JP3842963B2 - Antenna element - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an antenna element used for a portable telephone or a portable wireless communication device.
[0002]
[Prior art]
  In recent years, as portable telephones and portable wireless communication devices become more widespread, there is a demand for reduction in size and weight. Miniaturization of various electronic components such as semiconductor integrated circuits is rapidly progressing, but it is an antenna that hinders miniaturization of wireless communication devices. As is well known, the antenna is an entrance / exit of electromagnetic waves, and if the antenna is not resonated with the frequency to be used, the efficiency is extremely lowered. In the case of a normal dipole antenna, since it requires a length of ½ wavelength of the used frequency, it is very difficult to reduce the size. For this reason, various ideas regarding the miniaturization of the antenna have been proposed.
[0003]
  For example, in the antenna disclosed in Japanese Patent Laid-Open No. 10-13135, the antenna element is folded back so as to be substantially parallel along the longitudinal direction, and the shape of the antenna is reduced and the antenna resonates in two frequency bands. It is configured to do.
[0004]
  Further, in the antenna disclosed in Japanese Patent Laid-Open No. 10-229304, an antenna element is formed on the surface of a dielectric substrate so that it can be further reduced in size and can be easily mounted on a circuit board. Devised.
[0005]
[Problems to be solved by the invention]
  However, the increase and diversification of functions of portable wireless communication devices are desired, and in order to realize this, the number of parts often increases. For this reason, in order to reduce the size of the device, it is necessary to further reduce the size of the electronic component, particularly the antenna.
[0006]
  Furthermore, since a portable telephone uses a wide frequency band of an ultra high frequency band, an antenna having a usable wide frequency bandwidth is required.
[0007]
  In view of the above problems, an object of the present invention is to provide a small antenna element that can be mounted and used on a circuit board, and further to provide a small antenna element having a wide usable frequency bandwidth. is there.
[0008]
[Means for Solving the Problems]
  In order to achieve the above object, the present invention provides a belt-like conductor which is provided on the surface of a flat insulator and which is alternately folded to form a meandering antenna element, and a rear end of the antenna element. An external terminal connected to the antenna element, and the front end or the folded portion of the antenna element is located on the folded side with respect to the adjacent folded portion on the rear end side or the rear end of the antenna element, and the length of the antenna element Is set to a length that resonates at least to a predetermined first frequency within the first frequency band, and the conductor of the tip portion of the antenna element is formed wider than the conductor of the other portion. A device is proposed.
[0009]
  According to the antenna element, the lengths of the portions facing each other by folding the antenna element are shortened or folded back obliquely as approaching the tip of the antenna element, or the folded element is meandered, and the tip of the antenna element or The usable frequency bandwidth was expanded by configuring the folded portion so that it is located on the folded side with respect to the adjacent folded portion on the rear end side or the rear end of the antenna element. Furthermore, since the width of the conductor at the tip of the antenna element is wider than the width of other parts, a capacitance is generated between the conductor at the tip and the surrounding ground conductor. The antenna element constitutes a head capacity antenna by the electrostatic capacity. This shortens the length of the antenna element that resonates with the first frequency.
[0010]
  Further, in claim 2, an antenna element according to claim 1 is proposed in which adjacent folded conductors are arranged in parallel to each other.
[0011]
  According to the antenna element, the conductors of the antenna element are arranged so that the adjacent folded conductors are parallel to each other.
[0012]
  According to a third aspect of the present invention, there is proposed an antenna element according to the first aspect in which another flat insulator is laminated on the surface of the flat insulator so as to sandwich the conductor.
[0013]
  According to the antenna element, since the conductor is a laminated element sandwiched between flat insulators, the conductor is not exposed to the outside, so that unnecessary short circuit of the conductor during use is prevented. .
[0014]
  In claim 4,An element body formed by laminating a plurality of insulator layers having conductors provided on the surface, and provided on the outer surface of the element bodyConfigure the power feeding unitWith external terminalAn external terminal for grounding provided on the outer surface of the element body;The predetermined layer of conductor forms the antenna element.The antenna element is a band-shaped conductor that connects the tip conductor and the grounding external terminal, and a tip conductor that is located at the tip of the antenna element and has a wider width than other parts. And a strip-shaped branch conductor having one end connected to a predetermined position of the strip-shaped conductor and the other end connected to an external terminal constituting the power feeding unit, and the branch conductor and the strip-shaped conductor Is set at a position where the impedance at the external terminal constituting the power feeding unit matches a predetermined power feeding point impedance.An antenna element is proposed.
[0015]
  According to the antenna element, since the conductor constituting the antenna element is laminated via the insulator layer, the area when the element is mounted on the parent circuit board can be reduced. further,The antenna element constitutes an antenna generally called an inverted F type,Since the width of the conductor at the tip portion of the antenna element is formed wider than the width of the other portion, a capacitance is generated between the conductor at the tip portion and the ground conductor around the conductor, The antenna element constitutes a head capacity type antenna by electrostatic capacity. This shortens the length of the antenna element that resonates with the first frequency.
[0016]
  According to a fifth aspect of the present invention, there is provided an element body formed by laminating a plurality of insulator layers provided with a conductor on the surface, an external terminal constituting a power feeding portion provided on the outer surface of the element body, and the element. A grounding external terminal provided on the outer surface of the body, a conductor of a predetermined layer forms an antenna element, and the antenna element is located at the tip of the antenna element and wider than the other parts A leading end conductor having a width; a strip-shaped conductor connecting the leading end conductor and the grounding external terminal; one end connected to a predetermined position of the strip-shaped conductor and the other end serving as the power feeding unit; And a length of the antenna element is set to a length that resonates with a predetermined first frequency in a first frequency band. A branched conductor and the strip-shaped conductor; Connection point proposes the antenna element impedance of the external terminals constituting the power supply portion is set at a position that matches the predetermined feed point impedance.
[0017]
  According to the antenna element, since the conductor constituting the antenna element is laminated via the insulator layer, the area when the element is mounted on the parent circuit board can be reduced. Further, the antenna element constitutes an antenna generally referred to as an inverted F type, and the width of the conductor at the tip portion of the antenna element is formed wider than the width of the other portion. Capacitance is generated between the portion of the conductor and the surrounding ground conductor, and the antenna element constitutes a head capacity antenna by the capacitance. This shortens the length of the antenna element that resonates with the first frequency.
