and FIG. 4B is an upper internal antenna when the mobile phone terminal 101 is folded. It is an example of an antenna.
[0106]
  When the cellular phone terminal 101 is not folded, the upper internal antenna includes a ground plane 301a, an antenna element 302, a power feeding unit 303, and a short circuit unit 304. That is, in the upper internal antenna shown in FIG. 4A, a short-circuit portion 304 is formed at the end of the ground plate 301a having a length of 140 mm and a width of 40 mm. The antenna element is supported by the short-circuit portion 304. 302 is arranged at a position 5 mm above the base plate 301a. One part of the power feeding part 303 for feeding power to the antenna element 302 is connected to the central part of the ground plane 301a in the part of the antenna element 302 on the side where the short-circuit part 304 is formed. Are connected to the ground plane 301a. In addition, the antenna element 302 has a slit in the width direction at an intermediate portion between the short-circuit portion 304 and the short-circuit portion 304 and the power-feed portion 303 on the side to which the power-feed portion 303 is connected. There are two slits. As described above, the upper internal antenna is obtained by adjusting the positions of the slit, the short-circuit portion 304, and the power feeding portion 303 so that matching can be achieved in the 800 MHz band.
[0107]
  When the mobile phone terminal 101 is folded, the upper internal antenna includes a ground plane 301b, an antenna element 302, a power feeding unit 303, and a short circuit unit 304. That is, the ground plane 301b of the lower internal antenna shown in FIG. 4B has a length of 70 mm and a width of 40 mm, and is shorter than the ground plane 301a of FIG. This is because when the mobile phone terminal 101 is folded, the upper ground plate 107 and the lower ground plate 108 are folded. The other parts are the same as those in FIG.
[0108]
  Thus, the upper internal antenna is formed as an inverted F antenna in any case.
[0109]
  When the mobile phone terminal 101 is not folded, the ground plate 301a is electrically connected to the upper ground plate 107 and the lower ground plate 108 of FIG. Is formed. When the mobile phone terminal 101 is folded, as shown in FIG. 4B, the ground plate 301b is a state in which the upper ground plate 107 and the lower ground plate 108 are folded via the hinge portion 104. It is.
[0110]
  8 and 9 show examples of the lower internal antenna.
[0111]
  FIG. 8 shows an example of the lower internal antenna when the mobile phone terminal 101 is not folded. 8A is a perspective view of the lower internal antenna when the cellular phone terminal 101 is not folded, and FIG. 8B is a diagram illustrating the antenna element 312 portion of FIG. FIG. 8C is a view of the antenna element 312 viewed from the direction indicated by Q of FIG. 8A, that is, from above the ground plane 311a. is there.
[0112]
  When the cellular phone terminal 101 is not folded, as shown in FIG. 8A, the lower internal antenna is constituted by a ground ground plane 311 a and an antenna element 312. That is, a power feeding unit 313 is provided at an end portion in the length direction of the ground plate 311 a having a length of 100 mm and a width of 400 mm, and the antenna element 312 is connected to the power feeding unit 313. The antenna element 312 is a helical antenna that is connected to the power feeding unit 313 and has a bent spiral shape as shown in FIGS. 8B and 8C.
[0113]
  FIG. 9 is an example of the lower internal antenna when the mobile phone terminal 101 is folded. 9A is a perspective view of the lower internal antenna when the cellular phone terminal 101 is folded, and FIG. 9B shows the antenna element 312 in FIG. FIG. 9C is a view of the antenna element 312 as viewed from the direction indicated by Q of FIG. 9A, that is, from above the ground plane 311b. is there.
[0114]
  As shown in FIG. 9A, the lower internal antenna includes a ground plane 311 b and an antenna element 312. The base plate 311b has a half length compared to the base plate 311a of FIG.
[0115]
  Thus, the lower internal antenna is formed as a helical antenna in any case.
[0116]
  When the cellular phone terminal 101 is not folded, as shown in FIG. 8A, the ground plane 311a is electrically connected to the upper ground plane 107 and the lower ground plane 108 of FIG. Is formed. Further, when the mobile phone terminal 101 is folded, as shown in FIG. 9A, the ground plane 311b is a state in which the upper ground plane 107 and the lower ground plane 108 are folded via the hinge portion 104. It is.
[0117]
  Next, the operation of this embodiment will be described.
[0118]
  In the present embodiment, the upper ground plate 107 and the lower ground plate 108 are electrically connected to each other. When the mobile phone terminal 101 is not folded, the ground plate 301a and FIG. 8 shown in FIG. A ground plane 311a shown in FIG.
