JP2007184883A - Multiple frequency antenna - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multiple frequency antenna capable of improving the flexibility of adjusting a plurality of frequency bands. <P>SOLUTION: The multiple frequency antenna includes a first antenna element 120 having a turned part 121 and wider width at the turned part 121, a second antenna element 110 having a conductor part 122 formed along the first antenna element 120 and connected to the first antenna element 120, and a parasitic element 130 formed separately from the first antenna element 120 along a conductor 112 of a feeding point 100a side of the first antenna element 120, and is configured so as to be able to independently set a resonance frequency by adjusting the end part or width of the turned part 121, the position 100b of a tip of the second antenna element 110 and the position of a tip of the parasitic element 130. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a multi-frequency antenna that can be used in a plurality of frequency bands.

  2. Description of the Related Art Conventionally, a mobile terminal device such as a communication mobile terminal has been developed with a multi-frequency antenna that can be shared in a plurality of frequency bands in order to support multiple functions and multiple communication methods. Specifically, there are a 900 MHz band and a 1800 MHz band used for a mobile phone, a 1570 MHz band for receiving signals from GPS, a 2400 MHz band used for Bluetooth, and the like.

  Here, it is known that even if an individual antenna element is adjusted so that it can be shared in a plurality of frequency bands by using one antenna, it is difficult to adjust each frequency band independently. That is, if the antenna element is adjusted to be suitable for one frequency band, a shift occurs in the other frequency band. An antenna with improved adjustment independence that can eliminate such difficulties has been reported (see, for example, Patent Document 1).

  FIG. 19 is a diagram illustrating a configuration of a multi-frequency antenna described in Patent Document 1. In FIG. 19, the multi-frequency antenna 1 is composed of a linear or belt-like conductor, and includes a first element 10d from a portion 10b where the conductor branches to a tip 10c of the linear conductor, and a portion 10b where the conductor branches. And a second element 10f up to the end 10e of the strip-shaped conductor. The multi-frequency antenna 1 has a configuration in which the elements 10d and 10f are folded.

Here, the effective length from the base end 10a to the tip 10c of the first element 10d is set to, for example, a quarter wavelength of the first frequency f1, and from the base end 10a to the tip 10e of the second element 10f. Is set to a quarter wavelength of the second frequency f2, for example. Thus, in the conventional multi-frequency antenna, the individual antenna elements 10d and 10f are adjusted for each frequency so as to ensure the independence of the adjustment.
JP-A-8-276537

  However, the conventional multi-frequency antenna can ensure the independence of adjustment for two frequency bands, but has a problem that it cannot be suitably applied to three or more frequency bands.

  The present invention has been made to solve such a problem, and an object of the present invention is to realize a multi-frequency antenna capable of improving the degree of freedom of adjustment with respect to a plurality of frequency bands.

  According to a first aspect of the present invention, there is provided a first antenna element having one or more folded portions, the width of which is widened by any one or more folded portions, and the first antenna element. A multi-frequency antenna comprising the formed antenna portion and the second antenna element connected to the first antenna element.

  According to a second aspect of the present invention, in the first aspect, the second aspect includes a parasitic element formed along a conductor on a feeding point side of the first antenna element away from the first antenna element. And

  According to a third aspect of the present invention, in the first or second aspect, the second antenna element is sandwiched between two conductors of the first antenna element connected via the folded portion. It is characterized by being formed in the region.

  According to a fourth aspect of the present invention, in the third aspect, two conductors connected via the folded portion are formed to be parallel to each other.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the fifth aspect is formed on a substrate having predetermined flexibility.

  According to a sixth aspect of the present invention, in any one of the first to fifth aspects, a resonance frequency is provided in the vicinity of one or more of the elements so that the resonance frequency can be adjusted within a predetermined range. The dielectric member is provided.

  According to a seventh aspect of the present invention, in the sixth aspect, the dielectric member is provided so as to surround at least a part of any one or more of the antenna elements formed on the flexible substrate. It is characterized by that.

