JP5294067B2 - antenna - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wearable antenna which is widened in band and reducible in size. <P>SOLUTION: A conductive sheet has base line slits, inclined slits and additional slits. By this, the wearable antenna reducible in size can be obtained. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an antenna that is formed of a thin and flexible conductive material and can be appropriately attached to clothing.

  In portable electronic devices having a wireless communication function, an antenna is often attached to the device body. However, in order to make it easy to carry, it is required to reduce the size of the device. However, as the size of the device is reduced, the antenna must be reduced in size. As a result, the antenna sensitivity is inevitably deteriorated due to the miniaturization of the antenna.

  Recently, as one means for preventing deterioration of antenna sensitivity due to downsizing of an antenna, a structure in which an antenna is configured separately from a portable electronic device and the antenna is worn has been developed (patent) References 1, 2). These antennas are usually called wearable antennas.

  Qualitatively, this type of wearable antenna tends to obtain higher sensitivity as the antenna becomes larger, and is considered suitable for higher sensitivity compared to an antenna that must be attached to the apparatus body.

  Furthermore, since the wearable antenna is a structure to be worn and is not affected by the downsizing of the portable electronic device, the degree of freedom of the size and shape of the antenna is greater than when the antenna is attached to the portable device body. There is an advantage that. For example, the wearable antenna often employs a structure that can be easily attached to a wearable item such as clothes, and a configuration is considered so that the wearable antenna can be worn without a sense of incongruity for the user. In addition, even when the wearable antenna has a large size, a configuration that does not feel difficult to carry is directed.

  Non-Patent Document 1 discloses a broadband antenna that is installed indoors and receives a digital terrestrial television. The disclosed broadband antenna is configured by a plate-like antenna in which a main slit is provided in a predetermined direction on a planar conductor plate. Furthermore, Non-Patent Document 1 discloses a plate antenna in which a T-shaped slit is formed by a main slit and an auxiliary slot that intersects the main slit at a right angle. As described above, the plate-like antenna formed with the T-shaped slit can change the frequency-VSWR characteristic by adjusting the length and width of the auxiliary slot.

  Non-Patent Document 2 points out that when the above-described T-shaped slit is applied to a wearable antenna, unnecessary radiation increases, and it is difficult to construct a small antenna with a wide band. In order to improve this, Non-Patent Document 2 discloses a wearable antenna in which an umbrella-shaped or arrow-shaped slit is provided on a flexible conductive sheet.

Special Table 2003-516011 JP-T-2004-518322

IEICE Transactions B Vol. J90-B No. 7, pp. 679-688 "Development of small broadband antenna for digital terrestrial television" (2007) Hira, Iwasaki et al. “A Study on Wearable Slot Antennas” 2008 IEICE General Conference March B-1-128

  Patent Documents 1 and 2 disclose a planar inverted F-type patch antenna having two layers arranged at intervals in the thickness direction and a bridge portion that electrically short-circuits the two layers. A wearable antenna is constituted by the type patch antenna. However, in order to attach the planar inverted F-type patch antenna shown in Patent Documents 1 and 2 to clothing or the like, there is a drawback that the installation location is determined to some extent due to the thickness of the antenna. Furthermore, in the case of the antenna shown in Patent Document 2, it has a large size suitable for use in a wide place such as the back and front of the upper body of the human body. Thus, the large size of the antenna is due to the low frequency of the antenna used. However, there are also front-opening type clothing such as jackets and Y-shirts, and the antenna location is limited to the back. As the antenna placement location, it is not preferable that the placement location is limited by the type of clothes. Therefore, it is necessary to reduce the size to a size that can be attached to the human body. Furthermore, since the shape is generally complicated when the size is reduced, there is also a problem that the edge portion is easily broken when the conductive cloth is processed.

  On the other hand, Non-Patent Document 1 is an indoor antenna that receives a digital terrestrial television, and does not consider the wearable antenna. For this reason, the plate-shaped antenna provided with the T-shaped slit shown in Non-Patent Document 1, that is, the planar antenna, is not suggested for problems or the like when it is mounted on a human body.