[0018]
  According to claim 6, there is proposed the antenna element according to claim 5, wherein the strip conductor is connected in series via via holes so as to be alternately folded into a plurality of different layers. To do.
[0019]
  According to the antenna element, since the band-shaped conductor is folded, the conductors facing each other are electrically coupled to each other and resonate with a second frequency in a second frequency band different from the first frequency band. The second frequency band can also be used. Further, by adjusting the distance between the conductors of each layer, that is, the thickness of the insulator layer, etc., the electrical coupling state between these conductors is changed to change between the first frequency band and the second frequency band. The interval can be changed.
[0020]
  Also,Claim 7ThenAn element body formed by laminating a plurality of insulator layers each having a conductor provided on the surface; And an external terminal provided on the outer surface of the element body,Forming the antenna elementOf a given layerThe first conductor has a strip shape, and the antenna elements are formed in series via via holes so that the first conductors of different layers are alternately folded, and the rear end of the antenna element is connected to the external terminal. The front end of the first conductor in each layer forming the antenna element is connected to the front end of the conductor rather than the rear end of the conductor connected to the rear end of the conductor. And the length of the antenna element is set to a length that resonates at least with a predetermined first frequency within the first frequency band.The conductor at the tip of the antenna element has a wider width than the other parts.Proposed antenna element.
[0021]
  According to the antenna element, since the conductors divided in the length direction of the antenna element are arranged in different layers, the area when the element is mounted on the parent circuit board is reduced. Further, in the antenna element, the lengths of the first conductors of the respective layers facing each other by folding the antenna element are shortened or folded obliquely toward the tip of the antenna element, or the first conductors of the respective layers are meandered. In addition, the usable frequency bandwidth can be expanded by configuring the antenna element so that the front end of the antenna element or the folded via-hole connection part is located on the folded side of the adjacent folded part on the rear end side or the rear end of the antenna element. did.
[0022]
  Also,Claim 8ThenClaim 7The antenna element according to claim 1, wherein the first conductor is disposed at a position where electrical coupling is generated between the first conductors of different layers, and the antenna element is arranged at the first peripheral edge number. In addition to the above, an antenna element set to resonate also at a predetermined second frequency in a second frequency band different from the first frequency band is proposed.
[0023]
  According to the antenna element, the first conductors of different layers are arranged at positions where electrical coupling occurs with each other, so that the antenna element can be used so as to generate resonance also in the first and second frequency bands. . In addition, the electrical coupling degree between the first conductors can be easily adjusted by changing the shape and arrangement of the first conductors in each layer and the thickness and dielectric constant of the insulator layer. Thereby, the first and second frequencies, the frequency bandwidth, and the like can be easily adjusted.
[0024]
  Also,Claim 9ThenAn element body formed by laminating a plurality of insulator layers having conductors provided on the surface, a first external terminal constituting a power feeding portion provided on the outer surface of the element body, and an outer surface of the element body A second external terminal for grounding provided, having a predetermined area provided in a predetermined layer and connected to the first external terminal.First conductor forming an antenna elementAnd the first conductorAgainstOne end isA strip-shaped second conductor for capacitive coupling is provided, and the second conductorIs connected to the second external terminal.ConnectedAndLength of the second conductorThe first conductor is the first conductorAn antenna element set to a length that resonates with a predetermined first frequency within one frequency band is proposed.
[0025]
  According to the antenna element,The first conductor has an area suitable for electromagnetic radiation,When the capacitance between the first conductor and the second conductor increases, the frequency bandwidth including the resonance frequency is widened and the resonance frequency tends to decrease. In the above configuration, it is possible to easily adjust the capacitance by changing the capacitance in the capacitive coupling, and it is possible to easily set the resonance frequency and the frequency bandwidth to desired values.
[0026]
  Also,Claim 10ThenClaim 9In the antenna element described inThe second conductor is provided in the same layer as the layer in which the first conductor is disposed.An antenna element is proposed.
[0027]
  According to the antenna element, the firstBy changing the distance between the conductor and the second conductor and the length of the second conductor, the first conductor serving as the antenna element resonates with the first frequency f1 within the first frequency band to be used. Set to
[0028]
  In an eleventh aspect, there is proposed an antenna element according to the ninth aspect, wherein the second conductor is provided in a layer different from a layer in which the first conductor is disposed.
[0029]
  According to the antenna element, when the capacitance between the first conductor and the second conductor increases, the frequency bandwidth including the resonance frequency is widened and the resonance frequency tends to decrease. In the above configuration, the capacitance of the capacitive coupling is changed by changing the thickness and dielectric constant of the insulator layer between the first conductor and the second conductor and the arrangement of the first conductor and the second conductor. The resonance frequency and the frequency bandwidth can be easily set to desired values.
[0030]
  Also,Claim 12ThenClaim 11In the antenna element described in 1), an antenna element in which the second conductor is provided in each of two layers sandwiching the layer in which the first conductor is provided is proposed.
[0031]
  According to the antenna element, capacitance can be obtained between the second conductor provided in two layers and the first conductor, so that the area of the capacitive coupling portion can be reduced. Since the distance between the first conductor and the second conductor can be increased, the distance can be adjusted more easily than the minute distance, and the resonance frequency and frequency bandwidth can be easily adjusted. It can be carried out.
[0032]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0033]
  FIG. 1 is an external perspective view showing an antenna element according to the first embodiment of the present invention, and FIG. 2 is a plan view thereof. In the figure, reference numeral 10A denotes an antenna element, and conductors 12a to 12e for forming an antenna element 12 are provided on the upper surface of an insulating flat substrate (hereinafter simply referred to as a substrate) 11 made of a dielectric ceramic material. In addition, an external terminal 13 constituting a power feeding unit is formed on one side surface of the substrate 11.
[0034]
  Although not shown, a plurality of dummy electrodes are formed on the back surface of the substrate 11 so as to be stably soldered and fixed when mounted on the parent circuit board.
[0035]
  The antenna element 12 includes strip-shaped conductors 12a, 12c, and 12e arranged in parallel to each other and strip-shaped conductors 12b and 12d that form folded portions, and these conductors 12a to 12e are connected in series. The total length is set to a length that resonates with the first frequency f1 in the first frequency band to be used.
