JP2000068726A - Surface-mounting antenna, antenna device using it and communication equipment using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antenna of small size, wide band, high gain and much of polarized components in the direction of a substrate thickness. SOLUTION: A feeding terminal 11 is formed on the surface of a dielectric substrate 2, a strip-like radiation electrode 12 is formed on one main surface 2a of the substrate 2, a capacitive charging electrode 13 is formed on the other main surface 2b of the substrate 2, the terminal 11 is respectively connected with one end of the electrode 12 and one end of the electrode 13, the other end of the electrode 12 is connected with the other end of the electrode 13 and the electrode 13 is divided into one end side and the other end side through a gap to constitute a surface-mounting antenna 10. Thus, the antenna 10 is such that size is small, band is wide, gain is high, the deterioration of receiving sensitivity depending on the direction of an antenna is reduced, a resonance frequency can be set in a wide range and frequency adjustment is easy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface-mounted antenna, an antenna device using the same, and a communication device using the same, particularly a surface-mounted antenna used for a mobile communication device and the like, and an antenna device using the same. And a communication device using the same.

[0002]

2. Description of the Related Art In recent years, as mobile communication devices, especially mobile phones such as PHSs, have been improved in performance, antennas mounted thereon have been required to have higher performance such as wider band and lighter weight. It is becoming.

FIG. 22 shows a conventional surface mount antenna whose basic configuration is disclosed in Japanese Patent Application Laid-Open No. H10-17139. In FIG. 22, a surface-mounted antenna 1 has a rectangular parallelepiped base 2 made of a dielectric such as ceramics or resin, which is one of insulators.
Are formed by forming several electrodes on the surface. First, a strip-shaped radiation electrode 3 is formed on one main surface 2 a of the base 2. One end of the radiation electrode 3 forms an open end 3a, and the other end is connected to a first ground terminal 4 formed from the end surface 2c of the base 2 to the other main surface 2b. A feed electrode 5 is formed on one main surface 2a of the base 2 adjacent to the radiation electrode 3, and one end of the feed electrode 5 is
Is connected to the power supply terminal 6 formed from the end face 2c to the other main face 2b. Similarly, one main surface 2a of the base 2
A ground electrode 7 close to the open end 3a of the radiation electrode 3.
Is formed, and one end of the ground electrode 7 is connected to the end face 2 c of the base 2.
To the other main surface 2b. Here, the three electrodes of the first and second ground terminals 4 and 8 and the power supply terminal 6 serve as ground electrodes on the mounting substrate side when the surface-mount antenna 1 is mounted on a mounting substrate (not shown). Since the electrode is connected to the power supply line by soldering or the like, it is referred to as a terminal to distinguish it from other electrodes.

When a high-frequency signal is input to the feed terminal 6 in the surface-mounted antenna 1 configured as described above,
A high-frequency signal is transmitted to the radiation electrode 3 via a capacitance formed between the power supply electrode 5 and the open end 3a of the radiation electrode 3. The radiating electrode 3 resonates with the inductance component of the radiating electrode 3 itself and the capacitance formed between the open end 3a and the ground electrode 7, and a part of the energy of the resonance is radiated as radio waves into space. Function as an antenna.
Conversely, the radio wave incident on the surface-mount type antenna 1 resonates at the radiation electrode 3, and the energy is transmitted through the capacitance formed between the open end 3 a of the radiation electrode 3 and the power supply electrode 5. 5 and output from the power supply terminal 6.

[0005]

The surface mount antenna 1 shown in FIG. 22 has a narrow frequency bandwidth, and requires a plurality of surface mount antennas to cover distant frequency bands. To be connected, which causes a problem that an occupied area of the antenna is increased and a gain is deteriorated. Also,
In the surface mount antenna 1, there is a problem that the polarization component in the thickness direction of the base is small, and there is a null point where the gain is small in the thickness direction, and the incoming sensitivity is reduced depending on the direction of the antenna.

Accordingly, an object of the present invention is to provide a small-sized, wide-band, high-gain, surface-mounted antenna having a large polarization component in the thickness direction of a substrate, an antenna device using the antenna, and a communication device using the same. With the goal.