  Furthermore, the wearable antenna provided with the umbrella-shaped slit shown in Non-Patent Document 2 can reduce unnecessary radiation. However, Non-Patent Document 2 does not consider the downsizing and further widening of the wearable antenna.

  The present invention provides a small antenna having a structure that can be applied even to a complicated shape, and can be attached to a portion having a small space or a portion having a complicated shape.

  According to the present invention, a planar conductive sheet having flexibility, and a slit formed in the conductive sheet, the slit extending in a predetermined direction inside the conductive sheet, and the base line An inclined slit connected to the conductive sheet at one end of the slit and inclined with respect to the baseline slit, and an additional slit extending in parallel with the baseline slit in the predetermined direction and shorter than the baseline slit. An antenna characterized by containing is obtained.

  Furthermore, according to the present invention, it comprises a planar conductive sheet having flexibility and a slit formed in the conductive sheet, the slit extending in a predetermined direction inside the conductive sheet; It is connected within the conductive sheet at one end of the baseline slit, and includes an inclined slit inclined with respect to the baseline slit and an additional slit formed from the outside to the inside of the conductive sheet. Is obtained.

  According to the present invention, it is possible to have a structure that is small (a part having a small space can be mounted) and can be applied to a complicated shape. Since slits are provided on the upper side and / or lower side of the conductive sheet, by providing slits on the upper side and / or lower side part where the current distribution becomes strong, the electrical length is gained by the slit part, and the overall It can be reduced in size. In addition, since the resonance by the slit portion and the resonance by the current flowing through the upper side and the lower side of the conductive material pattern are combined, a broadband wearable antenna or a dual-band wearable antenna can be provided.

It is a figure which shows the state which mounted | wore with the antenna which concerns on the 1st Embodiment of this invention. (A) And (B) is the top view and side view of an antenna which respectively concern on the 1st Embodiment of this invention. (A) and (B) are diagrams showing current distributions when the antenna shown in FIG. 2 is fed at 520 MHz and 770 MHz, respectively, and schematically explain the operating principle of the antenna shown in FIG. It is a figure for doing. It is a figure which shows the VSWR-frequency characteristic in the antenna shown by FIG. FIG. 3 is a diagram showing VSWR-frequency characteristics when the width of the lower additional slit is changed in the antenna shown in FIG. 2. (A) And (B) is respectively the top view and side view of an antenna which concern on the 2nd Embodiment of this invention. It is a top view which shows the antenna which concerns on the 1st modification of this invention. It is a top view which shows the antenna which concerns on the 2nd modification of this invention. It is a top view which shows the antenna which concerns on the 3rd modification of this invention. It is a top view which shows the antenna which concerns on the 4th modification of this invention. It is a top view which shows the antenna which concerns on the 5th modification of this invention.

  With reference to FIG. 1, the use state of the antenna which concerns on the 1st Embodiment of this invention is demonstrated. As shown in FIG. 1, the antenna is a wearable antenna 10 that is used while being worn on clothes. A wearable antenna 10 according to the present invention shown in FIG. 1 is attached to a garment (here, a front-opening shirt 12). In this example, the wearable antenna 10 is mounted on the surface of the front-opening shirt 12 in the vicinity of one side of the abdomen, but it may be a back abdomen, an arm, or a back. 1 shows an example in which the wearable antenna 10 is mounted on the shirt 12, but the wearable antenna 10 may be sewn on the cloth of the shirt 12, or a part of the shirt 12 may be attached to the wearable antenna 10. You can also Furthermore, it can be worn on trousers, skirts, hats other than clothes, etc., or can be a part thereof.

  The illustrated wearable antenna 10 according to the present invention includes a feeding point 14 for receiving and feeding power, as shown in FIG. 2, and the feeding point 14 is connected to an RF circuit (not shown) via a transmission line. The RF circuit is connected to a mobile phone or the like. For this reason, the illustrated wearable antenna 10 is connected to the portable terminal device together with the RF circuit, the transmission line, and the like.

