JP5286307B2 - Antenna and portable wireless terminal - Google Patents

Description

  The present invention relates to an antenna including three antenna elements and a portable wireless terminal including the antenna.

  In recent years, portable wireless terminals typified by mobile phones and PDA terminals have been reduced in size and thickness, and antennas have been built in to improve the design of portable wireless terminals. Furthermore, functions required for portable wireless terminals are not limited to cellular communication such as voice communication and e-mail, but diversified functions installed in portable wireless terminals such as international roaming function, one-segment viewing, GPS, wireless LAN communication, and Bluetooth communication. Therefore, an antenna corresponding to each function is required. For this reason, it is necessary to arrange a plurality of antenna elements in a limited space of the portable wireless terminal.

  If each antenna element is arranged in a separate position in the casing of the portable wireless terminal, it is possible to suppress the mutual interference between the respective antenna elements while ensuring the antenna characteristics. In addition to the realization, it is indispensable to arrange a plurality of antenna elements in the same space when considering the multi-function of the mobile radio terminal.

  As a technique for arranging a plurality of antenna elements in the same space, a technique for mounting an antenna on a foldable portable wireless terminal shown in FIG. 15 or a technique described in Patent Document 1 and Patent Document 2 is disclosed. Yes.

  With reference to FIG. 15, the antenna element arrangement of the folding portable wireless terminal in the prior art will be described. Here, the prior art shown in FIG. 15 has an antenna configuration in which a cellular antenna and a GPS antenna are arranged on a connecting member that connects an upper housing and a lower housing in a foldable wireless communication terminal. 15 is a perspective view showing a configuration of a conventional portable wireless terminal 900, FIG. 15A is a transparent top view of the portable wireless terminal 900, and FIG. 15B is a transparent side view of the portable wireless terminal 900. FIG. 15C is a diagram showing a state in which the antenna base 915 is removed from FIG.

  The portable wireless terminal 900 includes a first antenna element 911 that operates in a 800 to 900 MHz band, a third antenna element 913 that operates in a 1.7 to 2.1 GHz band, and a wireless for cellular communication for cellular communication. And a second antenna element 912 that operates in the 1.5 GHz band and a GPS radio unit circuit 923 for use of GPS.

  As shown in FIG. 15A, the first antenna element 911 and the third antenna element 913 are formed on an antenna base 915 disposed on the circuit board 920, and are located on the outermost side of the housing 901. Has been placed. This is to secure the distance from the first antenna element 911 and the third antenna element 913 to the conductive member or shield member on the circuit board 920 in the housing 901 as much as possible, which is advantageous in terms of antenna characteristics. Become.

  On the other hand, as shown in FIG. 15C, the second antenna element 912 is formed on the circuit board 920 with a board pattern. Therefore, the antenna characteristics of the second antenna element 912 are as much as the distance from the conductive member or shield member on the circuit board 920 in the housing 901 cannot be ensured compared to the case where the antenna is formed on the antenna base 915. Deteriorate. However, since the second antenna element 912 is formed by the substrate pattern on the circuit board 920, the first antenna element 911 and the third antenna element 911 are more than the case where the second antenna element 912 is formed on the antenna base 915. Since it is possible to take a physical distance from the antenna element 913, it is possible to suppress deterioration of antenna characteristics due to mutual interference between the antenna elements 911 to 913. In general, since cellular communication has a higher priority than using GPS communication, the conventional technology provides a wireless communication terminal according to the priority by arranging each antenna element as described above. can do.

  Thus, the arrangement of each antenna element in the same space is very important in considering the characteristics of the antenna. In particular, in a complex antenna comprising three antenna elements, it is very useful to provide a more favorable arrangement of each antenna element.

Next, the technique described in Patent Document 1 will be described. In the technique described in Patent Document 1, a technique is disclosed in which three antenna elements are arranged in the same space and two antenna elements of the three antenna elements are electromagnetically coupled to each other to correspond to three frequency bands. ing.
Further, in the technique described in Patent Document 2, by arranging the antenna element having a loop electrode and the antenna element having a monopole electrode in the same space, it is possible to provide an antenna with small mutual interference between the antennas. Is disclosed.

JP 2007-266669 A (released on October 11, 2007) JP 2008-252507 A (released on October 16, 2008)

  However, for example, when three antenna elements are used for the same system as in WCDMA communication using Band XI, the configuration shown in FIG. 15 is not preferable. Because, when three antenna elements are used for the same system, (A) the characteristics of all the antenna elements are good, and (B) the end portions for connection to the radio circuit of each antenna element are not separated. Because it is required.

  That is, as in the prior art shown in FIG. 15, if a configuration is used in which some antenna elements are used for a certain system and other antenna elements are used for another system, the priority is relatively high. It is also possible to sacrifice the antenna characteristics of the antenna elements used for low systems. However, when three antenna elements are used for the same system, the antenna characteristics of all the antenna elements are required to be good.

  Also, even if the connection ends of antenna elements used for different systems are separated from each other, there is no particular problem because the radio circuit connected to each other is different, but connection of antenna elements used for the same system When the end portions for use are separated from each other, the connection end portion of one of the antenna elements and the radio circuit connected to the antenna element are also separated, which is not preferable.

  Further, in the technique described in Patent Document 1, it is considered that two of the three antenna elements are electromagnetically coupled to generate resonance, but it is represented by a non-excitation element. However, the resonance generated in this way has a problem that the band is narrow, and it is difficult to improve the characteristics of all the antenna elements.

  In the embodiment described in Patent Document 2, since the tip of the loop electrode is arranged at the end near the ground of the antenna arrangement region, the loop electrode is used similarly to the antenna characteristic of the second antenna element in FIG. The antenna characteristics of the corresponding frequency band are sacrificed. In another embodiment described in Patent Document 2, since the tip end portion of the monopole electrode is arranged at the end portion near the ground in the antenna arrangement region, similarly to the antenna characteristic of the second antenna element in FIG. Monopole electrodes sacrifice the antenna characteristics of the corresponding frequency band. Thus, even in Patent Document 2, it is difficult to improve the characteristics of all the antenna elements.

  Thus, when three antenna elements are used for the same system, unlike the case where each antenna element is used for a plurality of systems as in the prior art, (A) antenna characteristics of all antenna elements. Both (B) and (B) the connection part to the radio | wireless part circuit of each antenna element are not separated are calculated | required.

  Accordingly, the inventors of the present application have made extensive studies on the arrangement of each antenna element suitable for the case where three antenna elements are used for the same system. As a result, the second antenna element 112 is replaced with the first antenna element 111. It has been found that the antenna element is suitably disposed between the antenna element 113 and the third antenna element 113.

