JP2006222918A - Meander line antenna and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a meander line antenna which can be downsized and has high radiation efficiency. <P>SOLUTION: The meander line antenna 40 places an antenna element 41 of an extended conductor inflected into reverse direction in repetitious fashion and placed in planar state, a feeding point 12 placed in the central area of the antenna element 41, and dielectrics 42 and 43 near the antenna element 41 in the manner that sandwich both sides of the antenna element 41. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention has a function of radiating a radio wave from a conductor portion to a space by applying a high-frequency voltage to a power feeding portion used in, for example, a small wireless tag for ubiquitous communication, a small wireless sensor for bioembedding, a cellular phone, etc. The present invention relates to a very small meander line antenna having a physical dimension of 1/10 or less of the wavelength, and in particular, a method for manufacturing a meander line antenna that can be miniaturized and has high radiation efficiency, and a meander line Regarding antennas.

In ubiquitous communication, an attempt has been made to affix a tag (RFID) that is identified by radio waves to a product that is handled at a sales site, for use in the distribution of the product. For the RFID, a meander line antenna using a meander-shaped element is used. The meander line antenna is used for mobile phones and the like in addition to RFID. For example, Patent Document 1 discloses antenna means for a portable wireless communication device using a meander-shaped radiating element.
Special Table 2000-516056

  By the way, a meander line antenna used for applications such as RFID has a restriction that its external dimensions must be kept to a predetermined size when used in a small electronic device such as an RFID or a mobile phone. For this reason, the meander line antenna used in such an electronic device is required to have the radiation efficiency required for the electronic device while satisfying the above-mentioned size restriction.

  The present invention has been made in view of such a background, and an object of the present invention is to provide a meander line antenna manufacturing method and a meander line antenna that can be reduced in size and have high radiation efficiency.

  The invention described in claim 1 of the present invention for solving the above-mentioned problems is a meander in which continuous conductors are repeatedly bent in the opposite direction and arranged in a plane, and a feeding point is provided at the center of the conductor. In the method for manufacturing a line antenna, a dielectric is disposed close to the conductor, and the dielectric constant of the dielectric is changed to change the number of bent portions of the conductor.

  The invention according to claim 2 is the method of manufacturing the meander line antenna according to claim 1, wherein the dielectric is disposed close to the conductor so as to be sandwiched from both sides of the conductor. And

  The invention described in claim 3 is the method of manufacturing the meander line antenna according to claim 1 or 2, wherein the conductor has a line width where the flowing current amount is large and a portion where the flowing current amount is small. It is assumed that the line width is larger than the line width.

  According to a fourth aspect of the present invention, there is provided the meander line antenna manufacturing method according to the third aspect, wherein the line width of the conductor is made narrower as the distance from the feeding point increases.

  The invention according to claim 5 is a method for manufacturing a meander line antenna, and is continuous with a first element formed by repeatedly bending a continuous first conductor in a reverse direction and arranging it in a planar shape. The second element formed by repeatedly bending the second conductor in the opposite direction and arranged in a plane is arranged in the same plane, and a feeding point is provided at the center of the first element, and the first and first elements By short-circuiting the ends of the two conductors, a loop connecting the first and second conductors is formed, and a dielectric is disposed close to the loop so as to be sandwiched from both sides of the loop. I will do it.

  Further, the invention according to claim 6 is a method for manufacturing a meander line antenna, wherein a first element formed by repeatedly bending a continuous first conductor in a reverse direction and arranging it in a plane is arranged. A second element formed by repeatedly bending a continuous second conductor in the opposite direction and arranging in a plane is disposed, and a feeding point is provided at the center of the first element, and the first and second elements By short-circuiting the ends of the conductors, a loop connecting the first and second conductors is formed, and a dielectric is disposed on the plane on which the first conductor is disposed, and the second conductor is disposed on the dielectric. The first and second conductors are arranged close to each other so as to be sandwiched between the two planes.