  2A and 2B, there are shown a plan view and a side view of the wearable antenna 10 according to the first embodiment of the present invention. As shown in FIG. 2 (B), the wearable antenna 10 is formed by an adhesive material layer 22 and a conductive sheet 20 attached on the adhesive material layer 22. The material layer 22 is adhered to the shirt 12. The conductive sheet 20 described above can be substituted with a flexible printed circuit board (FPC) or a commonly used printed circuit board. In particular, a glass epoxy substrate (FR-4) or a Teflon (registered trademark) substrate can be used as a generally used substrate. These substrates can be used as a material that has sufficient flexibility and can be bent by setting the thickness to about 0.2 mm. Depending on the application, when flexibility is not required, a printed circuit board having a large thickness, for example, about 1 mm may be used.

  The adhesive material layer 22 only needs to have adhesiveness on at least one surface, and is usually attached before the conductive sheet 20 is processed. The adhesive material layer 20 may be formed of a thermocompression-bonding sheet or a hook-and-loop fastener, or may be formed of a chemically adhesive material. In addition, when the wearable antenna 10 is sewn on clothes such as the shirt 12, the adhesive material layer 22 is unnecessary.

  The wearable antenna 10 according to the first embodiment of the present invention shown in FIG. 2A includes a base (lower side), an upper side facing the base, and two sides facing each other connecting the base and the upper side. The conductive sheet 20 has a rectangular shape composed of sides. The lengths of the bottom and top sides define the width of the wearable antenna 10, and the lengths of the side sides define the height of the wearable antenna 10. As a material of the conductive sheet 20, for example, a natural fiber such as cotton, wool, silk, or a material layer in which a conductive material is attached to a chemically synthesized fiber such as polyester or acrylic, or a conductive thread-like material is used. Can be sewn into a cloth. In the illustrated example, the length in the width direction defined by the bottom side and the top side is 180 mm, and the height defined by the length of the side side is 160 mm.

  The illustrated wearable antenna 10 has a configuration in which a slit is provided in the conductive sheet 20, and the wearable antenna 10 has a feature in the configuration of the slit. That is, the illustrated slit is provided substantially at the center in the width direction of the conductive sheet 20, and is connected to the base line slit 24 extending from the bottom side to the top side direction, that is, the height direction, and the base line slit 24. Two inclined slits 26 and 28 inclined with respect to the slit 24 are provided. The illustrated baseline slit 24 forms an open end that is open on the bottom side and has a top (tip) that is short-circuited on the opposite side of the open end.

On the other hand, the inclined slits 26 and 28 are inclined at an acute angle with respect to the base line slit 24 in the base direction, and here, the umbrella-shaped part substantially inclined in the base direction at an angle of 45 ° with respect to the base line slit 24. Is configured. Accordingly, the illustrated slit forms an arrow-shaped or umbrella-shaped slit by the base line slit 24 and the inclined slits 26 and 28. The two inclined slits 26 and 28 may be called umbrella-shaped portions.

  The illustrated baseline slit 24 has a height of 135 mm and a slit width of 5 mm, while the inclined slits 26 and 28 have a length of 70 mm and a slit width of 5 mm. As a result, the distance between the top of the baseline slit 24 and the upper side of the conductive sheet 20 (that is, the short-circuit width) is 25 mm.

  The slit shown in FIG. 2A is further provided with lower additional slits (cuts) 30 having a length of 50 mm and a width of 10 mm on both sides of the base side open end of the baseline slit 24. 30 is open to the bottom side of the conductive sheet 20. The lower additional slit 30 only needs to have a width of about 1/9 to 1/3 of the width of the conductive sheet 20.