[0119]
  On the other hand, when the cellular phone terminal 101 is folded, as shown in FIG. 4B, the ground plate 301b is a state in which the upper ground plate 107 and the lower ground plate 108 are folded via the hinge portion 104. It is. When the mobile phone terminal 101 is folded, as shown in FIG. 8B, the ground plane 311b is a state in which the upper ground plane 107 and the lower ground plane 108 are folded via the hinge portion 104. It is.
[0120]
  In the 800 MHz band, the upper internal antenna is used when the mobile phone terminal 101 is not folded, and the lower internal antenna is used when the mobile phone terminal 101 is folded.
[0121]
  With respect to such an upper internal antenna, impedance characteristics and VSWR were obtained by experiments. FIG. 5 shows a Smith chart of impedance characteristics of the upper internal antenna when the mobile phone terminal 101 is not folded and the antenna element 302 is viewed from the power feeding unit 303. FIG. 6 also shows the VSWR (voltage standing wave ratio). As shown in FIG. 5, the upper internal antenna has a good impedance characteristic around 900 MHz. Further, as shown in FIG. 6, the upper internal antenna has a bandwidth at which VSWR is 2 or less is 109 MHz. That is, VSWR was 2 or less in the band from 838 MHz to 947 MHz. Therefore, the center frequency of the band where VSWR is 2 or less is 893 MHz, and the resonance frequency at which VSWR is minimum is 900 MHz.
[0122]
  FIG. 7 shows a Smith chart of impedance characteristics of the upper internal antenna when the mobile phone terminal 101 is folded and the antenna element 302 is viewed from the power feeding unit 303. In the Smith chart of FIG. 7, there is no frequency band having good impedance characteristics at frequencies from 800 MHz to 1 GHz.
[0123]
  In other words, the upper internal antenna has better characteristics in the 800 MHz band when the cellular phone terminal 101 is not folded than when the cellular phone terminal 101 is folded.
[0124]
  Thus, the upper internal antenna is adjusted to have better characteristics when the cellular phone terminal 101 is not folded than when the cellular phone terminal 101 is folded. Therefore, since it is not necessary to adjust so as to have good characteristics in both states unlike the conventional upper internal antenna, the thickness can be made thinner than the conventional upper internal antenna.
[0125]
  As for the lower internal antenna, when the mobile phone terminal 101 is not folded, the VSWR in which the antenna element 312 is viewed from the power feeding unit 313 is 4.5 at 810 MHz and 4 at 960 MHz. .6. On the other hand, when the cellular phone terminal 101 is folded, the VSWR in which the antenna element 312 is viewed from the power feeding unit 313 is 3.0 at a frequency of 810 MHz and 3.2 at a frequency of 960 MHz. That is, the lower internal antenna has better characteristics when the cellular phone terminal 101 is folded than when it is not folded.
[0126]
  Therefore, when the mobile phone terminal 101 is not folded, the upper internal antenna is used. That is, the upper internal antenna is fed. On the other hand, when the cellular phone terminal 101 is folded, the lower internal antenna is used. That is, the lower internal antenna is fed. In this way, when the cellular phone terminal 101 is folded, the lower internal antenna is used, and when the cellular phone terminal 101 is not folded, the upper internal antenna is used, thereby reducing the thickness of the cellular phone terminal 101. I can do it.
[0127]
  The first3In the embodiment of the1As in the above embodiment, when the upper internal antenna is not used, the upper internal antenna functions as a parasitic element for the lower internal antenna, and the upper internal antenna has a predetermined directivity and wideband frequency characteristics. If arranged so as to have directivity, directivity can be formed so as to radiate a transmission wave strongly in a predetermined direction, and at the same time, broadband characteristics can be provided. Similarly, when the lower internal antenna is not used, the lower internal antenna functions as a parasitic element for the upper internal antenna so that the lower internal antenna has a predetermined directivity and wideband frequency characteristics. If it arrange | positions, directivity can be formed so that a transmission wave may be radiated | emitted strongly to a predetermined direction, and it can have a broadband characteristic simultaneously.
[0128]
  Further, by filling the space between the antenna element 302 and the ground plane 301a of the upper internal antenna of FIG. 4 with a dielectric, the strength of the upper internal antenna can be increased, and the upper internal antenna can be increased due to the wavelength shortening effect by the dielectric. Can be further reduced in size.
[0129]
  Similarly, by filling the antenna element 312 and the ground plane 311a of the lower internal antenna of FIGS. 8 and 9 with a dielectric, the strength of the lower internal antenna can be increased and the wavelength can be shortened by the dielectric. The lower internal antenna can be further downsized due to the effect.