  According to an eighth aspect of the present invention, in the sixth aspect, the dielectric member has an attachment portion for attachment to a housing.

  According to a ninth aspect of the present invention, in the eighth aspect, the attachment portion includes a columnar hole, a columnar protruding portion, a hole having a gradient in the depth direction, a protruding portion having a gradient in the protruding direction, and a hook. It consists of any one or more of these.

  According to a tenth aspect of the present invention, in the eighth aspect, the attachment portion includes a columnar hole so that the dielectric member can be screwed.

  According to an eleventh aspect of the present invention, in the eighth aspect, the attachment portion has a shape that can prevent the flexible substrate from rotating.

  According to a twelfth aspect of the present invention, in the sixth aspect, the dielectric member is provided in a portion in contact with the feeding point of the first antenna element, and electrically connected to the feeding point of the first antenna element. It has the electric power feeding terminal connected to.

  According to the present invention, since the width of the folded portion of the first antenna element is widened, the degree of freedom of adjusting the width of the folded portion is increased in addition to the freedom of adjusting the length of the antenna element. A multi-frequency antenna capable of improving the degree of freedom of adjustment can be realized. Moreover, since the parasitic element is provided along the first antenna element, the degree of freedom in adjustment can be further improved. Furthermore, by providing the dielectric member, the degree of freedom of adjustment can be further improved, and the workability of mounting the antenna can be improved.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(First embodiment)
FIG. 1 is a plan view of a multi-frequency antenna according to a first embodiment of the present invention. In FIG. 1, the multi-frequency antenna 100 includes a first antenna element 110 having a shape whose width is widened at the folded portion 111, and a conductor portion 122 formed along the first antenna element 110. The second antenna element 120 connected to the antenna element 110 and the parasitic element 130 formed along the conductor portion 112 on the feeding point 100a side of the first antenna element 110 are configured.

  Hereinafter, the first frequency band is, for example, 800 to 900 MHz band, the second frequency band is, for example, 1500 to 1850 MHz band, and the third frequency band is, for example, 1850 to 2500 MHz band. Further, the first frequency, the second frequency, and the third frequency are set as predetermined frequencies in the first frequency band, the second frequency band, and the third frequency band, respectively.

  Here, the first antenna element 110, the second antenna element 120, and the parasitic element 130 are formed on a predetermined substrate such as a circuit board. Here, the substrate is preferably a flexible substrate such as an FPC (Flexible Printed Circuit). In view of the recent reduction in space for storing multi-frequency antennas due to the multifunctional and miniaturization of portable terminal devices, the FPC that can be folded can be used with a thickness of about several tens of μm. At the same time, it can be placed in a slight gap, which is extremely preferable. As said FPC, what formed the copper film | membrane on resin, such as a polyimide and PET (PolyEthylene Terephthalate), can be used.

  For example, the first antenna element 110 may have a U-shape as shown in FIG. 1 and the width of the folded portion 111 may be widened. The conductor portions 112 and 113 connected to both ends of the folded portion 111 have a linear or strip shape. Here, the effective length from the feeding point 100a of the first antenna element 110 to the tip of the folded portion 111 is the frequency side with the lowest VSWR (Voltage Standing Wave Ratio) of the multi-frequency antenna 100 in the vicinity of the first frequency. (Hereinafter, this valley is referred to as the first valley, and the valley on the higher frequency side is referred to as the second and third valleys in order). Specifically, for example, the length is about ¼ wavelength of the target first frequency. Here, when the multi-frequency antenna 100 is formed on an FPC having a thickness of about several tens of μm, the above effective length may be made substantially equal to the actual length.

  The second antenna element 120 has, for example, an L-shape as shown in FIG. 1, and a conductor part 121 connected to the conductor part 112 of the first antenna element 110 and a conductor parallel to the conductor part 112. Part 122 may be included. The length of the second antenna element 120 is determined so that, for example, the third valley of the VSWR of the multi-frequency antenna 100 is located in the vicinity of the target third frequency.