[0007]

In order to solve the above-mentioned problems, a surface mount antenna according to the present invention comprises a base made of an insulator having one main surface, the other main surface and a plurality of end surfaces;
A power supply terminal formed on the surface of the base, a strip-shaped radiation electrode formed mainly on one main surface of the base,
A capacitor loading electrode formed mainly on the other main surface of the base so as to partially face the radiation electrode, wherein the power supply terminal is connected to one end of the radiation electrode and one end of the capacitance loading electrode, respectively; The other end of the radiation electrode is connected to the other end of the capacitive loading electrode, and the capacitive loading electrode is divided into one end side and the other end side via a gap.

Further, a surface mount antenna according to the present invention is characterized in that a load terminal is formed on the surface of the base, connected to the power supply terminal.

Further, a surface mount antenna according to the present invention comprises: a base made of an insulator having one main surface, the other main surface and a plurality of end surfaces; a power supply terminal and a load terminal formed on the surface of the base; A strip-shaped radiation electrode formed mainly on one main surface of the base, and a capacitive loading electrode formed mainly on the other main surface of the base so as to partially face the radiation electrode. One end of a radiation electrode is connected, the load terminal is connected to one end of the capacitive loading electrode, the other end of the radiation electrode is connected to the other end of the capacitive loading electrode, and the capacitive loading electrode is connected to one end via a gap. It is characterized by being divided into a side and the other end.

[0010] Further, a surface mount antenna according to the present invention comprises a base made of an insulator having one main surface, the other main surface and a plurality of end surfaces; a power supply terminal and a load terminal formed on the surface of the base; A strip-shaped radiation electrode formed mainly on one main surface of the base, and a capacitive loading electrode formed mainly on the other main surface of the base so as to partially face the radiation electrode. The load terminal is connected to one end of a capacitive loading electrode, the load terminal is connected to one end of the radiation electrode, the other end of the radiation electrode is connected to the other end of the capacitive loading electrode, and the capacitive loading electrode is connected to one end via a gap. It is characterized by being divided into a side and the other end.

Further, the surface mount antenna according to the present invention is characterized in that a hole is provided in the base.

Further, an antenna device according to the present invention includes each of the above-mentioned surface-mounted antennas and a mounting board on which the surface-mounted antenna is mounted.

Further, in the antenna device according to the present invention, the mounting substrate has a ground electrode, and a portion of the substrate of the surface-mount type antenna where the gap of the capacitive loading electrode is formed is formed more than other portions of the substrate. It is characterized in that the mounting substrate is arranged away from the ground electrode.

Further, a communication device according to the present invention is characterized by using the above antenna device.

With this configuration, according to the present invention, a surface-mounted antenna having a small size, a wide band, a high gain, and a large polarization component in the thickness direction of the substrate, an antenna device using the antenna, and The communication device used can be provided.

[0016]

FIG. 1 shows an embodiment of a surface mount antenna according to the present invention. In FIG. 1, the same or equivalent parts as those in FIG.

In FIG. 1, a surface mount antenna 10
Is formed by forming several electrodes on the surface of a rectangular parallelepiped base 2 made of a dielectric such as ceramics or resin, which is one of the insulators. First, the power supply terminal 11 is
The strip-shaped radiation electrode 12 is formed in a meandering shape from one main surface 2a of the base 2 to the end surface 2f, and the capacitive loading electrode 13 is formed on the other main surface 2b of the base 2.
Is formed to face a part of the radiation electrode 12. The power supply terminal 11 is connected to one end 12a of the radiation electrode 12 and one end 13a of the capacitance loading electrode 13, and the other end 12b of the radiation electrode 12 is connected to the other end 13a of the capacitance loading electrode 13.
b. The capacitance-loaded electrode 13 is almost equally divided into an electrode 13x on one end 13a and an electrode 13y on the other end 13b via a gap 13g.

Here, the power supply terminal 11 is an electrode which is connected to a power supply line on the mounting substrate side by soldering when the surface mount antenna 10 is mounted on a mounting substrate (not shown). , And the other electrodes are referred to as terminals, and the electrodes connected to the mounting substrate are referred to as terminals in the following description.