[0130]
  Note that the upper ground plane 107 and the lower ground plane 108 of the present embodiment are formed by electrically connecting a part of the substrate 1202 and the shield case 1206 in the same manner as the built-in antenna described in the related art. I can do it.
[0131]
  Further, as shown in FIG. 10, a part of the upper casing 102 of the mobile phone terminal 101 is formed using a conductive material such as a metal part 321 and a part of the lower casing 103 is formed. It can also be formed using a conductive material such as the metal portion 322. That is, the metal portion 321 of the upper housing 102 is formed of a conductive material such as metal or magnesium, and the other portions are formed of resin. Similarly, the metal portion 322 of the lower housing 103 is formed of a conductive material such as metal or magnesium, and the other portions are formed of resin. Then, the upper ground plate 107 and the metal portion 321 are electrically connected, and the lower ground plate 108 and the metal portion 322 are electrically connected, so that the metal portion 321 and the metal portion 322 can also be used as the ground plate. I can do it.
[0132]
  By doing so, the area that functions as the ground plane increases and the maximum value of the current density decreases, so that the SAR (Specific Absorption Ratio) can be further reduced.
[0133]
  Note that the SAR indicates the degree of influence of electromagnetic waves radiated from the mobile phone terminal 101 on human tissue. That is, this represents the amount of high-frequency current induced in the pseudo human body by the radiation of electromagnetic waves radiated from the mobile phone terminal 101, and the thermal energy generated by this current being absorbed per unit tissue. Therefore, the SAR can be further reduced by reducing the maximum value of the current flowing on the ground plane.
[0134]
  FIG. 11 shows a detailed configuration of the metal portions 321 and 322. FIG. 11A is a front view when the cellular phone terminal 101 is not folded, and FIG. 11B is a side view thereof. FIG. 11C is a side view when the cellular phone terminal 101 is folded. When the cellular phone terminal 101 is folded, the lower internal antenna element 106 is formed with a metal portion 321 so as to be away from the metal portion 321. Therefore, when the cellular phone terminal 101 is folded, the metal portion 321 is formed so that the metal portion 321 does not overlap the lower internal antenna element 106. Thus, when the lower antenna element 106 is configured by a linear antenna such as a helical antenna, the lower built-in antenna can be made to have a wider band by separating the lower antenna element 106 and the ground plane.
[0135]
  Further, a metal portion 321 is formed so that there is no metal portion above the upper end of the upper internal antenna 105. By arranging the upper internal antenna element 105 at the end portion of the ground plane, impedance matching can be easily realized, and broadband characteristics can be realized.
[0136]
  In this way, the strength of the mobile phone terminal 101 can be improved by designing the metal portions 321 and 322 of the upper housing 102 and the lower housing 103 so that the antenna characteristics are the best, and the antenna can be downsized. It is possible to realize a low profile.
[0137]
  In the present embodiment, the upper ground plate 107 of the upper internal antenna is provided. However, the present invention is not limited to this, and the upper ground plate 107 can be shared by the conductive portion of the display 109. For example, when the display 109 has a display body, a frame provided around the display body, and a reflection plate provided on the back side of the image display surface of the display body, the reflection plate is made of a conductive material. The upper base plate 107 can also be used as this reflector. Alternatively, the frame can be formed of a conductive material, and the upper base plate 107 can also be used as the frame. In addition, the upper ground plate 107 may be shared by all or part of the reflector, the frame, and the upper housing. In this way, it is not necessary to provide the upper base plate 107 specially, so that the height of the upper internal antenna can be further reduced.
[0138]
  As described above, according to the present embodiment, each of the upper internal antenna and the lower internal antenna is used in either the case where the mobile phone terminal is folded or the case where it is not folded. The antenna can be made thinner. Therefore, the thicknesses of the upper internal antenna and the lower internal antenna areEnd 1The thickness can be made thinner than the thickness determined by components other than the 01 upper internal antenna and the lower internal antenna. As a result, the mobile phone terminal 101 can be made thinner.
[0139]
  (No.4Embodiment)
  Next4The embodiment will be described.
[0140]
  FIG. 2 shows a mobile phone terminal 101 according to the present embodiment. The configuration of the mobile phone terminal 101 of the present embodiment is1This is the same as the embodiment.
[0141]
  First1The difference from the embodiment is4The mobile phone terminal 101 according to the embodiment is a dual band device that can be used in two frequency bands of 800 MHz band and 1.5 GHz band.