  FIG. 16 is a top view showing the arrangement of the novel antenna element. As shown in FIG. 16, by arranging the second antenna element 112 between the first antenna element 111 and the third antenna element 113, the first antenna element 111, The second antenna element 112 and the third antenna element 113 can be successfully arranged. Therefore, unlike the arrangement of the antenna elements according to the prior art as shown in FIG. 15, the second antenna element 912 is formed on the circuit board 920 to avoid deterioration of characteristics, and more preferably, the first The antenna characteristics of the second and third antenna elements 111 to 113 can be improved.

  Further, the second antenna element 112 is disposed between the first antenna element 111 and the third antenna element 113, and any of the first, second and third connection end portions 111b to 113b is provided. The first, second, and third connection end portions 111b to 113b are not separated from each other successfully by being disposed at a position closer to the third tip end portion 113a than the first tip end portion 111a. Can be arranged as follows.

  As described above, according to the arrangement of the antenna elements shown in FIG. 16, (A) the characteristics of all the antenna elements are good, and (B) the antennas where the connection parts of the respective antenna elements to the radio circuit are not separated from each other. Can be realized.

  However, in the arrangement of the antenna elements shown in FIG. 16, the second antenna element 112 is arranged so as to be sandwiched between the first antenna element 111 and the third antenna element 113. For this reason, a new problem arises that the antenna characteristics of the second antenna element 112 deteriorate due to the influence of shadowing by being surrounded by the first antenna element 111 and the third antenna element 113. I understood. In particular, when considering miniaturization of the antenna, the arrangement interval of the first, second, and third antenna elements 111 to 113 is further narrowed, so that the antenna characteristics of the second antenna element 112 are significantly deteriorated. Become.

  In the arrangement of the conventional antenna element shown in FIG. 15, the first antenna element 911 and the third antenna element 913 are arranged on the antenna base 915, and the second antenna element 912 is arranged on the circuit board 920, respectively. . For this reason, since the second antenna element 912 is physically separated from the first antenna element 911 and the third antenna element 913, the antenna characteristic deterioration due to mutual interference between the antenna elements is small, and the second antenna element 912 There is no new problem that the antenna characteristics of the antenna element 912 deteriorate.

  The present invention has been made in view of the above-described new problems, and its purpose is to use each antenna element for the same system in an antenna having three antenna elements. The main object of the present invention is to provide an antenna capable of obtaining good characteristics.

  In order to solve the above problems, an antenna of the present invention includes a first antenna element that operates in a first frequency band, and a second antenna that operates in a second frequency band higher than the first frequency band. An antenna comprising an element and a third antenna element that operates in a third frequency band higher than the second frequency band, wherein each of the first, second, and third antenna elements is a radio unit First, second, and third connection end portions that are ends connected to the circuit, and first, second, and third end portions that are opposite to the first, second, and third connection end portions 2 and 3 and a 2nd antenna element is arrange | positioned between the 1st antenna element and the 3rd antenna element, and the 1st, 2nd and 3rd connection is provided. Any of the end portions for use is more third than the first tip portion. It is arranged at a position close to the end portion, and includes a first wiring and a second wiring for connecting to the radio unit circuit, and the first wiring is provided with first and third connection end portions. The second wiring is connected to the second connection end, and the first wiring includes a frequency control means for blocking an electric signal in the second frequency band. It is said.

  The antenna further includes first, second, and third tip regions including first, second, and third tip portions, and each of the first, second, and third tip regions is provided. The antenna is preferably disposed at an end in a certain direction.

  In the antenna of the present invention, it is preferable that the shadow of the second antenna element is inserted into the shadow of the first antenna element and the shadow of the third antenna element when projected onto a certain plane. .

  In the antenna of the present invention, it is preferable that the first connection end and the third connection end are one.

  According to the above configuration, the antenna according to the present invention includes the longest first antenna element, the second antenna element, and the shortest third antenna among the three antenna elements. It has an element.

  In order to arrange the first, second and third connection end portions so as not to be separated from each other, the first antenna element is the longest of the first, second and third antenna elements, and the third Since the antenna element is the shortest, the distance from the area where the first, second and third connection end portions are arranged to the first, second and third tip portions is from the area to the first tip. The distance to the part must be the longest, and the distance to the third tip must be the shortest.

  Here, according to said structure, the 2nd antenna element is arrange | positioned between the 1st antenna element and the 3rd antenna element. Therefore, the first tip portion, the second tip portion, and the third tip portion are arranged in this order. The first, second, and third connection end portions are disposed at positions closer to the third tip portion than the first tip portion. Therefore, the distance from the area where the first, second, and third connection end portions are arranged to the first, second, and third tip portions satisfies the above condition. Therefore, according to said structure, the antenna from which the connection part to the radio | wireless part circuit of the 1st, 2nd and 3rd antenna element is not mutually separated is realizable.

  In addition, according to the above configuration, the first wiring and the second wiring for connecting to the radio unit circuit are provided, and the first wiring is connected to the first and third connection end portions. Further, the first wiring is provided with a frequency control means for blocking the electric signal in the second frequency band. For this reason, in the second frequency band, since the influence of shadowing of the first antenna element and the third antenna element surrounding the second antenna element is suppressed, interference with the second antenna element is suppressed. Is done. Thereby, since interference between antenna elements is suppressed, degradation of the antenna characteristics of the second antenna element can be prevented.

  Thus, according to the above configuration, it is possible to provide an antenna capable of obtaining good characteristics even when each antenna element is used for the same system.

  Furthermore, according to said structure, the electric power feeding system from a radio | wireless part circuit to a 1st antenna element and an electric power feeding system from a radio | wireless part circuit to a 3rd antenna element are integrated. When there are many power supply systems, an antenna matching circuit and contact springs between the circuit board and the antenna element are required for each, and the occupied area of the antenna component increases. Therefore, on the circuit board on which other conductive members are mounted. Although the mountable area of the conductive member is reduced, according to the above configuration, it is possible to suppress a decrease in the mountable area on the circuit board on which the conductive member other than the antenna component is mounted.

  It should be noted that the antenna according to the present invention can be suitably applied even when all the antenna elements are used for using a plurality of systems.

  Further, by arranging the first, second, and third tip regions outside the wireless device in which the antenna element is built, the first, second, and third tip regions are in a certain direction in the entire antenna. Therefore, the first, second, and third tip portions can be disposed outside the wireless device by setting the direction to the direction toward the outside of the wireless device. it can. Therefore, according to said structure, the antenna with the favorable characteristic of all the antenna elements can be implement | achieved easily.

  The antenna according to the present invention further includes a matching circuit for matching the first and third antenna elements on the first wiring, and the first and third connection end portions of the first wiring. It is preferable that the frequency control means is provided in a portion connecting the matching circuit.

  According to said structure, passage of the electric signal of a 2nd frequency band is blocked | prevented by a frequency control means between the 1st and 3rd connection edge part and a matching circuit. For this reason, since the interference with the 2nd antenna element 112 by the 1st antenna element and the 3rd antenna element is controlled, degradation of the antenna characteristic of the 2nd antenna element can be prevented.