[0036]
  One end of the conductor 12a in the longitudinal direction is connected to the external terminal 13, and the other end is connected to one end of the conductor 12c via a conductor 12b having a length L1b forming a folded portion. The conductor 12a and the conductor 12c are arranged in parallel so as to face each other, and the length L1a of the conductor 12a is set longer than the length L1c of the conductor 12c.
[0037]
  The other end in the longitudinal direction of the conductor 12c is connected to one end of the conductor 12e via a conductor 12d having a length L1d that forms a folded portion. The conductor 12c and the conductor 12e are arranged in parallel so as to face each other, and the length L1c of the conductor 12c is set longer than the length L1e of the conductor 12e. The width of the conductor 12e corresponding to the tip of the antenna element 12 is set wider than the width of the other conductors 12a to 12d.
[0038]
  As a result, the other end of the conductor 12e corresponding to the tip of the antenna element 12 is positioned on the turn-back side with an interval of a length L2 from the adjacent turn-up portion, that is, the conductor 12b.
[0039]
  According to the antenna element having the above configuration, the shape of the antenna element 10A can be formed small, so that the mounting area on the parent circuit board can be reduced, and the electronic device can be downsized.
[0040]
  In addition, the conductors 12a to 12e forming the antenna element 12 are folded back so as to be parallel, and the lengths of the conductors 12a, 12c, and 12e facing each other are shortened toward the tip of the antenna element 12, thereby reducing the antenna element 12. Since the tip end or the folded portion is formed so as to be located closer to the folded side than the adjacent folded portion on the feeding point side or the feeding point of the antenna element, the usable frequency bandwidth is expanded.
[0041]
  The measurement results are shown in FIG. In FIG. 3, the vertical axis represents reflection loss (return loss), and one scale thereof represents 10 dB. The horizontal axis represents the frequency, and one scale thereof represents 100 MHz. A curve A is a characteristic curve of the antenna element 10A, and a curve B is an antenna characteristic curve having a configuration in which the tip of the antenna element is extended to the same position as the adjacent folded portion as in the conventional case. Thus, according to the present embodiment, the usable bandwidth can be expanded in the first frequency band to be used as shown by the characteristic curve A.
[0042]
  In addition, since the width of the conductor 12e at the tip end portion of the antenna element 12 is formed wider than the width of the conductors 12a to 12d in other portions, a capacitance is generated between the conductor 12e and the surrounding ground conductor. Then, the antenna element 12 constitutes a head capacity type antenna by this electrostatic capacity. Thereby, the length of the antenna element 12 resonating at the first frequency f1 can be shortened.
[0043]
  In addition, since the antenna element 12 is configured to be folded back, the conductors facing each other are electrically coupled to each other, so that the second frequency f2 in the second frequency band different from the first frequency band also resonates. It can also be used in bands. Further, by adjusting the lengths L1b and L1d of the conductors 12b and 12d constituting the folded portion, that is, the intervals between the conductors 12a, 12c and 12e facing each other, the first frequency band and the second frequency band The interval between can be varied.
[0044]
  Next, a second embodiment of the present invention will be described.
[0045]
  FIG. 4 is a plan view showing an antenna element according to the second embodiment. In the figure, the same components as those of the first embodiment described above are denoted by the same reference numerals and description thereof is omitted. Further, the difference between the antenna element 10B of the second embodiment and the first embodiment is that the wide conductor 12e corresponding to the tip of the antenna element 12 and the conductors 12b and 12d in the folded portion are excluded. That is, the conductors 12a and 12c are made to meander. Thus, by making the conductors 12a and 12c meander, the length of the antenna element 12 can resonate with the first frequency within a small area. Therefore, since the shape of the antenna element 10B can be formed small, the mounting area on the parent circuit board can be reduced as compared with the conventional case.
[0046]
  Next, a third embodiment of the present invention will be described.
[0047]
  FIG. 5 is a plan view showing an antenna element according to the third embodiment. In the figure, the same components as those of the first embodiment described above are denoted by the same reference numerals and description thereof is omitted. The difference between the antenna element 10C of the third embodiment and the first embodiment is that the number of times the antenna element 12 is folded is set to four.
[0048]
  That is, the antenna element 12 is composed of strip-shaped conductors 12a, 12c, 12e, 12g, and 12i arranged in parallel with each other and strip-shaped conductors 12b, 12d, 12f, and 12h that form folded portions, and these conductive elements. The bodies 12a to 12i are formed by being connected in series, and the total length thereof is set to a length that resonates with the first frequency f1 in the first frequency band to be used.
[0049]
  One end of the conductor 12a in the longitudinal direction is connected to the external terminal 13, and the other end is connected to one end of the conductor 12c via a conductor 12b forming a folded portion. The conductor 12a and the conductor 12c are arranged in parallel so as to face each other, and the length of the conductor 12a is set longer than the length of the conductor 12c.
[0050]
  The other end of the conductor 12c in the longitudinal direction is connected to one end of the conductor 12e via a conductor 12d that forms a folded portion. The conductor 12c and the conductor 12e are arranged in parallel so as to face each other, and the length of the conductor 12c is set longer than the length of the conductor 12e.
[0051]
  The other end in the longitudinal direction of the conductor 12e is connected to one end of the conductor 12g via a conductor 12f that forms a folded portion. The conductor 12e and the conductor 12g are arranged in parallel so as to face each other, and the length of the conductor 12e is set longer than the length of the conductor 12g.
[0052]
  The other end in the longitudinal direction of the conductor 12g is connected to one end of the conductor 12ei via a conductor 12h forming a folded portion. The conductor 12g and the conductor 12i are arranged in parallel so as to face each other, and the length of the conductor 12g is set longer than the length of the conductor 12i.
[0053]
  The width of the conductor 12i corresponding to the tip of the antenna element 12 is set wider than the widths of the other conductors 12a to 12h.
[0054]
  The same effect as that of the first embodiment can be obtained even when the structure is folded three times or more like the above-described structure.
[0055]
  Next, a fourth embodiment of the present invention will be described.
[0056]
  FIG. 6 is a plan view showing an antenna element according to the fourth embodiment. In the figure, the same components as those of the first embodiment described above are denoted by the same reference numerals and description thereof is omitted. The difference between the antenna element 10D of the fourth embodiment and the first embodiment is that another substrate 11 is laminated and integrated so as to cover the conductors 12a to 12e on the upper surface of the substrate 11. is there.