  On the other hand, in the illustrated example, on the upper side of the conductive sheet 20, the length of the conductive sheet 20 between the base line slit 24 and the inclined slits 26 and 28 is limited to 30 mm in length and 5 mm in width. These upper additional slits 32 are provided, and both the upper additional slits 32 are open to the upper side of the conductive sheet 20. In this embodiment, the lower additional slit 30 and the upper additional slit 32 are formed in a straight line substantially parallel to the base line slit 24. However, the present invention is not limited to this, but is a polygonal line or a curved line. May be provided. Moreover, the front-end | tip part of the lower addition slit 30 and the upper addition slit 32 can take arbitrary shapes, such as not only a square but circular shape and a triangular shape.

  Furthermore, at the intermediate portion in the height direction of the baseline slit 24, the power feeding unit 14 is connected to the conductive sheets 20 on both sides sandwiching the baseline slit 24. Specifically, for example, the central conductor of the coaxial cable is connected to the conductive sheet 20 on one side that sandwiches the baseline slit 24, and the outer conductor of the coaxial cable is the conductive sheet on the other side of the baseline slit 24. 20. In addition, the connection position of the power supply unit 14 was obtained at the best characteristics at a position that was 3/4 of the length of the base line slit 24 or a position in the vicinity thereof from the open end side of the base line slit 24. Note that an RF circuit of the mobile terminal device is connected to the other end of the coaxial cable connected to the power supply unit 14.

  As described above, the wearable antenna 10 according to the first embodiment of the present invention in which the lower and upper additional slits 30 and 32 are provided so as to sandwich the umbrella-type slit (24, 26, 28) includes only the umbrella-type slit. It has been experimentally confirmed that the size can be reduced as compared with a wearable antenna provided with no additional slit.

  Actually, the wearable antenna 10 having a size of 180 mm × 160 mm shown in FIG. 2A is equivalent to a wearable antenna provided with only an umbrella-shaped slit (arrow-shaped slit) using a conductive sheet of 240 mm × 130 mm. Or better.

  As described above, since the antenna according to the first embodiment of the present invention can be downsized, there is an advantage that it can be mounted in a small space and can be mounted on a portion having a complicated shape. Although not shown, the same characteristics were obtained by rounding the four corners of the conductive sheet 20 shown in FIG. Therefore, the conductive sheet 20 shown in FIG. 2 may have a substantially rectangular shape or a shape similar to a rectangle.

  Next, the operation principle of the wearable antenna according to the first embodiment of the present invention will be described with reference to FIG.

  This antenna is a composite antenna composed of two antennas: a half-wave dipole antenna formed of a conductive sheet 20 divided into left and right by an arrow-shaped slit, and a notch antenna formed of arrow-shaped slits 24, 26, and 28. The resonance of the conductive sheet 20 in the width direction is ½ wavelength, and the resonance by the baseline slit 14 provided at the lower center of the conductive sheet is used to achieve two resonances, thereby widening the antenna bandwidth. It is the structure which aimed at conversion. When the illustrated wearable antenna 10 is fed from the feeder 14, the left and right sides of the conductive sheet 20 across the baseline slit 24 operate as a planar half-wave dipole antenna, and the length of the baseline slit 24 And resonance corresponding to the matching element occurs. Here, the umbrella-shaped slits 26 and 28 function as matching elements that adjust the impedance of the power feeding unit.

  Further, in the example shown in FIG. 2A, upper and lower additional slits 30 and 32 are provided in addition to the umbrella-shaped slit described above. Thus, by providing the upper and lower additional slits 30 and 32, the electrical length of the current flowing through the conductor sheet 20 can be increased. As a result, even if the width dimension is reduced, a desired resonance frequency can be obtained. The electromagnetic wave which it has can be radiated. Therefore, the wearable antenna 10 shown in FIG. 2A can be reduced in size in the width direction from 240 mm to 180 mm as compared with an antenna having only an umbrella slit.

  As is clear from the above, the wearable antenna 10 shown in FIG. 2A has a resonance frequency determined by the width of the conductive sheet 20 and the additional slits 30 and 32. Thus, the wearable antenna 10 shown in the figure has two resonance frequencies, and a wideband antenna can be configured by making both resonance frequencies different.