  Further, in the antenna of the present invention, the first and third antenna elements are operated such that the first and third antenna elements operate as non-excited elements that are electromagnetically coupled to the second antenna element that operates in the second frequency band. It is preferable that the total electrical length of the three antenna elements is set.

  In the antenna of the present invention, the total electrical length of the first and third antenna elements is preferably approximately ½ of the wavelength corresponding to the second frequency band.

  According to the above configuration, since the first antenna element and the third antenna element can be used as a non-excitation element, the antenna characteristics of the second antenna element can be improved.

  In the antenna of the present invention, a matching circuit for matching the first and third antenna elements is provided on the first wiring, and the matching circuit of the first wiring and the radio unit circuit are provided. The connecting portion is provided with the frequency control means, and the portion including the first and third antenna elements and the matching circuit has an impedance in the second frequency band and an impedance in the first and third frequency bands. It is good also as a higher structure.

  According to the above configuration, the passage of the electric signal in the second frequency band can be suitably prevented by the frequency control means provided between the matching circuit and the radio unit circuit. For this reason, interference to the second antenna element by the first antenna element and the third antenna element is suppressed, and deterioration of the antenna characteristics of the second antenna element can be prevented.

  In the antenna of the present invention, the frequency control means includes any one selected from the group consisting of a band elimination filter, a low pass filter, a high pass filter, a band pass filter, a switch, a PIN diode, an FET, a MEMS, and a phase shifter. I like that.

  According to the above configuration, the electrical signal in the second frequency band is blocked by using any one of the band elimination filter, the low pass filter, the high pass filter, the band pass filter, the switch, the MEMS, the FET, the PIN diode, and the phase shifter. It is possible to easily realize the frequency control means.

  In the antenna of the present invention, it is preferable that the first, second and third antenna elements are formed on the same antenna base.

  According to the above configuration, since the first, second, and third antenna elements can be handled as one component, it contributes to the reduction in the number of components incorporated in the radio device and the efficiency in assembling the radio device. Can do.

  In order to solve the above-described problems, a portable wireless terminal according to the present invention includes the antenna and the wireless unit circuit, and the first, second, and third antenna elements are all connected to the wireless unit circuit. It is characterized by being.

  According to the above configuration, since the antenna according to the present invention is provided, and each antenna element of the antenna is connected to the same radio unit circuit, a portable radio terminal that takes advantage of the antenna according to the present invention is provided. be able to.

  As described above, the antenna of the present invention includes the first antenna element that operates in the first frequency band, the second antenna element that operates in the second frequency band higher than the first frequency band, A third antenna element that operates in a third frequency band higher than the second frequency band, wherein each of the first, second, and third antenna elements is connected to a radio circuit. First, second, and third connecting ends, and the first, second, and third ends that are opposite to the first, second, and third connecting ends. The second antenna element is disposed between the first antenna element and the third antenna element, and the first, second and third connection end parts are Both are closer to the third tip than the first tip. Is provided with a first wiring and a second wiring for connecting to the radio unit circuit, the first wiring is connected to the first and third connection ends, The second wiring is connected to the second connection end, and the first wiring includes frequency control means for blocking an electric signal in the second frequency band.

  Therefore, in the antenna having three antenna elements, there is an effect that it is possible to realize an antenna that can obtain good characteristics even when each antenna element is used for the same system.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows schematic structure of the portable radio | wireless terminal which concerns on 1st Embodiment of this invention, Fig.1 (a) is a see-through | perspective top view of a portable radio | wireless terminal, FIG.1 (b) is a see-through | perspective view of a portable radio | wireless terminal. It is a side view. It is a figure which shows schematic structure of the antenna with which the portable radio | wireless terminal which concerns on 1st Embodiment is provided. It is the schematic which shows the structure of the frequency control means which concerns on 1st Embodiment. It is an image figure for demonstrating the passage characteristic of the frequency control means 150 which concerns on 1st Embodiment, and has shown the conceptual structure in a 2nd frequency band. FIG. 5A is a graph showing the frequency characteristics of the antenna gain of the second antenna element according to the first embodiment, and FIG. 5A shows the amount of change in the antenna gain of the second antenna element depending on the presence or absence of the frequency control means. (B) shows the amount of change in the antenna gain of the second antenna element when the first antenna element and the third antenna element are used as non-excitation elements and when not used. It is a graph which shows an example of the passage characteristic of the frequency control means concerning this embodiment. It is a figure which shows schematic structure of the modification of the antenna which concerns on 1st Embodiment. It is a top view which shows schematic structure of the frequency control means shown in FIG. It is a figure which shows schematic structure of the other modification of the antenna of the portable radio | wireless terminal which concerns on 1st Embodiment. It is a figure which shows schematic structure of the antenna which concerns on 2nd Embodiment. It is a Smith chart which shows the frequency characteristic of the impedance of the frequency control means which concerns on 2nd Embodiment. It is a figure which shows schematic structure of the modification of the antenna which concerns on 2nd Embodiment. It is a figure which shows schematic structure of the other modification of the antenna which concerns on 2nd Embodiment. It is a graph which shows the average gain of the 2nd antenna element measured in the Example. It is a perspective view which shows the inside of the housing | casing in which the antenna of the portable wireless terminal which concerns on a prior art is arrange | positioned. It is a top view which shows arrangement | positioning of a novel antenna element. It is a figure which shows the variation of the antenna which concerns on one Embodiment of this invention. It is a figure which shows the variation of the antenna which concerns on one Embodiment of this invention. It is a figure which shows schematic structure of the radio | wireless part circuit which concerns on other embodiment of this invention.

[First Embodiment]
The embodiment (first embodiment) of the present invention will be described below with reference to FIGS. In the following description, the antenna according to the present invention is described as an antenna provided in a portable wireless terminal that performs wireless communication for a call with a base station. However, the antenna according to the present invention is not limited to an antenna provided in a portable wireless terminal that performs radio communication for a call with a base station, and is generally applicable to an antenna that receives and / or transmits a carrier wave on which some signal is superimposed. The wireless device other than the portable wireless terminal may be provided.

  FIG. 1 is a diagram illustrating a schematic configuration of a portable wireless terminal 100 according to an embodiment of the present invention, FIG. 1A is a perspective top view of the portable wireless terminal 100, and FIG. 2 is a perspective side view of the portable wireless terminal 100. FIG. As shown in FIG. 1, the portable wireless terminal 100 includes a first casing 101 and a second casing 102 that are connected by a connecting member 103. In addition, the first housing 101 contains a circuit board 120. An antenna base 115 is disposed at one end of the circuit board 120. On the antenna base 115, the 1st antenna element 111, the 2nd antenna element 112, and the 3rd antenna element 113 which comprise the antenna 110 which concerns on this embodiment are provided. The first, second, and third antenna elements 111 to 113 and the antenna base 115 may be collectively referred to as an antenna assembly. Further, in this specification, the “antenna” refers to a configuration including the connection from the antenna element to the wireless unit circuit 121. The circuit board 120 includes a wireless circuit 121 for the cellular communication system, a camera (metal member) 122, a first matching unit (matching circuit) 133, a second matching unit (matching circuit) 134, and a frequency control unit 150. Etc. are provided.

