JP6865072B2 - Antenna device and electronic device equipped with an antenna device - Google Patents

Description

The present invention relates to an antenna device having a plurality of antenna elements and an electronic device including such an antenna device.

In recent years, as an antenna device for electronic devices such as smartphones and tablet terminals, an antenna device that employs MIMO (Multi-Input Multi-Output) technology has been used in order to increase communication capacity and realize high-speed communication. An antenna device compatible with MIMO technology includes a plurality of (for example, two) antenna elements.

Since the space in the electronic device is limited, when a plurality of antenna devices are housed in the electronic device, the plurality of antenna elements are arranged close to each other. Therefore, interference between antenna elements may occur, and desired antenna performance may not be obtained. Therefore, there is a need for a technique for reducing interference between antenna elements, that is, improving isolation between antenna elements.

Patent Document 1 provides a housing in which a conductive layer that functions as an electromagnetic wave shielding layer is formed on an inner surface and a conductive layer on the back surface in order to provide an electronic device capable of reducing radio wave interference between antennas. A flat panel display housed in the housing so as to face the antenna, and a portion of the flat panel display arranged between the back surface of the flat panel display and the conductive layer at a predetermined distance from the surface of the conductive layer. Between the first antenna arranged so as to be located on the outer peripheral side of the side of the conductive layer and the back surface of the flat panel display and the conductive layer at a predetermined distance from the surface of the conductive layer. It includes a second antenna arranged and partially arranged so as to be located on the outer peripheral side of the side of the conductive layer, and the conductive layer comprises the first antenna and the second antenna. An electronic device having a notch formed at a predetermined position on the side of the conductive layer and having a length of 1/4 of a wavelength corresponding to the resonance frequency of the first antenna is disclosed. There is.

Patent Document 2 describes a wireless terminal having a ground conductor and a transmitter / receiver, wherein the transmitter / receiver includes at least two antenna feeders and at least two parallel plate capacitors, and each of the parallel plate capacitors is insulated from each other. Each of the first plates comprises a conductor plate insulated from the ground conductor, and each of the second plates comprises the ground under the conductor plate. Each of the at least two antenna feeders, including a portion of the surface of the conductor, is connected between the corresponding conductor plate and the corresponding radio frequency output / input, and the second plate each provides an impedance conversion. Disclosed are wireless terminals characterized in that they are separated from each other by a groove.

Patent Document 3 provides a conductor plate and the end of the conductor plate in order to provide an antenna device capable of saving space or miniaturization while maintaining a certain characteristic as an antenna element by reducing interference between antenna elements. At least two antenna elements arranged in the vicinity of the unit, a first slot line having a characteristic impedance formed on the conductor plate having an arbitrary value Z1, and an arbitrary characteristic impedance formed on the conductor plate having a characteristic impedance larger than Z1. A second slot line having a value of Z2 is provided, and one end of the first slot line is an open end in a region between the antenna elements in the end of the conductor plate, and the first slot line. An antenna device is disclosed in which the other end is connected to one end of the second slot line and the other end of the second slot line is short-circuited inside the conductor plate. According to this, as compared with the case of forming a slot line having a line length of 1/4 of the wavelength corresponding to the resonance frequency of the antenna element, the total line length of the first slot line and the second slot line is Since interference between antenna elements can be reduced in a shorter state, an antenna device capable of saving space or miniaturization while maintaining certain characteristics as an antenna element is provided.

Japanese Patent No. 4738380 Japanese Patent No. 4347567 International Publication No. 2013/140770

In the technique described in Patent Document 1, when the distance between the antennas is small (for example, less than 1/4 of the wavelength corresponding to the resonance frequency of the antenna), the notch portion operates as a non-feeding notch antenna. Due to the secondary radiation from the antenna, the isolation between the antennas is rather deteriorated.

In the technique described in Patent Document 2, at least two grooves corresponding to at least two parallel plate capacitors need to be provided in the ground conductor. Therefore, when the ground conductor forms a circuit board, the circuit element mounted on the circuit board The layout is greatly restricted, and if the ground conductor is a housing, the rigidity of the housing may decrease.

With the technique described in Patent Document 3, it may be possible to shorten the total length of the first and second slot lines (slits) formed on the conductor plate, but in particular, the characteristic impedance of the second slot line. Since it is necessary to increase the width of the second slot line in order to set Z2 to a desired value, the area occupied by the conductor plate becomes large. Moreover, the structure of the slit becomes complicated.

The present invention has first and second antenna elements having substantially the same operating frequency band, and good antenna-to-antenna isolation with a simple structure even when the distance between the first and second antenna elements is small. An object of the present invention is to provide an antenna device capable of obtaining the above-mentioned antenna device, and an electronic device provided with such an antenna device.

The antenna device of the present invention has a ground conductor, first and second feeding points arranged on the ground conductor or in the vicinity of the ground conductor at a distance from each other, and the first and second feeding points, respectively. From the first and second antenna elements that are electrically connected and have substantially the same operating frequency band, the strip-shaped region of the ground conductor extending along the surface of the ground conductor, and the strip-shaped region of the ground conductor. Between the band-shaped conductor that extends along the band-shaped region at a distance and constitutes a non-feeding antenna that resonates with the band-shaped region in the operating frequency band, and the band-shaped region and the band-shaped conductor of the ground conductor. It has a connected resistance element.

Further, the electronic device of the present invention is electrically connected to the antenna device to the first and second feed points of the antenna device via the first and second feeder lines, and is electrically connected to the first and second feed points of the antenna device via the antenna device. It is equipped with a wireless communication unit that communicates with the outside.

According to the present invention, there are first and second antenna elements having substantially the same operating frequency band, and even when the distance between the first and second antenna elements is small, a simple structure is sufficient between the antennas. Antenna devices capable of obtaining isolation and electronic devices equipped with such antenna devices are provided.