[0142]
  FIG. 12 shows a specific example of the upper internal antenna.
[0143]
  The upper internal antenna includes a ground plane 401, an antenna element 402, a power feeding unit 403, a first short circuit unit 404 a, a second short circuit unit 404 b, and a switch circuit 405.
[0144]
  That is, one of the first short-circuit portions 404 a is connected to the ground plane 401, and one of the second short-circuit portions 404 b is connected to the ground plane 401 via the switch circuit 405. And the antenna element 402 is connected to the other of the 1st short circuit part 404a and the other of the 2nd short circuit part 404b. In addition, one of the power feeding units 403 is connected to the antenna element 402, and the other is connected to the ground plane 401. One terminal of the switch circuit 405 is connected to the ground plane 401, and the reactance load 406 is connected to the other terminal.
[0145]
  FIG. 13 shows an example of the lower internal antenna.
[0146]
  In the lower internal antenna, an antenna element 412a as a helical antenna having a bent spiral shape for 800 MHz band is connected to the ground plane 411 via a power feeding part 413a for 800 MHz band, and the ground plane 411 is for 1.5 GHz band. An antenna element 412b serving as a helical antenna having a bent spiral shape for a 1.5 GHz band is connected via a power feeding portion 413b. That is, the lower internal antenna of FIG. 13 has a configuration in which an antenna element for 1.5 GHz band is added to the lower internal antenna shown in FIG.
[0147]
  Thus, the lower internal antenna is formed as a helical antenna having a bent spiral shape in any case.
[0148]
  The lower internal antenna may be an antenna as shown in FIG. The antenna shown in FIG. 14 is different from the antenna shown in FIG. 13 except that a portion corresponding to the antenna elements 412a and 412b in FIG. 13 has a spiral shape that is not bent.
[0149]
  If the mobile phone terminal 101 is not folded,3Similarly to the first embodiment, the ground plane 411 is formed by electrically connecting the upper ground plane 107 and the lower ground plane 108 of FIG. When the mobile phone terminal 101 is folded, the ground plane 411 is in a state where the upper ground plane 107 and the lower ground plane 108 are folded via the hinge portion 104.
[0150]
  Next, the operation of this embodiment will be described.
[0151]
  In the present embodiment, the upper ground plate 107 and the lower ground plate 108 are electrically connected to each other. When the mobile phone terminal 101 is not folded, the ground plate 401 shown in FIG. 12 and the ground plate 411 shown in FIG. Form. On the other hand, when the mobile phone terminal 101 is folded, the ground plate 401 is in a state where the upper ground plate 107 and the lower ground plate 108 are folded via the hinge portion 104 as shown in FIG. When the mobile phone terminal 101 is folded, as shown in FIG. 13, the ground plane 411 is in a state where the upper ground plane 107 and the lower ground plane 108 are folded via the hinge portion 104.
[0152]
  In the 800 MHz band, the upper internal antenna is used when the mobile phone terminal 101 is not folded, and the lower internal antenna is used when the mobile phone terminal 101 is folded.
[0153]
  On the other hand, in the 1.5 GHz band, the upper internal antenna is used when the mobile phone terminal 101 is folded, and the lower internal antenna is used when the mobile phone terminal 101 is not folded.
[0154]
  That is, when using in the 800 MHz band, the switch of the upper internal antenna is switched to the reactance load 406 side, and the upper internal antenna of FIG. 12 is used as the inverted F antenna. On the other hand, when used in the 1.5 GHz band, the switch of the upper internal antenna is switched to the side connected to the ground plane 401, and the second short circuit portion 404 b is short-circuited to the ground plane 401. In this way, the upper internal antenna of FIG. 12 is used as a two-point short-circuited inverted F antenna.
[0155]
  For the lower internal antenna, when the 800 MHz band is used, the antenna element 412a is used by supplying power to the power supply unit 413a. In addition, when the 1.5 GHz band is used, the antenna element 412b is used by supplying power to the power supply unit 413b.
[0156]
  As described above, the upper internal antenna has better characteristics when the cellular phone terminal 101 is not folded in the frequency band of 800 MHz, and the cellular phone terminal 101 is folded in the 1.5 GHz band. It has better characteristics. The lower internal antenna has better characteristics in the 800 MHz band when the cellular phone terminal 101 is folded, and in the 1.5 GHz band, the cellular phone terminal 101 is not folded. Have better properties.