  Each of the first, second, and third antenna elements 111 to 113 extends in the vicinity of the connection surface of the antenna base 115, and the end portion on the side connected to the radio circuit 121 is connected to the connection surface. A first connection end portion 111b, a second connection end portion 112b, and a third connection end portion 113b. The first connecting end 111b and the third connecting end 113b are one, and the first antenna element 111 and the third antenna element 113 are integrated into one system as the connecting end 114. Has been. The connection end 114 and the second connection end 112b are connected to the wiring (first wiring 130...) On the circuit board 120 through connection terminals such as springs provided on the circuit board 120 facing each other. The connection end 114 is connected to the frequency control means 150, and the second connection end 112 b is connected to the second matching section 134.

  Here, the first wiring 130 and the second wiring 131 are composed of, for example, a microstrip line, a triplate line, a coaxial cable, and the like, and connect the antenna assembly and the radio circuit unit so that there is no mismatch. Refers to wiring. In FIG. 1, the connection end 114 is provided on the antenna base 115. However, as shown in FIG. 19, a branch point 114 'may be provided on the circuit board 120. In this case, the first connection end portion 111b and the third connection end portion 113b are connected to each other at a branch point 114 ′ via connection terminals such as springs provided on the circuit board 120 facing each other. After being integrated into one system, it is connected to the first wiring 130.

  The first, second and third antenna elements 111 to 113 are also provided on the top surface of the antenna base 115 on the side opposite to the first, second and third connection ends 111b to 113b. A first tip portion 111a, a second tip portion 112a, and a third tip portion 113a. The first, second and third tip portions 111a to 113a are not connected to other conductive members and are open ends. Further, a peripheral region (including the first tip portion 111a) of the first tip portion 111a in the first antenna element 111 is referred to as a first tip region 111c. Similarly, the second tip region 112c and the third tip portion of the third antenna element 113 are the peripheral region (including the second tip portion 112a) of the second tip portion 112a of the second antenna element 112. A peripheral region of 113a (including the third tip portion 113a) is referred to as a third tip region 113c.

  The first frequency band in which the first antenna element 111 operates, the second frequency band in which the second antenna element 112 operates, and the third frequency band in which the third antenna element 113 operates follow this order. The frequency is high. In the present embodiment, as an example, the first frequency is 800 to 900 MHz band for WCDMA, AMPS, EGSM, CDMA2000 (BandClass 0, BandClass 3 etc.), and the second frequency band is WCDMA Band XI, GPS. The case of using the 1.7 to 2.1 GHz band such as WCDMA, DCS, PCS, CDMA (Band Class 6, etc.) as the third frequency band for the 1.5 GHz band for etc. will be described. The present invention is not limited to this, and the present invention can be applied as long as the second frequency band is higher than the first frequency band and the third frequency band is higher than the second frequency band.

  In general, the length of the antenna element is inversely proportional to the operating frequency. That is, the antenna element of a low frequency band becomes longer. Accordingly, the first antenna element 111, the second antenna element 112, and the third antenna element 113 are shortened in this order.

  The radio unit circuit 121 performs cellular communication using three frequency bands, and is connected to each of the first matching unit 133 and the second matching unit 134. In this specification, “radio section circuit” means a transmission circuit, a reception circuit, an antenna switching switch, a demultiplexing that separates the flow from the transmission circuit to the antenna and the flow from the antenna to the reception circuit. It is a general term for circuits composed of at least one of components such as filters and ICs.

  The first matching unit 133 and the second matching unit 134 match the output impedance and the input impedance. The first matching unit 133 matches the first antenna element 111 and the third antenna element 113, and the second matching unit 134 matches the second antenna element 112. As the first matching unit 133, it is preferable to use a parallel resonant circuit loaded in parallel to the first antenna element 111 and the third antenna element 113 and connected to the ground. In addition, the 1st matching part 133 and the 2nd matching part 134 can be abbreviate | omitted suitably according to the objective.

  The frequency control means 150 is disposed between the connection end portion 114 and the first matching portion 133 via the first wiring 130, and prevents passage of an electric signal in the second frequency band. As the frequency control means 150, for example, a device including a band elimination filter (for example, a notch filter), a switch, a MEMS (Micro Electro Mechanical Systems), a FET (Field Effect Transistor), a PIN diode, and a phase shifter is used. Can do. When an active element such as a switch or a PIN diode is used as the frequency control means 150, a power supply circuit or wiring for operating the active element may be additionally provided. Details of the frequency control means 150 will be described later.

  As described above, in the antenna 110 according to this embodiment, the first, second, and third tip regions 111c to 113c of the first, second, and third antenna elements 111 to 113 are all included in the mobile radio terminal 100. The second antenna element 112 is disposed between the first antenna element 111 and the third antenna element 113, and is disposed at an end portion closer to the outer edge of the first casing 101. The first, second, and third connection end portions 111b to 113b are all disposed at positions closer to the third tip end portion 113a than the first tip end portion 111a.

  That is, the first, second, and third tip regions 111c to 113c are arranged at the end portion closer to the outer edge of the first casing 101 of the portable wireless terminal 100, so that the first, second, and The antenna characteristics of the third antenna elements 111 to 113 are good. In other words, it is less necessary to increase the antenna dimensions of the first, second, and third antenna elements 111 to 113 in order to ensure the antenna characteristics of the first, second, and third antenna elements 111 to 113. Thus, it is possible to meet the recent demands for downsizing and thinning portable radio terminals.

  From another viewpoint, the first, second, and third tip regions 111c to 113c are viewed from the side opposite to the side where the conductive member such as the wireless circuit 121 and the camera 122 is present. Since it is not covered with other antenna elements, the antenna characteristics of any of the antenna elements 111 to 113 are good.

  Further, the second antenna element 112 is disposed between the first antenna element 111 and the third antenna element 113, and any of the first, second and third connection end portions 111b to 113b is provided. The first, second, and third connection end portions 111b to 113b are not separated from each other successfully by being disposed at a position closer to the third tip end portion 113a than the first tip end portion 111a. Can be arranged as follows.