  With reference to FIGS. 3A and 3B, the operation of the antenna according to the first embodiment of the present invention will be described. 3A and 3B are simulation results showing the distribution of current flowing through the conductive sheet 20 when the wearable antenna 10 shown in FIG. 2 is driven at 520 MHz and 770 MHz.

  As shown in FIG. 3A, when power is supplied at a low frequency of 520 MHz in the UHF band, the upper side of the conductive sheet 20 forming the wearable antenna 10 bypasses the two upper additional slits 32 formed on the upper side. The current C1 flows from left to right in the figure. On the other hand, the current C2 also flows from the left to the right in the figure so as to bypass the two lower additional slits 30 on the bottom side of the conductive sheet 20, and the currents C1 and C2 flowing up and down are in the same phase. As a result, electromagnetic waves are emitted. Since the currents C <b> 1 and C <b> 2 bypass the slits 30 and 32, respectively, the electrical length is secured, and the resonance frequency can be low with respect to the width dimension of the conductive sheet 20.

  On the other hand, as shown in FIG. 3B, when power is supplied at a high frequency of 770 MHz in the UHF band, the current C5 flows along the baseline slit 14 to operate as an antenna and to the inclined slots 26 and 28. The impedance is adjusted by the current C6 flowing along.

  Referring to FIG. 4, the VSWR-frequency (MHz) characteristic of wearable antenna 10 shown in FIG. 2 is shown by curve Ca. Here, if the VSWR is 2 or less, the antenna has good characteristics. Therefore, it can be seen that the wearable antenna 10 having resonance frequencies near 520 MHz and 770 MHz has good characteristics in the UHF band.

  Referring to FIG. 5, VSWR-frequency characteristics when the length of each lower additional slit 30 provided in the wearable antenna 10 shown in FIG. 2 is changed are shown. Here, when the length of each lower additional slit 30 is changed to 30, 40, 50, and 60 mm while the length of the conductive sheet 20 is maintained at 180 mm (ie, 1/6 to 1/3). Is shown).

  Curves Ca1, Ca2, Ca3, and Ca4 shown in FIG. 5 show the VSWR-frequency characteristics when the length of the lower additional slit 30 is 30 mm, 40 mm, 50 mm, and 60 mm, respectively. It can be seen that the resonance frequency tends to shift to the lower frequency side as the length of the signal becomes longer.

  With reference to FIGS. 6A and 6B, an antenna according to a second embodiment of the present invention will be described. The illustrated antenna is a wearable antenna 10a as in FIG. 2, and as shown in FIG. 6 (A), the conductive sheet 20a has an elliptical shape. This is different from the wearable antenna 10 shown in FIG. In other words, the wearable antenna 10a shown in FIG. 6A is provided with the base line slit 24, the inclined slits 26 and 28, the lower additional slit 30, and the upper additional slit 32 in FIG. 2A. This is the same as the wearable antenna 10.

  As shown in FIG. 6B, the wearable antenna 10a according to the second embodiment includes an elliptical conductive sheet 20a and an elliptical adhesive material layer 22a. In this example, a thin cloth (fabric) 221 is attached to the adhesive material layer 22a, and a plurality of Velcro tapes (registered trademark) 222 are provided on the surface of the fabric 221 opposite to the adhesive material layer 22a. Is attached. This facilitates the wearing of the wearable antenna 10a.

  In this case, the area of the fabric 221 can be wider than that of the conductive sheet 20a and the adhesive material layer 22a. Further, a configuration in which the fabric portion is wrapped around an arm or the like and fixed with Velcro (registered trademark) 222 is also possible.

  Also in this embodiment, the operation principle is the same as that of the first embodiment. Since the conductive sheet 20a has a curved peripheral shape of the conductive sheet 20a, the directivity due to the currents on the upper side and the lower side can be adjusted. Moreover, the freedom degree about the design property of appearance can be raised.