A block diagram showing a schematic configuration of an electronic device provided with an antenna device according to the first embodiment. Top view showing the antenna device which concerns on 1st Embodiment Perspective view of the antenna device shown in FIG. Isolation characteristics between antenna elements with respect to the resistance value of the resistance elements shown in FIGS. 1 and 2 (left vertical axis), and antenna efficiency of the first and second antenna elements with respect to the resistance value of the resistance element (right vertical axis). Diagram showing In the antenna device of the first embodiment, the frequency characteristics of the isolation between the antenna elements when the resistance value of the resistance element is 100Ω are set to Comparative Example 1 (except that the notch formed in the ground conductor and the resistance element are not provided). The figure which shows in comparison with the antenna device of the same structure as the antenna device of 1st Embodiment) The figure which shows the antenna efficiency at the time of the resistance value of a resistance element of 100Ω in the antenna device of 1st Embodiment in comparison with the comparative example 1. FIG. Top view showing the current distribution when power is supplied to the second antenna element at a frequency within the operating frequency band in Comparative Example 1. Current when power is supplied to the second antenna element at a frequency within the operating frequency band in Comparative Example 2 (antenna device having the same configuration as the antenna device of the first embodiment except that the resistance element is not arranged in the notch). Plan view showing distribution Top view showing the current distribution when power is supplied to the second antenna element at a frequency within the operating frequency band in the antenna device of the first embodiment. Top view showing the antenna device which concerns on 2nd Embodiment A perspective view showing an antenna device according to a third embodiment. Sectional drawing of the antenna device along line XII-XII of FIG. Schematic diagram showing an example of the electric field distribution around the notch Schematic diagram showing an example of the magnetic field distribution around the notch Top view of the antenna device according to the fourth embodiment Perspective view of the antenna device shown in FIG. FIG. 6 is a schematic view of a main part showing a modified example of the antenna device shown in FIG.

The antenna device according to the first invention, which has been made to solve the above problems, includes a ground conductor and first and second feeding points arranged on the ground conductor or in the vicinity of the ground conductor so as to be separated from each other. , The first and second antenna elements electrically connected to the first and second feeding points, respectively, and having substantially the same operating frequency band, a notch formed on one side of the ground conductor, and the ground. A band-shaped region in the ground conductor extending along the surface of the conductor and a band-shaped region extending along the band-shaped region away from the band-shaped region of the ground conductor, and resonating with the band-shaped region in the operating frequency band. It has a strip-shaped conductor that constitutes a non-feeding antenna, and a resistance element that connects the strip-shaped region of the ground conductor facing the ground conductor and the strip-shaped conductor via the notch.

According to this configuration, when power is supplied to one of the first and second antenna elements at a frequency within the operating frequency band, the band-shaped conductor extending along the band-shaped region apart from the band-shaped region of the ground conductor and the band-shaped region. Since the mutual impedance between the first and second antenna elements can be increased by the non-feeding antenna and the resistance element composed of the above, even if the distance between the first and second antenna elements is small, the first and first antenna elements The current generated in the other of the two antenna elements can be reduced. That is, the isolation between the first and second antenna elements can be improved. Further, this configuration can be realized by a simple configuration in which a resistance element is connected between the band-shaped region of the ground conductor and the band-shaped conductor. Therefore, even when the first and second antenna elements having substantially the same operating frequency band are provided and the distance between the first and second antenna elements is small, good antenna-to-antenna isolation can be obtained with a simple structure. It is possible to provide an antenna device capable of providing an antenna device.

Further, in the second invention, the strip-shaped region of the grounding conductor is separated by a notch formed on one side of the grounding conductor, and is separated from one of a pair of regions of the grounding conductor facing each other through the notch. The strip-shaped conductor comprises the other of the pair of regions of the ground conductor facing each other through the notch.

According to this configuration, a non-feeding antenna that resonates in the operating frequency band of the first and second antenna elements is realized by a simple configuration in which a notch is formed on one side of the ground conductor, and the isolation between antennas is improved. be able to.

Further, in the third invention, the notch has a length of approximately 1/4 of the wavelength corresponding to the representative frequency of the operating frequency band.

According to this configuration, the operating frequency band of the antenna element is a non-feeding antenna composed of notches (or a pair of regions of ground conductors that are separated by the notches and face each other) while shortening the length of the notches. It is possible to easily resonate in the antenna element and improve the isolation between antenna elements in the operating frequency band.

Further, in the fourth invention, the first and second antenna elements are arranged in the vicinity of the one side of the ground conductor, and the first and second feeding points are in directions along the one side of the ground conductor. The notch is formed at a position between the first feeding point and the second feeding point on the one side.

According to this configuration, the isolation effect between the first and second antenna elements due to the notch is further improved.

Further, in the fifth invention, at least one of the first and second antenna elements is arranged in the vicinity of the one side of the ground conductor and has a portion extending along the one side of the ground conductor. The dimension in the direction perpendicular to one side is less than about 1/10 of the wavelength corresponding to the representative frequency of the operating frequency band.

According to this configuration, a decrease in antenna efficiency of at least one of the first and second antenna elements due to the notch formed in the ground conductor is suppressed.

Further, in the sixth invention, the dielectric material or the magnetic material is arranged in the notch, and the thickness of the dielectric material or the magnetic material is larger than the thickness of the ground conductor.

According to this configuration, due to the wavelength shortening effect of the dielectric material or the magnetic material, the length of the notch can be shortened as compared with the case where the dielectric material or the magnetic material is not arranged in the notch. ..

Further, in the seventh invention, the strip-shaped conductor is a member different from the grounding conductor, and is separated from the strip-shaped region of the grounding conductor in a direction away from the surface of the grounding conductor, and the strip-shaped conductor of the grounding conductor is separated from the strip-shaped region. It is arranged to face the area.

According to this configuration, it is possible to realize a non-feeding antenna that resonates in the operating frequency band of the first and second antenna elements without forming a notch in the ground conductor, and to improve the isolation between the antennas.

Further, in the eighth invention, the band-shaped conductor has a length of about 1/4 of the wavelength corresponding to the representative frequency of the operating frequency band.

According to this configuration, while shortening the length of the band-shaped conductor, the non-feeding antenna composed of the band-shaped conductor (or the band-shaped region of the band-shaped conductor and the ground conductor) easily resonates in the operating frequency band of the antenna element, and the operating frequency. Isolation between antenna elements in the band can be improved.

Further, in the ninth invention, the first and second antenna elements are arranged in the vicinity of one side of the ground conductor, and the first and second feeding points are in the direction along the one side of the ground conductor. Separated from each other, one end of the strip-shaped conductor is located between the first feeding point and the second feeding point.

According to this configuration, the isolation between the first and second antenna elements is further improved.

Further, in the tenth invention, the capacitance element is connected in parallel with the resistance element.

According to this configuration, the strip-shaped region of the ground conductor constituting the non-feeding antenna and the length of the strip-shaped conductor extending along the strip-shaped region (the strip-shaped region and the strip-shaped conductor are a pair of ground conductors facing each other through the notch. The length of the notch) can be shortened as compared with the case where the capacitive element is not connected.

Further, in the eleventh invention, the band-shaped region of the ground conductor constituting the non-feeding antenna and at least a part of the band-shaped conductor are formed from the second feeding point or the open end of the second antenna element. It is located at a distance of less than about 1/4 of the wavelength corresponding to the representative frequency of the operating frequency band.