  Note that in this specification, “the second antenna element 112 is disposed between the first antenna element 111 and the third antenna element 113” means that the first antenna element 111 and the third antenna element This means that most of the second antenna element 112, at least half of the second antenna element 112, is disposed in the space between the antenna element 113. For example, as shown in FIG. 1 (a), when projected onto a plane parallel to the substrate surface of the circuit board 120, the shadow of the second antenna element 112 is the same as the shadow of the first antenna element 111 and the third antenna element 113. Including the state of being inserted into the shadow. The entire shadow of the second antenna element 112 does not have to be inserted into the shadow of the first antenna element and the shadow of the third antenna element 113. 50% should be inserted. That is, for the most part, the second antenna element 112 only needs to be inserted between the first antenna element 111 and the third antenna element 113. From another point of view, “the second antenna element 112 is disposed between the first antenna element 111 and the third antenna element 113” means that the first antenna element 111, the first antenna element 111, The second antenna element 112 and the third antenna element 113 are arranged in this order along a certain direction, and are preferably arranged in the order from the side closer to the conductive member. Including that.

  The reason why the first, second and third antenna elements 111 to 113 are preferably arranged in this manner will be described below with reference to FIG. FIG. 17A is a schematic diagram illustrating a schematic configuration of an antenna 110 according to an embodiment.

  First, as described above, the lengths of the first, second and third antenna elements are the longest in the first antenna element 111 and the second antenna element 112 is shorter than the first antenna element 111. The third antenna element 113 is the shortest. Therefore, in order to arrange the first, second, and third connection end portions 111b to 113b close to each other, from the area where the first, second, and third connection end portions 111b to 113b are arranged. The first, second, and third tip portions 111a to 113a each have the longest distance from the area to the first tip portion 111a, and the distance from the area to the third tip portion 113a. Need to be the shortest. Here, when the first, second, and third antenna elements 111 to 113 are not arranged as described above, it is difficult to satisfy such a condition.

  That is, in the present embodiment, the second antenna element 112 is arranged between the first antenna element 111 and the third antenna element 113, or the first antenna element 111 and the second antenna element. 112 and the third antenna element 113 are arranged in this order along a certain direction (direction D1 in FIG. 17A). Therefore, the first, second, and third tip portions 111a to 113a are arranged in the order of the first tip portion 111a, the second tip portion 112a, and the third tip portion 113a. In the present embodiment, the first, second, and third connection end portions 111b to 113b are all disposed at positions closer to the third tip portion 113a than the first tip portion 111a. Therefore, the respective distances from the area where the first, second and third connection end portions 111b to 113b are arranged to the first, second and third tip end portions 111a to 113a are changed from the area to the first. The distance from the first tip 111a is the longest, and the distance from the area to the third tip 113a can be the shortest.

  Thus, by arranging the first, second, and third antenna elements 111-113 as described above, the first, second, and third connection end portions 111b-113b are brought close to each other successfully. Antenna characteristics can be improved.

  In the present embodiment, the first antenna element 111, the second antenna element 112, and the third antenna element 113 are formed on the same antenna base 151. Thereby, since the three antenna elements can be handled as one component, it is possible to contribute to the reduction of the number of components incorporated in the wireless device and the efficiency of the assembly of the wireless device. Further, as in the arrangement of the antenna elements according to the prior art as shown in FIG. 15, the second antenna element 912 may be formed on the circuit board 920, and the antenna characteristics of the second antenna element 912 may deteriorate. Absent.

  However, when the second antenna element 112 is disposed between the first antenna element 111 and the third antenna element 113, the second antenna element 112 is the first antenna element 111 and the third antenna element 113. It will be in a state surrounded by. For this reason, in the second frequency band, the second antenna element 112 is affected by shadowing due to being surrounded by the first antenna element 111 and the third antenna element 113, thereby causing the second antenna element 112. A new problem arises that the antenna characteristics deteriorate.

  Therefore, in the mobile radio terminal 100 according to the present embodiment, the first antenna element 111 and the third antenna element 113 are grouped together at the connection end 114, and the connection end 114 and the first matching unit 133 are combined. The frequency control means 150 for blocking the passage of the electric signal of the second frequency band is arranged between the two.

  FIG. 2 is a diagram illustrating a schematic configuration of the antenna 110 provided in the portable wireless terminal 100 according to the present embodiment. As shown in FIG. 2, in the antenna 110, the first antenna element 111 and the third antenna element 113 are connected by a connection end 114 to form one system, and the system of the second antenna element 112 is configured. In total, there are two feeding systems. Further, the frequency control means 150 is disposed between the connection end portion 114 and the first matching portion 133.

  FIG. 3 is a schematic diagram showing the configuration of the frequency control means 150 according to the present embodiment. As shown in FIG. 3, in this embodiment, a band elimination filter in which a coil 150a and a capacitor 150b are connected in parallel is used as the frequency control means 150. One end of the frequency control means 150 is connected to the connection end portion 114 via the first wiring 130, and the other end is connected to the first matching portion 133 via the first wiring 130.

  Here, the impedance of the frequency control means 150 is expressed by the following equation (1).

  In the above equation (1), Z is the impedance [Ω] of the frequency control means 150, L is the inductance [H] of the coil 150a, C is the capacitance [F] of the capacitor 150b, ω is the angular frequency [Hz], and j is an imaginary number. Respectively.

  In the above formula (1), the impedance Z is maximized when ω = √LC. That is, when ω = √LC, the inductivity of the coil 150a is equal to the capacitance of the capacitor, and a resonance phenomenon occurs in the frequency control means 150. The angular frequency ω is expressed by ω = 2πf where f is the frequency of the alternating current, and therefore the frequency at which the impedance Z is maximum, that is, the resonance frequency can be expressed by f = 1 / 2π√LC. .

Here, in the frequency control means 150, the inductance L of the coil 150a is preferably set so that the resonance frequency is included in the second frequency band, and preferably the resonance frequency and the center frequency of the second frequency band are substantially matched. The capacitance C of the capacitor 150b is determined.
For this reason, the frequency control means 150 operates so as not to pass the electric signal of the second frequency band because the impedance characteristic becomes very high in the second frequency band, that is, the resonance frequency f.

  On the other hand, in the first frequency band and the third frequency band, the frequency control unit 150 determines the values of the inductance L of the coil 150a and the capacitance C of the capacitor 150b so as to pass the electric signal. Of course, f = 1 / 2π√LC is satisfied as described above in determining L and C.

  By arranging the frequency control means 150 operating in this manner between the connection end portion 114 and the first matching portion 133, the first antenna element 111 and the third antenna element in the second frequency band. The electric signal of the second frequency band for 113 does not pass. For this reason, in the antenna 110 according to the present embodiment, the first antenna element 111 and the third antenna element 113 are equivalent to a state where the connection end portion 114 is disconnected (opened) in the second frequency band. For this reason, in the second frequency band, since the influence of shadowing of the first antenna element 111 and the third antenna element 113 surrounding the second antenna element 112 is suppressed, the second antenna element 112 Therefore, the deterioration of the antenna characteristics of the second antenna element 112 can be prevented.