  Next, a modified example of the present invention will be described.

  Referring to FIG. 7, a wearable antenna 10b constituting an antenna according to a first modification of the present invention is shown. The illustrated wearable antenna 10b includes the base line slit 24 and the inclined slits 26 and 28 in the same manner as in FIG. 2A, and includes only the upper additional slit 32. Thus, the antenna is different from the antenna shown in FIG. 2A in that the lower additional slit is not provided.

  The wearable antenna 10b having this configuration can also reduce the width of the conductive sheet 20.

  Referring to FIG. 8, a wearable antenna 10c constituting an antenna according to a second modification of the present invention is shown. The illustrated wearable antenna 10c includes only a lower additional slit 30 and includes an upper additional slit. Not. With this configuration, the same operating characteristics as in FIG. 7 can be obtained, and the size in the width direction can be reduced.

  Referring to FIG. 9, a wearable antenna 10d according to a third modification of the present invention is shown. The wearable antenna 10 d is different from the wearable antenna 10 shown in FIG. 2A in that only one oblique slit 26 is connected to the base line slit 24. On the other hand, it is the same as FIG. 2A in that lower and upper additional slits 30 and 32 are provided.

  Referring to FIG. 10, a wearable antenna 10e according to a fourth modified example of the present invention includes a lower and upper additional slits 30 and 32 provided on a conductive sheet 20, and an inclined slit 26 and an umbrella-shaped portion. 28, but is different from other open embodiments and modifications in that the bottom side portion (lower side portion) of the base line slit 24a is short-circuited.

  Referring to FIG. 11, a wearable antenna 10f according to a fifth modification of the present invention is different from other embodiments and modifications in that a Y-shaped slit is formed instead of an umbrella-shaped slit. Yes. As shown in the drawing, the Y-shaped slit includes a base line slit 24 and two inclined slits 26 a and 28 a extending upward with respect to the base line slit 24. In other words, the two illustrated inclined slits 26 a and 28 a have an obtuse angle of 90 ° or more with respect to the baseline slit 24. The inclined slits 26a and 28a may each have an obtuse angle of 90 ° or more and the other an acute angle of 90 ° or less with respect to the baseline slit 24.

  In any of the wearable antennas described above, the adhesive material is stacked under the conductive material before processing, so that the shape can be maintained without fraying even when the processing is performed in a stacked state.

  In addition, the antenna according to the present invention may be used as a single antenna, but this antenna includes an RF circuit mounted on the conductive sheet or an electronic device including the RF circuit, and a ground portion of the transmission line. It is desirable to have connection means for conducting with the conductive material. For example, by covering the transmission line with a conductive material for ground conduction, the conductive material for ground conduction and the conductive material conductor may be electrically connected to the conductive material by a conductive adhesive material for ground conduction. . Thereby, the shielding performance of the transmission line is enhanced, and incoming radio waves can be prevented from being directly coupled to the transmission line.

  In the above-described embodiment, the case where a wearable antenna is used as a transmission antenna has been described, but it goes without saying that the wearable antenna can also be used as a reception antenna.

  In the present invention, a wearable antenna that can be reduced in size in a wide band is provided by providing an additional slit together with a baseline slit and an inclined slit in a flexible planar conductive material suitable for being worn on the body's underwear. it can.

  Hereinafter, embodiments of the present invention will be listed.

  According to the first aspect of the present invention, a planar conductive sheet having flexibility and a slit formed in the conductive sheet, the slit extending in a predetermined direction inside the conductive sheet. A slit, an end of the base line slit connected to the conductive sheet, an inclined slit inclined with respect to the base line slit, extending in parallel to the base line slit in the predetermined direction, and from the base line slit An antenna characterized by including a short additional slit.

  According to a second aspect of the present invention, in the first aspect, the base line slit has an open end that is open to the outside of the conductive sheet on the opposite side of one end connected to the inclined slit, The additional slit has a pair of open end side additional slits provided on both sides of the open end side of the baseline slit, thereby obtaining an antenna.

