阅读说明：本技术 天线装置 (Antenna device ) 是由 楠龟大贵 山保威 曾根孝之 塚本真规 于 2018-03-22 设计创作，主要内容包括：被搭载于地板(6)上的天线装置(1)具备天线元件(2)、基座(3)及磁性体(5)。天线元件(2)被搭载于基座(3)上。磁性体(5)被配置在所述基座(3)与地板(6)之间。(An antenna device (1) mounted on a floor (6) is provided with an antenna element (2), a base (3), and a magnetic body (5). The antenna element (2) is mounted on the base (3). The magnetic body (5) is disposed between the base (3) and the floor (6).)

1, kinds of antenna devices, which are mounted on a floor, and which are provided with:

an antenna element;

a base on which the antenna element is mounted;

a magnetic body disposed between the base and the floor.

2. The antenna device of claim 1,

the magnetic body is disposed between the base and glass provided so as to cover at least portions of the floor panel.

3. The antenna device of claim 1 or 2,

the thickness of the magnetic body in the vertical direction is more than 0.1mm, and the imaginary part of the magnetic permeability of the magnetic body is more than 10.

4. The antenna device of claim 1 or 2,

the thickness of the magnetic body in the vertical direction is more than 0.3mm, and the imaginary part of the magnetic permeability of the magnetic body is more than 5.5.

Technical Field

The present disclosure relates to antenna devices mounted on a floor of a vehicle body or the like.

Background

Patent document 1 discloses antenna devices mounted on a vehicle, in which a conductive plate electrically connected to a metal base is brought into contact with vehicle roofs of examples as a floor, and this structure prevents unnecessary resonance caused by the metal base having a resonance point corresponding to the distance from the vehicle roof from occurring in a desired frequency band.

Prior art documents

Patent document

Patent document 1: japanese patent laid-open publication No. 2016-32166

Disclosure of Invention

Problems to be solved by the invention

In the antenna device described in patent document 1, although the unnecessary resonance can be forced out of the desired frequency band, the occurrence of the unnecessary resonance itself cannot be suppressed.

An object of the present disclosure is to provide types of antenna devices capable of suppressing the occurrence of unnecessary resonance.

Means for solving the problems

aspects for achieving the above object are an antenna device mounted on a floor, the antenna device including:

an antenna element;

a base on which the antenna element is mounted;

a magnetic body disposed between the base and the floor.

The magnetic body may be disposed between the base and glass provided so as to cover at least portions of the floor panel.

The thickness of the magnetic body in the vertical direction may be 0.1mm or more, and the imaginary part of the magnetic permeability of the magnetic body may be 10 or more.

The thickness of the magnetic body in the vertical direction may be 0.3mm or more, and the imaginary part of the magnetic permeability of the magnetic body may be 5.5 or more.

Drawings

Fig. 1 is a cross-sectional view schematically showing an antenna device according to embodiment .

Fig. 2 is a frequency characteristic diagram of an average gain obtained by actual measurement for explaining the effect of the magnetic material in the antenna device described above.

Fig. 3 is a frequency characteristic diagram of VSWR obtained by actual measurement for explaining the effect of the magnetic body in the antenna device described above.

Fig. 4 is a diagram schematically showing the configuration of the antenna device used in the simulation shown in fig. 5 to 8.

Fig. 5 is a frequency characteristic diagram of an average gain obtained by simulation of the antenna device described above when the value of the imaginary part μ ″ of the magnetic permeability of the magnetic material is changed.

Fig. 6 is a frequency characteristic diagram of an average gain obtained by simulation of the antenna device described above when the value of the imaginary part μ ″ of the magnetic permeability of the magnetic material thicker than the example of fig. 5 is changed.

Fig. 7 is a frequency characteristic diagram of an average gain obtained by simulation of the antenna device described above when the value of the imaginary part μ ″ of the magnetic permeability of the magnetic material thicker than the example of fig. 6 is changed.

Fig. 8 is a frequency characteristic diagram of an average gain obtained by simulation of the antenna device described above in a case where the longitudinal length of the magnetic body is changed.

Fig. 9 is a characteristic diagram showing a relationship between the imaginary part μ ″ of the magnetic permeability and the minimum value of the average gain, which is obtained by simulation, of the antenna device according to fig. 5.