According to this configuration, when power is supplied to the second antenna element at a frequency within the operating frequency band, the non-feeding antenna and the second antenna element composed of the band-shaped region of the ground conductor and the band-shaped conductor extending along the band-shaped conductor are formed. It is possible to reduce the current generated in the first antenna element by binding strongly electromagnetically.

Further, in the twelfth invention, the distance between the first feeding point and the second feeding point is less than about 1/4 of the wavelength corresponding to the representative frequency of the operating frequency band.

According to this configuration, when the distance between the first feeding point and the second feeding point is less than about 1/4 of the wavelength corresponding to the representative frequency of the operating frequency band, the first and second antennas Isolation between elements can be improved.

Further, in the thirteenth invention, the resistance value of the resistance element is the resonance of the non-feeding antenna composed of the band-shaped region of the ground conductor and the band-shaped conductor measured at the position where the resistance element is connected. Approximately equal to the input impedance at frequency.

According to this configuration, the isolation between the first and second antenna elements can be reliably improved.

Further, the electronic device according to the fourteenth invention is electrically connected to the antenna device and the first and second feeding points of the antenna device via the first and second feeding lines, and the antenna. It includes a wireless communication unit that communicates with the outside via the device.

According to this configuration, there are first and second antenna elements having substantially the same operating frequency band, and even when the distance between the first and second antenna elements is small, a good inter-antenna iso with a simple structure It is possible to provide an electronic device provided with an antenna device capable of obtaining a frequency.

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

(First Embodiment)
FIG. 1 is a block diagram showing a schematic configuration of an electronic device including the antenna device according to the first embodiment. The electronic device 1 shown in FIG. 1 is, for example, a smartphone or a tablet terminal. As shown in FIG. 1, the electronic device 1 includes an input unit 2 for inputting a user's instruction, an output unit 3 for outputting information such as an image and sound, and a memory 4 for storing a program and data. , A controller (processor) 5 that operates based on a program stored in the memory 4 and processes an operation signal input from the input unit 2 and controls the output unit 3, and an antenna device under the control of the controller 5. It has a wireless communication unit 7 that performs wireless communication with the outside via 6. The input unit 2 includes, for example, a touch panel and a microphone. The output unit 3 includes, for example, a liquid crystal display and a speaker.

The antenna device 6 electrically connects to the wireless communication unit 7 via the first antenna element 10 electrically connected to the wireless communication unit 7 via the first feeder line 8 and the wireless communication unit 7 via the second feeder line 9. It has a second antenna element 11 connected to it. The connection point between the first feed line 8 and the first antenna element 10 is the first feed point 12, and the connection point between the second feeder 9 and the second antenna element 11 is the second. It is a feeding point 13. The first and second antenna elements 10 and 11 are adapted to have substantially the same operating frequency band (in this example, about 718 to 890 MHz used in cellular systems, but not limited to). ..

Next, the configuration of the antenna device 6 will be described in detail. FIG. 2 is a plan view showing the antenna device 6 according to the first embodiment, and FIG. 3 is a perspective view of the antenna device 6 shown in FIG.

As shown in FIGS. 2 and 3, the antenna device 6 has a substantially rectangular ground conductor (also referred to as a main plate) 21 having a flat surface provided on the first surface of the substrate 20 mainly made of an insulator. ing. The first and second antenna elements 10 and 11 are arranged in the vicinity of the upper side 22 of the ground conductor 21. The first antenna element 10 is composed of a plate-shaped inverted F antenna. The second antenna element 11 is composed of a low-profile inverted L antenna, and has a portion extending along the upper side 22 of the ground conductor 21. Here, "low profile" means that the dimension in the direction perpendicular to the upper side 22 is a representative frequency of the operating frequency band of the antenna elements 10 and 11 (760 MHz in this example, but if the frequency is within the operating frequency band, it is different. It may be a frequency, which means that it is less than about 1/10 of the wavelength corresponding to, for example, the center frequency (804 MHz in this example). The first and second antenna elements 10 and 11 may be the same type of antenna elements. The grounding conductor 21 is made of, for example, a copper foil or a grounding pattern printed on the substrate 20. The ground conductor 21 does not necessarily have to be provided on the substrate 20, and may be provided, for example, in the housing of the electronic device 1.

Although not shown, wiring is printed on the second surface of the substrate 20 opposite to the first surface. That is, in the present embodiment, the substrate 20 is configured as a printed wiring board. The circuit modules and circuit elements constituting the memory 4, the controller 5, the wireless communication unit 7, and the like shown in FIG. 1 are mounted on the second surface of the substrate 20. The wireless communication unit 7 is connected to the first and second antenna elements 10 and 11 by the first and second feeder lines 8 and 9 on the second surface side of the substrate 20.

As shown in FIG. 2, in the present embodiment, the first feeding point 12 is located on the ground conductor 21 near the right end of the upper side 22 of the ground conductor 21 (that is, overlaps with the ground conductor 21 in a plan view). ing). Further, the second feeding point 13 is located on the ground conductor 21 near the left end of the upper side 22 of the ground conductor 21 (that is, overlaps with the ground conductor 21 in a plan view). As a result, the first feeding point 12 and the second feeding point 13 are separated from each other and are located on the ground conductor 21. In this example, the distance between the first feeding point 12 and the second feeding point 13 is approximately 1/4 of the wavelength corresponding to the representative frequency of the operating frequency bands of the first and second antenna elements 10 and 11. It is smaller than (about 98.6 mm when the representative frequency is 760 MHz) (for example, about 50 mm). The first feeding point 12 and the second feeding point 13 do not necessarily have to be located on the grounding conductor 21, and are arranged in the vicinity of the grounding conductor 21 so as not to overlap the grounding conductor 21 in a plan view. May be good. Further, in FIG. 3, the symbols indicating the feeding points 12 and 13 are omitted in order to clearly indicate the shapes of the antenna elements 10 and 11.

The position between the first feeding point 12 and the second feeding point 13 on the upper side 22 of the ground conductor 21 of the antenna device 6 extends in the direction intersecting the upper side 22 (vertical direction in this example). A notch (slit) 30 is formed. The notch 30 includes a first end 31 (see FIG. 3) opened at the upper side 22, a second end 32 closed at a position away from the upper side 22, and a first end 31 and a second end. It has a pair of side edges 33, 34 that face each other and extend to and from the portion 32. The portions of the grounding conductors 21 extending along the side edges 33 and 34 of the notch 30 form a pair of regions 25 and 26 of the grounding conductors that are separated by the notch 30 and face each other through the notch 30. There is. Each of the regions 25 and 26 is a band-shaped region along the notch 30. Such a notch 30 (or a pair of regions 25 and 26 of the ground conductors 21 facing each other through the notch 30) constitutes a non-feeding antenna (non-feeding notch antenna). Here, one of the pair of regions 25 and 26 of the ground conductor 21 facing each other through the notch 30 is an example of the "belt-shaped region in the ground conductor" of the present invention, and the other is separated from the "belt-shaped region" of the present invention. This is an example of a "belt-shaped conductor extending along a strip-shaped region".