[0057]
  Thus, since the conductors 12a-12e which comprise the antenna element 12 are arrange | positioned so that it may be pinched | interposed into the two board | substrates 11, since the conductors 12a-12e are not exposed to the external field, the conductors 12a-12e at the time of use are used. Unnecessary short circuit is prevented.
[0058]
  Next, a fifth embodiment of the present invention will be described.
[0059]
  FIG. 7 is an external perspective view showing an antenna element according to the fifth embodiment, and FIG. 8 is an exploded perspective view thereof. In the figure, reference numeral 20A denotes an antenna element. Conductor patterns 22a to 22c for forming an antenna element 22 are provided on the upper surface of an insulating substrate 21 made of a dielectric ceramic material. Further, conductors 22a to 22c are formed on the upper surface of the substrate 21. An element body in which similar substrates 21 are laminated and integrated so as to sandwich 22c is formed. Furthermore, an external terminal 23 </ b> A and a grounding external terminal 23 </ b> B constituting a power feeding unit are formed on each of two adjacent side surfaces of the two stacked substrates 21.
[0060]
  Although not shown, a plurality of dummy electrodes are formed on the back surface of the lower substrate 21 so as to be stably soldered and fixed when mounted on the parent circuit substrate.
[0061]
  The conductor 22a constituting the antenna element 22 has a substantially square shape having a predetermined area for radiating electromagnetic waves, and has a predetermined width and length so as to be connected to the center of one side and the grounding external terminal 23B. A conductor 22b is provided. The length of the conductor 22b is set so that the antenna element 22 resonates at the first frequency f1 within the first frequency band to be used. Furthermore, a conductor 22c having a predetermined width and length is provided so as to be connected to the external terminal 23A from a predetermined position in the length direction of the conductor 22b. The position of the connection point (branch point) between the conductor 22b and the conductor 22c is such that the impedance of the external terminal 23A serving as the feeding point matches the impedance of the high-frequency input / output unit in the parent circuit using the antenna element 20A. Is set. That is, by changing the position of the connection point (branch point) between the conductor 22b and the conductor 22c, the impedance at the external terminal 23A serving as a feeding point changes.
[0062]
  According to the antenna element 20A having the above configuration, an antenna generally referred to as an inverted F type is configured. Further, since the conductor 22a of the antenna element 22 has a predetermined area, a capacitance is generated between the conductor 22a and the surrounding ground conductor, and this capacitance causes the antenna element 22 to be a head capacitor. Configure a city-type antenna. Thereby, the length of the conductor 22b for resonating at the first frequency f1 can be shortened. Therefore, since the shape of the antenna element 20A can be reduced in size, the mounting area on the parent circuit board can be reduced, and the electronic device can be reduced in size.
[0063]
  Next, a sixth embodiment of the present invention will be described.
[0064]
  FIG. 9 is an exploded perspective view showing an antenna element according to the sixth embodiment. In the figure, the same components as those of the fifth embodiment described above are denoted by the same reference numerals, and the description thereof is omitted. Further, the difference between the antenna element 20B of the sixth embodiment and the antenna element 20A of the fifth embodiment is that conductors 24a to 24c equivalent to these are provided instead of the conductors 22a to 22c, and thereby the antenna That is, the element 24 is configured.
[0065]
  The conductor 24a is equivalent to the conductor 22a described above, and the conductor 24b corresponding to the conductor 22b and the conductor 24c corresponding to the conductor 22c are formed in a meandering shape. Thus, by making the conductors 24b and 24c meander, the antenna element 24 can resonate with the first frequency within a small area. Therefore, since the shape of the antenna element 20B can be reduced in size, the mounting area on the parent circuit board can be reduced.
[0066]
  Next, a seventh embodiment of the present invention will be described.
[0067]
  FIG. 10 is an external perspective view showing an antenna element according to the seventh embodiment, and FIG. 11 is an exploded perspective view thereof. In the figure, reference numeral 30A denotes an antenna element, which is provided with a conductor 32 for forming an antenna element and a passive electrode 33 on the upper surface of an insulating substrate 31 made of a dielectric ceramic material. , 33 so that the same substrate 31 is laminated and integrated so as to sandwich it. Furthermore, an external terminal 34A and a grounding external terminal 34B constituting a power feeding unit are formed on each of two adjacent side surfaces of the two stacked substrates 31.
[0068]
  Although not shown, a plurality of dummy electrodes are formed on the back surface of the lower substrate 31 so as to be stably soldered and fixed when mounted on the parent circuit substrate.
[0069]
  The conductor 32 constituting the antenna element has a substantially square shape having a predetermined area for radiating electromagnetic waves, and the central portion of one side thereof is connected to the external terminal 34A serving as a feeding point.
[0070]
  The conductor 33 has a band shape with a predetermined width and is provided to extend in a direction perpendicular to the other side of the conductor 32. One end of the conductor 33 is arranged at a predetermined distance from the conductor 32, and the other end is It is connected to an external terminal 34B for grounding. The distance between the conductor 33 and the conductor 32 and the length of the conductor 33 are set so that the antenna element 32 resonates with the first frequency f1 within the first frequency band to be used.
[0071]
  According to the antenna element 30A having the above-described configuration, the conductor 32 having a predetermined area forming the antenna element.WhenBy electrical coupling with the conductor 33, it can resonate with the first frequency f1. Therefore, since the shape of the antenna element 30A can be reduced in size, the mounting area on the parent circuit board can be reduced, and the electronic device can be reduced in size.
[0072]
  Next, an eighth embodiment of the present invention will be described.
[0073]
  FIG. 12 is an exploded perspective view showing an antenna element according to the eighth embodiment. In the figure, the same components as those in the seventh embodiment are denoted by the same reference numerals, and the description thereof is omitted. The difference between the antenna element 30B of the eighth embodiment and the antenna element 30A of the seventh embodiment is that the conductor 33 is formed in a meandering shape. Thus, by making the conductor 33 meander, the antenna element 32 can resonate with the first frequency f1 within a small area. Therefore, since the shape of the antenna element 30B can be reduced in size, the mounting area on the parent circuit board can be reduced.
[0074]
  Next, a ninth embodiment of the present invention will be described.
[0075]
  FIG. 13 is an external perspective view showing an antenna element according to the ninth embodiment, and FIG. 14 is an exploded perspective view thereof. In the figure, reference numeral 40A denotes an antenna element, which is an element body 41 formed by laminating four insulator layers 41a to 41d made of a dielectric ceramic, and conductors 42 to 40 constituting an antenna element provided inside the element body 41. 44 and an external terminal 46 formed on one side surface of the element body 41.