FIG. 2 shows an equivalent configuration of the surface mount antenna 10 shown in FIG. As shown in FIG. 2, the surface mount antenna 10 has a radiation electrode 12 and a capacitance loading electrode 13 connected in a loop shape, and a feed terminal 11 is connected to one of the connection portions.
Are connected. Then, the capacitance loading electrode 13
Is divided into two electrodes 13x and 13y with the capacitance C1 formed at the position of the gap 13g interposed therebetween, and a capacitance C2 is formed between the radiation electrode 12 and the capacitance loading electrode 13 via the base body 2. I have. The term “capacitance of the capacitance loading electrode 13” means that a capacitance C 2 is formed between the radiation electrode 12 and the capacitance loading electrode 13.

Next, FIG. 3 shows an antenna device in which the surface mount antenna 10 shown in FIG. 1 is mounted on a mounting board.
As shown in FIG. 3, in the antenna device 18, the mounting board 15 is provided with a protruding portion 15 x
The ground electrode 16 is formed on the one main surface 15a of the 5 except for the protrusion 15x, and the power supply line 17 is formed insulated from the ground electrode 16. The surface-mount antenna 10 is mounted at the position of the protrusion 15x with the other main surface 2b of the base 2, that is, the surface on which the capacitive loading electrode 13 is formed, facing the mounting substrate 15.
It is connected to the.

FIG. 4 shows an equivalent circuit of the antenna device 18 configured as described above. As shown in FIG. 4, the antenna device 18 has an inductance L1 and a capacitor C1 connected in parallel, one end of which is connected to the power supply terminal 11 and a capacitor C1.
x, and the other end is grounded through a resistor R1 and a capacitor Cy in series. Further, a capacitance C2 formed between the radiation electrode 12 and the capacitance loading electrode 13 is connected between the inductance L1 and the capacitance C1. Here, the capacitance Cx is the power supply terminal 1 of the surface mount antenna 10.
1 is the capacitance formed between the ground electrode 16 of the mounting substrate 15, and the capacitance Cy is the capacitance formed between the other end of the radiation electrode 12 of the surface mount antenna 10 and the ground electrode 16 of the mounting substrate 15. And the resistor R1 is the surface mount antenna 1
0 represents the sum of the loss and the radiation resistance at each electrode. The antenna device 18 resonates mainly at a frequency determined by the inductance L1 and the capacitances C1, C2, and Cy, and operates as an antenna.

In the surface-mounted antenna 10 and the antenna device 18 configured as described above, the miniaturization is realized by forming the radiation electrode 12 and the capacitance loading electrode 13 on the dielectric substrate 2 of the surface-mounted antenna 10. can do. Moreover, by forming the capacitance loading electrode 13 so as to face the radiation electrode 12, further downsizing can be achieved.

Further, since the other end 12b of the radiation electrode 12 of the surface mount antenna 10 is connected to the other end 13b of the capacitance loading electrode 13 formed on the other main surface 2b of the base 2,
Since it is formed so as to extend from one main surface 2a of the base 2 to the end surface 2f, including the meandering portion, the polarization component not only in the longitudinal direction of the base 2 but also in the thickness direction of the base 2 increases. This eliminates a null point where the gain is reduced in the thickness direction of the base 2, makes it easier to receive cross polarized waves (in this case, polarized waves in a direction orthogonal to the polarized waves in the longitudinal direction of the base 2), The problem that the incoming sensitivity is reduced depending on the direction can be improved.

The main part of the radiation electrode 12 of the surface-mounted antenna 10 is formed on one main surface 2a of the base 2, and via the base 2 and the capacitive loading electrode 13 formed on the other main surface 2b of the base 2. Since they are separated from each other, the concentration of the electric field between the radiation electrode 12 and the capacitive loading electrode 13 can be prevented, and the Q of the surface-mounted antenna 10 can be reduced. And high gain can be achieved.

