JP4413145B2 - Portable wireless terminal device - Google Patents

Description

  The present invention relates to a portable wireless terminal device that is applied to a slide-type terminal among terminal devices used for mobile communication such as a mobile phone and is suitable for improving antenna characteristics.

  In recent years, portable wireless terminal devices for mobile communication such as mobile phones (hereinafter, the terminal device is simply referred to as a terminal) have been prominently equipped with a function for connecting to mail and the Internet and a camera function. Along with this, a slide-type terminal as shown in FIG. 1 has appeared on the market from the viewpoint that the liquid crystal display unit can be enlarged and that the camera can be used conveniently.

  The sliding type terminal has a state in which the upper housing 10 is overlapped with the lower housing 20 and closed as shown in FIGS. 1A and 1C, and a bottom as shown in FIGS. 1B and 1D. The upper housing is linearly slid relative to the side housing 20, and the state can be switched between the opened state.

  The upper housing 10 includes a liquid crystal display unit 12 disposed substantially at the center main part, a receiver unit 11 disposed on the upper part, and an upper operation unit 15 disposed on the lower part. The upper operation unit 15 includes a power key, a call start key, an end key, a cancel key, a cursor operation key (decision key), and the like.

  The lower housing 20 is covered with the upper housing 10 in the closed state, and the lower operation unit 21 and the microphone unit 23 are disposed at positions exposed to the outside in the closed state. The lower operation unit 21 has various keys such as numeric / character input keys.

  In addition, since it is necessary to expose the lower operation unit 21 when inputting numbers, characters, etc., it is used in an open state. However, the receiver unit 11 and a call start are always performed regardless of the slide closed / open state. Since the key and the end call key are exposed on the surface, a call (wireless communication) can be performed both in the closed state and in the open state.

  As for the installation position of the antenna of the slide type portable wireless terminal as shown in FIG. 1, (1) the upper end of the upper (front side) casing, (2) the upper side of the lower (rear side) casing, and (3) Any one of the lower side (rear side) and the lower end of the casing is conceivable. The position where the antenna is installed is determined in consideration of the system (frequency band and transmission output) to be used, the advantages and disadvantages of each installation location, design, and the like. In particular, when there is a concern that the user's hand / finger is likely to be applied to the antenna during a call, the lower end of the lower housing is avoided because it has the highest risk. Further, considering the concern that the local average SAR (Specific Absorption Rate: power per unit time / unit mass absorbed by a specific part of the human body, hereinafter simply referred to as SAR) will increase, the upper end of the upper casing Installation is avoided. Therefore, in order to avoid these two concerns, the upper installation of the lower housing is selected as the antenna installation location.

  FIG. 2 shows a schematic view of the terminal as viewed from the side as the internal structure of the sliding portable wireless terminal as shown in FIG. In this figure, since it is not directly related to the present invention, component diagrams such as a terminal cabinet, a receiver, a microphone, a speaker, a liquid crystal display unit, a control unit, a camera, and a specific slide mechanism are omitted. In the following drawings, these members are basically omitted.

FIG. 2 shows a general basic internal structure when the slide type portable wireless terminal is closed (a) and opened (b). In this structure, the upper ground (GND) 16 mounted inside the upper housing and the lower ground 26 mounted inside the lower housing are connected to the connecting portions 17 and 27 via the relay flexible cable 19, respectively. Is electrically connected. The lower ground 26 in the lower housing is often formed of a substrate on which a transmission / reception circuit or the like is mounted, and a shield case that covers the substrate to shield it from noise or the like. Further, the upper ground 16 inside the upper casing is formed of a metal part such as a magnesium alloy in order to maintain the strength against cracking of the liquid crystal display unit or a substrate on which the control circuit of the liquid crystal display unit (12 in FIG. 1) is mounted. It is often done. FIG. 2 particularly shows the case where the antenna element 24 is installed at the upper end of the lower housing as described above. Power is supplied to the antenna element 24 from the power supply unit 25.
JP 2004-32808 A JP 2002-368526 A JP 2002-232224 A JP 2002-223107 A Japanese Patent Laid-Open No. 08-195609 JP 2004-72605 A

  3A to 3D show examples of antenna characteristic measurement results of the sliding portable wireless terminal having the internal structure of FIG. The size of the substrate, the antenna area, and the like are as shown in FIG. 3A. The relay flexible cable connecting the upper and lower grounds was assumed to have a total length of about 60 mm when extended. As shown in the figure, the antenna was a built-in antenna in which a λ / 4 monopole antenna was tilted sideways. The system used is assumed to be a 800-900 MHz band system CDMA (95B & CDMA20001X) in Japan, and the antenna matching is performed with a reception (downstream) band: 832 to 870 MHz and a transmission (upstream) band: 887 MHz to 925 MHz. The element length and the antenna matching circuit (omitted in the figure) were adjusted and combined. In particular, the matching is matched to the slide open state that is mainly used by the user in a call state.