[0076]
  Although not shown, a plurality of dummy electrodes are formed on the back surface of the lowermost insulator layer 41d so as to be stably soldered when mounted on the parent circuit board.
[0077]
  A substantially square conductor 42 having a predetermined area is provided on the upper surface of the second insulator layer 41b from the top, and a protruding portion 42a is formed at substantially the center of one side thereof, and a via hole 45A is formed in the protruding portion 42a. Is formed.
[0078]
  A strip-shaped conductor 43 having a predetermined width is provided on the upper surface of the third insulator layer 41c, and one end in the length direction thereof is disposed at a position connected to the via hole 45A. Further, the other portion of the conductor 43 excluding the other end in the length direction is disposed so as to face the conductor 42 with the insulator layer 41b interposed therebetween. That is, the length of the conductor 42 in the length direction of the conductor 43 is set to be shorter than the length of the conductor 43. A via hole 45B is formed at the other end of the conductor 43 in the length direction.
[0079]
  A strip-shaped conductor 44 having a predetermined width is provided on the upper surface of the lowermost insulator layer 41d, and one end in the length direction thereof is disposed at a position connected to the via hole 45B. Further, the other portion of the conductor 44 except the other end portion is disposed so as to face the conductor 43 with the insulator layer 41c interposed therebetween, and the other end in the length direction is connected to the external terminal 46 serving as a feeding point. Has been.
[0080]
  The conductors 42 to 44 are connected in series via via holes 45A and 45B to form an antenna element, and the total length is set to a length that resonates with the first frequency f1 in the first frequency band to be used. ing.
[0081]
  According to the antenna element having the above configuration, the conductors 42 to 44 divided in the length direction of the antenna element are arranged in different layers, so that the area when the element is mounted on the parent circuit board is reduced. Further, the lengths of the conductors 42 to 44 of the respective layers facing each other by folding the antenna element are shortened as approaching the front end of the antenna element, and the front end of the antenna element or the folded via hole connecting portion is adjacent to the rear end side. Since it is configured so as to be located on the folded side with respect to the folded portion or the feeding point of the antenna element, the usable frequency bandwidth is expanded.
[0082]
  Further, since the conductor 42 at the tip portion of the antenna element is formed wider than the width of the conductors 43 and 44 in other parts, a capacitance is generated between the conductor 42 and the surrounding ground conductor. The antenna element constitutes a head capacity type antenna by the electrostatic capacity. Thereby, the length of the antenna element resonating at the first frequency f1 can be shortened.
[0083]
  In addition, since the antenna element is folded, the conductors facing each other are electrically coupled to each other and resonate with the second frequency f2 in the second frequency band different from the first frequency band, and the second frequency band. It can also be used.
[0084]
  Further, by adjusting the distance between the conductors 42 to 44 in each layer, that is, the thickness of the insulator layers 41b and 41c, etc., the electrical coupling state between these conductors 42 to 44 is changed to change the first frequency. The interval between the band and the second frequency band can be changed.
[0085]
  Moreover, since the conductors 42 to 44 constituting the antenna element are stacked via the insulator layer, the area when the element is mounted on the parent circuit board can be reduced.
[0086]
  Next, a tenth embodiment of the present invention will be described.
[0087]
  FIG. 15 is an exploded perspective view showing an antenna element according to the tenth embodiment. In the figure, the same components as those in the ninth embodiment are denoted by the same reference numerals, and the description thereof is omitted. The difference between the antenna element 40B of the tenth embodiment and the antenna element 40A of the ninth embodiment is that conductors 47 and 48 equivalent to these are provided instead of the conductors 43 and 44. .
[0088]
  Each of the conductor 47 corresponding to the conductor 43 and the conductor 48 corresponding to the conductor 44 has a meandering shape, and is formed so as to overlap with each other through the insulator layer 41c.
[0089]
  In other words, a strip-shaped and meandering conductor 47 having a predetermined width is provided on the upper surface of the third insulator layer 41c, and a rectangular land 47a is formed at one end in the length direction to form a via hole 45A. It is arranged at the position connected to. Further, the other portion of the conductor 47 except for the other end in the length direction is disposed so as to face the conductor 42 with the insulator layer 41b interposed therebetween. A rectangular land 47b is formed at the other end of the conductor 47 in the length direction, and a via hole 45B is formed in the land 47b. A strip-shaped and meandering conductor 48 having a predetermined width is provided on the upper surface of the lowermost insulator layer 41d, and a rectangular land 48a is formed at one end in the length direction. The land 48a is a via hole. It is arranged at a position connected to 45B. Further, the other portion of the conductor 48 except the other end portion is disposed so as to face the conductor 47 with the insulator layer 41c interposed therebetween, and the other end in the length direction is connected to the external terminal 46 serving as a feeding point. Has been.
[0090]
  Thus, by making the conductors 47 and 48 meander, the antenna element can resonate with the first frequency within a small area. Therefore, since the shape of the antenna element 40B can be reduced in size, the mounting area on the parent circuit board can be reduced.
[0091]
  Next, an eleventh embodiment of the present invention will be described.
[0092]
  FIG. 16 is an exploded perspective view showing an antenna element according to the eleventh embodiment. In the figure, reference numeral 50A denotes an antenna element, which is an element body formed by laminating four insulator layers 51a to 51d made of a dielectric ceramic, and conductors 52 to 54 constituting an antenna element provided inside the element body. The two external terminals 56A and 56B formed on the side surface of the element body.
[0093]
  Although not shown, a plurality of dummy electrodes are formed on the back surface of the lowermost insulator layer 51d so as to be stably fixed by soldering when mounted on the parent circuit board.
[0094]
  A substantially square conductor 52a having a predetermined area and a strip-like conductor 52b projecting in a substantially right angle direction from the substantially center of one side of the conductor 52a are formed on the upper surface of the second insulator layer 51b from the top. In addition, a via hole 55A is formed at the tip of the strip-shaped conductor 52b.
[0095]
  A strip-shaped conductor 53 having a predetermined width is provided on the upper surface of the third insulator layer 51c, and one end in the length direction thereof is disposed at a position connected to the via hole 55A. The insulating layer 51b is disposed so as to face the conductor 52b. The other end of the conductor 53 in the length direction is located at a connection portion between the conductor 52a and the conductor 52b, and a via hole 55B is formed at the other end.