Fig. 10 is a characteristic diagram showing a relationship between the imaginary part μ ″ of the magnetic permeability and the minimum value of the average gain, which is obtained by simulation, of the antenna device 1 according to fig. 6.

Fig. 11 is a cross-sectional view schematically showing an antenna device according to a second embodiment.

Detailed Description

Hereinafter, examples of the embodiments will be described in detail with reference to the drawings. The same or equivalent components and parts shown in the drawings are denoted by the same reference numerals, and overlapping descriptions are appropriately omitted.

In the drawings, an arrow F indicates a front direction of the illustrated structure. Arrow B indicates the rear direction of the illustrated structure. Arrow U indicates the upward direction of the illustrated structure. Arrow D indicates the downward direction of the illustrated structure. Note that expressions relating to these directions are used for convenience of explanation only, and are not intended to limit the posture of the antenna device when used.

(embodiment )

Fig. 1 is a cross-sectional view schematically showing an antenna device 1 according to embodiment , the antenna device 1 being configured to be mounted on a vehicle, and more specifically, the antenna device 1 being configured to be mounted on a floor 6 such as a vehicle body ceiling.

The antenna device 1 includes an antenna element 2, a base 3, a cylindrical portion 4 for power supply, and a magnetic body 5. In fig. 1, the substrate, electronic components, and the like disposed on the outer case and the base 3 are not illustrated.

In the present example, the antenna element 2 is a TEL antenna. The antenna element 2 is mounted on a metal base 3.

The power feeding cylindrical portion 4 extends downward from the base 3, the power feeding cylindrical portion 4 is electrically connected to the floor panel 6 on the vehicle body side, and the power feeding cylindrical portion 4 may be a metal member integral with the base 3 or may be a separate metal member and electrically connected to the base 3.

The magnetic body 5 is a magnetic sheet, the magnetic body 5 is provided on the lower surface of the base 3, the magnetic body 5 is fixed to the lower surface of the base 3 by adhesion or the like, the magnetic body 5 is disposed so as to be interposed between the base 3 and the floor 6, the magnetic body 5 may be provided on the entire lower surface of the base 3 or may be provided on portion of the lower surface, in the case where the magnetic body 5 is provided on portion of the lower surface of the base 3, it is preferable that the magnetic body 5 is provided at least around the power supply cylindrical portion 4, it is inevitable that a gap is generated between the base 3 and the floor 6 in view of dimensional accuracy, and the magnetic body 5 is provided so as to fill the gap.

Fig. 2 is a frequency characteristic diagram of an average gain obtained by actual measurement for explaining the effect of the magnetic material in the antenna device 1. Fig. 2 shows characteristics of the antenna device 1 having the magnetic material 5 with a high imaginary part μ ″ of magnetic permeability, the antenna device 1 having the magnetic material 5 with a low imaginary part μ ″ of magnetic permeability, and the antenna device of the comparative example in which the magnetic material 5 is removed from the antenna device 1.

Fig. 3 is a frequency characteristic diagram of VSWR obtained by actual measurement for explaining the effect of the magnetic body in the antenna device 1. Fig. 3 shows characteristics of the antenna device 1 having the magnetic material 5 with a high imaginary part μ ″ of the magnetic permeability, the antenna device 1 having the magnetic material 5 with a low imaginary part μ ″ of the magnetic permeability, and the antenna device of the comparative example in which the magnetic material 5 is removed from the antenna device 1.

In the antenna device 1 shown in fig. 2 and 3, a magnetic sheet having a thickness t of 0.5mm in the vertical direction is used as the magnetic material 5, and the value of the real part μ' of the magnetic permeability of the magnetic material 5 is equal to 10 in any antenna device 1, and the value of the imaginary part μ "of the magnetic permeability of the magnetic material 5 is equal to either one of times, i.e., 20(μ" is high) and 10(μ "is low), as shown in fig. 2 and 3, the antenna device 1 can suppress the occurrence of unnecessary resonance regardless of the value of the imaginary part μ" of the magnetic permeability of the magnetic material 5, compared with the case where the magnetic material 5 is not present, by providing the magnetic material 5.