  The invention according to claim 7 is the method of manufacturing the meander line antenna according to claim 6, wherein the second dielectric is the dielectric on the plane on which the first conductor is disposed. A first dielectric is disposed close to the first conductor from a surface different from the surface adjacent to the first conductor, and a third dielectric is disposed on the second conductor. It is assumed that the first dielectric is arranged close to the second conductor from a plane different from the plane where the first dielectric is close to the second conductor.

  The invention according to claim 8 is the method of manufacturing the meander line antenna according to any one of claims 5 to 7, wherein an amount of current flowing through at least one of the first and second conductors is set. The line width of the large part is formed to be thicker than the line width of the part where the amount of flowing current is small.

  The invention according to claim 9 is the method of manufacturing the meander line antenna according to claim 8, wherein the line width of at least one of the first and second conductors is set apart from the feeding point. It is supposed to be thin.

  The invention according to claim 10 is a meander line antenna, wherein a continuous conductor is repeatedly bent in the opposite direction and arranged in a plane, and a feeding point provided at the center of the element. And a dielectric disposed in proximity to the conductor so as to be sandwiched from both sides of the element.

  The invention according to claim 11 is the meander line antenna according to claim 10, wherein, for the conductor, the line width of the portion where the flowing current amount is large is larger than the line width of the portion where the flowing current amount is small. It will be fat.

  The invention according to claim 12 is the meander line antenna according to claim 11, wherein the line width of the conductor becomes narrower as the distance from the feeding point increases.

  The invention according to claim 13 is a meander line antenna, wherein the first element is formed by repeatedly bending a continuous first conductor in the reverse direction and arranging the first conductor in a planar shape, and the first conductor. A second element that is arranged in the same plane as the plane in which the second element is arranged and is arranged in a plane by repeatedly bending the second continuous conductor in the opposite direction; and provided in the center of the first element The feed point and the loop formed by short-circuiting the ends of the first and second conductors, the loop connecting the first and second conductors, and sandwiching from both sides of the loop, And a dielectric disposed close to the loop.

  The invention according to claim 14 is a meander line antenna, wherein a first element formed by repeatedly bending a continuous first conductor in a reverse direction and arranging in a planar shape, and a continuous second A second element formed by repeatedly bending a conductor in the opposite direction and arranged in a planar shape, a feeding point provided at a central portion of the first element, and ends of the first and second conductors It is sandwiched between a loop formed by short-circuiting and connecting the first and second conductors, a plane on which the first conductor is disposed, and a plane on which the second conductor is disposed. A dielectric close to the first and second conductors.

  The invention according to claim 15 is the meander line antenna according to claim 14, wherein the first dielectric that is the dielectric on the plane on which the first conductor is disposed is the first dielectric. The second dielectric material close to the first conductor from a surface different from the surface adjacent to the first conductor, and the first dielectric material in a plane on which the second conductor is disposed are the second dielectric material. And a third dielectric that is close to the second conductor from a surface that is different from the surface that is close to the conductor.

  The invention according to claim 16 is the meander line antenna according to any one of claims 10 to 15, wherein at least one of the first and second conductors is a portion where a flowing current amount is large. The line width is assumed to be thicker than the line width of the portion where the amount of flowing current is small.

  The invention according to claim 17 is the meander line antenna according to claim 16, wherein the line width of at least one of the first and second conductors is so narrow that the distance from the feeding point increases. To do.

  According to the present invention, it is possible to provide a meander line antenna manufacturing method and a meander line antenna that can be miniaturized and have high radiation efficiency.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows the basic structure of a meander line antenna. A meander line antenna 10 shown in FIG. 1 is an element (hereinafter referred to as an antenna element 11) configured by repeatedly bending continuous conductors in opposite directions and arranging them in a planar shape (hereinafter, this shape is referred to as a meander shape). ). In the meander line antenna 10, the feeding point 12 is provided at the center of the antenna element 11.