[0096]
  T-shaped conductors 54a and 54b having a predetermined width are provided on the upper surface of the lowermost insulator layer 51d, and these conductors 54a and 54b are connected in a T-shape.
[0097]
  One end of the conductor 54a in the length direction is disposed at a position connected to the via hole 55B. Further, the other portion of the conductor 54a except the other end portion is disposed so as to face the conductor 53 with the insulator layer 51c interposed therebetween, and the other end in the length direction is connected to the grounding external terminal 56B. ing.
[0098]
  Further, one end of the conductor 54b is connected to a predetermined position in the central portion in the length direction of the conductor 54a so as to intersect at right angles, and the other end of the conductor 54b is connected to an external terminal 56A serving as a feeding point.
[0099]
  The conductors 52 to 54 are connected in series via via holes 55A and 55B to form an antenna element generally called an inverted F type, and the total length thereof is the first frequency f1 in the first frequency band to be used. It is set to the length that resonates with.
[0100]
  According to the antenna element having the above configuration, the conductors 52 to 54 divided in the length direction of the antenna element are arranged in different layers, so that the area when the element is mounted on the parent circuit board is reduced.
[0101]
  Further, since the conductor 52a at the tip portion of the antenna element is formed wider than the conductors 52b, 53, 54a, 54b in the other parts, there is a capacitance between the conductor 52 and the surrounding ground conductor. Due to this capacitance, the antenna element constitutes a head capacity type antenna. Thereby, the length of the antenna element resonating at the first frequency f1 can be shortened.
[0102]
  In addition, since the antenna element is folded, the conductors facing each other are electrically coupled to each other and resonate with the second frequency f2 in the second frequency band different from the first frequency band, and the second frequency band. It can also be used.
[0103]
  Further, by adjusting the distance between the conductors 52 to 54 in each layer, that is, the thickness of the insulator layers 51b and 51c, etc., the electrical coupling state between these conductors 52 to 54 is changed to change the first frequency. The interval between the band and the second frequency band can be changed.
[0104]
  Further, since the conductors 52 to 54 constituting the antenna element are laminated via the insulator layer, the area when the element is mounted on the parent circuit board can be reduced.
[0105]
  Next, a twelfth embodiment of the present invention will be described.
[0106]
  FIG. 17 is an exploded perspective view showing an antenna element according to the twelfth embodiment, and FIG. 18 is a plan view thereof. In the figure, reference numeral 60A denotes an antenna element, which is an element body formed by laminating three insulator layers 61a to 61c made of a dielectric ceramic, a conductor 62 constituting an antenna element provided inside the element body, and a resonance element. The conductor 63 and two external terminals 64A and 64B formed on the side surface of the element body.
[0107]
  Further, although not shown, a plurality of dummy electrodes are formed on the back surface of the lowermost insulator layer 61c so as to be stably soldered when mounted on the parent circuit board.
[0108]
  A substantially square conductor 62 having a predetermined area suitable for electromagnetic wave radiation is provided on the upper surface of the second insulator layer 61b from the top, and the center of one side of the conductor 62 is an external terminal for feeding. 64A. The conductor 62 constitutes an antenna element.
[0109]
  A strip-shaped conductor 63 having a predetermined width is provided on the upper surface of the lowermost insulator layer 61c. The conductor 63 is provided so as to extend in a direction perpendicular to the other side of the conductor 62, one end of which is arranged at a predetermined distance from the conductor 62, and the other end is connected to the grounding external terminal 64B. It is connected. Further, the distance between the conductor 63 and the conductor 62 and the length of the conductor 63 are set so that the conductor 62 as an antenna element resonates at the first frequency f1 in the first frequency band to be used. ing.
[0110]
  According to the antenna element 60A having the above-described configuration, the conductor 62 having a predetermined area forming the antenna element.WhenBy electrical coupling with the conductor 63, the first frequency f1 can be resonated. Therefore, since the shape of the antenna element 60A can be reduced in size, the mounting area on the parent circuit board can be reduced, and the electronic device can be reduced in size.
[0111]
  Furthermore, since each of the conductor 62 and the conductor 63 is arranged in a different layer, the arrangement and interval can be easily changed when the electrical coupling state between them is changed.
[0112]
  Next, a thirteenth embodiment of the present invention is described.
[0113]
  FIG. 19 is an exploded perspective view showing an antenna element according to the thirteenth embodiment. In the figure, the same components as those of the twelfth embodiment described above are denoted by the same reference numerals, and description thereof is omitted. Further, the difference between the antenna element 60B of the thirteenth embodiment and the twelfth embodiment is that an insulating layer 61d is newly added and laminated on the second layer from the upper side.
[0114]
  The second insulator layer 61d is made of a dielectric ceramic like the other insulator layers 61a to 61c, and the upper surface thereof has a predetermined width so as to overlap the conductor 63 via the insulator layers 61d and 61b. A strip-shaped conductor 65 is provided. The conductor 65 is provided so as to extend in a direction perpendicular to one side of the conductor 62, one end of which is arranged at a predetermined distance from the conductor 62, and the other end is connected to the grounding external terminal 64B. ing.
[0115]
  The conductor 63 and the distance between the conductor 65 and the conductor 62 and the length of each of the conductors 63 and 65 are the first in the first frequency band in which the conductor 62 as the antenna element is to be used. It is set to resonate at the frequency f1.
[0116]
  According to the antenna element 60B configured as described above, the conductor 62 having a predetermined area forming the antenna element can be resonated with the first frequency f1 by electrical coupling with the conductors 63 and 65. Therefore, since the shape of the antenna element 60A can be reduced in size, the mounting area on the parent circuit board can be reduced, and the electronic device can be reduced in size.
[0117]
  Further, since each of the conductor 62 and the conductors 63 and 65 is arranged in a different layer, the fine adjustment of the arrangement and the interval is performed when changing the electrical coupling state between them. This can be performed more easily than in the embodiment.
[0118]
  Next, the present inventionReference exampleWill be explained.