  FIG. 3B shows a graph of the free space radiation efficiency of the antenna when the slide is closed and opened. As can be seen from this figure, the measurement frequency points are also added one point at the top and bottom (810 MHz, 960 MHz) outside the use frequency band.

  3C and 3D show the impedance characteristics of the antenna when the slide is opened and when the slide is closed, respectively. Although the impedance characteristic diagram of the antenna at the time of sliding opening (FIG. 3C) is particularly good at about VSWR = 2 on the transmission side, its radiation efficiency 41 shown in FIG. 3B is at most -5 to -6 [dB]. It is about. This is considered to be largely influenced by the upper ground that is positioned so as to cover the antenna element when the slide is opened. FIG. 9A shows the measurement result of the radiation pattern of the antenna in this state. This is a measurement result with vertical polarization. FIG. 14A shows each axis of the terminal, and FIG. 14B shows the orientation of the terminal at the time of measurement in FIG. 9A. From the measurement result of FIG. 9A, it can be seen that the radiation level on the lower ground side, that is, the terminal back side is relatively lower than the radiation level on the upper ground side, that is, the liquid crystal display unit side. This is presumably because the upper ground acts as a waveguide element for the antenna element, and this waveguide element also causes a deterioration in overall radiation efficiency.

  Conventionally, a configuration in which a short stub or a parasitic element is brought close to an antenna element has been proposed (see Patent Documents 1 to 6). These electrical roles are for causing the antenna to have a broad band by coupling the open end portion of the antenna element with the open end of the short stub or the parasitic element in proximity. The electrical length of the short stub / parasitic element is set to λ / 4 with respect to the wavelength λ of the operating frequency and is grounded to the ground. However, if sufficient electrical length cannot be secured for the terminal structure and operating frequency, the element The electrical length is adjusted by providing an adjusting element such as an inductor between the ground and the ground.

  The present invention not only realizes a wide band of impedance by using a short stub structure in a sliding portable wireless terminal device, but also couples with the upper ground, thereby adversely affecting the upper ground, which has caused efficiency degradation for the antenna element. The purpose is to reduce.

  The portable wireless terminal device according to the present invention is a portable wireless terminal device that opens and closes by sliding the upper housing relative to the lower housing, and an antenna element installed on the upper portion of the lower housing; An upper ground installed in the upper housing, a lower ground installed in the lower housing, and at least a part of the upper ground installed in a space between the upper ground and the lower ground. Alternatively, it is characterized in that it comprises a conductor member that is grounded to the lower ground, and at which the other part is at least close to the antenna element when sliding.

  With this configuration, the antenna characteristics can be improved by reducing the influence of the upper ground by the conductor member when the slide is opened.

  The conductor member may be grounded to the upper ground or the lower ground via an adjustment element. Thereby, the electrical length adjustment of the said conductor member and the matching adjustment of an antenna can be performed.

  A switching circuit that switches and uses a plurality of elements as the adjustment element may be provided. Thereby, it is possible to appropriately adjust both when the slide is open and when the slide is closed.

  A switching control unit that detects a slide open / close state is provided, and the switching circuit can be switched according to the slide open / close. Alternatively, a switching unit that detects the presence or absence of a call is provided, and the switching circuit can be switched according to the presence or absence of a call.

  Another portable wireless terminal device according to the present invention is an portable wireless terminal device that opens and closes by sliding an upper housing relative to a lower housing, and an antenna element installed on the upper portion of the lower housing. An upper ground installed in the upper housing, a lower ground installed in the lower housing, at least a part of which is grounded to the upper ground or the lower ground, and another part of which is at least a sliding open. Sometimes selectively using a conductor member arranged so as to be close to the antenna element, a plurality of adjustment elements for grounding the conductor member to the upper ground or the lower ground, and the plurality of adjustment elements And a switching means for switching as described above.