[0157]
  When the mobile phone terminal 101 is not folded, the one shown in FIG. 12 is used as the upper internal antenna in the 800 MHz band. In this case, the base plate 401 is formed by electrically connecting the upper base plate 107 and the lower base plate 108. Therefore, since the base plate 401 can be made sufficiently large, the characteristics can be improved. However, when the base plate 401 is formed by connecting the upper base plate 107 and the lower base plate 108, the upper built-in antenna is narrowed because the base plate 401 is too large in the 1.5 GHz band. Therefore, in the 1.5 GHz band, when the mobile phone terminal 101 is not folded, the upper internal antenna is not used, and only when the mobile phone terminal 101 is folded, the upper internal antenna is used. did.
[0158]
  In this way, since the better condition of the ground plane at each frequency can be selected, it is possible to realize a wider band and higher efficiency.
[0159]
  (No.5Embodiment)
  15 and FIG.5The mobile phone terminal 501 of the embodiment is shown. The mobile phone terminal 501 of this embodiment is a foldable mobile phone terminal as in the above embodiments. FIG. 15A is a front view when the cellular phone terminal 501 is folded, and FIG. 15B is a side view thereof. FIG. 16A is a front view when the cellular phone terminal 501 is not folded, and FIG. 16B is a side view thereof.
[0160]
  In the mobile phone terminal 501, the upper housing 102 and the lower housing 103 are coupled via a hinge portion 104, and the upper housing 102 and the lower housing 103 can be folded via the hinge portion 104. It is configured.
[0161]
  The upper housing 102 incorporates a display 109, and has a sound hole portion 502 for outputting sound. The upper housing 102 on the back side of the display 109 is made of metal such as magnesium. Thus, the housing antenna 102a is configured. In this case, the housing antenna 102a and the lower ground plate 108 are electrically separated, and the lower ground plate 108 functions as the ground plate of the housing antenna 102a.
[0162]
  The housing antenna 102a is adjusted to have good characteristics when the cellular phone terminal 501 is not folded.
[0163]
  Further, the lower casing 103 has a key 110 built therein, and a lower base plate 108 and a battery 503 are built in the back side of the key 110, and on the opposite side of the key 110 from the hinge portion 104, A microphone 504 for inputting voice is incorporated. A boom antenna 505 is disposed on the surface of the hinge portion 104 opposite to the key 110. The lower ground plane 108 also functions as a ground plane for the boom antenna.
[0164]
  The boom antenna 505 is adjusted to have good characteristics when the cellular phone terminal 501 is folded.
[0165]
  Next, the operation of this embodiment will be described.
[0166]
  The cellular phone terminal 501 of this embodiment performs wireless communication with a base station (not shown) using a frequency band of 800 MHz.
[0167]
  When the cellular phone terminal 501 is not folded, the housing antenna 102a is used. That is, the housing antenna 102a is fed. On the other hand, when the mobile phone terminal 501 is folded, the boom antenna 505 is used. That is, the boom antenna 505 is fed.
[0168]
  When the mobile phone terminal 501 is used without being folded, the user of the mobile phone terminal 501 usually makes a call while holding the lower casing 103 by hand. At this time, the upper housing 102 is not held by a user's hand or the like. Therefore, when the cellular phone terminal 501 is used in a state where the cellular phone terminal 501 is not folded, the housing antenna 102a is less likely to decrease in gain due to the influence of the human body than the boom antenna 505. Therefore, in this case, the use of the housing antenna 102a can further suppress a decrease in gain due to the influence of the human body.
[0169]
  On the other hand, when the mobile phone terminal 501 is used in a folded state, the user of the mobile phone terminal 501 puts the mobile phone terminal 501 in a breast pocket or puts it on a desk or table. In this case, since the cellular phone terminal 501 is folded, the housing antenna 102a is not used and the boom antenna 505 is used.
[0170]
  When the cellular phone terminal 501 is not folded, the casing antenna 102a is used. When the cellular phone terminal 501 is folded, the casing antenna 102a is not used. The mobile phone terminal 501 may be adjusted so as to have good characteristics only when not folded, and it is not necessary to adjust the mobile phone terminal 501 so as to have good characteristics when folded.
[0171]
  Similarly, when the mobile phone terminal 501 is folded, the boom antenna 505 is used. When the mobile phone terminal 501 is not folded, the boom antenna 505 is not used. It is only necessary to adjust the terminal 501 so as to have good characteristics only when the terminal 501 is folded, and it is not necessary to adjust the mobile phone terminal 501 so as to have good characteristics when not folded.