[0119]
  FIG.Reference exampleFIG. 21 is an exploded perspective view showing an antenna element in FIG. In the figure, reference numeral 70 denotes an antenna element, which is a rectangular parallelepiped element 71 formed by laminating nine insulator layers 74a to 74i having a rectangular surface made of dielectric ceramic, and an antenna provided inside the element 71. A plurality of conductors 75, 77, 78 constituting the element 72, a plurality of via-hole conductors 76 connecting these conductors 75, 77, 78 in series, and an external terminal 73 for power feeding formed on the side surface of the element body 71 It consists of and.
[0120]
  Each insulator layer element body 74a to 74i is laminated so as to be orthogonal to the bottom surface 71a of the element body 71 that contacts the surface of the parent circuit board when the antenna element 70 is mounted on the parent circuit board.
[0121]
  Although not shown, a plurality of dummy electrodes are formed on the bottom surface 71a of the element body 71 so as to be stably fixed by soldering when mounted on the parent circuit board.
[0122]
  The first and ninth insulator layers 74a and 74i are dummy, and the surface of the second insulator layer 74b includes four L-shaped strips 75a and 75b perpendicular to each other. The conductors 75 are provided in a state where they are translated from each other with a predetermined interval. Each of these conductors 75 has one strip 75a parallel to the bottom surface 71a, the other strip 75b perpendicular to the bottom 71a, and the other strip 75b positioned on the bottom 71a side. Has been placed. Further, the tip of the strip 75 a of one conductor 75 disposed in the vicinity of the side surface of the element body 71 is connected to the external terminal 73.
[0123]
  A plurality of via holes are formed in each of the third to seventh insulator layers 74c to 74g, and these via holes are filled with via hole conductors 76. The arrangement of these via-hole conductors is set to be the same position in each of the insulator layers 74c to 74g, and the via-hole conductors 76 at the same position are connected to each other when stacked.
[0124]
  On the surface of the insulator layer 74h of the eighth layer, three L-shaped conductors 77 made of two strips 77a and 77b orthogonal to each other are provided in a state where they are translated from each other at a predetermined interval. And a conductor 78 corresponding to the tip of the antenna element 72 is provided. In each of these conductors 77, one strip 77a is parallel to the bottom surface 71a, the other strip 77b is perpendicular to the bottom 71a, and the other strip 77b is positioned on the bottom 71a side. Has been placed.
[0125]
  By laminating each of the insulator layers 74a to 74i, the conductors 75, 77, and 78 are connected in series via the via-hole conductor 76 to constitute the antenna element 72. The length of the antenna element 72 is set to a length that resonates with the first frequency f1 in the first frequency band to be used.
[0126]
  According to the antenna element 70 having the above configuration, a plurality of conductors 75, 77, and 78 are connected in series via the via-hole conductors 76 to constitute a helical antenna embedded in the element body 71. It can be formed small. Further, since the strips 75a and 77a extending in parallel with the bottom surface 71a of the conductors 75 and 77 are disposed away from the bottom surface 71a, the portion disposed in the vicinity of the bottom surface of the antenna element 72 is the minimum necessary. become. For this reason, when mounted on the parent circuit board, the influence of other conductors and ground conductors existing on the parent circuit board can be reduced.
[0127]
  Each embodiment mentioned above is an example of the present invention, and the present invention is not limited only to these.
[0128]
  When an antenna element is mounted on a portable telephone, as shown in FIG. 22, electromagnetic waves radiated from the antenna element to the human body at a talk position where the telephone 81 is placed at the ear of the user's human head 82. It is preferable to arrange and mount so that the directivity of is minimal.
[0129]
【The invention's effect】
  As described above, according to the antenna element of the first to third aspects of the present invention, the usable frequency bandwidth is expanded by devising the folding position of the antenna element, and used in a wide frequency band. It becomes a possible antenna.
[0130]
  Moreover, according to the antenna element of Claim 4 thru | or 6, while the antenna element comprises the antenna generally called reverse F type, the width | variety of the conductor of the front-end | tip part of an antenna element is other than that. Because it is formed wider than the width of the part, a capacitance is generated between the conductor at the tip and the surrounding ground conductor, and this capacitance forms the head capacity type antenna. Therefore, the length of the antenna element that resonates with the first frequency can be shortened.
[0131]
  Also,Claims 7 and 8According to the antenna element described in (1), the usable frequency bandwidth is expanded by devising the folding position of the antenna element, and the antenna can be used in a wide frequency band. In addition, the conductor and grounding conductor that form the antenna element are stacked via an insulator layer, so that the mounting area when mounted on the parent circuit board can be reduced compared to conventional devices, and the size of the device can be reduced. The resonance frequency and the frequency band can be easily adjusted.
[0132]
  According to the antenna element of claims 9 to 12, when the capacitance between the first conductor and the second conductor serving as the antenna element increases, the frequency bandwidth including the resonance frequency is widened. In addition, since the resonance frequency tends to decrease, the resonance frequency and the frequency bandwidth can be easily set to desired values by changing the electrostatic capacitance in the capacitive coupling between the first conductor and the second conductor.
[Brief description of the drawings]
FIG. 1 is an external perspective view showing an antenna element according to a first embodiment of the present invention.
FIG. 2 is an exploded perspective view showing an antenna element according to the first embodiment of the present invention.
FIG. 3 is a diagram showing a characteristic curve of an antenna element according to the first embodiment of the present invention.
FIG. 4 is a plan view showing an antenna element according to a second embodiment of the present invention.
FIG. 5 is a plan view showing an antenna element according to a third embodiment of the present invention.
FIG. 6 is a plan view showing an antenna element according to a fourth embodiment of the present invention.
FIG. 7 is an external perspective view showing an antenna element according to a fifth embodiment of the present invention.
FIG. 8 is an exploded perspective view showing an antenna element according to a fifth embodiment of the present invention.
FIG. 9 is an exploded perspective view showing an antenna element according to a sixth embodiment of the present invention.
FIG. 10 is an external perspective view showing an antenna element according to a seventh embodiment of the present invention.
FIG. 11 is an exploded perspective view showing an antenna element according to a seventh embodiment of the present invention.
FIG. 12 is an exploded perspective view showing an antenna element according to an eighth embodiment of the present invention.
FIG. 13 is an external perspective view showing an antenna element according to a ninth embodiment of the present invention.
FIG. 14 is an exploded perspective view showing an antenna element according to a ninth embodiment of the present invention.
FIG. 15 is an exploded perspective view showing an antenna element according to a tenth embodiment of the present invention.
FIG. 16 is an exploded perspective view showing an antenna element according to an eleventh embodiment of the present invention.