  According to a third aspect of the present invention, there is provided the antenna according to the second aspect, wherein the additional slit further includes a pair of inclined slit side additional slits provided on the inclined slit side. can get.

  According to a fourth aspect of the present invention, in the first aspect, the baseline slit has an open end that is open to the outside of the conductive sheet on the opposite side of the one end connected to the inclined slit, The additional slit has a pair of inclined slit side additional slits provided on the inclined slit side, thereby obtaining an antenna.

  According to the fifth aspect of the present invention, in any one of the first to fourth aspects, an antenna is obtained in which the additional slit forms an open end.

  According to a sixth aspect of the present invention, in any one of the first to fifth aspects, an antenna is provided that includes a power feeding portion provided at an intermediate portion of the baseline slit.

  According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the conductive sheet has any one of a rectangular shape, an elliptical shape, and a shape similar thereto. Thus, an antenna characterized by the above can be obtained.

  According to an eighth aspect of the present invention, in any one of the first to sixth aspects, the inclined slit is two umbrella-shaped inclined slits provided at an acute angle with respect to a predetermined direction in which the baseline slit extends. It is possible to obtain an antenna characterized by the following.

  According to a ninth aspect of the present invention, in any one of the first to sixth aspects, the inclined slit is two obtuse angled inclined slits provided at an obtuse angle with respect to a predetermined direction in which the baseline slit extends. An antenna characterized by being present is obtained.

  According to a tenth aspect of the present invention, in any one of the first to sixth aspects, an antenna is obtained, wherein the inclined slit is a linear inclined slit extending to one side with respect to the baseline slit. It is done.

  According to an eleventh aspect of the present invention, in the first aspect, an antenna is obtained in which the baseline slit is short-circuited at the end opposite to the inclined slit side.

  According to a twelfth aspect of the present invention, a planar conductive sheet having flexibility and a slit formed in the conductive sheet, the slit extending in a predetermined direction inside the conductive sheet. A slit, an inclined slit that is connected to one end of the base line slit in the conductive sheet, is inclined with respect to the base line slit, and an additional slit that is formed from the outside to the inside of the conductive sheet. An antenna characterized by being

  According to a thirteenth aspect of the present invention, in the twelfth aspect, an antenna is obtained in which the additional slit has any one of a semicircular shape, a square shape, and a triangular shape.

  According to a fourteenth aspect of the present invention, there is provided the antenna according to any one of the first to thirteenth aspects, wherein the antenna has an adhesive material layer provided on one surface of the conductive sheet. can get.

  According to a fifteenth aspect of the present invention, in the sixth aspect, a wireless communication circuit or an electronic device including a wireless communication circuit mounted on the conductive sheet, and between the wireless communication circuit and the power feeding unit There is obtained an antenna characterized by having a transmission line for connecting the transmission line and a connection means for conducting a ground portion of the transmission line with the conductive material.

  According to the sixteenth aspect of the present invention, a planar conductive sheet, a baseline slit formed in the conductive sheet and having one end open, and an umbrella formed in an umbrella shape at the other end of the baseline slit. An antenna provided with a slit, provided outside the umbrella slit, having a short-circuit portion that short-circuits the baseline slit, and further provided with an incision in the conductive sheet. can get.

  According to a seventeenth aspect of the present invention, in the antenna according to the sixteenth aspect, an antenna is obtained in which the conductive material has flexibility.

  According to an eighteenth aspect of the present invention, there is provided the antenna according to the sixteenth or seventeenth aspect, wherein the short-circuit portion has a width approximately equal to or less than the slit width.

  According to the nineteenth aspect of the present invention, a mobile terminal device including the antenna described in any of the first to eighteenth aspects is obtained.