The length from the first end portion 31 to the second end portion 32 of the notch 30 is set to approximately 1/4 of the wavelength corresponding to the representative frequency of the operating frequency band of the antenna elements 10 and 11. As a result, the non-feeding antenna configured by the notch 30 resonates in the operating frequency band. In order to make the length of the notch 30 as small as possible and to make it easier for the non-feeding antenna composed of the notch 30 to resonate in the operating frequency band of the antenna elements 10 and 11, the length of the notch 30 should be set to the operating frequency. It is preferable that the wavelength corresponding to the representative frequency of the band is approximately 1/4, but if space can be secured, the length of the notch 30 may be set to approximately 1/2 of the wavelength corresponding to the representative frequency of the operating frequency band. It may be the length of.

Further, at least a part of the pair of regions 25 and 26 of the ground conductor 21 facing each other through the notch 30 constituting the non-feeding antenna is from the second feeding point 13 or the open end 11a of the second antenna element 11. , It is located at a distance of less than about 1/4 of the wavelength corresponding to the representative frequency of the operating frequency band (in this example, equal to the length of the notch 30).

Further, at the first end portion 31, which is the open end of the notch 30, a resistance element 40 connected between a pair of regions 25 and 26 of ground conductors facing each other via the notch 30 is arranged. ..

FIG. 4 shows the isolation characteristics (left vertical axis) between the antenna elements with respect to the resistance value of the resistance element 40 shown in FIGS. 1 and 2, and the first and second antenna elements 10 with respect to the resistance value of the resistance element 40. It is a figure which shows the antenna efficiency (right vertical axis) of eleven.

In FIG. 4, S21 is the coupling coefficient of the second antenna element 11 with respect to the first antenna element 10, and the smaller the value of the coupling coefficient S21, the better the isolation. The coupling coefficient S21 changes depending on the operating frequencies of the antenna elements 10 and 11. In FIG. 4, the circular marker indicates the average value (sometimes referred to as the isolation average value) of the coupling coefficient S21 in the operating frequency band of the antenna elements 10 and 11, and the diamond-shaped marker indicates the operation. The maximum value of the coupling coefficient S21 in the frequency band (sometimes referred to as the minimum isolation value) is shown for each resistance value. Further, in FIG. 4, the square marker indicates the average value of the antenna efficiency of the first antenna element 10 in the operating frequency band for each resistance value, and the triangular marker indicates the antenna of the second antenna element 11 in the operating frequency band. The average value of efficiency is shown for each resistance value.

As shown in FIG. 4, the value of the coupling coefficient S21 changes depending on the resistance value of the resistance element 40. For example, when the resistance value of the resistance element 40 is about 300Ω, the value of the coupling coefficient S21 is the maximum value ( Both the diamond-shaped marker) and the average value (circular marker) are significantly lower than when the resistance value of the resistance element 40 is about 900Ω. That is, when the resistance value of the resistance element 40 is about 300Ω, the isolation between the antennas is greatly improved as compared with the case where the resistance value of the resistance element 40 is about 900Ω. Here, the larger the value of the resistance element 40 (that is, the closer to the right side of FIG. 4), the closer to the case where the resistance element 40 is not provided (that is, the resistance value of the resistance element 40 is infinite). As described above, in the antenna device 6 of the first embodiment, the resistance element 40 is connected between the pair of regions 25 and 26 of the ground conductor 21 facing each other through the notch 30 formed in the ground conductor 21. As compared with the case where the resistance element 40 is not provided, the isolation between the antennas can be improved.

Table 1 shows that power is supplied at the first end 31 (that is, the connection position of the resistance element 40) of the notch 30 while changing the frequency within the operating frequency band of the first and second antenna elements 10 and 11 (that is,). The input impedance of the non-feeding antenna (notch antenna) composed of the notch 30 measured by applying a signal) is shown.

In Table 1, R indicates the resistance component of impedance, and X indicates the reactance component of impedance. As shown in Table 1, in this example, the non-feeding antenna (notch antenna) composed of the notch 30 resonates at about 760 MHz, which is a representative frequency of the operating frequency band of the antenna elements 10 and 11, and the reactance component X Is almost zero, and then the input impedance is substantially equal to the value of the resistance component R, which is about 346.6Ω. This is because, as described above, the length of the notch 30 is set to approximately 1/4 of the wavelength corresponding to 760 MHz. According to an experiment by the inventor of the present invention, the resistance value of the resistance element 40 is measured at the position where the resistance element 40 is connected, and the input impedance at the resonance frequency of the non-feeding antenna composed of the notch 30 (in this example). , Approximately 346.6Ω), it was found that the antenna-to-antenna isolation was approximately maximized (ie, the coupling coefficient S21 was minimized). However, as shown in FIG. 4, since the effect of improving isolation can be seen over a relatively wide range (about 100 to 600 Ω) of the resistance value of the resistance element 40, the resistance value of the resistance element 40 is isolated. It may be appropriately selected according to the required specifications from the range in which the effect of improvement can be obtained.

Referring to FIG. 4 again, in the resistance value of the resistance element 40 for which the isolation is improved is in the range of about 100 to 600Ω, the antenna efficiency of the first antenna element 10 in the first embodiment does not provide the resistance element 40. Although it is slightly higher than the case (which is considered to be substantially equal to the value at the right end in FIG. 4), the antenna efficiency of the second antenna element 11 in the first embodiment is higher than that in the case where the resistance element 40 is not provided. It has decreased slightly. It is considered that the decrease in antenna efficiency in the second antenna element 11 is due to the current being consumed as heat in the resistance element 40. However, when the resistance value of the resistance element 40 is in the range of about 100 to 600Ω, the amount of decrease in antenna efficiency of the second antenna element 11 due to the provision of the resistance element 40 is the isolation between the antenna elements due to the provision of the resistance element 40. It is sufficiently small compared to the amount of improvement.