  FIG. 4 is an image diagram for explaining pass characteristics of the frequency control means 150 according to the present embodiment, and shows a conceptual configuration in the second frequency band. As described above, the frequency control means 150 operates so as not to pass the electric signal of the second frequency band in the second frequency band. At this time, since the first antenna element 111 and the third antenna element 113 are connected at the connection end 114, the first tip 111a and the third tip 113a are connected as shown in FIG. One can assume a series of elements 116 to be open. Since the antenna characteristic of the second antenna element 112 depends on the electrical length of the adjacent element 116, the electrical length of each antenna element is as follows.

Since the first antenna element 111, the second antenna element 112, and the third antenna element 113 have the first, second, and third tip portions 111a to 113a open, respectively, the λ / 4 system Operates as a monopole antenna. Therefore, when the wavelength of the first frequency band is λ _L , the wavelength of the second frequency band is λ _M , and the wavelength of the third frequency band is λ _H , the electrical length of the first antenna element 111 is λ _L / 4. The electrical length of the second antenna element 112 is λ _M / 4, and the electrical length of the third antenna element 113 is λ _H / 4. The electrical length of the element 116 is (λ _L + λ _H ) / 4. As a premise, the frequency of the second frequency band is higher than that of the first frequency band, and the frequency band of the third frequency band is higher than that of the second frequency band. Since λ _L > λ _M > λ _H , λ _H / 2 <(λ _L + λ _H ) / 4 <λ _L / 2 holds. From this inequality, the electrical length (λ _L + λ _H ) / 4 of the element 116 is an open-ended element of the electrical length λ / 2 system in the fourth frequency band between the first frequency band and the third frequency band. Can think. When the fourth frequency band and the second frequency band are substantially equal, the element 116 operates as a non-excitation element for the second antenna element 112, and the element 116 contributes to antenna radiation. Further, even when the fourth frequency band is substantially the same as the second frequency, the antenna radiation of the second antenna element 112 is not inhibited and interference can be suppressed. In this embodiment, since the second frequency band is between the first frequency band and the third frequency band, the second frequency band and the fourth frequency band are substantially the same. The influence of inhibiting the radiation of the second antenna element 112 is small, and the antenna characteristics of the second antenna element can be suppressed. Thereby, the antenna characteristics of the second antenna element 112 can be improved.

  Next, the antenna gain of the antenna 110 according to the present embodiment will be described.

  FIG. 5 is a graph showing the frequency characteristics of the antenna gain of the second antenna element 112 according to this embodiment, and FIG. 5A shows the antenna gain of the second antenna element 112 with or without the frequency control means 150. FIG. 5B shows the amount of change in the antenna gain of the second antenna element 112 when the first antenna element 111 and the third antenna element 113 are used as non-excitation elements and when not used. ing.

  As shown in FIG. 5A, the antenna gain of the second antenna element 112 in the second frequency band of the antenna 110 is improved as compared with the case where the frequency control means 150 is not provided. This is because the influence of shadowing due to the first antenna element 111 and the third antenna element 113 surrounding the second antenna element 112 by the frequency control means 150 is suppressed. That is, in the second frequency band, the frequency control means 150 has very high impedance characteristics, so that the second antenna element 112 is less affected by shadowing of the first antenna element 111 and the third antenna element 113. Therefore, deterioration of antenna characteristics can be suppressed. Thus, since the interference with the 2nd antenna element 112 by the 1st antenna element 111 and the 3rd antenna element 113 is suppressed, degradation of the antenna characteristic of the 2nd antenna element 112 can be prevented.

Further, as shown in FIG. 5B, the total electrical length of the first antenna element 111 and the third antenna element 113 is approximately λ _M / 2 with respect to the wavelength λ _M of the second frequency band. When adjusted to be, the gain of the second antenna element 112 is further improved. This is because the first antenna element 111 and the third antenna element 113 operate as non-exciting elements with respect to the second antenna element 112. Thereby, the antenna characteristics of the second antenna element 112 can be improved.

  As described above, according to the portable wireless terminal 100 according to the present embodiment, the antenna of the second antenna element 112 is provided by arranging the frequency control means 150 between the connection end portion 114 and the first matching portion 133. The characteristics can be improved.

  As described above, according to the antenna 110 according to this embodiment, the first, second, and third tip regions 111c to 113c of the first, second, and third antenna elements 111 to 113 are all portable. The second antenna element 112 is disposed between the first antenna element 111 and the third antenna element 113, and is disposed at an end portion closer to the outer edge of the first casing 101 of the wireless terminal 100. The first, second, and third connection end portions 111b to 113b are all arranged at positions closer to the third tip portion 113a than to the first tip portion 111a.

  Furthermore, in the antenna 110 according to the present embodiment, the first connection end portion 111b and the third connection end portion 113b are grouped by the connection end portion 114, and the connection end portion 114 and the first connection end portion 114b are integrated. In this configuration, the frequency control unit 150 is disposed between the matching unit 133 and the first wiring 130. For this reason, in the second frequency band, since the electrical signal of the second frequency band does not pass between the connection end portion 114 and the first matching unit 133, the first antenna element 111 and the third antenna The effect of shadowing of the antenna element 113 is suppressed, and interference with the second antenna element 112 is suppressed. Thereby, deterioration of the antenna characteristics of the second antenna element 112 can be prevented.

  Furthermore, since the first antenna element 111 and the third antenna element 113 operate as non-exciting elements with respect to the second antenna element 112, the antenna characteristics of the second antenna element 112 can be improved.

  Therefore, according to the present embodiment, an antenna having three antenna elements can be realized that can obtain good characteristics even when each antenna element is used for the same system. it can.

(Modification)
FIG. 6 is a graph showing an example of pass characteristics of the frequency control means 150 according to the present embodiment. In the present embodiment, the case where a band elimination filter is used as the frequency control unit 150 has been described. However, as shown in FIG. 6, the frequency control unit 150 does not pass the electric signal of the second frequency band and does not pass the first signal. And it will not be specifically limited if it has the passage characteristic which lets the electric signal of the 3rd frequency band pass.

  FIG. 7 is a diagram illustrating a schematic configuration of a modified example of the antenna 110 according to the present embodiment. As shown in FIG. 7, the antenna 110a is the same as the antenna shown in FIG. 2 except that the frequency control means 155 is configured by a switch and the frequency control means 155 is excluded.

  FIG. 8 is a plan view showing a schematic configuration of the frequency control means 155 shown in FIG. As shown in FIG. 8, the frequency control unit 155 releases the connection position P <b> 1 that connects the connection end portion 114 and the first matching portion 133 and the connection between the connection end portion 114 and the first matching portion 133. It is configured to be switchable to the open position P2, and is controlled so as to be connected to the open position P2 during operation of the second frequency band, and to the connection position P1 during operation of the first frequency band and the third frequency band. Is done. The switch that is the frequency control means 155 may be in the direction opposite to that in FIG. Of course, in this case, during the second frequency band operation, the connection at the open end P2 and the connection end 114 side is disconnected by the switch to open connection, while the first frequency band and third frequency band operations are performed. It is sometimes controlled to be connected to the connection position P1.