FIG. 5 is a graph showing the reflection loss of the surface-mounted antenna 10 shown in FIG. 1 in comparison with the reflection loss of the conventional surface-mounted antenna 1 shown in FIG. In FIG. 5, S1 indicates the reflection loss of the surface-mount antenna 10, and S2 indicates the reflection loss of the surface-mount antenna 1. BW1 represents a bandwidth where the reflection loss of the surface-mount antenna 10 is −6 dB or less, and BW2 represents a bandwidth where the reflection loss of the surface-mount antenna 1 is −6 dB or less.
As is clear from FIG. 5, the bandwidth BW1 of the surface-mount antenna 10 is about four times the bandwidth BW2 of the surface-mount antenna 1, and it can be seen that the bandwidth can be significantly increased. As a result, in the surface-mounted antenna 10 and the antenna device 18, an extremely wide band antenna can be provided, and two separate frequency bands can be covered by one antenna without a frequency switching circuit.

Further, in the surface-mounted antenna 10 and the antenna device 18, the interval between the gaps 13g for dividing the capacitive loading electrode 13 into two and the length of the portion facing each other via the gap 13g are reduced by some method. By performing such adjustment, frequency adjustment can be easily performed.

Also, by changing the meander number (the number of bends) of the radiation electrode 12 of the surface-mount type antenna 10, the interval of the gap 13g of the capacitance loading electrode 13, the permittivity of the base 2, etc., the resonance frequency can be widened. It can be set, and the surface mount antenna 10 and the antenna device 18 can be used in a wide range of applications.

To change the capacitance between the power supply terminal 11 and the ground electrode on the mounting board, the shape of the power supply terminal 11 is adjusted, or another electrode is added to the power supply terminal 11. A matching circuit for the surface mount antenna 10 can be formed on the base 2. Therefore, it is not necessary to provide a matching circuit outside the surface mount antenna 10, for example, on a mounting substrate, and the space occupied by the entire antenna device including the matching circuit can be reduced, and the cost of the antenna device can be reduced.

The surface mount antenna 1 shown in FIG.
In the case of 0, the capacitive loading electrode 13 is almost equally divided into the one end 13a side and the multi-end 13b side, but the division ratio of the capacitive loading electrode may be unequal.

FIG. 6 shows another embodiment of the surface mount antenna of the present invention. 6, the same or equivalent parts as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 6, the surface mount type antenna 20
Is different from the surface mount antenna 10 shown in FIG. 1 only in that a load terminal 21 is formed from the end face 2e of the base 2 to the other main face 2b by being connected to the power supply terminal 11.

The surface-mounted antenna 2 thus formed
FIG. 7 shows an embodiment of an antenna device using the load terminal 21 of No. 0. 7, the same or equivalent parts as those in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted.

In the antenna device 22 shown in FIG.
The load terminal 21 of the surface mount antenna 20 is mounted on the mounting board 1
5 is connected to a frequency adjusting electrode 23 formed insulated from the ground electrode 16 and the feed line 17 on one main surface 15a.

By configuring the antenna device 22 in this manner, the frequency adjustment electrode 23 has a capacitance between the ground electrode 16 and other electrodes, and the capacitance is connected in parallel to the power supply terminal 11 of the surface mount antenna 20. Will be added. Therefore, the resonance frequency of the antenna device 22 can be easily finely adjusted by shaving the electrode 23 for frequency adjustment by any method or attaching another conductor to the electrode 23 for frequency adjustment.

Next, another embodiment of the antenna device using the load terminal 21 of the surface mount antenna 20 is shown in FIG. 8, the same or equivalent parts as those in FIG. 7 are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 8, the load terminal 21 of the surface mount antenna 20 is connected to one end of the strip-shaped line electrode 25 formed by connecting one end to the ground electrode 16 on one main surface 15a of the mounting board 15. It is connected. Here, another ground electrode (not shown) is formed at a position facing the line electrode 25 on the other main surface of the mounting substrate 15, and the line electrode 25 operates as a microstrip line having one end as a ground end. I do.