Fig. 4 is a diagram schematically showing the configuration of the antenna device 1 used in the simulation shown in fig. 5 to 8. The base 3 having the magnetic body 5 provided on the lower surface thereof is disposed above the floor 6 with a gap therebetween. Further, the interval between the base 3 and the floor 6 is 1 mm. The antenna element 2 is provided upright on the base 3. The base 3 and the floor 6 are electrically connected to each other through the power supply cylindrical portion 4.

Fig. 5 is a frequency characteristic diagram of an average gain obtained by simulation of the antenna device 1 in a case where the value of the imaginary part μ ″ of the magnetic permeability of the magnetic substance 5 is changed. In each case, the length L of the magnetic body 5 in the front-rear direction was 60 mm. The thickness t of the magnetic body 5 was 0.1 mm. The real part μ 'of the magnetic permeability of the magnetic material 5 has a value μ' of 10. The case where the imaginary part μ "of the magnetic permeability of the magnetic substance 5 has a value of μ" ═ 4, μ "═ 5.5, and μ" ═ 10 is shown.

As is clear from fig. 5, when the thickness t of the magnetic material 5 is 0.1mm, there is no great difference in the average gain at any μ ″ except for the frequencies of 800 to 950MHz, and also , the average gain at side is greatly improved when μ "═ 10 at the frequencies of 800 to 950MHz, compared with the cases where μ" ═ 4 and μ "═ 5.5, therefore, when the thickness t of the magnetic material 5 is 0.1mm, it is preferable that the imaginary part μ ″ of the magnetic permeability is 10 or more, and if the thickness t of the magnetic material 5 is made to be greater than 0.1mm, it is possible to further step suppress the occurrence of unnecessary resonance and further step increase the average gain, and such an example is explained with reference to fig. 6.

Fig. 6 is a frequency characteristic diagram of an average gain obtained by simulation of the antenna device 1 in a case where the value of the imaginary part μ ″ of the magnetic permeability of the magnetic substance 5 having a thickness t of 0.3mm is changed. In each case, the length L of the magnetic body 5 in the front-rear direction was 60 mm. The real part μ 'of the magnetic permeability of the magnetic material 5 has a value μ' of 10. The case where the imaginary part μ "of the magnetic permeability of the magnetic substance 5 has a value of μ" ═ 4, μ "═ 5.5, and μ" ═ 10 is shown.

As is clear from fig. 6, when the thickness t of the magnetic material 5 is 0.3mm, there is no great difference in the average gain at any μ ″ except for the frequencies of 600 to 700MHz, in addition , the average gain at is greatly improved when μ ″ -5.5 and μ ″ -10 are compared to when μ ″ -4 at the frequencies of 600 to 700MHz, and therefore, when the thickness t of the magnetic material 5 is 0.3mm, it is preferable that the imaginary part μ ″ of the magnetic permeability is 5.5 or more, and if the thickness t of the magnetic material 5 is made greater than 0.3mm, it is possible to suppress the occurrence of unnecessary resonance by steps and to further increase the average gain by steps, and such an example is explained with reference to fig. 7.

Fig. 7 is a frequency characteristic diagram of an average gain obtained by simulation of the antenna device 1 in a case where the value of the imaginary part μ ″ of the magnetic permeability of the magnetic substance 5 having the thickness t of 0.5mm is changed. In each case, the length L of the magnetic body 5 in the front-rear direction was 60 mm. The real part μ 'of the magnetic permeability of the magnetic material 5 has a value μ' of 10. The case where the imaginary part μ "of the magnetic permeability of the magnetic substance 5 has a value of μ" ═ 4, μ "═ 5.5, and μ" ═ 10 is shown.

As is clear from fig. 7, when the thickness t of the magnetic material 5 is 0.5mm, there is no great difference in the average gain at any μ ″ except for the frequencies of 550 to 600MHz, in addition , in the case where the frequency is 550 to 600MHz, the average gain at side is greatly improved when μ ″ -5.5 and μ ″ -10 are compared to the case where μ ″ -4, and therefore, in the case where the thickness t of the magnetic material 5 is 0.5mm, it is preferable that the imaginary part μ ″ of the magnetic permeability is 5.5 or more, and according to the above results, if the thickness t of the magnetic material 5 is made to be greater than 0.5mm, it is possible to suppress the occurrence of unnecessary resonance by steps and to improve the average gain by steps.