  Thus, the antenna 110a can also realize an antenna that can obtain good characteristics when each antenna element is used for the same system in an antenna including three antenna elements.

  In the present embodiment, the configuration in which the frequency control means 150 is disposed between the connection end portion 114 and the first matching portion 133 has been described, but the present invention is not limited to this. For example, the frequency control means 150 may be separated and disposed in each of the first antenna element 111 and the third antenna element 113.

  FIG. 9 is a diagram illustrating a schematic configuration of another modification of the antenna 110 according to the present embodiment. As shown in FIG. 9, the frequency control means 156 is composed of a first frequency filter 156a and a second frequency filter 156b. The first frequency filter 156a is disposed between the first tip portion 111a and the connection end portion 114, and the second frequency filter 156b is disposed between the third tip portion 113a and the connection end portion 114. Be placed.

  As the first frequency filter 156a, for example, a low-pass filter that passes the first frequency band and does not pass the second frequency band can be used. On the other hand, the second frequency filter 156b can be a high-pass filter that does not pass the second frequency band but passes the third frequency band. Accordingly, the first frequency filter 156a and the second frequency filter 156b cause shadowing due to the second antenna element 112 being surrounded by the first antenna element 111 and the third antenna element 113 in the second frequency band. The influence of can be suppressed. Of course, a band pass filter that passes only the first frequency band may be used as the first frequency filter 156a. Further, as the second frequency filter 156b, a band pass filter that passes only the third frequency band may be used.

  Thus, the antenna 110b can also realize an antenna that can obtain good characteristics when each antenna element is used for the same system in an antenna including three antenna elements.

  Next, variations of the arrangement of the first, second, and third antenna elements 111 to 113 according to the above-described embodiment will be described in more detail with reference to FIGS. 17 and 18. FIGS. 17A to 17D and FIGS. 18A to 18F are views showing variations of the antenna assembly according to the present embodiment.

  As shown in FIG. 17A, the first, second and third tip regions 111c to 113c are arranged on the antenna base 115 at the end in the direction D1. Note that the “end portion” does not necessarily need to be the position of the boundary with the outside, and as shown in FIGS. 17B, 18D, and 18E, the first, second, and The third tip regions 111c to 113c may be slightly located inside. Further, as will be described later, the first, second, and third tip regions 111c to 113c do not need to be disposed at the end portion over the entire region, and at least one point is disposed at the end portion. Just do it.

  The first, second, and third connection end portions 111b to 113b are located on the third tip end portion 113a side with respect to the straight line D2 between the first tip end portion 111a and the third tip end portion 113a. doing. As shown in FIGS. 17C and 18F, the position in the direction orthogonal to the direction D1 may be shifted.

  As shown in FIGS. 18A to 18C, as long as the first, second, and third tip regions 111c to 113c are arranged at the end in the direction D1 on the antenna base 115, The 1st, 2nd and 3rd tip parts 111a-113a may be extended even to the position which removed from the end part concerned.

  The second antenna element 112 is disposed between the first antenna element 111 and the third antenna element 113. This is because, for example, in FIG. 14A, the second antenna element 112 is located on the straight line D2 in the direction D1 from the first antenna element 111, and the third antenna element is represented by the straight line D3. 113 is also shown because it is located in the direction D1 from the second antenna element 112.

  The first, second, and third antenna elements 111 to 113 are, for example, in-mold molding or insert molding in which a thin metal plate is processed into each antenna element shape and the antenna base 115 is fixed together. It can also be formed by a so-called manufacturing method.

  Further, as described above, the first, second, and third antenna elements 111 to 113 are preferably formed on the antenna base 115, but the antenna base 115 can be omitted. For example, the first, second, and third antenna elements 111 to 113 may be created in an FPC (Flexible printed circuit), and the FPC may be attached to the inside of a housing case that incorporates the antenna or to a fixing resin. As shown in FIG. 17 (d), the first, second, and third antenna elements 111 to 113 are formed of sheet metal having a three-dimensional shape, and are placed inside a housing case that incorporates the antenna. You may make it the structure which affixes.

  As described above, if the first, second, and third antenna elements 111 to 113 are at least spatially arranged as described above, the first, second, and third antenna elements 111 to 113 are used. Is within the scope of the present invention, regardless of how it is formed and fixed.

[Second Embodiment]
Another embodiment (second embodiment) of the present invention will be described with reference to FIGS. In addition, the same member number is attached | subjected to the member similar to 1st Embodiment, and the description is abbreviate | omitted.

  FIG. 10 is a diagram illustrating a schematic configuration of the antenna 210 according to the present embodiment. In the antenna 210 according to this embodiment, the frequency control unit 250 is disposed between the radio unit circuit 121 and the first matching unit 133. This point is different from the antenna 110 according to the first embodiment. As shown in FIG. 10, when the frequency control unit 250 is arranged between the radio unit circuit 121 and the first matching unit 133, between the radio unit circuit 121 and the first matching unit 133 in the second frequency band. The electric signal in the second frequency band is prevented from passing. Thereby, since the influence of shadowing due to the second antenna element 112 being surrounded by the first antenna element 111 and the third antenna element 113 is suppressed, the interference to the second antenna element 112 is suppressed. . Thereby, deterioration of the antenna characteristics of the second antenna element 112 can be prevented.

  When the frequency control means 250 is disposed between the radio unit circuit 121 and the first matching unit 133, the portion including the first antenna element 111, the third antenna element 113, and the first matching unit 133 is The impedance characteristics in the second frequency band are higher than the impedance characteristics in the first and third frequency bands. Typically, the impedance of the portion including the first antenna element 111, the third antenna element 113, and the first matching unit 133 is adjusted to be the maximum impedance in the second frequency band.

  FIG. 11 is an example of a Smith chart showing the frequency characteristics of the impedances of the first antenna element 111, the third antenna element 113, and the first matching unit 133, as viewed from the first matching unit 133 side according to the present embodiment. is there. As shown in FIG. 11, the impedances of the first antenna element 111, the third antenna element 113, and the first matching unit 133 as seen from the first matching unit 133 side approach an open state in the second frequency band. . The frequency characteristics of the impedances of the first antenna element 111, the third antenna element 113, and the first matching unit 133 as viewed from the first matching unit 133 side are FIG. 11, and the first matching unit 133 and the radio unit By loading the frequency control means 250 that does not pass the electric signal of the second frequency band between the circuit 121 and the electric circuit of the second frequency band between the radio circuit 121 and the first matching unit 133. Can be prevented from passing through.

  As described above, according to the present embodiment, the frequency control unit 250 prevents the electric signal in the second frequency band from passing between the radio unit circuit 121 and the first matching unit 133. Thereby, deterioration of the antenna characteristics of the second antenna element 112 can be prevented.

  Therefore, according to this embodiment as well, in an antenna having three antenna elements, it is possible to realize an antenna that can obtain good characteristics when each antenna element is used for the same system.