With respect to the meander line antenna 10 having the basic structure shown in FIG. 1, the simulation was performed using an electromagnetic field simulator with an antenna length (L) of 0.05λ and an antenna width (W) of 0.04λ. The Smith chart of FIG. 2 shows the calculation result of the input impedance (Zin) when the line width d is 0.1 mm and the total number (N) of bent portions (hereinafter referred to as cranks) in the antenna element 11 is 38. As shown in the figure, it has a resonance point at 708.7 MHz, and the input impedance of the meander line antenna 10 is only a pure resistance component (Rin) at this resonance point. Here, the breakdown of the resistance component Rin is the radiation resistance Rr and the conductor resistance Rl. The radiation efficiency (η) of the antenna is expressed by the following equation.
η = Rr / (Rr + Rl) (1)

Table 1 shows these values.
[Table 1]

  As shown in Table 1, the meander line antenna 10 having the basic structure is characterized in that Rl is 17 times larger than Rr. That is, in the meander line antenna 10 having the basic structure, it means that almost all of the fed radio wave is consumed as heat loss by the conductor resistance Rl. For this reason, the radiation efficiency η of the meander line antenna 10 having the basic structure is a relatively small value of −12.5 dB.

Here, the conductor resistance Rl is expressed by the following equation, where d is the conductor line width and t is the conductor thickness.

式（３）において、ｆは周波数、μは透磁率、σは導電率を表す。 Here, δ is called the skin thickness of the conductor and is expressed by the following equation.

In Expression (3), f represents frequency, μ represents magnetic permeability, and σ represents conductivity.

From Equation (2), the main factors that determine the value of the conductor resistance Rl are the conductor length (La) and the conductor line width (d). In Equation (2), La = 707 mm, d = 0.1 mm and the conductivity of copper used as a conductor σ = 5.8 × 10 ⁷ (S / m) are substituted, and t is omitted from d> t. Rl = 24.5Ω. Rl calculated in this way corresponds well with the value of Rl in Table 1.

  The configuration of the meander line antenna 20 that improves the radiation efficiency of the meander line antenna 10 having the basic structure is shown in FIG. As shown in the figure, the meander line antenna 20 includes an antenna element 11 and an antenna element 21 arranged on the same plane, and a feeding point 12 is provided at the center of the antenna element 11. The ends are short-circuited to form a loop composed of the antenna element 11 and the antenna element 21 (hereinafter, the structure of the meander line antenna 20 is referred to as “folded structure”).

  In the meander line antenna 20 shown in FIG. 3, two antenna elements (11, 21) are used. When the number of antenna elements is M, the main electrical constant (pure resistance) in the meander line antenna of “folded structure” is used. The component Rin ′, the radiation resistance Rr ′, the conductor resistance Rl ′, and the radiation efficiency η ′) are each expressed by the following equations.

Rr ′ = M ² × Rr (4)
Rl '= M × Rl (5)
η ′ = Rr ′ / (Rr ′ + Rl ′) = M ² × Rr / (M ² × Rr + M × Rl) (6)
Here, when Rl ′> Rr ′, Rin ′ is approximately expressed by the following equation.
η′≈Rr ′ / Rl ′ = M × (Rr / Rl) = M × η (7)
In other words, it can be seen that the radiation efficiency can be improved by a factor of M in a “folded structure” meander line antenna using M antenna elements. In the meander line antenna 20 shown in FIG. 3, M = 2, Rr is 4 times, and Rl is 2 times. Table 2 shows the calculation results of the main electric constants of the meander line antenna 20 by the electromagnetic field simulator.

[Table 2]

  Comparing Table 2 and Table 1, the radiation efficiency η is doubled and an increase of 3 dB is observed. Also, from Table 2, it can be seen that Rr and Rl calculated by the electromagnetic field simulator correspond well with the calculated values of Equation (2), and increase rates of about 4 times and about 2 times, respectively.