  By selectively using a plurality of adjustment elements, it is possible to appropriately adjust both when the slide is open and when the slide is closed.

  According to another aspect, the portable wireless terminal device according to the present invention opens and closes by sliding the upper casing relative to the lower casing, and wirelessly operates in both the sliding open state and the sliding closed state. In the portable wireless terminal device capable of performing communication, an antenna element installed in an upper part of the lower casing, an upper ground installed in the upper casing, and a lower side installed in the lower casing It is characterized by comprising a ground and a short stub arranged so as to improve the antenna characteristics by reducing the influence of the upper ground on the antenna element when sliding.

  According to the present invention, in the portable wireless terminal device that opens and closes by sliding the upper casing relative to the lower casing, at least a part of the portable radio terminal that is installed in the space between the upper ground and the lower ground. When the antenna is installed on the upper part of the lower housing by providing a conductor member close to the antenna element when the other is grounded to the upper ground or the lower ground and the other part is at least slide open. It is possible to achieve a wider bandwidth and improved radiation efficiency.

  In addition, the call (wireless communication) is suitable for application to a terminal that can be performed in both the slide closed state and the slide open state, and the call quality in both states can be improved.

  Hereinafter, preferred embodiments of the present invention will be described in detail.

  The external configuration of the sliding portable wireless terminal according to the present embodiment is as shown in FIG. 1, and is composed of an upper housing 10 and a lower housing 20 that can be opened and closed in a sliding manner.

  FIG. 4A shows a schematic configuration of a sliding portable wireless terminal employing the short stub structure of the present invention. 4A (a) shows the internal structure when the terminal is viewed from the side when the slide is closed, and FIG. 4A (b) shows the terminal when viewed from the side. In this figure, parts not directly related to the present invention such as a relay flexible cable are not shown. As is apparent from the figure, a short, which is a linear conductor in this example, is placed in a space between the upper ground (ground plane) 16 in the upper casing and the lower ground (ground plane) 26 in the lower casing. The stub (conductor member) 31 is installed so that the tip (free end) portion thereof is close to the antenna element 24. The other end of the short stub 31 is grounded to the lower ground 26 via the adjustment element 32. The adjustment element 32 is a reactance element including an inductor and a capacitor provided between the short stub 31 and the ground as necessary in order to ensure a sufficient electrical length with respect to the terminal structure and the used frequency.

  FIG. 4B shows an enlarged view around the antenna element. In this example, the lower ground 26 has a substantially rectangular planar shape, and a power feeding portion 25 is provided at the upper end corner of the lower ground 26. The free end is formed by being bent by approximately the width of the lower ground 26. On the other hand, the short stub 31 has a lower end connected to the lower ground 26 via an adjustment element 32 at the side of the lower ground 26, and a free end substantially parallel to the side of the lower ground 26. It extends to the vicinity of 24.

  FIG. 4C shows a configuration diagram of the antenna circuit. Although not shown in the above figure, the antenna element 24 can be connected to the power feeding unit 25 via the matching circuit 28. The short stub 31 is located between the upper ground 16 and the lower ground 26, and coupling is performed between them.

  FIG. 5A shows a specific size of the antenna structure shown in FIG. 4B, and FIGS. 5B, 5C, and 5D show examples of actual measurement results of the antenna characteristics of the sliding portable wireless terminal employing such an antenna structure. . The short stub length, substrate (ground) size, antenna area size, and the like are as shown in FIG. 5A, and are the same size as the conventional example of FIG. 3A except for the short stub. This antenna is a built-in antenna in which a λ / 4 monopole antenna is tilted sideways, and the system used is assumed to be an 800-900 MHz band system in Japan, CDMA (95B & CDMA20001X), as in FIG. An inductor element is used as the adjustment element 32 at the short stub end, and antenna matching adjustment is performed by adjusting the constant of the inductor element. The antenna element length and the antenna matching circuit (not shown) are the same as those in FIG. did.