FIG. 5 shows the frequency characteristics of the isolation between the antenna elements (coupling coefficient S21) when the resistance value of the resistance element 40 is 100Ω in the antenna device 6 of the first embodiment, and is formed on the ground conductor 21. It is a figure which shows in comparison with (the antenna device which has the same structure as the antenna device 6 of 1st Embodiment) except that it does not have a notch 30 and a resistance element 40. As shown in FIG. 5, in the first embodiment, as compared with Comparative Example 1, not only the resonance frequency of 760 MHz of the non-feeding notch antenna configured by the notch 30, but also the operation of the antenna elements 10 and 11 is performed. Isolation is improved (coupling coefficient S21 is lowered) in a wide frequency band including the frequency band of 718 to 890 MHz.

FIG. 6 is a diagram showing the antenna efficiency when the resistance value of the resistance element 40 is 100Ω in the antenna device 6 of the first embodiment in comparison with Comparative Example 1. In FIG. 6, the antenna efficiency of each antenna element is an average value in the operating frequency band (718 to 890 MHz) of the antenna element. As shown in FIG. 6, the antenna efficiency of the first antenna element 10 in the first embodiment is slightly lower than that of Comparative Example 1 (that is, an antenna device in which neither the notch 30 nor the resistance element 40 is provided). The antenna efficiency of the second antenna element 11 in the first embodiment is slightly higher than that of Comparative Example 1. The amount of decrease in antenna efficiency of the first antenna element 10 due to the provision of the notch 30 and the resistance element 40 is the amount of improvement in isolation between the antenna elements due to the provision of the notch 30 and the resistance element 40 (FIGS. 4 and 4). 5) is sufficiently small compared to). The antenna efficiency of the second antenna element 11 in the first embodiment is slightly higher than that of Comparative Example 1. The effect of reducing the antenna efficiency due to the provision of the resistance element 40 is cut out 30. It is considered that the effect of improving the antenna efficiency due to the decrease in the electromagnetic coupling between the antenna elements was exceeded.

Here, in the antenna device 6 of the first embodiment, the antenna efficiency of the second antenna element 11 does not decrease (rather, it is slightly improved) because the second antenna element 11 is composed of a low-profile antenna. That is, the second antenna element 11 has a portion extending along the upper side 22 (that is, the side on which the notch 30 is formed) of the ground conductor 21, and the dimension in the direction perpendicular to the upper side 22 is the antenna. It is also considered that one of the reasons is that the wavelength is less than about 1/10 of the wavelength corresponding to the representative frequency of the operating frequency band of the elements 10 and 11. This is because when the ground conductor 21 is not provided with the notch 30, when power is supplied to the second antenna element 11 composed of a low-profile inverted L antenna, the upper side 22 of the ground conductor 21 of the second antenna element 11 is fed. The current flowing along the extending portion and the current flowing along the upper side 22 of the ground conductor 21 are canceled, and the current flowing along the upper side 22 is the radiation of the radio wave from the second antenna element 11 (far field radiation). ), And the second antenna element 11 mainly emits radio waves by a current in the direction perpendicular to the upper side 22, so that a notch 30 is formed in the upper side 22 of the ground conductor 21 as in the first embodiment. This is because even if the resistance element 40 is provided there, the influence on the radio wave (that is, the antenna efficiency) radiated from the second antenna element 11 is small.

FIG. 7 is a plan view showing a current distribution when power is supplied to the second antenna element 11 at a frequency within the operating frequency band in Comparative Example 1. As shown in FIG. 7, in the antenna device of Comparative Example 1 in which the notch 30 and the resistance element 40 are not provided, when the second antenna element 11 is fed at a frequency within the operating frequency band, the second antenna element 11 is supplied. The antenna current of the antenna element 11 flows through the ground conductor 21, particularly along the upper side 22 of the ground conductor 21, to the first antenna element 10, and the current is distributed to the first antenna element 10. That is, the isolation between the first and second antenna elements 10 and 11 is not sufficient, and interference occurs between these antenna elements.

FIG. 8 shows a second antenna having a frequency within the operating frequency band in Comparative Example 2 (an antenna device having the same configuration as the antenna device 6 of the first embodiment except that the resistance element 40 is not arranged in the notch 30). It is a top view which shows the current distribution when power is supplied to the element 11. As shown in FIG. 8, the antenna device of Comparative Example 2 is composed of a notch 30 formed in the ground conductor 21 when the second antenna element 11 is fed with a frequency within the operating frequency band. The notch antenna resonates, and the current is distributed along a pair of regions 25 and 26 of the ground conductors 21 facing each other through the notch 30. In Comparative Example 1, it is considered that the notch 30 formed in the ground conductor 21 suppresses the current coupling between the first and second antenna elements 10 and 11 through the ground conductor 21 as compared with Comparative Example 1. In addition, a large amount of current is distributed in the first antenna element 10. It is considered that this is due to the influence of the secondary radiation from the notch antenna (notch 30).

FIG. 9 is a plan view showing a current distribution when power is supplied to the second antenna element 11 at a frequency within the operating frequency band in the antenna device 6 of the first embodiment. As shown in FIG. 9, also in the antenna device 6 of the first embodiment, when the second antenna element 11 is fed with a frequency within the operating frequency band, the ground conductor 21 is formed as in the case of Comparative Example 2. The notch antenna composed of the notch 30 resonates, and the current is distributed along the pair of regions 25 and 26 of the ground conductors 21 facing each other through the notch 30. However, since the resistance element 40 connected between the pair of regions 25 and 26 of the ground conductors 21 facing each other through the notch 30, the resistance elements 40 are provided, so that the first and second antenna elements 10 and 11 are mutually connected. Impedance is increased and electromagnetic coupling due to secondary radiation due to resonance of the notch antenna is reduced. As a result, the current distributed in the first antenna element 10 is significantly reduced as compared with Comparative Examples 1 and 2. That is, according to the first embodiment, when the first and second antenna elements 10 and 11 having substantially the same operating frequency band are provided and the distance between the first and second antenna elements 10 and 11 is small. However, an antenna device 6 capable of obtaining good antenna-to-antenna isolation with a simple structure is provided. The current distributions shown in FIGS. 7 to 9 were measured by feeding power at 760 MHz as a frequency within the operating frequency band.

Further, the antenna device 6 of the first embodiment has a simple configuration in which a notch 30 is formed on one side (upper side 22) of the ground conductor 21 in the operating frequency bands of the first and second antenna elements 10 and 11. It is possible to realize a resonating non-feeding antenna and improve the isolation between antennas.

Further, as described above, the notch 30 has a length of approximately 1/4 of the wavelength corresponding to the representative frequency (760 MHz in this example) of the operating frequency band of the antenna elements 10 and 11, and thus the length of the notch 30. The non-feeding antenna composed of the notch 30 (or a pair of regions 25 and 26 of the ground conductors 21 which are separated by the notch 30 and face each other) is the operating frequency band of the antenna elements 10 and 11. It is possible to easily resonate in the antenna element and improve the isolation between antenna elements in the operating frequency band.