  Next, a meander line antenna 30 having a configuration different from the “folded structure” as described above is shown in FIG. As shown in the figure, in the meander line antenna 30, the antenna elements 11 and 21 are arranged substantially in parallel, a feeding point 12 is provided at the center of the antenna element 11, and the ends of the antenna elements 11 and 21 are short-circuited. Thus, a loop composed of the antenna element 11 and the antenna element 21 is formed (hereinafter, the structure of the meander line antenna 30 is referred to as “superposition structure”). In the meander line antenna 30, the antenna element 11 and the antenna element 21 are arranged substantially in parallel with a distance (g) of 0.0047λ. Table 3 shows the result of calculation of the main electrical constant of the meander line antenna 30 using an electromagnetic field simulator.

[Table 3]

  Comparing Table 3 and Table 2, it can be seen that the meander line antenna 30 has a radiation efficiency η of −8.3 dB which is close to the radiation efficiency of the meander line antenna 20 described above.

As described above, the introduction of the “folded structure” and the “overlapping structure” can improve the radiation efficiency of the meander line antenna, but M times as much as the number of antenna elements (M) is increased. The increase in efficiency remains. Here, since the electrical constant that greatly affects the radiation efficiency is the conductor resistance (Rl), the radiation efficiency can be improved if the conductor resistance (Rl) can be reduced while maintaining the external dimensions. In order to reduce the conductor resistance (Rl) under the limitation of the external dimensions (antenna length (L) = 0.05λ) in the present embodiment, the conductor length (La) is reduced from the equation (2). Alternatively, it is necessary to increase the conductor line width (d). Here, there is a relationship of the following equation (8) among the maximum line width (d) that the conductor can take, the antenna length (L), and the number of cranks (N).
L ≒ N × d (8)
Since L is determined in advance as a restriction on the outer dimension, it is necessary to reduce N in order to increase d. The possibility that the values of La, N, etc. change for a given L is a change in the medium constant around the antenna. For example, when the dielectric constant is increased, the wavelength of the received radio wave is shortened and the resonance frequency is decreased. Therefore, there is a possibility that the structural specifications in the state where the antenna resonates can be changed by changing the dielectric constant. Thereby, it is considered that the crank number N in the antenna element of the meander line antenna can be changed.

  Therefore, first, the present inventor tried to sandwich the antenna element with a dielectric. A perspective view of the meander line antenna 40 having such a configuration is shown in FIG. FIG. 6 is a plan view of the meander line antenna 40 (note that the dielectric is not shown in FIG. 6). A meander line antenna 40 shown in FIGS. 5 and 6 includes an antenna element 41, a feeding point 12 provided at the center of the antenna element 41, and a dielectric 42 adjacent to the antenna element 41 so as to sandwich the antenna element 41 from both sides. And 43. Here, the dielectrics 42 and 43 may be integrated. The thicknesses h of the dielectrics 42 and 43 are 0.0023λ.

  When the dielectric is “close to” the antenna element, the dielectric and the antenna element are in contact with each other, the dielectric and the antenna element are in close contact with the adhesive, or the dielectric is the antenna element. It also includes a state in which the crank portion is in close contact with the crank portion.

In the meander line antenna 40 shown in FIG. 5, when the relative permittivity ε _r of the dielectrics 42 and 43 is 10, the crank number N = 14. That is, the antenna length (L) of the meander line antenna 40 is not changed from 0.05λ of the meander line antenna 10 shown in FIG. 1, but the crank number N can be greatly reduced from 38 to 14. Accordingly, the conductor line width could be increased from 0.1 mm to 0.6 mm. Here, the calculation result by the electromagnetic field simulator of the input impedance (Zin) of the meander line antenna 40 is shown in the Smith chart of FIG. As shown in the figure, it has a resonance point at 704.8 MHz. Table 4 shows the calculation results of the main electric constants of the meander line antenna 40 by the electromagnetic field simulator.