  The parasitic element 130 is formed along the conductor on the feeding point 100a side of the first antenna element 110 as shown in FIG. 1, and the length is, for example, the second valley of the VSWR of the multi-frequency antenna 100. To be located in the vicinity of the second frequency.

  Hereinafter, a method for adjusting the resonance frequency will be described using the multi-frequency antenna having the shape shown in FIG. The multi-frequency antenna 200 shown in FIG. 2 is substantially equivalent to the multi-frequency antenna shown in FIG. 1 from the viewpoint of freedom of adjustment of the resonance frequency. 3 to 7 are diagrams showing VSWR curves when the positions of the points 200c, 200d, 200e, 200f, and 200b shown in FIG. 2 are changed. Here, in the diagrams shown in FIGS. 3 to 7, the resonance frequency in the first frequency band is substantially changed only as shown in FIG. 3. Further, only those shown in FIG. 4 have greatly changed the resonance frequency in the second frequency band. Furthermore, the resonance frequency in the third frequency band is greatly changed only as shown in FIGS.

  First, a method for adjusting the first resonance frequency to the first frequency will be described with reference to FIG. FIG. 3 shows a VSWR curve at each position when the position of the end portion 200c of the folded portion of the first antenna element 210 is changed by the distance lc in the direction shown in FIG. 2 by 1 mm with reference to the predetermined position. FIG. FIG. 3 shows that the first resonance frequency can be changed substantially independently over the width of 50 MHz by changing the position of the end portion 200c by a total of 5 mm. For this reason, the first resonance frequency of the multi-frequency antenna 200 is set in advance within a predetermined range, for example, within a range of ± 25 MHz centered on the first frequency, and the position of the end portion 200c is adjusted. Then, the first resonance frequency can be adjusted by adjusting the first resonance frequency to the first frequency.

  Similarly, a method for adjusting the second resonance frequency to the second frequency will be described with reference to FIG. FIG. 4 is a diagram showing a VSWR curve at each position when the position of the tip 200d of the parasitic element 230 is changed by the distance ld in the direction shown in FIG. 2 by 1 mm with respect to the predetermined position. FIG. 4 shows that the second resonance frequency can be independently changed over the width of 280 MHz by changing the position of the end portion 200d by a total of 4 mm. Therefore, as in the case of the first resonance frequency, the second resonance frequency of the multi-frequency antenna 200 is set in advance within a predetermined range, for example, within a range of ± 140 MHz centered on the second frequency. Then, the second resonance frequency can be adjusted by adjusting the position of the end portion 200d and adjusting the second resonance frequency to the second frequency.

  Similarly, a method for adjusting the third resonance frequency to the third frequency will be described with reference to FIGS. FIG. 5 shows a position corresponding to the inner portion of the folded portion 111 shown in FIG. 1 (hereinafter referred to as the folded portion) 200e by changing the distance le in the direction shown in FIG. It is a figure which shows the VSWR curve in each position at the time. Similarly, FIG. 6 is a diagram showing a VSWR curve at each position when the position of the tip 200f of the second antenna element 220 is changed by a distance lf in the direction shown in FIG. 2 by 1 mm with reference to a predetermined position. It is. Similarly, FIG. 7 is a diagram showing a VSWR curve at each position when the position of the tip 200b of the first antenna element 210 is changed by a distance lb in the direction shown in FIG. 2 by 1 mm with respect to a predetermined position. It is.