[0172]
  Accordingly, the housing antenna 102a and the boom antenna 505 do not need to be subjected to advanced adjustment as in the past, and the degree of freedom in designing them is improved, and each antenna can be reduced in size and thickness. It becomes like this. Therefore, an antenna having excellent performance can be provided even if it is not a high-grade antenna. Further, since the housing antenna 102a is configured such that a part of the upper housing 102 is made of a metal such as magnesium so that the housing function and the antenna function are combined, There is no need to provide an antenna element, and the upper casing 102 can be reduced in height accordingly.
[0173]
  Further, the display 109 side can be formed of metal, and this portion can also function as an antenna element. In this way, there is an advantage that the strength of the display 109 can be enhanced by forming the display 109 side with a metal so as to also serve as an antenna element. In addition, compared to the case where the display 109 side is formed of metal and also serves as an antenna element, the upper housing 102 on the back side of the display 109 is formed of metal such as magnesium as in the present embodiment, By combining the functions of the housing and the antenna as the housing antenna 102a, the distance between the housing antenna 102a and the human ear is further increased. Accordingly, since the current flowing through the ear becomes smaller, the influence on the human body can be further reduced.
[0174]
  The back surface of the upper housing 102 is formed of a metal such as magnesium as the housing antenna 102a, the display 109 portion is formed of resin, and the holder (frame) portion of the display 109 is formed of metal. The mechanical strength of the terminal 501 can be increased and the mechanical stability can be increased.
[0175]
  Although the mobile phone terminal 501 of the present embodiment has been described as performing communication with a base station (not shown) using the 800 MHz band, it is used in two frequency bands of 800 MHz and 1.5 GHz. It doesn't matter.
[0176]
  FIGS. 17A and 17B show housing antennas 102b and 102c that can be used in two frequency bands as described above. The housing antenna 102b in FIG. 17A has a configuration in which a slot 506 having a length of approximately λ / 2 is provided when the wavelength in the 1.5 GHz band is λ. 17B has a configuration in which a slit 507 having a length of approximately λ / 4 is provided when the wavelength in the 1.5 GHz band is λ.
[0177]
  As described above, the housing antenna itself is configured to be usable in two frequency bands as shown by the housing antennas 102b and 102c, and two frequency bands are provided by the matching circuit provided in the wireless circuit of the mobile phone terminal 501. Even if switching is performed, the wireless circuit and the housing antennas 102b and 102c can be matched.
[0178]
  In the present embodiment, the mobile phone terminal 501 is described as being used in the 800 MHz frequency band, but may be used in other frequency bands such as the 1.5 GHz band. .
[0179]
  Furthermore, although the case where the housing antenna of the present embodiment is used in two frequency bands of 800 MHz band and 1.5 GHz band has been described, the case is used in two frequency bands other than the 800 MHz band and 1.5 GHz band. Even so, the present embodiment can be applied.
[0180]
  Note that in this embodiment, when the mobile phone terminal 501 is not folded, the boom antenna 505 is not used, and when the mobile phone terminal 501 is folded, the case antenna 102a is not used. However, the present invention is not limited to this, and the characteristic difference of the boom antenna 505 when the mobile phone terminal 501 is not folded is different from the characteristic of the housing antenna 102a when the mobile phone terminal 501 is not folded in the multiwave propagation environment. If the fluctuation is smaller than the instantaneous signal level fluctuation due to fading, the reception of diversity between the housing antenna 102a and the boom antenna 505 can be performed to relieve the instantaneous signal level drop by fading and to avoid the interruption of communication. It is natural to expect. Further, the characteristic difference of the housing antenna 102a when the cellular phone terminal 501 is folded with respect to the characteristics of the boom antenna 505 when the cellular phone terminal 501 is folded is based on the instantaneous signal level fluctuation due to fading in the multi-wave propagation environment. In the case of small size, it is natural that the reception of diversity between the housing antenna 102a and the boom antenna 505 can be expected to relieve the instantaneous signal level drop due to fading and avoid the interruption of communication. It is.
[0181]
  As described above, when the cellular phone terminal 501 is not folded, diversity reception is performed with the casing antenna 102a as the main antenna and the boom antenna 505 as the sub-antenna, and the cellular phone terminal 501 is folded. Diversity reception using the antenna 102a as a sub antenna and the boom antenna 505 as a main antenna can also be performed. When the mobile phone terminal 501 is not folded, diversity transmission is performed with the housing antenna 102a as the main antenna and the boom antenna 505 as the sub-antenna, and when the mobile phone terminal 501 is folded, the housing antenna 102a. Diversity transmission may be performed using the sub antenna as a sub antenna and the boom antenna 505 as a main antenna. For the main antenna and sub antennaReference exampleThis is the same as described in.