[Table 4]

  Here, a remarkable point in the comparison between Table 4 and Table 1 is that the value of Rl of 25.4Ω can be reduced to 3.8Ω to 1/6 or less. That is, by bringing the dielectrics (42, 43) close to the antenna element 41 so as to be sandwiched from both surfaces of the antenna element 41, the radiation efficiency η is increased from -12.5 dB to -4.6 dB, 8 dB (slightly 6 times). It will be greatly improved. As described above, in the meander line antenna 40, the dielectric (42, 43) is disposed in the vicinity of the antenna element 41 (conductor), and the dielectric constant of the dielectric (42, 43) is changed, thereby changing the antenna element. The number of cranks 41 (the bent portion) can be changed. Here, if the number of cranks N of the antenna element 41 is reduced, the conductor line width d can be increased correspondingly, thereby reducing the conductor resistance Rl. And by reducing the conductor resistance Rl in this way, the radiation efficiency η of the meander line antenna 40 is improved by the equation (1).

  Next, the conductor line width used for the meander line antenna will be described. In the conductor used in the meander line antenna, the amount of current flowing changes according to the distance from the feeding point. Therefore, it is more effective to have the conductor line width change according to the amount of current flowing through the conductor. Can be small. FIG. 8 is a diagram showing the distribution of the amount of current flowing in the antenna element 41 of the meander line antenna 40 (hereinafter referred to as current distribution). As shown in the figure, in the antenna element 41 of the meander line antenna 40, the current is strongest near the feeding point 12 (45), and the current is zero at both ends (46). Therefore, the conductor resistance of the antenna element 41 can be reduced by forming the conductor line width of the antenna element 41 narrower as the distance from the feeding point 12 of the antenna element 41 increases.

  FIG. 9 is a diagram showing a meander line antenna 50 in which the conductor line width is narrowed away from the feeding point 12, that is, from the center to the end. The meander line antenna 50 shown in FIG. 9 has a conductor line width d1 of the first crank from the end of the antenna element 41 in accordance with the current distribution in the antenna element 41 of the meander line antenna 40 shown in FIG. The conductor line width d2 of the 0.35 mm, the third to fourth cranks is 0.5 mm, and the conductor line width d3 of the fifth to sixth cranks is 0.8 mm. As described above, in the antenna element 51 of the meander line antenna 50, the conductor line width where the flowing current amount is large is thicker than the conductor line width where the flowing current amount is small. Resistance Rl is reduced. And by reducing the conductor resistance Rl in this way, the radiation efficiency η of the meander line antenna 50 is improved by the equation (1).

  Next, in the above-described meander line antenna 20 having the “folded structure” and the meander line antenna 30 having the “overlapping structure”, a configuration in which a dielectric is brought close to the antenna element will be described.

  FIG. 10 is a perspective view of the meander line antenna 60 having a configuration in which the above-described meander line antenna 20 having a “folded structure” is sandwiched between dielectrics. A plan view of the meander line antenna 60 is shown in FIG. 11 (note that the dielectric is not shown in FIG. 11). As shown in FIGS. 10 and 11, the meander line antenna 60 includes an antenna element 41 formed by repeatedly bending a continuous first conductor in the reverse direction and arranging it in a planar shape, and a continuous second conductor. The antenna element 61, which is repeatedly bent in the opposite direction and arranged in a plane, is arranged in the same plane, the feeding point 12 is provided in the center of the antenna element 41, and the ends of the antenna elements 41 and 61 are short-circuited. Thus, a loop connecting the antenna elements 41 and 61 is formed, and the dielectrics 62 and 63 are arranged close to the loop so as to be sandwiched from both surfaces of the loop. In this case, the crank number N of the meander line antenna 60 is 14. Thus, in the meander line antenna 60, the crank number N can be made significantly smaller than the crank number N = 38 of the meander line antenna 10 having the basic structure shown in FIG.

  Table 5 shows values calculated by the electromagnetic simulator for the main electric constants of the meander line antenna 60.