  FIG. 12 is a diagram illustrating a schematic configuration of a modified example of the antenna 210 according to the present embodiment. Like the antenna 210 shown in FIG. 12, the switch shown in FIG. 8 may be used as the frequency control means 255. Since the frequency control means 255 has been described in the first embodiment, the description thereof is omitted here.

  FIG. 13 is a diagram illustrating a schematic configuration of another modified example of the antenna 210 according to the present embodiment. A phase shifter may be used as the frequency control means 257 as in the antenna 210b shown in FIG. Any known phase shifter can be used as long as it is an element that changes the phase of an electric signal.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

  The following comparative experiment was performed on the antenna characteristics of the portable wireless terminal 100 according to the first embodiment.

  As an antenna of Example 1, an antenna was prepared in which the frequency control means 150 was disposed between the connection end portion 114 and the first matching portion 133 shown in FIG. Moreover, the band elimination filter shown in FIG. 3 was used for the frequency control means 150 of the antenna of the first embodiment. The inductive inductance L of the band elimination filter coil was 10 nH, the capacitive inductance C of the capacitor was 1.2 pF, and the resonance frequency was about 1450 MHz.

  As an antenna of the second embodiment, an antenna 110a in which a switch is arranged as a frequency control unit 155 between the connection end portion 114 and the first matching portion 133 shown in FIG.

  Further, as Comparative Example 1, the frequency control means is not disposed between the connection end portion 114 and the first matching portion 133, and the connection end portion 114 and the first matching portion 133 are connected by the first wiring 130. Prepared antenna.

  Using Example 1, Example 2, and Comparative Example 1 having such a configuration, the average gain of the second antenna element 112 in the second frequency band was measured.

  FIG. 14 is a graph showing the average gain in the second frequency band measured in the comparative experiment. As shown in FIG. 14, the average gain of the second antenna element 112 of Example 1 and Example 2 was measured higher than that of Comparative Example 1. This is because the frequency control means 150 and 155 are arranged, so that the electric signal in the second frequency band does not pass between the connection end 114 and the first matching part 133 in the second frequency band. This is because the influence of shadowing caused by the first antenna element 112 being surrounded by the first antenna element 111 and the third antenna element 113 can be suppressed, so that interference with the second antenna element 112 is suppressed. Thereby, deterioration of the antenna characteristics of the second antenna element 112 is prevented.

  On the other hand, in Comparative Example 1, since the second antenna element 112 is affected by shadowing due to being surrounded by the first antenna element 111 and the third antenna element 113, It is considered that interference occurred and the average gain of the second antenna element was lowered as compared with the first and second embodiments.

  From the above comparative experiments, it has been proved that the antenna according to the embodiment can significantly reduce the deterioration of the antenna characteristics of the second antenna element 112 in the second frequency band.

  INDUSTRIAL APPLICABILITY The present invention can be suitably used in the field of manufacturing antennas generally used for radio communication, in particular, antennas for portable radio terminals and radio apparatuses equipped with the antennas.

DESCRIPTION OF SYMBOLS 100 Portable radio | wireless terminal 101 1st housing | casing 102 2nd housing | casing 103 Connecting member 110 Antenna 110a Antenna 110b Antenna 111 1st antenna element 112 2nd antenna element 113 3rd antenna element 111a Tip part 112a Tip part 113a Tip portion 111b Connection end portion 112b Connection end portion 113b Connection end portion 114 Connection end portion 111c First tip region 112c Second tip region 113c Third tip region 115 Antenna base 116 Element 120 Circuit board 121 Wireless Circuit 122 Camera (metal member)
130 1st wiring 131 2nd wiring 133 1st matching part (matching circuit)
134 Second matching unit (matching circuit)
150 frequency control means 155 frequency control means 155a coil 155b capacitor 156 frequency control means 156a first frequency filter 156b second frequency filter 210 antenna 250 frequency control means 255 frequency control means 257 frequency control means 900 portable wireless terminal 901 first Housing 902 Second housing 903 Connecting member 911 First antenna element 912 Second antenna element 913 Third antenna element 915 Antenna base 920 Circuit board 921 Cellular communication radio circuit 922 Camera 923 GPS radio circuit

Claims (10)

A first antenna element operating in a first frequency band; a second antenna element operating in a second frequency band higher than the first frequency band; and a third frequency higher than the second frequency band. A third antenna element operating in a band, and an antenna built in a portable wireless terminal ,
The first, second, and third antenna elements are first, second, and third connection end portions that are ends on the side connected to the radio circuit, and the first, second, and third connection portions, respectively. A first end, a second end, and a third end, which are ends opposite to the end for use,
The second antenna element is disposed between the first antenna element and the third antenna element,
The first, second, and third connection end portions are all disposed closer to the third tip portion than the first tip portion,
A first wiring and a second wiring for connecting to the radio unit circuit;
The first wiring is connected to the first and third connection ends,
The second wiring is connected to the second connection end,
The first wiring includes a frequency control means for blocking an electric signal in the second frequency band ;
Each of the first, second and third antenna elements further includes first, second and third tip regions including first, second and third tip portions,
The first, second, and third tip regions are all disposed at end portions in a certain direction of the antenna. When projected onto a certain plane, the shadow of the second antenna element, according to claim 1, characterized in that that挿Ma is in the shadow of the shadow of the first antenna element a third antenna element antenna. The antenna according to claim 1 or 2 , wherein the first connection end portion and the third connection end portion are one. A matching circuit for matching the first and third antenna elements on the first wiring;
The first wiring, and the first and third connecting end, in a portion connecting the該整case circuit, claim 1-3, characterized in that said frequency control means are provided The antenna according to one item. The electrical lengths of the first and third antenna elements are such that the first and third antenna elements operate as non-excited elements that are electromagnetically coupled to the second antenna element that operates in the second frequency band. The antenna according to claim 4 , wherein a total is set. 6. The antenna according to claim 5 , wherein the total electrical length of the first and third antenna elements is approximately ½ of the wavelength corresponding to the second frequency band. A matching circuit for matching the first and third antenna elements on the first wiring;
The frequency control means is provided in a portion of the first wiring connecting the matching circuit and the radio unit circuit,
The first and third antenna element and the portion consisting of該整case circuit, the impedance at the second frequency band, according to claim 1 to 3, characterized in that higher than the impedance at the first and third frequency bands The antenna as described in any one. The frequency control means includes any one selected from the group consisting of a band elimination filter, a low pass filter, a high pass filter, a band pass filter, a switch, a PIN diode, an FET, a MEMS, and a phase shifter. Item 8. The antenna according to any one of Items 1 to 7 . The antenna according to any one of claims 1 to 8 , wherein the first, second and third antenna elements are formed on the same antenna base. Comprising the antenna according to any one of claims 1 to 9 and the radio unit circuit;
A portable radio terminal characterized in that the first, second and third antenna elements are all connected to the radio circuit.

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