10, 10a-10f Wearable antenna 12 Shirt 14 Feeding point 20 Conductive sheet 24 Baseline slits 26, 28, 26a, 28a Inclined slit 30 Lower additional slit 32 Upper additional slit

Claims (21)

A planar conductive sheet having flexibility formed by a cloth-like material obtained by sewing a material layer in which a conductive material is adhered to fibers or a conductive thread-like material, and formed on the conductive sheet. The slit is connected to the inside of the conductive sheet at one end of the baseline slit, and is inclined with respect to the baseline slit. An antenna comprising: a slit; and an additional slit extending in the predetermined direction in parallel with the base line slit and shorter than the base line slit.   In Claim 1, the said baseline slit has the open end opened to the exterior of the said electroconductive sheet in the opposite side to the one end connected with the said inclination slit, The said additional slit is the said open end side of the said baseline slit. An antenna having a pair of open end side additional slits provided on both sides.   3. The antenna according to claim 2, wherein the additional slit further includes a pair of inclined slit side additional slits provided on the inclined slit side.   2. The pair of base lines according to claim 1, wherein the base line slit has an open end opened to the outside of the conductive sheet on the opposite side of one end connected to the inclined slit, and the additional slit is provided on the inclined slit side. An antenna having an additional slit side additional slit.   5. The antenna according to claim 1, wherein the additional slit forms an open end.   6. The antenna according to claim 1, further comprising a power feeding portion provided at an intermediate portion of the baseline slit.   7. The antenna according to claim 1, wherein the conductive sheet has any one of a rectangular shape, an elliptical shape, and a shape similar to the rectangular shape.   7. The antenna according to claim 1, wherein the inclined slit is two umbrella-shaped inclined slits provided at an acute angle with respect to a predetermined direction in which the baseline slit extends.   The antenna according to any one of claims 1 to 6, wherein the inclined slits are two obtuse angle inclined slits provided at an obtuse angle with respect to a predetermined direction in which the baseline slit extends.   In any one of Claims 1-6, the said inclination slit is two obtuse angle inclination slits provided with the acute angle and the other at an obtuse angle with respect to the predetermined direction where the said base line slit extends, It is characterized by the above-mentioned. antenna.   7. The antenna according to claim 1, wherein the inclined slit is a single linear inclined slit that extends to one side with respect to the baseline slit.   The antenna according to claim 1, wherein the base line slit is short-circuited at an end opposite to the inclined slit side. A planar conductive sheet having flexibility formed by a cloth-like material obtained by sewing a material layer in which a conductive material is adhered to fibers or a conductive thread-like material, and formed on the conductive sheet. The slit is connected to the inside of the conductive sheet at one end of the baseline slit, and is inclined with respect to the baseline slit. An antenna comprising a slit and an additional slit formed from the outside to the inside of the conductive sheet. 13. The antenna according to claim 12, wherein the additional slit includes a tip portion having any one of a semicircular shape, a square shape, and a triangular shape. 15. The antenna according to claim 1, wherein the antenna is provided on one surface of the conductive sheet and can be attached to clothing .   The wireless communication circuit mounted on the conductive sheet or an electronic device including the wireless communication circuit, a transmission line connecting the wireless communication circuit and the power feeding unit, and a ground of the transmission line An antenna comprising a connecting means for electrically connecting a portion with the conductive material. A planar conductive sheet having flexibility, formed by a cloth-like material obtained by sewing a material layer in which a conductive material is adhered to fibers or a conductive thread-like material, and the conductive sheet A base slit formed at one end and an umbrella slit formed in an umbrella shape at the other end of the base slit, and a short-circuit portion provided outside the umbrella slit and short-circuiting the baseline slit And an additional slit is provided in the conductive sheet. The antenna according to any one of claims 1 to 17 , wherein the antenna is used in a UHF band of 500 MHz to 800 MHz . The antenna according to claim 18, wherein the additional slit has a length depending on a VSWR-frequency characteristic in the UHF band . The portable terminal device containing the antenna as described in any one of Claims 1-19. 18. The wearable antenna according to claim 17, further comprising an adhesive material layer that can be attached to clothing .

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