[Table 5]

  Comparing Table 5 and Table 4, Rr has a value of 4 times or more, while Rl has only increased about 2 times. For this reason, the radiation efficiency of the meander line antenna 60 is further improved, and the radiation efficiency η of the meander line antenna 60 has a value of −2.5 dB, which is about 2 dB higher than the meander line antenna 40 shown in FIG. . As described above, in the meander line antenna 60, by arranging the dielectrics 62 and 63 close to the antenna element 61, the crank number N of the antenna element 61 can be reduced, and the conductor line width d can be increased accordingly. Thus, the conductor resistance Rl can be reduced. And by reducing the conductor resistance Rl in this way, the radiation efficiency η of the meander line antenna 60 is improved by the equation (1).

  Next, the meander line antenna 70 in which a dielectric is disposed between the antenna elements 31 and 32 so as to be sandwiched between the antenna elements 31 and 32 of the above-described “stacked structure” meander line antenna 30 will be described. 12 and 13 are perspective views of the meander line antenna 70 (note that the dielectric is not shown in FIG. 13). As shown in FIGS. 12 and 13, in the meander line antenna 70, an antenna element 41 formed by repeatedly bending a continuous first conductor in the opposite direction and arranging in a planar shape is arranged, and a continuous second conductor is arranged. Is repeatedly bent in the opposite direction, the antenna element 61 is arranged in a planar shape, the feeding point 12 is provided in the center of the antenna element 41, and the ends of the antenna elements 41 and 61 are short-circuited, A loop connecting the antenna elements 41 and 61 is formed, and the dielectric element 71 and the antenna element 41 and the dielectric element 71 are sandwiched between the plane on which the antenna element 41 is disposed and the plane on which the antenna element 61 is disposed. It is arranged close to 61.

  Here, the thickness g (distance between the antenna element 41 and the antenna element 61) of the dielectric 71 is 0.0047λ. In this case, the crank number N is 14. Thus, the crank number N of the meander line antenna 70 is significantly smaller than the crank number N = 38 of the meander line antenna 30 shown in FIG. As described above, in the meander line antenna 70, the number N of cranks is reduced, so that the conductor line width d can be increased accordingly, and thereby the conductor resistance Rl can be reduced. And by reducing the conductor resistance Rl in this way, the radiation efficiency η of the meander line antenna 70 is improved by the equation (1). The meander line antenna 70 can be easily created by disposing the antenna element 41 and the antenna element 61 on both surfaces of the flat dielectric 71.

  The meander line antenna 70 may be sandwiched between dielectrics. FIG. 14 is a cross-sectional view of the meander line antenna 80 having this configuration. As shown in the figure, the meander line antenna 80 has a dielectric 81 in proximity to the antenna element 41 from a plane different from the plane on which the antenna element 41 is disposed and the dielectric 71 is close to the antenna element 41. The dielectric 82 is arranged close to the antenna element 61 from a plane different from the plane where the dielectric 71 is close to the antenna element 61 on the plane where the antenna element 61 is arranged. .

In the meander line antenna 70 shown in FIG. 14, the thickness (g) of the dielectric 71 is 2.0 mm, the thickness (k) of the dielectrics 81 and 82 is 1.0 mm, and the relative dielectric of the dielectrics 71, 81 and 82 When the ratio (ε _r ) is 10 and the thicknesses (t) of the antenna elements 41 and 61 are 35 μm, the crank number N is 14. That is, N is significantly smaller than the crank number N = 38 of the meander line antenna 30 shown in FIG. Here, Table 6 shows calculated values of main electric constants of the meander line antenna 80 by the electromagnetic field simulator.

[Table 6]

  When Table 6 and Table 5 are compared, similar values are obtained for both Rr and Rl. A radiation efficiency η of −2.2 dB was obtained. Thus, in the meander line antenna 70, the crank number N of the antenna elements 41 and 61 is reduced, so that the conductor line width d can be increased correspondingly, thereby reducing the conductor resistance Rl. Can do. And by reducing the conductor resistance Rl in this way, the radiation efficiency η of the meander line antenna 70 is improved by the equation (1).