Fig. 8 is a frequency characteristic diagram of an average gain obtained by simulation of the antenna device 1 in a case where the longitudinal length L of the magnetic body 5 is changed. In each case, the thickness t of the magnetic body 5 was 0.1 mm. The real part μ 'of the magnetic permeability of the magnetic material 5 has a value μ' of 10. The imaginary part μ "of the magnetic permeability of the magnetic substance 5 has a value μ ″, which is 5.5. The longitudinal lengths L of the magnetic body 5 were 60mm, 80mm, 100mm, 120mm and 140 mm.

As is clear from fig. 8, when the longitudinal length L of the magnetic body 5 becomes longer, the frequency of the decrease in the average gain becomes lower. Therefore, it is effective to change the longitudinal length L of the magnetic body 5 in order to push unnecessary resonance out of a desired frequency band.

Fig. 9 is a characteristic diagram showing a result of simulation of a relationship between an imaginary part μ ″ of a magnetic permeability and a minimum value of an average gain in a range of frequencies from 550MHz to 1100MHz in the antenna device 1 according to fig. 5. That is, the longitudinal length L of the magnetic body 5 is 60 mm. The thickness t of the magnetic body 5 was 0.1 mm. The real part μ 'of the magnetic permeability of the magnetic material 5 has a value μ' of 10.

As is clear from fig. 9, the average gain minimum value increases as μ "increases within a range where μ" is 10 or less, and shows the tendency of the average gain minimum value to converge within a range where μ "is 10 or more, and by combining the results of fig. 5 showing the relationship between the average gain and the frequency under the same conditions, it is clear that a high average gain minimum value is obtained by setting the thickness t of the magnetic body 5 to 0.1mm or more and setting the imaginary part μ" of the magnetic permeability to 10 or more.

Fig. 10 is a characteristic diagram showing a result of simulation of a relationship between an imaginary part μ ″ of a magnetic permeability and a minimum value of an average gain in a range of frequencies from 550MHz to 1100MHz in the antenna device 1 according to fig. 6. That is, the longitudinal length L of the magnetic body 5 is 60 mm. The thickness t of the magnetic body 5 was 0.3 mm. The real part μ 'of the magnetic permeability of the magnetic material 5 has a value μ' of 10.

As is clear from fig. 10, the average gain minimum value increases as μ "increases within a range where μ" is 5.5 or less, and shows the tendency of the average gain minimum value to converge within a range where μ "is 5.5 or more, and by combining the results of fig. 6 showing the relationship between the average gain and the frequency under the same conditions, it is clear that a high average gain minimum value is obtained by setting the thickness t of the magnetic body 5 to 0.3mm or more and the imaginary part μ" of the magnetic permeability to 5.5 or more.

As in the example shown in fig. 7, the same tendency is shown in the relationship between the imaginary part μ ″ of the magnetic permeability and the minimum value of the average gain when the thickness t of the magnetic substance 5 is 0.5 mm.

According to the above, by disposing the magnetic body 5 so as to be interposed between the base 3 and the floor 6, the occurrence of unnecessary resonance can be suppressed.

(second embodiment)

Fig. 11 is a cross-sectional view schematically showing an antenna device 1A according to a second embodiment, the antenna device 1A is different from the antenna device 1 according to embodiment in that a vehicle body side glass 7 is present between a base 3 and a floor 6, and a magnetic body 5 is interposed between the base 3 and the glass 7, and the configuration is different, the glass 7 covers at least portion of the floor 6, and the magnetic body 5 is provided so as to fill a gap generated between the base 3 and the glass 7, and according to such a configuration, the same effect as that of the antenna device 1 according to embodiment can be obtained.

The above embodiments are merely examples for facilitating understanding of the present disclosure. The configurations of the above-described embodiments may be appropriately modified or improved as long as they do not depart from the gist of the present disclosure.

As the contents of constituting the description of the present application, japanese patent application laid-open No. 2017-117005, which was proposed 6, 14, 2017, is cited.