  FIG. 5 shows that the third resonance frequency can be independently changed over a width of 120 MHz by changing the position of the folded interior 200e of the first antenna element 210 by a total of 4 mm. Similarly, FIG. 6 shows that the third resonance frequency can be independently changed over a width of 120 MHz by changing the position of the tip 200f of the second antenna element 220 by a total of 4 mm. Further, FIG. 7 shows that the third resonance frequency can be independently changed over a width of 180 MHz by changing the position of the tip 200b of the first antenna element 210 by a total of 4 mm. For this reason, the third resonance frequency of the multi-frequency antenna 200 is set in advance within a predetermined range, for example, within a range of ± 90 MHz centered on the third frequency. By adjusting the position of any one or more of the tip 200b, the tip 200f of the second antenna element 220, and the folded interior 200e, and adjusting the third resonance frequency to the third frequency, The resonance frequency can be adjusted.

  In the above description, the multi-frequency antenna 100 having the shape constituted by the three antenna elements 110, 120, and 130 shown in FIG. 1 has been described. However, in a predetermined case such as when communication is not performed in the second frequency band. There is no need to form the parasitic elements in the arrangement shown in FIG. In this case, the second antenna element 120 shown in FIG. 1 may be provided outside the U-shaped region of the first antenna element 110. Also, as shown in FIG. 8, a plurality of folded portions may be provided, and in order to increase the degree of freedom of adjustment, the width may be increased so that the width of the plurality of folded portions can be adjusted.

  Furthermore, the range of adjustment of the portion of each antenna element that performs the above adjustment is not limited to the above, but is merely an example of the range of adjustment. In addition, the dimensions of each antenna element may be other dimensions such as a half wavelength for a dipole antenna, and the range of adjustment described above may be determined according to the dimensions and shape of the antenna.

(Second Embodiment)
FIG. 9 is a diagram for explaining the configuration of the multi-frequency antenna according to the second embodiment of the present invention. In FIG. 9, a multi-frequency antenna 500 is placed near one or more of elements 110, 120, and 130 on a multi-frequency antenna 101 (see FIG. 9A) formed on a flexible substrate 510. A dielectric member 520 provided so that the resonance frequency can be adjusted is added (see FIGS. 9B and 9C).

  The multi-frequency antenna 101 is formed by forming any of the multi-frequency antennas 100 to 400 of the first embodiment of the present invention on the flexible substrate 510 described in the first embodiment of the present invention. Yes. FIG. 9A shows a multi-frequency antenna 101 including a multi-frequency antenna 100 and a flexible substrate 510. Here, the multi-frequency antenna 101 may be formed with a predetermined protective film so as to cover the elements 110, 120, and 130.

  The dielectric member 520 is made of a material having a small dielectric loss (tan δ), such as an epoxy resin, a fluorine resin such as Teflon (registered trademark), an ABS (Acrylonitrile Butadiene Styrene Copolymer) resin, a polyamide resin such as nylon, or the like. In addition to a low dielectric constant resin having a relative dielectric constant of about 5 or less, a so-called fiber reinforced plastic in which carbon fiber or the like is mixed with a plastic, or a ceramic mixed resin in which a ceramic is mixed with a resin has a high relative dielectric constant of 5 or more. A dielectric constant functional material can be used. However, other dielectrics such as ceramic may be used.

  A dielectric having a relative dielectric constant of about 5 or less (hereinafter referred to as a low dielectric constant dielectric) is suitable for fine adjustment of antenna characteristics. In addition, a dielectric having a relative dielectric constant of 5 or more (hereinafter referred to as a high dielectric constant dielectric) is suitable for significant adjustment of antenna characteristics. In the example shown in FIGS. 9B and 9C, the dielectric member 520 is disposed so as to sandwich the region near the folded portion 111 of the first antenna element 110. However, the dielectric member 520 may be provided in other regions as necessary, or may be provided on one side of the flexible substrate 510.

  Hereinafter, a method for adjusting the resonance frequency will be described using a multi-frequency antenna in which the multi-frequency antenna 200 shown in FIG. 2 is formed on a flexible substrate and a dielectric member is attached. The multifrequency antenna 200 shown in FIG. 2 is substantially equivalent to the multifrequency antenna shown in FIG. 1 from the viewpoint of the degree of freedom of adjustment of the resonance frequency as described above.