By configuring the antenna device 24 in this manner, the line electrode 25 operates as a part of the radiation electrode 12 of the surface mount antenna 20, so that the electric volume of the surface mount antenna 20 can be increased. As a result, the bandwidth and gain of the antenna device 24 can be improved. Changing the length of the line electrode 25 corresponds to changing the length of the radiation electrode 12 of the surface mount antenna 20, and easily sets the resonance frequency of the antenna device 24 to an appropriate value in a wide frequency range. be able to.

In the antenna device 24, one end of the line electrode 25 is connected to the ground electrode 16, but one end of the line electrode 25 may be formed as an open end. Is played.

Next, still another embodiment of the antenna device using the load terminal 21 of the surface mount antenna 20 is shown in FIG. In FIG. 9, the same or equivalent parts as those in FIG. 7 are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 9, the load terminal 21 of the surface mount antenna 20 is connected to a frequency switching circuit 27 formed on one main surface 15a of the mounting board 15. The frequency switching circuit 27 is composed of, for example, a diode serving as a switching element, an inductor, and a capacitor. The frequency switching circuit 27 supplies the magnitude of the impedance of a load connected between the load terminal 21 and the ground electrode 16 to the diode from the outside. It can be electrically changed by such means.

By configuring the antenna device 26 in this manner, the impedance of the load connected to the load terminal 21 can be electrically switched, whereby the resonance frequency of the antenna device 26 can be switched and a wider range can be obtained. It can correspond to a frequency band.

FIG. 10 shows still another embodiment of the surface mount antenna of the present invention. 10, the same or equivalent parts as those in FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted.

Referring to FIG. 10, a surface mount type antenna 40 is shown.
The capacitor loading electrode 41 is formed on the other main surface 2 b of the base 2 so as to face a part of the radiation electrode 12, and the load terminal 42 is formed on the end surface 2 e of the base 2. Of these, load terminal 4
2 is connected to one end 41a of the capacitance loading electrode 41, and the other end 12b of the radiation electrode 12 is connected to the other end 41b of the capacitance loading electrode 41. The capacitance-loaded electrode 41 is connected to the electrode 41x on one end 41a and the other end 4 via a gap 41g.
The electrode 41y on the 1b side is divided unevenly. That is, the surface-mounted antenna 40 differs from the surface-mounted antenna 10 shown in FIG. 1 in that one end 41 a of the capacitive loading electrode 41 is connected to the load terminal 42 instead of being connected to the power supply terminal 11. Is a point.

FIG. 11 shows an equivalent configuration of the surface mount antenna 40 shown in FIG. As shown in FIG.
The surface-mounted antenna 40 has a radiation electrode 12 and a capacitance loading electrode 41 connected to each other at the other end to form a U-shape. One end of the radiation electrode 12 is connected to the power supply terminal 11 and one end of the capacitance loading electrode 41 is connected to the load terminal. 42. The capacitance loading electrode 41 is divided into two electrodes 41x and 41y with a capacitance C3 formed at the position of the gap 41g interposed therebetween, and between the radiation electrode 12 and the capacitance loading electrode 41 via the base 2 The capacitance C4 is formed.

Next, FIG. 12 shows an antenna device in which the surface mount antenna 40 shown in FIG. 10 is mounted on a mounting board. 12, parts that are the same as or equivalent to those in FIG. 7 are given the same reference numerals, and descriptions thereof will be omitted. As shown in FIG. 12, in the antenna device 43, the surface-mounted antenna 40 is provided with the other main surface 2 b of the base 2,
The power supply terminal 11 is connected to the power supply line 17, and the load terminal 42 is directly connected to the ground electrode 16, that is, a load having an impedance of 0Ω, and grounded.

FIG. 13 shows an equivalent circuit of the antenna device 43 configured as described above. 13, the same or equivalent parts as those in FIG. 4 are denoted by the same reference numerals, and the description thereof will be omitted. As shown in FIG. 13, the antenna device 43 includes:
The inductance L1, the resistance R1, and the capacitance C3 are connected in series, one end of the inductance L1 is connected to the power supply terminal 11 and grounded via the capacitance Cx, one end of the capacitance C3 is grounded, and the connection between the inductance L1 and the resistance R1 is connected. It is configured to be grounded via a capacitor Cy. Further, between the inductance L1 and the capacitance C3, a capacitance C4 formed between the radiation electrode 12 and the capacitance loading electrode 41 is connected. Then, the antenna device 43 resonates mainly at a frequency determined by the inductance L1 and the capacitances C3 and C4, and operates as an antenna.