[0182]
  (No.6Embodiment)
  Next6The embodiment will be described. FIG. 18 is a block diagram of the communication device 1001 according to this embodiment. The communication device 1001 is a mobile phone terminal, for example. In FIG. 18, the transmission signal output from the transmission circuit is transmitted to the mixer 1003 via the filter 1002. The transmission signal input to the mixer 1003 is up-converted by the local signal from the oscillator 1004 and transmitted to the antenna 1009a or 1009b via the transmission filter 1005, the amplifier 1006, the transmission filter 1007, and the switch 1008. A reception signal received from the antenna 1009 a or 1009 b is input to the mixer 1013 through the switch 1008, the reception filter 1010, the amplifier 1011, and the reception filter 1012. The received signal input to the mixer 1013 is down-converted by the local signal from the oscillator 1004 and transmitted to the receiving circuit via the filter 1014.
[0183]
  Here, by using the upper internal antenna and the lower internal antenna described in each of the above embodiments as the antennas 1009a and 1009b, a low-profile communication device can be realized. Further, by using the housing antenna and the boom antenna as the antennas 1009a and 1009b, respectively, a low-profile communication device can be realized.
[0184]
  In this embodiment, the transmission / reception signals are connected to the antennas 1009a and 1009b and separated by the switch 1008. However, this may be a duplexer.
[0185]
  That is, the antenna structure of the present invention, a transmission circuit that outputs a transmission signal to the first antenna or the second antenna, and a reception signal received by the first antenna or the second antenna are input. A communication device including a receiving circuit is also included in the present invention.
[0186]
  In this way, by placing multiple antennas that exhibit good characteristics when the mobile phone terminal is folded and used without being folded, it is used when folded with one antenna and without being folded. In comparison with the case where the characteristics are satisfied in both cases, the size of the antenna can be reduced and the thickness can be reduced, and a thin cellular phone terminal can be provided.
[0187]
  Note that the upper internal antenna of this embodiment is an example of the first antenna of the present invention, and the lower internal antenna of this embodiment is an example of the second antenna of the present invention. The upper housing is an example of the first housing portion of the present invention, the lower housing of the present embodiment is an example of the second housing portion of the present invention, and the 800 MHz band of the present embodiment is This is an example of the low frequency band of the present invention, and the 1.5 GHz band of the present embodiment is an example of the high frequency band of the present invention.
[0188]
【The invention's effect】
  As is apparent from the above description, the present invention can make a foldable mobile phone terminal thinner.Portable wireless terminalCan be provided.
[Brief description of the drawings]
FIG. 1 (a) of the present inventionReference exampleView of mobile phone terminal in Japan
  (B) of the present inventionReference exampleSide view of mobile phone terminal
FIG. 2 (a) First of the present invention1~3Front view of mobile phone terminal in the embodiment
  (B) The present invention1~3Side view of mobile phone terminal in the embodiment
FIG. 3 (a) First of the present invention1The figure explaining the case where the cellular phone terminal in the embodiment is folded and stored in the breast pocket
  (B) The present invention1The figure explaining the case where the cellular phone terminal in the embodiment is folded and placed on an iron table
FIG. 4 (a) First of the present invention3The figure which shows the specific example of the upper side internal antenna in case the mobile telephone terminal in embodiment of this is not folded
  (B) The present invention3The figure which shows the specific example of the upper side internal antenna at the time of folding the form telephone terminal in embodiment of this
FIG. 5 shows the first of the present invention.3FIG. 4 shows a Smith chart of the upper internal antenna shown in FIG.
FIG. 6 shows the first of the present invention.3The frequency characteristic of VSWR of the upper side internal antenna shown to (a) of FIG. 4 in embodiment of FIG.
FIG. 7 shows the first of the present invention.3The Smith chart of the upper side internal antenna shown in FIG.4 (b) in embodiment of FIG.
FIG. 8 (a) First of the present invention3The perspective view of the lower internal antenna when the cellular phone terminal in the embodiment is not folded
  (B) The present invention3The figure which looked at the part of the antenna element of the lower side built-in antenna from the direction of P when the cellular phone terminal in the embodiment is not folded
  (C) The present invention3The figure which looked at the part of the antenna element of the lower side built-in antenna from the direction of Q when the cellular phone terminal in the embodiment is not folded
FIG. 9 (a) First of the present invention3The perspective view of the lower side built-in antenna when the cellular phone terminal is folded in the embodiment
  (B) The present invention3The figure which looked at the part of the antenna element of the lower side built-in antenna from the direction of P when the cellular phone terminal in the form of the above is folded
  (C) The present invention3The figure which looked at the part of the antenna element of the lower side built-in antenna when the cellular phone terminal in the form of this is folded from the direction of Q
FIG. 10 is a diagram showing a case where a part of the upper casing and a part of the lower casing of the mobile phone terminal in each embodiment of the present invention are formed of a conductive material.