  First, adjustment of the first resonance frequency will be described. FIG. 10 shows the dielectric constant dependence of the frequency characteristic of VSWR in a configuration in which a dielectric member is provided so as to sandwich the folded inside 200e of the first antenna element 210 (see FIG. 10B) (FIG. 10A). FIG. FIG. 10 shows that the resonance frequency of the first resonance frequency band can be independently changed over a width of about 50 MHz by changing the relative permittivity of the dielectric member to 18. For this reason, the first resonance frequency of the multi-frequency antenna 200 is set in advance within a predetermined range, for example, within a range of ± 25 MHz centered on the first frequency, and the relative permittivity of the dielectric member. The first resonance frequency can be adjusted by adjusting the first resonance frequency to the first frequency.

  Next, the adjustment of the second resonance frequency will be described. FIG. 11 shows the dielectric constant dependence of the frequency characteristic of VSWR in a configuration in which a dielectric member is provided so as to sandwich the tip portion of the parasitic element 230 (see FIG. 11B) (see FIG. 11A). FIG. FIG. 11 shows that the resonance frequency of the second resonance frequency band can be changed substantially independently over a width of about 500 MHz by changing the relative dielectric constant of the dielectric member to 18.

FIG. 12 shows a case where the contact area between a dielectric member having a relative dielectric constant of 4 and a flexible substrate having the same configuration as that shown in FIG. 11 is changed (see FIGS. 12B1 to 12B5). It is a figure which shows the dielectric constant dependence (refer Fig.12 (a)) of the frequency characteristic of VSWR. Said contact area takes the value of 0.12, 0.15, 0.165, 0.18, and 0.21 cm < ² > in order of FIG. 12 (b1)-(b5). From FIG. 12, by changing the contact area between the dielectric member and the flexible substrate in the range of 0.12 to 0.21 cm ² , the resonance frequency of the second resonance frequency band is substantially over a width of about 400 MHz. It can be seen that it can be changed independently.

  For this reason, the second resonance frequency of the multi-frequency antenna 200 is set in advance within a predetermined range, for example, within a range of ± 200 MHz centered on the second frequency, and the relative permittivity of the dielectric member. And the contact area can be adjusted, and the second resonance frequency can be adjusted. Note that the first and second resonance frequency adjusting methods of the present invention described above are not limited to implementations in which the relative dielectric constant and the contact area are changed, but also in implementations in which the shape of the dielectric is changed. The same applies.

  In addition, as shown in FIG. 13, by providing a dielectric member in the vicinity of the tip of the folded portion of the first antenna element 210, the first resonance frequency and the third resonance frequency can be changed to the low frequency side. it can. Further, as shown in FIG. 14, by providing a dielectric member closer to the base end, the second resonance frequency and the third resonance frequency are made one without changing the first resonance frequency, and another resonance is obtained. It can be a frequency.

(Third embodiment)
FIGS. 15-18 is a figure for demonstrating the dielectric material member which comprises the multifrequency antenna of the 3rd Embodiment of this invention. In FIG. 15, the dielectric member 521 has a mounting portion Cv for mounting the multi-frequency antenna to a housing such as a communication terminal device (not shown). Here, fixing members 621a and 621b are provided in the casing of the communication terminal device or the like, and at least one of the fixing members 621a and 621b has a shape corresponding to the attachment portion Cv and the multi-frequency antenna is connected to the casing. A fixing portion Cc that is fixed to is formed. FIG. 15 shows an example in which the attachment portion Cv has a hook shape and the fixing portion Cc has a corresponding concave shape. Here, the hook-like shape refers to a shape that can be hooked on a counterpart member, such as a jaw-like shape or a bowl-like shape. However, the attachment portion Cv may have a concave shape, and the fixing portion Cc may have a hook shape.