Further, as described above, in the antenna device 6 of the first embodiment, the first and second antenna elements 10 and 11 are arranged in the vicinity of one side (upper side 22) of the ground conductor 21, and the first and second power supplies are supplied. The points 12 and 13 are separated from each other in the direction along the upper side 22 of the ground conductor 21, and the notch 30 is formed at a position between the first feeding point 12 and the second feeding point 13 on the upper side 22. Therefore, the isolation effect between the first and second antenna elements 10 and 11 due to the notch 30 is further improved.

Further, as described above, in the antenna device 6 of the first embodiment, the second antenna element 11 extends a portion extending along the upper side 22 (that is, the side on which the notch 30 is formed) of the ground conductor 21. Since the dimension in the direction perpendicular to the upper side 22 is less than about 1/10 of the wavelength corresponding to the representative frequency of the operating frequency band of the antenna elements 10 and 11, the notch 30 formed in the ground conductor 21 The decrease in antenna efficiency of the second antenna element 11 due to the above is suppressed. The first antenna element 10 has a portion extending along the side of the ground conductor 21 in which the notch 30 is formed, and the dimension in the direction perpendicular to the side corresponds to the representative frequency of the operating frequency band. A low-profile antenna (for example, an inverted L antenna) having a size of less than about 1/10 of the wavelength to be used may be used.

Further, as described above, in the antenna device 6 of the first embodiment, the resistance value of the resistance element 40 is measured at the position where the resistance element 40 is connected, and is separated from each other by the notch 30 (or the notch 30). Since it is substantially equal to the input impedance (about 346.4 Ω in this example) at the resonance frequency of the non-feeding antenna (notch antenna) composed of the pair of regions 25 and 26) of the ground conductor 21, the first and second The isolation between the antenna elements 10 and 11 can be reliably improved.

Further, as described above, in the antenna device 6 of the first embodiment, at least a part of the pair of regions 25 and 26 of the ground conductors 21 facing each other through the notch 30 constituting the non-feeding antenna is the second feeding. Approximately 1/4 of the wavelength corresponding to the representative frequency of the operating frequency band of the antenna elements 10 and 11 from the open end 11a of the point 13 or the second antenna element 11 (in this example, it is equal to the length of the notch 30). Since it is located at a distance less than, when power is supplied to the second antenna element 11 at a frequency within the operating frequency band, the pair of regions 25 of the ground conductors 21 facing each other through the notch 30 (or the notch 30). The non-feeding antenna configured by 26) and the second antenna element 11 are strongly electromagnetically coupled to each other, and the current generated in the first antenna element 10 can be reduced.

(Second Embodiment)
Next, the second embodiment of the present invention will be described. FIG. 10 is a plan view showing the antenna device according to the second embodiment. It should be noted that the points not particularly mentioned in the description of the second embodiment are the same as those of the first embodiment described above.

As shown in FIG. 10, the antenna device 6a of the second embodiment is different from the antenna device 6 of the first embodiment in that the capacitance element 41 is connected in parallel with the resistance element 40. By configuring the capacitance element 41 connected in parallel with the resistance element 40 in this way, the resonance frequency of the notch antenna configured by the notch 30 is set to the same value as that of the antenna device 6 of the first embodiment (for example, 760 MHz). ), The length of the notch 30 can be shortened. As a result, the strength decrease of the grounding conductor 21 due to the notch 30 is suppressed, and the circuit on the surface (second surface) opposite to the surface (first surface) on which the grounding conductor 21 of the substrate 20 is arranged. The influence of the notch 30 on the mounting of the module or the like is reduced.

(Third Embodiment)
Next, a third embodiment of the present invention will be described. FIG. 11 is a perspective view showing the antenna device according to the third embodiment, and FIG. 12 is a cross-sectional view of the antenna device along the line XII-XII of FIG. FIG. 13A is a schematic diagram showing an example of the electric field distribution around the notch, and FIG. 13B is a schematic diagram showing an example of the magnetic field distribution around the notch. It should be noted that the points not particularly mentioned in the description of the third embodiment are the same as those of the first embodiment.

As shown in FIGS. 11 and 12, the antenna device 6b of the third embodiment is arranged near the first antenna element 110 arranged near the lower side 23 of the ground conductor 21 and near the upper side 22 of the ground conductor 21. It has a second antenna element 111 and the like. The first and second antenna elements 110 and 111 have substantially the same operating frequency band (for example, 718 to 890 MHz). The first and second antenna elements 110 and 111 are both composed of a low profile inverted L antenna. As described above, in the antenna device 6b of the third embodiment, the first and second antenna elements 110 and 111 are arranged in the vicinity of different sides of the ground conductor 21.

Further, in the antenna device 6b, a material 50 made of a dielectric or a magnetic material is arranged in a notch 30 (see also FIGS. 2 and 3) formed on the upper side 22 of the ground conductor 21. As is well shown in FIG. 12, a notch 28 is also formed in a portion of the substrate 20 aligned with the notch 30 of the ground conductor 21. The material 50 has a thickness larger than the thickness of the grounding conductor 21, and extends in the thickness direction of the grounding conductor 21 through the notch 30 of the grounding conductor 21 and the notch 28 of the substrate 20. Further, the material 50 covers the surface (upper surface) of the region near the notch 28 of the ground conductor 21 (regions 25 and 26 shown in FIG. 2) and the surface (lower surface) of the region near the notch 30 of the substrate 20. Covering. With such a configuration, the resonance frequency of the notch antenna configured by the notch 30 is set to the resonance frequency of the notch antenna by the wavelength shortening effect of the material 50 made of a dielectric or magnetic material arranged in the notch 30. The length of the notch 30 can be shortened while maintaining the same value as (for example, 760 MHz).

As shown in FIGS. 13A and 13B, the electric and magnetic fields around the notch 30 are distributed over a wide range exceeding the thickness of the ground conductor 21. Therefore, by making the material 50 have a thickness larger than the thickness of the ground conductor 21, an electric field or a magnetic field penetrating the material 50 is compared with a case where the material 50 has a thickness equal to or less than the thickness of the ground conductor 21. Is increased, and the wavelength shortening effect of the material 50 is enhanced (that is, the length of the notch 30 can be shortened).

(Fourth Embodiment)
Next, a fourth embodiment of the present invention will be described. FIG. 14 is a plan view of the antenna device according to the fourth embodiment, and FIG. 15 is a perspective view of the antenna device shown in FIG. It should be noted that the points not particularly mentioned in the description of the fourth embodiment are the same as those of the first embodiment.