  FIG. 5B is graphs 41a and 42a showing the free space radiation efficiency when the slide is closed and when the slide is opened as the antenna characteristics of the slide portable wireless terminal employing the antenna structure of FIG. 5A. As can be seen by comparing this figure with FIG. 3B, it can be seen that the free space antenna radiation efficiency at the time of sliding open is greatly improved as compared with the antenna structure of FIG. 3A to which the present invention is not applied. FIG. 9B shows the radiation pattern measurement result of the antenna when the slide is opened when the present invention is applied. As is clear from FIG. 9A in the case where the present invention is not applied, the radiation levels on the front surface and the back surface of the terminal are almost the same and have a well-balanced radiation directivity. Furthermore, as can be seen in comparison with FIGS. 3C and D, the impedance characteristics of the antenna of this configuration shown in FIGS. 5C and D are also wide in both the open and closed states due to the short stub structure. I can see.

  Next, in the case of FIG. 5A to which the present invention is applied and in the case of FIG. 3A to which the present invention is not applied, antenna radiation characteristics and PAG (Pattern Average Gain) at the time of a terminal call as shown in FIG. The antenna horizontal plane radiation pattern average gain when using the terminal was measured and compared. The result is shown in FIG. This is a measurement result when XPR (Cross Polarization Ratio) is 0 dB. In addition, since there was no difference in the presence or absence of a short stub at the time of a slide closing, the result was described only about the case where this invention was applied.

  As is apparent from FIG. 6B, the PAG characteristic at the time of sliding opening is 2 dB or more when the present invention is applied (with a short stub). It can also be seen that the PAG characteristic when the slide is opened when the present invention is applied is equal to or better than the PAG characteristic when the slide is closed. From this, it can be said that the antenna characteristic at the time of the telephone call of the terminal according to the present embodiment has a good characteristic that is compatible with both slide closing and opening.

  The principle of improving antenna characteristics when the sliding portable wireless terminal to which the short stub structure of the present invention is applied is slid open was confirmed by electromagnetic field simulation. 7A and 7B are schematic views of the simulation model. A case where the former is not applied and a case where the latter is applied are shown. In both figures, only the periphery of the upper ground 16, the lower ground 26, the antenna element 24, and the short stub 31 relevant to the invention is shown in an enlarged view. The antenna element length, substrate (ground) size, short stub size, and the like used in the simulation conformed to those shown in FIGS. 3A and 5A. The electromagnetic field simulation uses the FDTD method (Finite Difference Time Domain Method), and the conductivity of the conductor portion is uniformly 10 ^ 5 [S / m] ("^" is an operator indicating a power) Is).

  FIG. 8 schematically shows the simulation result of the current distribution of the antenna structure of the present embodiment. 8A and 8B, a current distribution of 887 MHz was derived. Directions 43, 44, and 45 indicated by arrows in the figure indicate the general directions of currents flowing on the upper ground 16, the lower ground 26, and the short stub 31, respectively. The antenna characteristics of a portable wireless terminal greatly depend on the ground of the terminal. This is because the ground of the portable wireless terminal is small relative to the frequency band used, and therefore the ground is also operating as an antenna. From this simulation result, it was confirmed that a lot of high-frequency current was applied to the ground, and the ground was operating as an antenna element. Further, in the case of FIG. 8B in which the short stub structure of the present invention is applied, it has been found that a large high-frequency current is also carried on the short stub. The direction 45 of the current is opposite to the directions 43 and 44 of the current flowing through the upper ground. When the present invention is not applied, the upper ground 16 acts as a waveguide element, and the radiation pattern having a level difference between the front surface and the back surface of the terminal as shown in FIG. 9A described above applies the present invention. Thus, the waveguide element action of the upper ground 16 can be canceled by the current flowing in the direction opposite to the upper ground 16 of the short stub 31. As a result, radiation patterns of almost the same level were obtained on the front and back surfaces of the terminal as shown in FIG. 9B, and as a result, radiation efficiency was improved.

  FIG. 10 shows a comparison result of radiation efficiency in this simulation. Since the simulation model does not have terminal cabinets or relay flexible cables, and the electrical characteristics (conductivity) of conductive materials are uniform, the absolute value of efficiency is measured. Although there is a difference from the value, the fact that there is a large difference in the antenna efficiency before and after applying the present invention, that is, the presence or absence of a short stub, is similar in tendency to the actual measurement values shown in FIGS. 3A and 5A. I understand that.