  In FIG. 16, the dielectric member 522 has an attachment portion H formed of a columnar hole for attaching the multi-frequency antenna to a housing such as a communication terminal device (not shown). Here, a fixing member 622 is provided in a housing of the communication terminal device or the like, and a columnar fixing portion R corresponding to the attachment portion H is formed on the fixing member 622. A slight gradient may be provided in a portion where the attachment portion H and the fixing portion R are fitted. Further, the reverse configuration, that is, the attachment portion may have a rod-like shape, and the fixing portion may include a correspondingly shaped hole. Furthermore, the structure which screws the dielectric material member 522 and the fixing member 622 may be sufficient. In this case, the mounting part consists of a columnar hole, the fixing part consists of a screw hole, and both the mounting part and the fixing part consist of through-holes. A configuration in which a screw is passed through the hole may be used.

  In FIG. 17, the dielectric member 523 has a pin-shaped attachment portion P having a stopper S for attaching the multi-frequency antenna to a housing such as a communication terminal device (not shown). Here, a fixing member having a concave portion having a corresponding shape is provided in a housing of the communication terminal device or the like, and the attachment portion P is attached to the fixing portion. By forming the stopper on the attachment portion P as described above, the flexible substrate can be prevented from rotating after the attachment portion P has attached the antenna. However, it is possible to use other shapes such as a shape deformed by crushing a cylinder in the radial direction, a shape deformed by crushing a cone in the radial direction, a polygonal cylinder, a polygonal pyramid, a flat plate shape, etc. It may be in a shape that can prevent this.

In FIG. 18A, the dielectric member 524 has a pin-like attachment portion Cp made of metal or the like that has high electrical conductivity and is easily elastically deformed. Here, a fixing member 624 provided with a fixing portion Hb having a concave portion having a corresponding shape is formed in a housing of the communication terminal device or the like. In the configuration shown in FIG. 18A, a through hole Ha is provided at a predetermined location in the vicinity of the feeding end of the first antenna element 110 on the flexible substrate 510, and the attachment portion Cp is fixed through the through hole Ha. The antenna element 110 is inserted into the part Hb and fixed to the fixing part Hb, and the antenna element 110 and a feed line (not shown) in the fixing part Hb are electrically connected. On the other hand, in the configuration shown in FIG. 18B, a feed line is formed on the surface of the fixing member 625, and the fitting portion of the dielectric member 525 is fitted to the fixing portion so that it is close to the feeding end of the first antenna element. The above power supply line is connected.

  The multi-frequency antenna of the present invention has the effect that the degree of freedom of adjustment for a plurality of frequency bands can be improved, and the multi-frequency antenna used in communication devices, portable terminal devices, etc. that perform communication in a plurality of frequency bands. It is useful as an antenna.

FIG. 1 is a plan view showing the configuration of the multi-frequency antenna according to the first embodiment of the present invention. FIG. 2 is a plan view showing a configuration of a multi-frequency antenna used for explanation of a method for adjusting a resonance frequency. FIG. 3 is a diagram showing a VSWR curve at each position when the position of the end portion 200c of the folded portion 211 of the first antenna element 210 is changed. FIG. 4 is a diagram illustrating a VSWR curve at each position when the position of the tip 200d of the parasitic element 230 is changed. FIG. 5 is a diagram showing a VSWR curve at each position when the position of the first antenna element 210 folded interior 200e is changed. FIG. 6 is a diagram illustrating a VSWR curve at each position when the position of the tip 200f of the second antenna element 220 is changed. FIG. 7 is a diagram showing a VSWR curve at each position when the position of the tip 200b of the first antenna element 210 is changed. FIG. 8 is a plan view of a multi-frequency antenna having another configuration of the present invention. FIG. 9 is a diagram for explaining the configuration of the multi-frequency antenna according to the second embodiment of the present invention. FIG. 10A is a diagram showing the dielectric constant dependency of the frequency characteristic of VSWR when a dielectric member is disposed at the position shown in FIG. FIG. 11A is a diagram showing the dielectric constant dependence of the frequency characteristic of VSWR when a dielectric member is disposed at the position shown in FIG. FIG. 12A is a diagram showing the dielectric constant dependence of the frequency characteristic of VSWR when a dielectric member is arranged at the position shown in FIGS. 12B1 to 12B5. FIG. 13A is a diagram showing the dielectric constant dependence of the frequency characteristic of VSWR when a dielectric member is arranged at the position shown in FIG. FIG. 14A is a diagram showing the dielectric constant dependency of the frequency characteristic of VSWR when a dielectric member is arranged at the position shown in FIG. FIG. 15 is a diagram for explaining a first example of a dielectric member constituting the multi-frequency antenna according to the third embodiment of the present invention. FIG. 16 is a diagram for explaining a second example of the dielectric member constituting the multi-frequency antenna according to the third embodiment of the present invention. FIG. 17 is a diagram for explaining a third example of the dielectric member constituting the multi-frequency antenna according to the third embodiment of the present invention. FIG. 18 is a diagram for explaining a fourth example of the dielectric member constituting the multi-frequency antenna according to the third embodiment of the present invention. FIG. 19 is a plan view showing a configuration of a conventional multi-frequency antenna.