In the surface-mounted antenna 40 and the antenna device 43 configured as described above, the surface-mounted antenna 10 shown in FIG. 1 and the antenna device 43 shown in FIG. The same operation and effect as those of the antenna device 18 shown in FIG.

In the antenna device 43 shown in FIG. 12, the load terminal 42 of the surface mount antenna 40 is connected to the ground electrode 16 of the mounting board 15 and grounded. The configuration is not limited to the configuration in which the terminal 42 is connected to the ground electrode 16, and the load terminal 42 is used as in the antenna devices 22, 24, and 26 shown in FIGS. 7 to 9 using the surface-mounted antenna 20 shown in FIG. The frequency adjustment electrode or strip-shaped line electrode,
It may be configured to be connected to the frequency switching circuit, and has the same operation and effect as the antenna devices 22, 24, and 26.

FIG. 14 shows still another embodiment of the surface mount antenna of the present invention. 14, the same or equivalent parts as those in FIG. 10 are denoted by the same reference numerals, and the description thereof will be omitted.

Referring to FIG. 14, a surface mount antenna 50 is shown.
The power supply terminal 51 is formed on the end face 2 e of the base 2, the load terminal 52 is formed from the end face 2 e to the other main surface 2 b, one end of the capacitance loading electrode 41 is connected to the power supply terminal 51, and one end of the radiation electrode 12 is connected to the power supply terminal 51. Only the point connected to the load terminal 52 is different from the surface mount antenna 40 shown in FIG.

FIG. 15 shows an equivalent configuration of the surface mount antenna 50 shown in FIG. In FIG. 15, FIG.
Parts that are the same as or equivalent to 1 are given the same symbols, and descriptions thereof are omitted. In FIG. 15, as in FIG. 11, the other end of the radiation electrode 12 and the other end of the capacitance loading electrode 41 are connected to the surface-mounted antenna 50. However, one end of the capacitance loading electrode 41 is connected to the power supply terminal 51 and the radiation electrode 12
Is connected to the load terminal 52, that is, the roles of the power supply terminal and the load terminal are switched, which is different from the equivalent configuration of the surface mount antenna 40 shown in FIG.

Next, FIG. 16 shows an antenna device in which the surface mount antenna 50 shown in FIG. 14 is mounted on a mounting board. In FIG. 16, the same or equivalent parts as those in FIG. 12 are denoted by the same reference numerals, and description thereof will be omitted. As shown in FIG. 16, in the antenna device 53, the surface-mounted antenna 50 has the other main surface 2 b of the base 2, that is, the capacitance loading electrode 41, at the position of the protrusion 15 x provided on the mounting board 15.
The power supply terminal 51 is connected to the power supply line 17, and the load terminal 52 is directly connected to the ground electrode 16, that is, a load having an impedance of 0Ω, and is grounded.

FIG. 17 shows an equivalent circuit of the antenna device 53 thus configured. 17, parts that are the same as or equivalent to those in FIG. 13 are given the same reference numerals, and descriptions thereof will be omitted. As shown in FIG.
13 differs from the equivalent circuit of the antenna device 43 shown in FIG. 13 in that one end of the inductance L1 is grounded, one end of the capacitance C3 is connected to the feed terminal 51, and grounded via the capacitance Cx. is there.

The surface-mounted antenna 50 and the antenna device 53 configured as above are different from the surface-mounted antenna 40 and the antenna device 43 in that the power is supplied to the radiation electrode 12 via the capacitor C3. The same effects as those of the surface-mount antenna 10 and the antenna device 18 shown in FIG. 1 can be obtained, such as miniaturization, wide band, and high gain.