  Next, antenna radiation characteristics when the slide is closed will be described. As described above, the short stub structure of the present invention has a great effect on improving the antenna radiation efficiency (41a in FIG. 5B) when the slide is opened. However, when the slide is closed, the short stub structure is different from the conventional antenna element. This brings about the effect of widening the antenna by proximity. However, the free space antenna radiation efficiency when the slide is closed in the antenna structures of FIGS. 3A and 5A is almost the same as the radiation efficiency 42 of FIG. 3B is compared with the radiation efficiency 42a of FIG. 5B. In this case, when the short stub structure of the present invention is applied and the constant of the adjustment element 32 at the end of the short stub 31 is selected with the highest priority given to the characteristics at the time of sliding open (that is, the action of the waveguide element on the upper ground is avoided). If this is the case, the electrical length of the short stub was too short when the slide was closed, and this is considered to be due to the fact that it was out of the original resonance.

  FIG. 11A is a graph showing how the antenna radiation efficiency changes when the slide is closed when the constant of the adjustment element (in this case, the inductor element Ls) in FIG. 5 is gradually increased to a large value. It shows with. In this way, by increasing the inductor element Ls, the resonance of the short stub is shifted to a lower frequency, and therefore, mainly the reception (downstream) band of the antenna radiation efficiency is improved (in FIG. 11A, (Encircled by circle 49). However, with the short stub termination constant L4 that is best when the slide is closed, the radiation efficiency in the transmission (upstream) band when the slide is opened is deteriorated as shown in FIG. 11B.

  As shown in FIG. 6, considering the antenna characteristics during a call, the short stub termination constant may be L1 regardless of whether the slide is opened or closed. There is a concern about deterioration on the reception band side, and it may be better to set the short stub termination constant to L4. Therefore, in order to eliminate such a concern, a circuit for switching the end of the short stub as shown in FIG. 12 may be inserted. In this example, a configuration is shown in which two inductor elements 32a and 32b (inductor values L1 and L4, respectively) having different constants are selectively switched and connected to the short stub 31 via a switch 51. In other words, the switching control unit 53 automatically switches the switch 51 so that the inductor element 32a is selected when the slide is opened or talked, and the inductor element 32b is selected when the slide is not closed or talked. The switching timing may be by sliding opening or closing, or may be the state of communication of the terminal and other states. In the former case, a slide opening / closing detection means is provided as the switching control unit 53, and in conjunction with the opening / closing detection, the electrical signal can be used for On / Off control of the switch 51 of the switching circuit at the short stub end of FIG. . In the latter case, an electrical signal can be used for On / Off control of the switch 51 in conjunction with a case where a call start key is pressed by a terminal control unit (not shown) as the switching control unit 53.

  The above description is based on the case where the ground length of the slide terminal is 90 mm and the short stub length is 50 mm in the 800-900 MHz band system in Japan. Since the short stub structure of the present invention avoids the influence of the upper ground, it can be easily imagined that the length of the upper ground is also a parameter. Further, depending on the length of the short stub, it can be assumed that the electrical length is sufficiently secured and no adjustment element is required. Therefore, in the structure of the present invention described above, depending on the length of the upper ground and the length of the short stub, the adjustment element at the end of the short stub may not be necessary or may be a capacitor element.

  Next, FIG. 13A shows another embodiment of the present invention. In this example, as a short stub 31a of another form of the short stub 31, an elongated conductor is formed in a U shape, and both ends thereof are short-circuited to a lower ground, or grounded via terminal adjusting elements 32a and 32b. Is the case. Even with such a structure, the effect of the action of the upper ground as a waveguide element can be avoided, so that it can be confirmed that the antenna radiation efficiency at the time of sliding open is improved as shown in FIG. 13B.

  FIGS. 15A and 15B show a short stub 31 b having a folded portion 38 in the vicinity of the fixed end 39 as a specific form of the short stub 31. Thereby, the electrical length of the short stub 31 can be adjusted without changing the length size on the installation of the short stub.

  In the antenna structure described above, the short stub is configured to be connected to the lower ground 26, but may be configured to be connected to the upper ground 16. FIGS. 16A and 16B show the internal structure of the terminal in FIG. 4A when the short stub 31 is connected to the upper ground 16 when the slide is closed and when the slide is opened.

  FIG. 17 shows the simulation results (a) and (b) of the current distribution of the antenna structure described in FIG. 8 with the simulation result (c) of the antenna structure of FIG. In the structure of FIG. 16 in which the short stub 31 is connected to the upper ground 16, it has been found that a large high-frequency current in the same direction 46 as the direction 45 is carried on the short stub 31. Therefore, it is expected that the antenna characteristics at the time of sliding opening similar to the above can be obtained. To change the characteristics when the slide is closed and when the slide is opened, a short stub end switching circuit as described with reference to FIG. 12 can be used.