Explanation of symbols

10, 100, 200, 300, 400 Multi-frequency antenna 10a Base end 10b Conductor branch point 10c First element tip 10d First element 10e Second element tip 10f Second element 100a, 200a Feed point 100b 200b First antenna element tip 101 Multi-frequency antenna 110, 210 formed on flexible substrate 110, first antenna element 111 Folded portion 112, 113 of first antenna element Conductor portion of first antenna element 120, 220 Second antenna elements 121, 122 Conductive portions 130, 230 of the second antenna element Parasitic element 200c End part 200d of the folded part Tip 200e of the parasitic element 200e Folding interior 200f of the first antenna element Antenna element tip 510 Flexible substrate 520, 521, 5 2,523,524,525 dielectric member 621a, 621b, 622,624,625 fixing member

Claims (12)

A first antenna element having one or more folded portions, the width of which extends at any one or more of the folded portions;
A multi-frequency antenna comprising: a conductor portion formed along the first antenna element; and the second antenna element connected to the first antenna element.   2. The multi-frequency antenna according to claim 1, further comprising a parasitic element formed along a conductor on a feeding point side of the first antenna element away from the first antenna element.   The said 2nd antenna element is formed in the area | region pinched | interposed into two conductors connected via the said folding | turning part of the said 1st antenna element, The Claim 1 or Claim 2 characterized by the above-mentioned. The described multi-frequency antenna.   The multi-frequency antenna according to claim 3, wherein two conductors connected via the folded portion are formed so as to be parallel to each other.   The multi-frequency antenna according to any one of claims 1 to 4, wherein the multi-frequency antenna is formed on a substrate having a predetermined flexibility.   The dielectric member provided so that a resonant frequency can be adjusted within a predetermined range in the vicinity of any one or more of the elements, The dielectric member according to any one of claims 1 to 5, Multi-frequency antenna.   The multi-frequency antenna according to claim 6, wherein the dielectric member is provided so as to surround at least a part of any one or more of the antenna elements formed on the flexible substrate.   The multi-frequency antenna according to claim 6, wherein the dielectric member has an attachment portion for attachment to a housing.   9. The mounting portion includes one or more of a columnar hole, a columnar protrusion, a hole having a gradient in the depth direction, a protrusion having a gradient in the protrusion direction, and a hook. The multi-frequency antenna described in 1.   The multi-frequency antenna according to claim 8, wherein the attachment portion is formed of a columnar hole so that the dielectric member can be screwed.   The multi-frequency antenna according to claim 8, wherein the attachment portion has a shape capable of preventing rotation of the flexible substrate.   The dielectric member has a feeding terminal provided at a portion in contact with the feeding point of the first antenna element and electrically connected to the feeding point of the first antenna element. The multi-frequency antenna described in 1.

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