In the antenna device 53 shown in FIG. 16, the load terminal 52 of the surface mount antenna 50 is connected to the ground electrode 16 of the mounting board 15 and grounded. The configuration is not limited to the configuration in which the terminal 52 is connected to the ground electrode 16, and the load terminal 52 is used as in the antenna devices 22, 24, and 26 shown in FIGS. 7 to 9 using the surface mount antenna 20 shown in FIG. The frequency adjustment electrode or strip-shaped line electrode,
It may be configured to be connected to the frequency switching circuit, and has the same operation and effect as the antenna devices 22, 24, and 26.

FIG. 18 shows still another embodiment of the surface mount antenna of the present invention. 18, the same or equivalent parts as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

Referring to FIG. 18, the surface mount antenna 60
1 is different from the surface mount antenna 10 shown in FIG. 1 only in that two holes 61 are provided penetrating from the end face 2 c to the end face 2 d of the base 2.

As described above, by providing the holes 61 in the base 2 of the surface mount antenna 60, a part of the dielectric between the radiation electrode 12 and the capacitance loading electrode 13 is removed,
The substantial dielectric constant decreases. The decrease in the dielectric constant can reduce the concentration of the electric field between the radiation electrode 12 and the capacitance-loaded electrode 13, whereby the electric field easily leaks to the outside of the base 2, and the surface mount antenna 60 There is a merit that the bandwidth is increased and the gain is improved. Further, by providing the holes 61, the base 2
, That is, the weight of the surface mount antenna 60 can be reduced.

In FIG. 18, two holes are provided in the base of the surface-mounted antenna 10 shown in FIG. 1 to form the surface-mounted antenna 60. However, FIGS.
The surface mount antennas 20, 40, and 50 shown in FIG. 4 may be provided with holes, and have the same effect.

The number of holes is not limited to two, and the same effect can be obtained if the number is one or more.

FIG. 19 shows still another embodiment of the surface mount antenna of the present invention. In FIG. 19, the same or equivalent parts as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

Referring to FIG. 19, the surface mount antenna 70
One end 71a of the capacitor loading electrode 71 is formed so as to extend from the other main surface 2b of the base 2 to the end surface 2e, one end 71a of the capacitance loading electrode 71 is connected to the power supply terminal 11, and the other end 71b is connected to the radiation electrode 12 Is connected to the other end 12b. Further, on the end face 2e, the capacitive loading electrode 71 is unequally divided into an electrode 71x on one end 71a and an electrode 71y on the other end 71b via a gap 71g.

Next, FIG. 20 shows an antenna device in which the surface mount antenna 70 shown in FIG. 19 is mounted on a mounting board. 20, parts that are the same as or equivalent to those in FIG. 3 are given the same reference numerals, and descriptions thereof will be omitted.

In the antenna device 72 shown in FIG. 20, the surface mounting type antenna 70 is configured such that the other main surface 2 b of the base 2, that is, the surface on which the capacitance loading electrode 71 is formed, is mounted on the mounting substrate 15 in the projecting portion 15 x of the mounting substrate 15. The portion where the gap 71g of the capacitive loading electrode 71 is formed is arranged farther from the ground electrode 16 of the mounting board 15 than other portions of the base 2. The power supply line 17 is connected to the power supply terminal 11 of the surface mount antenna 70.

By configuring the antenna device 72 in this manner, the position of the gap 71g of the capacitance loading electrode 71 in the surface-mounted antenna 70 moves away from the ground electrode 16 of the mounting board 15, so that the gap 71g and the ground electrode 16 The concentration of the electric field between the antenna device 72 and the antenna device 72 can be reduced, and the deterioration of the gain inherent in the surface mount antenna 70 as the antenna device 72 can be prevented.

In FIG. 20, a gap 71g of the capacitance loading electrode 71 is
Is formed on the mounting substrate 1 more than the other portions of the base 2.
The antenna device 72 was configured to be separated from the ground electrode 16 of FIG. 5, but the antenna device was configured by using the surface mount antennas 20, 40, 50, and 60 illustrated in FIGS. The same operation and effect can be obtained.

In each of the above embodiments of the surface mount antenna, the radiation electrode is formed in a meandering shape. However, the radiation electrode is not necessarily limited to a meandering shape. Any shape is acceptable.