  FIG. 18 is a diagram showing modified examples in which the shape (size) of the short stub and the ground contact position are different. FIG. 18 (a) shows no comparison with a short stub, and FIG. 18 (b) shows a comparison using the same short stub 31 as in FIG. 5A. In FIG. 18C, a planar (plate-like) short stub 31c having substantially the same width as the lower ground 26 is used, and grounding positions 32c and 32d are provided at both lower corners. FIG. 18D shows a short stub 31d having a half width of the short stub 31c shown in FIG. 18C, and a single ground contact position 32d is provided at the lower end corner. An adjustment element may be inserted in each grounding position.

  FIG. 19 is a graph showing the radiation characteristics of the antenna structures of FIGS. 18 (a) to 18 (d). From this figure, each antenna structure using the short stubs 31c and 31d shown in FIGS. 18C and 18D shows better radiation characteristics than those using the short stub 31 shown in FIG. 18B. I understand.

  FIG. 20 is a diagram showing modified examples of various short stubs in the case of short stub upper ground contact. FIG. 20A shows the case without a short stub as a comparison object for reference. The short stubs 31e and 31f in FIGS. 20 (c) and 20 (d) have the same shape and grounding position as the short stubs 31c and 31d in FIGS. 18 (c) and 18 (d) except that the grounding object is changed to the upper ground 16. Is the same. The short stub 31d in FIG. 20B has the same shape (and size) as the short stub 31f in FIG. 20D, but its installation position is on the side end on the side away from the power feeding portion 25, and is connected to the upper ground 16. The ground contact position 32c is also a side end opposite to 32d.

  FIG. 21 is a graph showing the radiation characteristics of the antenna structures shown in FIGS. From this figure, each antenna structure using the short stubs 31d, 31e, 31f of FIGS. 20B to 20D shows better radiation characteristics than the case without the short stub of FIG. I understand that.

  The preferred embodiments of the present invention have been described above, but various modifications and changes other than those mentioned above can be made.

It is the figure which showed the outline of the general slide-type portable radio | wireless terminal. It is the figure which showed an example of the outline of the internal structure of the slide type portable radio | wireless terminal shown in FIG. It is a figure which shows the antenna structure of the slide type portable radio | wireless terminal in which the antenna element was installed in the lower housing | casing upper part. It is the figure which showed the radiation efficiency of the antenna structure of FIG. 3A. It is the figure which showed the impedance characteristic at the time of slide opening of the antenna structure of FIG. 3A. It is the figure which showed the impedance characteristic at the time of slide closing of the antenna structure of FIG. 3A. It is the schematic which looked at the internal structure of embodiment of this invention from the side. FIG. 3 is an enlarged schematic view around an antenna element in a lower housing according to an embodiment of the present invention. It is a circuit block diagram of the antenna of embodiment of this invention. It is the figure which specified the specific size of the antenna structure of FIG. 4B. It is a figure which shows an example of the measurement result of the antenna radiation efficiency of the slide type portable radio | wireless terminal which employ | adopted the antenna structure of FIG. 5A. It is the figure which showed the impedance characteristic at the time of slide opening of the antenna structure of FIG. 5A. It is the figure which showed the impedance characteristic at the time of slide closing of the antenna structure of FIG. 5A. It is the figure which showed an example of the comparison of the antenna characteristic in the state in which the user is talking of the sliding portable wireless terminal to which this invention is applied, and the sliding portable wireless terminal which is not applied. It is the schematic of the simulation model of the slide-type portable radio | wireless terminal to which this invention is not applied. It is the schematic of the simulation model of embodiment of this invention. It is the figure which showed the outline of the high frequency current distribution on a terminal ground at the time of a slide opening among the simulation results by the simulation model shown to FIG. 7A and 7B. It is the figure which showed an example of the measurement result of the antenna radiation pattern at the time of a slide opening of the slide type portable radio | wireless terminal to which this invention is not applied. It is the figure which showed an example of the measurement result of the antenna radiation pattern at the time of slide opening of embodiment of this invention. It is the figure which showed the antenna radiation efficiency at the time of a slide opening among the simulation results by the simulation model shown to FIG. 7A and 7B. In embodiment of this invention, it is the figure which showed the example of the change of the antenna characteristic at the time of a slide closing at the time of changing the constant of the element for adjustment installed in the short stub termination | terminus. It is the figure which showed the example of the change of the antenna characteristic at the time of the slide opening corresponding to FIG. 11A. It is the figure which showed the circuit diagram which inserted the switching circuit for switching the element for adjustment in embodiment of this invention. It is a figure which shows the modification of the antenna element which concerns on other embodiment of this invention. It is the figure which showed an example of the measurement result of radiation efficiency about the antenna structure of FIG. 13A. It is a figure which shows the direction of each axis | shaft of a portable radio | wireless terminal, and the terminal at the time of the measurement of FIG. 9A. It is a figure which shows an example of the specific form of the short stub in embodiment of this invention. It is a figure which shows the internal structure of the terminal at the time of connecting the short stub in embodiment of this invention to an upper side ground. It is the figure which added and added the simulation result (c) of the antenna structure of FIG. 16 to the simulation results (a) and (b) of the current distribution of the antenna structure described in FIG. It is the figure which showed the modification from which the shape (size) of a short stub and the earthing | grounding position differ in embodiment of this invention. It is a figure showing the radiation characteristic of each antenna structure of Fig.18 (a)-(d). It is the figure which showed the modification of various short stubs in the case of short stub upper side grounding in embodiment of this invention. It is a figure showing the radiation characteristic of each antenna structure of Fig.20 (a)-(d).