FIG. 11A is a front view showing the configuration of the metal parts of the upper housing and the lower housing of the mobile phone terminal according to each embodiment of the present invention.
  (B) The side view which shows the structure of the metal part of the upper side housing | casing and lower side housing | casing of the mobile telephone terminal in each embodiment of this invention
  (C) The side view which shows the structure of the metal part of the upper side housing | casing of the mobile telephone terminal in each embodiment of this invention, and a lower side housing | casing
FIG. 12 shows the first of the present invention.4Showing the configuration of the upper internal antenna of the mobile phone terminal according to the embodiment
FIG. 13 shows the first of the present invention.4Showing the configuration of the lower internal antenna of the mobile phone terminal according to the embodiment
FIG. 14 shows the first of the present invention.4Showing another configuration of the lower internal antenna of the mobile phone terminal according to the embodiment
FIG. 15 (a) First of the present invention5Front view of a mobile phone terminal when the mobile phone terminal in the embodiment is folded
  (B) The present invention5Side view of a mobile phone terminal when the mobile phone terminal in the embodiment is folded
FIG. 16 (a) First of the present invention5The front view of the mobile phone terminal when the mobile phone terminal is not folded in the embodiment
  (B) The present invention5Side view of a mobile phone terminal when the mobile phone terminal is not folded in the embodiment
FIG. 17 (a) First of the present invention5The front view at the time of forming a slot in the housing antenna of the mobile phone terminal in the embodiment
  (B) The present invention5The front view at the time of forming a slit in the housing antenna of the mobile phone terminal in the embodiment
FIG. 18 shows the first of the present invention.6The block diagram which shows the structure of the communication apparatus in embodiment of
FIG. 19A is a perspective view showing a schematic configuration of a built-in antenna of a conventional mobile phone terminal.
  (B) Side view showing a schematic configuration of a built-in antenna of a conventional mobile phone terminal
FIG. 20A is a front view showing a configuration when the antenna of a conventional foldable mobile phone terminal is configured from only a built-in antenna.
  (B) A side view showing a configuration when the antenna of a conventional foldable mobile phone terminal is configured from only a built-in antenna.
[Explanation of symbols]
  101 Mobile phone terminal
  102 Upper case
  103 Lower housing
  104 Hinge part
  105 Upper built-in antenna element
  106 Lower built-in antenna element
  107 Upper side plate
  108 Lower side plate
  109 display
  110 keys
  301a Ground plate
  301b Ground plate
  302 Antenna element
  303 Power supply unit
  304 Short-circuit part
  311a Ground plate
  311b Ground plate
  312 Antenna element

Claims (5)

A portable wireless terminal that transmits and receives signals via a duplexer,
A first housing part;
A second housing part;
A first antenna disposed in the first housing portion;
A second antenna disposed in the second housing portion;
A transmission circuit;
A receiving circuit,
The first casing part and the second casing part are configured to be foldable via a hinge part,
The first and second antennas are switched by the duplexer and can be transmitted and received in a desired communication frequency band.
When receiving, when the portable wireless terminal is not folded by switching by the duplexer , the first antenna functions as a main antenna and the second antenna functions as a sub-antenna, When the portable wireless terminal is folded, the second antenna functions as a main antenna and the first antenna functions as a sub-antenna,
When transmitting, a portable radio terminal using the antenna selected as a main antenna when receiving the first antenna and the second antenna by switching with the duplexer. The first antenna is a built-in antenna built in the first housing part,
The portable wireless terminal according to claim 1, wherein the second antenna is a built-in antenna built in the second casing.   The portable wireless terminal according to claim 1, wherein the first antenna includes an antenna element and a ground plane for the antenna element. A part of the first housing part and / or the second housing part has conductivity,
The portable wireless terminal according to claim 3, wherein the conductive part is used as the ground plane.   The said 2nd housing | casing part has the closed loop-shaped protrusion part on the arrangement | positioning surface of the said hinge part, At least one part of the said protrusion part is functioning as a said 2nd antenna. The portable wireless terminal according to any one of the above.

Images