  As described above, according to the meander line antenna of this embodiment, the radiation efficiency of the meander line antenna can be significantly improved without changing the external dimensions of the antenna. Therefore, it is possible to realize a meander line antenna that can be reduced in size and has high radiation efficiency. Thus, for example, when the meander line antenna of this embodiment is used for RFID attached to a package, information on the RFID attached to a more remote package is compared with RFID using a general meander line antenna. Can be read. Further, when the meander line antenna of the present embodiment is used in a wireless communication device such as a mobile phone, it is possible to transmit and receive radio waves with a distant base station, thereby expanding the communicable range.

  Note that, for each of the meander line antenna 60, the meander line antenna 70, and the meander line antenna 80, as in the meander line antenna 50 shown in FIG. The conductor line width may be reduced as the distance from 12 increases. In this case, the conductor resistance can be further reduced, and the radiation efficiency of the meander line antenna can be further improved.

In this embodiment, the relative dielectric constant of the dielectric is ε _r = 10. However, the dielectric is not limited to this, and a dielectric having an arbitrary relative dielectric constant can be used. Also, the thicknesses h, g, and k of the dielectric can be set to arbitrary sizes.

  Although the present embodiment has been described above, the above embodiment is intended to facilitate understanding of the present invention and is not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes equivalents thereof.

It is a figure which shows the basic structure of a meander line antenna. 3 is a diagram illustrating input impedance characteristics of the meander line antenna 10. FIG. It is a figure which shows the meander line antenna 20 of "folding structure". 2 is a diagram showing a meander line antenna 30 having a “superposition structure”. FIG. FIG. 3 is a perspective view of a meander line antenna 40 having a configuration in which an antenna element is sandwiched between dielectric materials. 3 is a plan view of a meander line antenna 40. FIG. FIG. 4 is a diagram showing input impedance characteristics of the meander line antenna 40. 4 is a diagram showing a current distribution in an antenna element 41 of the meander line antenna 40. FIG. It is a figure which shows the meander line antenna 50 of a non-uniform conductor line | wire width. FIG. 6 is a perspective view of a meander line antenna 60 having a configuration in which a “folded structure” meander line antenna 20 is sandwiched between dielectrics. 2 is a plan view of a meander line antenna 60. FIG. FIG. 6 is a perspective view of a meander line antenna 70 having a configuration in which a dielectric is disposed between antenna elements in a “superposition structure”. 3 is a plan view of a meander line antenna 70. FIG. It is sectional drawing of the meander line antenna 80 of the structure which inserted | pinched the meander line antenna 70 with the dielectric material.

Explanation of symbols

10 meander line antenna 11 antenna element 12 feeding point 20 meander line antenna 21 antenna element 30 meander line antenna 40 meander line antenna 41 antenna element 42 dielectric 43 dielectric 50 meander line antenna 51 antenna element 60 meander line antenna 61 antenna element 62 dielectric Body 63 dielectric 70 meander line antenna 71 dielectric 80 meander line antenna 81 dielectric 82 dielectric

Claims (17)