As shown in FIGS. 14 and 15, the antenna device 6c of the fourth embodiment is arranged near the first antenna element 210 arranged near the lower side 23 of the ground conductor 21 and near the upper side 22 of the ground conductor 21. It has a second antenna element 211 and the like. The first and second antenna elements 210 and 211 have substantially the same operating frequency band (for example, 718 to 890 MHz). The first and second antenna elements 210 and 211 both consist of a low profile inverted L antenna. The feeding point (first feeding point) 212 of the first antenna element 210 is provided on the lower side 23 of the ground conductor 21, and the feeding point (second feeding point) 213 of the second antenna element 211 is grounded. It is provided on the upper side 22 of the conductor 21. The first feeding point 212 and the second feeding point 213 do not necessarily have to be located on the ground conductor 21, and are arranged in the vicinity of the ground conductor 21 so as not to overlap the ground conductor 21 in a plan view. May be good.

In this antenna device 6c, unlike the antenna device 6 of the first embodiment, the ground conductor 21 is not formed with a notch, and instead extends in a direction intersecting the upper side 22 (vertical direction in this example). A strip-shaped conductor 60, which is a separate member from the ground conductor 21 to be used, is provided. The band-shaped conductor 60 has one end (first end) 61 electrically connected to the ground conductor 21 and the other end (second end) 62 which is an open end not connected to the ground conductor 21. The band-shaped conductor 60 is separated from the grounding conductor 21 in a direction away from the surface of the grounding conductor 21 and is arranged so as to face the surface of the grounding conductor 21, and the grounding conductor 21 has a band-shaped region 29 facing the grounding conductor 60. Have. The strip-shaped conductor 60 cooperates with the strip-shaped region 29 to form a non-feeding antenna (non-feeding monopole antenna).

The length from the first end portion 61 to the second end portion 62 of the band-shaped conductor 60 is set to approximately 1/4 of the wavelength corresponding to the representative frequency of the operating frequency band of the antenna elements 210 and 211. As a result, the non-feeding antenna composed of the band-shaped conductor 60 resonates in the operating frequency band. In order to make the length of the band-shaped conductor 60 as small as possible and to make it easier for the non-feeding antenna composed of the band-shaped conductor 60 to resonate in the operating frequency band of the antenna elements 210 and 111, the length of the band-shaped conductor 60 is set to the operating frequency. It is preferable that the wavelength corresponding to the representative frequency of the band is approximately 1/4, but if space can be secured, the length of the band-shaped conductor 60 may be set to approximately 1/2 of the wavelength corresponding to the representative frequency of the operating frequency band. It may be the length of.

Further, at least a part of the band-shaped conductor 60 (and the band-shaped region 29 of the ground conductor 21 facing the band-shaped conductor 60) is set to a representative frequency of the operating frequency band from the second feeding point 213 or the open end 211a of the second antenna element 211. It is located at a distance of less than approximately 1/4 of the corresponding wavelength (in this example, equal to the length of the strip conductor 60).

Further, at the first end portion 61 of the strip-shaped conductor 60, a resistance element 240 connected between the strip-shaped conductor 60 and the strip-shaped region 29 of the ground conductor 21 is arranged.

In the antenna device 6c configured as described above, for example, when the second antenna element 211 is fed with a frequency within the operating frequency band, it is arranged so as to face the surface of the ground conductor 21 and the first end portion 61 is the ground conductor 21. A non-feeding antenna composed of a band-shaped conductor 60 electrically connected via a resistance element 240 resonates with the antenna, weakening the electromagnetic coupling between the first and second antenna elements 210 and 211 (that is, isolating the isolation). Work (improve). Further, the resistance element 240 connected between the band-shaped conductor 60 and the ground conductor 21 enhances the mutual impedance between the first and second antenna elements 210 and 211, and is caused by secondary radiation due to the resonance of the non-feeding antenna. Since the electromagnetic coupling is reduced, even if the distance between the first and second antenna elements 210 and 211 is small, the current generated in the first antenna element 211 due to the secondary radiation can be generated by such a resistance element. It can be greatly reduced as compared with the case where 240 is not provided. That is, according to the fourth embodiment, when the first and second antenna elements 210 and 111 having substantially the same operating frequency band are provided and the distance between the first and second antenna elements 210 and 211 is small. However, an antenna device 6c capable of obtaining good antenna-to-antenna isolation with a simple structure is provided.

Further, in the antenna device 6c of the fourth embodiment, the band-shaped conductor 60 is arranged so as to be separated from the band-shaped region 29 of the grounding conductor 21 in the direction away from the surface of the grounding conductor 21 and facing the band-shaped region 29 of the grounding conductor 21. It is possible to realize a non-feeding antenna that resonates in the operating frequency band of the first and second antenna elements 210 and 211 without forming a notch in the ground conductor 21, and to improve the isolation between the antennas.

Further, as described above, since the band-shaped conductor 60 has a length of approximately 1/4 of the wavelength corresponding to the representative frequency of the operating frequency band of the antenna elements 210 and 211, the band-shaped conductor 60 is shortened while being band-shaped. The non-feeding antenna composed of the conductor 60 (or the strip-shaped region 29 of the strip-shaped conductor 60 and the ground conductor 21) facilitates resonance in the operating frequency band of the antenna elements 210 and 211, and improves the isolation between the antenna elements in the operating frequency band. can do.

Further, as described above, at least a part of the band-shaped conductor 60 (and the band-shaped region 29 of the ground conductor 21 facing the band-shaped conductor 60) is in the operating frequency band from the second feeding point 213 or the open end 211a of the second antenna element 211. Since it is located at a distance of less than about 1/4 of the wavelength corresponding to the representative frequency of (in this example, equal to the length of the band-shaped conductor 60), the second antenna element 211 has a frequency within the operating frequency band. When power is supplied, the non-feeding antenna composed of the band-shaped conductor 60 (and the band-shaped region 29 of the ground conductor 21 facing the band-shaped conductor 60) and the second antenna element 211 are strongly electromagnetically coupled to the first antenna element 210. The generated current can be reduced.

Even in the fourth embodiment, the resistance value of the resistance element 240 is composed of the band-shaped conductor 60 measured at the position where the resistance element 240 is connected (in this example, the first end 61 of the band-shaped conductor 60). It is preferable that the input impedance at the resonance frequency of the feeding antenna is substantially equal to that of the resistance element 240 in order to surely obtain the isolation improving effect. Further, the first and second antenna elements 210 and 211 are arranged in the vicinity of one side (for example, the upper side 22) of the ground conductor 21, and the first and second feeding points 212 and 213 are along the one side of the ground conductor. When separated from each other in the direction, the first end portion 61 of the strip-shaped conductor 60 is preferably located between the first feeding point 212 and the second feeding point 213.