FIG. 17 is an exploded perspective view showing an antenna element according to a twelfth embodiment of the present invention.
FIG. 18 is a plan view showing an antenna element according to a twelfth embodiment of the present invention.
FIG. 19 is an exploded perspective view showing an antenna element according to a thirteenth embodiment of the present invention.
FIG. 20 shows the present invention.Reference exampleExternal perspective view showing antenna element in
FIG. 21 shows the present invention.Reference exampleThe exploded perspective view which shows the antenna element in
FIG. 22 is a diagram for explaining a method of mounting an antenna element according to the present invention.
[Explanation of symbols]
  10A, 10b, 10C, 10D ... antenna element, 11 ... substrate, 12 ... antenna element, 12a to 12i ... conductor, 13 ... external terminal, 20A, 20B ... antenna element, 21 ... substrate, 22 ... antenna element, 22, 22a, 22b, 22c ... conductor, 23A, 23B ... external terminal, 24, 24a, 24b, 24c ... conductor, 30A, 30B ... antenna element, 31 ... substrate, 32, 33 ... conductor, 34A, 34B ... external Terminal, 40A, 40B ... Antenna element, 41 ... Element, 41a-41d ... Insulator layer, 42-44 ... Conductor, 45A, 45B ... Via hole, 46 ... External terminal, 47, 48 ... Conductor, 50A ... Antenna Element, 51a to 51d ... Insulator layer, 52 to 54 ... Conductor, 55A, 55B ... Via hole, 56A, 56B ... External terminal, 60A, 6 B ... Antenna element, 61a to 61d ... Insulator layer, 62, 63 ... Conductor, 64A, 64B ... External terminal, 65 ... Conductor, 70 ... Antenna element, 71 ... Element, 71a ... Bottom, 72 ... Antenna element 73 ... external terminals, 74a to 74i ... insulator layer, 75 ... conductor, 76 ... via-hole conductor, 77,78 ... conductor, 81 ... portable telephone, 82 ... human body head.

Claims (12)

A strip-shaped conductor which is provided on the surface of the plate-like insulator and forms an antenna element which is alternately folded and meandered;
An external terminal connected to the rear end of the antenna element;
The front end or folded portion of the antenna element is located on the folded side from the adjacent folded portion on the rear end side or the rear end of the antenna element, and
The length of the antenna element is set to a length that resonates at least with a predetermined first frequency within the first frequency band,
The antenna element according to claim 1, wherein a conductor at a tip portion of the antenna element is formed wider than a conductor at another portion.   The antenna element according to claim 1, wherein the adjacent folded conductors are arranged so as to be parallel to each other.   2. The antenna element according to claim 1, wherein another flat insulator is laminated on the surface of the flat insulator so as to sandwich the conductor. An element body formed by laminating a plurality of insulator layers provided with conductors on the surface, an external terminal constituting a power feeding portion provided on the outer surface of the element body, and provided on the outer surface of the element body With external terminals for grounding ,
The conductor of the predetermined layer forms an antenna element, and the antenna element is
A tip conductor located at the tip of the antenna element and having a wider width than the other parts;
A strip-shaped conductor connecting the tip conductor and the grounding external terminal;
One end is connected to a predetermined position of the strip-shaped conductor, and the other end is configured from a strip-shaped branch conductor connected to an external terminal constituting the power feeding unit,
The connection point between the branch conductor and the strip conductor is set at a position where an impedance at an external terminal constituting the power feeding unit matches a predetermined power feeding point impedance . An element body formed by laminating a plurality of insulator layers each provided with a conductor on the surface, an external terminal constituting a power feeding portion provided on the outer surface of the element body, and an outer surface of the element body. And an external terminal for grounding
  The conductor of the predetermined layer forms an antenna element, and the antenna element is
  A tip conductor located at the tip of the antenna element and having a wider width than the other parts;
  A strip-shaped conductor connecting the tip conductor and the grounding external terminal;
  One end is connected to a predetermined position of the strip-shaped conductor, and the other end is configured from a strip-shaped branch conductor connected to an external terminal constituting the power feeding unit,
  The length of the antenna element is set to a length that resonates with a predetermined first frequency within the first frequency band, and
  The connection point between the branching conductor and the belt-like conductor is set at a position where the impedance at the external terminal constituting the feeding part matches a predetermined feeding point impedance.
  An antenna element characterized by that. The strip-shaped conductors are connected in series via via holes so as to be alternately folded into a plurality of different layers.
The antenna element according to claim 5. It consists of an element body formed by laminating a plurality of insulator layers provided with conductors on the surface, and an external terminal provided on the outer surface of the element body,
The first conductor of the predetermined layer forming the antenna element has a band shape, and the antenna element is formed by being connected in series via via holes so that the first conductors of different layers are alternately folded,
The rear end of the antenna element is connected to the external terminal and the front end is an open end;
The front end of the first conductor in each layer forming the antenna element is located closer to the front end of the conductor than the rear end of the conductor connected to the rear end of the conductor;
The length of the antenna element is set to a length that resonates at least with a predetermined first frequency within the first frequency band ,
Features and to luer antenna element that conductors of the tip portion of the antenna element has a width wider than the other portions. The first conductor is disposed at a position where electrical coupling is generated between the first conductors of different layers, and the arrangement is such that the antenna element adds the first frequency in addition to the first frequency. The antenna element according to claim 7 , wherein the antenna element is set so as to resonate also with a predetermined second frequency within a second frequency band different from the band. An element body formed by laminating a plurality of insulator layers having conductors provided on the surface, a first external terminal constituting a power feeding portion provided on the outer surface of the element body, and an outer surface of the element body A second external terminal for grounding provided,
A first conductor forming the antenna element having a predetermined area and connected to the first external terminal provided on a predetermined layer, the second conductive band-shaped end portion is capacitively coupled to said first conductor With a body,
The other end of the second conductor is connected to the second external terminal ;
The length of the second conductor, the first conductor characteristics and to luer antenna element that is set to a length which resonates at a predetermined first frequency in the first frequency band. The second conductor is provided in the same layer as the layer in which the first conductor is disposed.
The antenna element according to claim 9. The second conductor is provided in a layer different from the layer in which the first conductor is disposed.
The antenna element according to claim 9. The antenna element according to claim 11 , wherein the second conductor is provided on each of two layers sandwiching the layer on which the first conductor is provided.

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