A method of manufacturing a meander line antenna, wherein a continuous conductor is repeatedly bent in the opposite direction and arranged in a plane, and a feeding point is provided at the center of the conductor,
Placing a dielectric close to the conductor;
Changing the dielectric constant of the dielectric to change the number of bent portions of the conductor;
A method of manufacturing a meander line antenna. A method of manufacturing a meander line antenna according to claim 1,
Disposing the dielectric close to the conductor so as to be sandwiched from both sides of the conductor;
A method of manufacturing a meander line antenna. A method of manufacturing a meander line antenna according to claim 1 or 2,
For the conductor, forming the line width of the portion where the amount of flowing current is larger than the line width of the portion where the amount of flowing current is small,
A method of manufacturing a meander line antenna. A method of manufacturing a meander line antenna according to claim 3,
Forming the line width of the conductor so that it is away from the feeding point;
A method of manufacturing a meander line antenna. A first element in which a continuous first conductor is repeatedly bent in the opposite direction and arranged in a plane, and a second element in which a continuous second conductor is repeatedly bent in the opposite direction and arranged in a plane. Are arranged in the same plane,
Providing a feeding point at the center of the first element;
By short-circuiting the ends of the first and second conductors, a loop connecting the first and second conductors is formed,
Disposing a dielectric close to the loop so as to be sandwiched from both sides of the loop;
A method of manufacturing a meander line antenna. A first element formed by repeatedly bending a continuous first conductor in the opposite direction and arranging the first element in a planar shape;
Arranging a second element formed by repeatedly bending a continuous second conductor in the opposite direction and arranging it in a plane;
Providing a feeding point at the center of the first element;
By short-circuiting the ends of the first and second conductors, a loop connecting the first and second conductors is formed,
A dielectric is disposed adjacent to the first and second conductors so as to be sandwiched between a plane on which the first conductor is disposed and a plane on which the second conductor is disposed. thing,
A method of manufacturing a meander line antenna. A method of manufacturing a meander line antenna according to claim 6,
The second dielectric is formed from a plane different from a plane on which the first conductor is disposed, the first dielectric being the dielectric being close to the first conductor. Placed close to
The third dielectric is brought close to the second conductor from a plane different from the plane where the first dielectric is close to the second conductor on the plane on which the second conductor is disposed. Placing,
A method of manufacturing a meander line antenna. A method of manufacturing a meander line antenna according to any one of claims 5 to 7,
For at least one of the first and second conductors, forming a line width of a portion with a large amount of flowing current larger than a line width of a portion with a small amount of flowing current;
A method of manufacturing a meander line antenna. A method for manufacturing a meander line antenna according to claim 8,
Forming a line width of at least one of the first and second conductors so as to become farther away from the feeding point;
A method of manufacturing a meander line antenna. An element in which a continuous conductor is repeatedly bent in the opposite direction and arranged in a plane;
A feeding point provided at the center of the element;
A dielectric disposed close to the conductor so as to be sandwiched from both sides of the element;
A meander line antenna comprising: The meander line antenna according to claim 10,
For the conductor, the line width of the portion with a large amount of flowing current is thicker than the line width of a portion with a small amount of flowing current;
A meander line antenna. The meander line antenna according to claim 11,
The line width of the conductor is so thin that it is away from the feeding point,
A meander line antenna. A first element in which a continuous first conductor is repeatedly bent in the opposite direction and arranged in a plane;
A second element that is arranged in the same plane as the plane on which the first conductor is arranged, and is arranged in a plane by repeatedly bending a continuous second conductor in the opposite direction;
A feeding point provided at the center of the first element;
A loop formed by short-circuiting ends of the first and second conductors, and connecting the first and second conductors;
A dielectric disposed adjacent to the loop so as to be sandwiched from both sides of the loop;
A meander line antenna comprising: A first element in which a continuous first conductor is repeatedly bent in the opposite direction and arranged in a plane;
A second element in which a continuous second conductor is repeatedly bent in the opposite direction and arranged in a plane;
A feeding point provided at the center of the first element;
A loop formed by short-circuiting ends of the first and second conductors, and connecting the first and second conductors;
A dielectric adjacent to the first and second conductors so as to be sandwiched between a plane on which the first conductor is disposed and a plane on which the second conductor is disposed;
A meander line antenna comprising: The meander line antenna according to claim 14,
A second dielectric adjacent to the first conductor from a plane different from a plane where the first dielectric, which is the dielectric, is adjacent to the first conductor, on a plane where the first conductor is disposed. Body,
A third dielectric adjacent to the second conductor from a plane different from a plane where the first dielectric is adjacent to the second conductor on a plane on which the second conductor is disposed;
A meander line antenna comprising: The meander line antenna according to any one of claims 10 to 15,
For at least one of the first and second conductors, the line width of the portion where the amount of flowing current is large is thicker than the line width of the portion where the amount of flowing current is small;
A meander line antenna. The meander line antenna according to claim 16,
The line width of at least one of the first and second conductors is so narrow that it is farther from the feeding point;
A meander line antenna.

Images