As described above, embodiments have been described as examples of the techniques disclosed in this application. However, the technique in the present disclosure is not limited to this, and can be applied to embodiments in which changes, replacements, additions, omissions, etc. have been made. It is also possible to combine the components described in the above embodiments to form a new embodiment.

For example, as shown in FIG. 16, in order to adjust the electrical length of the band-shaped conductor 60 shown in the fourth embodiment (that is, the resonance frequency of the non-feeding antenna composed of the band-shaped conductor 60), in series with the resistance element 240. The inductance element 42 may be connected.

Further, although the notch 30 and the strip-shaped conductor 60 shown in the above embodiment are linear, these notches 30 and the strip-shaped conductor 60 may be bent in an L shape in a plan view or are smoothly bent. You may. Further, it may extend in an inclined direction instead of being perpendicular to the upper side 22. Further, in the first embodiment, the position where the resistance element 40 is arranged is not limited to the open end portion (first end portion 31) of the notch 30, but must be the closed end portion (second end portion 32) of the notch 30. It may be at any position in the direction along the notch 30. However, since the input impedance at the time of resonance of the non-feeding antenna (notch antenna) formed by the notch 30 changes according to the position where the resistance element 40 is arranged, the resistance element 40 of the resistance element 40 changes according to the position where the resistance element 40 is arranged. The appropriate resistance value can change (the closer the notch 30 is to the second end 32, the smaller the appropriate resistance value tends to be). Similarly, in the fourth embodiment, the position where the resistance element 240 is arranged is not limited to the first end portion (the end portion on the upper side 22 side) of the strip-shaped conductor 60, and may be any position in the direction along the strip-shaped conductor 60. .. Further, the ground conductor 21 is not limited to a substantially rectangular conductor as shown in the figure. For example, a flat-plate conductor in which the first feeding point of the first antenna element is arranged and a flat-plate-shaped conductor in which the second feeding point of the second antenna element is arranged are separately provided, and these 2 One conductor may be electrically connected to form one grounding conductor.

The antenna device and the electronic device according to the present invention have an effect that good antenna-to-antenna isolation can be obtained with a simple structure even when the distance between the first and second antenna elements is small, and are substantially the same. It is useful as an antenna device having first and second antenna elements having the operating frequency band of the above and an electronic device equipped with the antenna device.

1 Electronic device 2 Input unit 3 Output unit 4 Memory 5 Controller 6, 6a, 6b, 6c Antenna device 7 Wireless communication unit 8 First feeder line 9 Second feeder line 10, 110, 210 First antenna element 11, 111, 211 Second antenna elements 11a, 211a Open ends 12, 212 First feed points 13, 213 Second feed points 20 Board 21 Ground conductor 22 Upper side 23 Lower sides 25, 26, 29 Band-shaped region 28 Notch 30 Cut Notch (slit)
31 1st end 32 2nd end 33, 34 Side edge 40, 240 Resistance element 41 Capacitive element 42 Inductance element 50 Dielectric or magnetic material 60 Band-shaped conductor 61 1st end 62 2nd end

Claims (13)

Ground conductor and
The first and second feeding points arranged apart from each other on the ground conductor or in the vicinity of the ground conductor,
The first and second antenna elements that are electrically connected to the first and second feeding points and have substantially the same operating frequency band, respectively.
A notch formed on one side of the ground conductor and
A strip-shaped region in the ground conductor extending along the surface of the ground conductor,
A strip-shaped conductor extending along the strip-shaped region apart from the strip-shaped region of the ground conductor and forming a non-feeding antenna that resonates with the strip-shaped region in the operating frequency band.
An antenna device having a strip-shaped region of the ground conductor facing the ground conductor via the notch and a resistance element connecting the strip-shaped conductor. The cutout comprises an antenna device according to claim 1 having a length of approximately 1/4 of the wavelength corresponding to the representative frequency of the operating frequency band. The first and second antenna elements are arranged in the vicinity of the one side of the ground conductor, and the first and second feeding points are separated from each other in the direction along the one side of the ground conductor.
The antenna device according to claim 2, wherein the notch is formed at a position between the first feeding point and the second feeding point on one side. At least one of the first and second antenna elements is arranged in the vicinity of the one side of the ground conductor, has a portion extending along the one side, and has a dimension in a direction perpendicular to the one side of the ground conductor. The antenna device according to claim 1 or 2 , wherein the antenna device is less than approximately 1/10 of the wavelength corresponding to the representative frequency of the operating frequency band. The invention according to any one of claims 1 to 4 , wherein the dielectric material or the magnetic material is arranged in the notch, and the thickness of the dielectric material or the magnetic material is larger than the thickness of the ground conductor. Antenna device. The strip-shaped conductor is a member different from the grounding conductor, is separated from the strip-shaped region of the grounding conductor in a direction away from the surface of the grounding conductor, and is arranged so as to face the strip-shaped region of the grounding conductor. The antenna device according to claim 1. The antenna device according to claim 6 , wherein the band-shaped conductor has a length of approximately 1/4 of a wavelength corresponding to a representative frequency of the operating frequency band. The first and second antenna elements are arranged in the vicinity of one side of the ground conductor, and the first and second feeding points are separated from each other in the direction along the one side of the ground conductor.
The antenna device according to claim 7, wherein one end of the strip-shaped conductor is located between the first feeding point and the second feeding point. The antenna device according to any one of claims 1 to 8, wherein a capacitance element is connected in parallel with the resistance element. The band-shaped region of the ground conductor and at least a part of the band-shaped conductor constituting the non-feeding antenna are set to a representative frequency of the operating frequency band from the second feeding point or the open end of the second antenna element. The antenna device according to any one of claims 1 to 9 , which is located at a distance of less than about 1/4 of the corresponding wavelength. The distance between the second feeding point and the first feeding point, in any one of claims 1 to 1 0 is less than about 1/4 of the wavelength corresponding to the representative frequency of the operating frequency band The antenna device described. The resistance value of the resistance element is approximately equal to the input impedance at the resonance frequency of the non-feeding antenna composed of the band-shaped region of the ground conductor and the band-shaped conductor measured at the position where the resistance element is connected. the antenna device according to any one of claims 1 to 1 1. Said antenna device according to any one of claims 1 to 1 2,
An electronic device including a wireless communication unit that is electrically connected to the first and second feeding points of the antenna device via the first and second feeding lines and communicates with the outside via the antenna device.

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