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Upper housing | casing, 11 ... Receiver part, 12 ... Liquid crystal display part, 15 ... Upper operation part, 16 ... Upper ground, 17 ... Connection part, 19 ... Relay flexible cable, 20 ... Lower housing, 21 ... Lower side Operation part, 23 ... Microphone part, 24 ... Antenna element, 25 ... Feeding part, 26 ... Lower ground, 27 ... Connection part, 28 ... Matching circuit, 31 ... Short stub, 31a ... Short stub, 31b ... Short stub, 31c ... Short stub, 31d ... Short stub, 31e ... Short stub, 31f ... Short stub, 32 ... Adjusting element, 32a ... Inductor element, 32b ... Inductor element, 32c ... Grounding position, 32d ... Grounding position, 38 ... Folded part, 39 ... Fixed end, 41 ... Radiation efficiency, 42 ... Radiation efficiency, 41a ... Graph, 42a ... Graph, 43 ... Direction, 44 ... Direction, 4 ... Direction, 46 ... direction, 51 ... switch, 53 ... switching control unit

Claims (8)

In the portable wireless terminal device that opens and closes by sliding the upper housing relative to the lower housing,
An antenna element installed at the top of the lower housing;
An upper ground installed in the upper housing;
A lower ground installed in the lower housing;
A conductor member installed in a space between the upper ground and the lower ground, wherein at least a part is grounded to the upper ground or the lower ground, and the other part is at least close to the antenna element when sliding open; ,
An adjustment element for grounding the conductor member to the upper ground or the lower ground,
A portable wireless terminal device using a switching circuit that switches between a plurality of elements as the adjustment element . The portable wireless terminal device according to claim 1 , further comprising: a switching control unit that detects a slide open / close state, wherein the switching circuit is switched according to the slide open / close state. The portable wireless terminal device according to claim 1, further comprising a switching unit that detects presence / absence of a call, and switching the switching circuit according to the presence / absence of the call.   The portable wireless terminal device according to claim 1, wherein the conductor member is linear and is grounded at one point.   The portable wireless terminal device according to claim 1, wherein the conductor member is linear and is grounded at a plurality of points.   The portable wireless terminal device according to claim 1, wherein the conductor member has a planar shape and is grounded at one point.   The portable wireless terminal device according to claim 1, wherein the conductor member has a planar shape and is grounded at a plurality of points. In the portable wireless terminal device that opens and closes by sliding the upper housing relative to the lower housing,
An antenna element installed on top of the lower housing;
An upper ground installed in the upper housing;
A lower ground installed in the lower casing;
A conductor member disposed so that at least a part thereof is grounded to the upper ground or the lower ground and the other part is at least close to the antenna element at the time of sliding open;
A plurality of adjusting elements for grounding the conductor member to the upper ground or the lower ground;
And a switching means for switching to selectively use the plurality of adjustment elements.