In each of the above embodiments of the surface mount antenna, the base is formed using a dielectric material.
The base may be formed by using a magnetic material which is also an insulator.

In each of the above embodiments of the antenna device, the other main surface of the base, that is, the surface on which the capacitance-loaded electrodes are formed is mounted facing the mounting substrate. The surface on which the electrodes are formed may be mounted facing the mounting substrate, and the same effect can be obtained.

FIG. 21 shows an embodiment of a communication device equipped with the antenna device 18 of the present invention. In FIG. 21, FIG.
The same reference numerals are given to the same or equivalent parts, and the description thereof is omitted. In FIG. 21, a communication device 80 includes a housing 81.
The mounting substrate 15 is provided in the inside, and a ground electrode 16 and a power supply line 17 are formed on the mounting substrate 15. There is a region where the ground electrode 16 is not formed at a corner portion of the mounting substrate 15, and the surface mount antenna 10 of the present invention is mounted on this region to constitute the antenna device 18. A power supply terminal (not shown) of the surface mount antenna 10 is connected to a power supply line 17 of the mounting board 15. Further, the power supply line 17 is connected via a switching circuit 82 formed on the mounting board 15 to a transmitting circuit 83 and a receiving circuit 84 also formed on the mounting board 15.

As described above, by using the antenna device 18 of the present invention, the communication device 80 can be reduced in size, the gain and the bandwidth can be improved, the null point at which the gain decreases can be reduced, and the direction of the communication device 80 can be reduced. It is possible to improve the decrease in the incoming call sensitivity.

In the embodiment shown in FIG. 21, the communication device 80 is constituted by using the antenna device 18 shown in FIG. 3, but shown in FIGS. 7, 8, 9, 12, 16 and 20. Even if a communication device is configured using the antenna devices 22, 24, 26, 43, 53, 72, the same operation and effect can be obtained.

[0073]

According to the surface mount antenna of the present invention,
A power supply terminal is formed on a surface of a base made of an insulator, and a strip-shaped radiation electrode is formed mainly on one main surface of the base,
A capacitive loading electrode is formed on the other principal surface of the base, partially facing the radiating electrode, and a power supply terminal is connected to one end of the radiating electrode and one end of the capacitive loading electrode, respectively. The other end is connected, and the capacitance loading electrode is divided into one end and the other end through a gap, so that it is small, wide band, high in gain, and the receiving sensitivity is reduced depending on the direction of the antenna. The problem can be improved, the resonance frequency can be set in a wide range, and the frequency can be easily adjusted.

Further, by forming the load terminal by connecting to the power supply terminal, the load connected to the load terminal
The frequency can be easily adjusted, the gain can be improved, and the resonance frequency can be changed or switched.

According to the surface mount antenna of the present invention, the power supply terminal is connected to one end of the radiation electrode and the load terminal is connected to one end of the capacitance loading electrode. Also, by connecting the load terminal to one end of the radiation electrode, it is possible to improve the problem of small size, wide band, high gain, and a decrease in incoming sensitivity depending on the direction of the antenna. The resonance frequency can be set in a wide range, and the frequency can be easily adjusted. Then, by forming the load terminal by connecting to the power supply terminal, the frequency adjustment can be easily performed, the gain can be improved, and the resonance frequency can be changed or switched depending on the load connected to the load terminal. .

Further, according to the surface mount antenna of the present invention, by providing holes in the base, the bandwidth can be widened,
The gain can be improved. Further, the weight can be reduced.

Further, according to the antenna device of the present invention, by using the above-mentioned surface-mounted antenna, it is possible to obtain the same effects as those of the surface-mounted antenna. Further, by mounting the gap-formed portion of the capacitance loading electrode of the surface mount antenna away from the ground electrode of the mounting board, as an antenna device,
It is possible to prevent deterioration of the gain inherent in the surface mount antenna.

Further, according to the communication device of the present invention, by using the antenna device of the present invention, the communication device can be downsized, the gain and the bandwidth can be improved, and the null point at which the gain becomes small can be reduced. It is possible to improve the decrease in the incoming call sensitivity due to the direction of the machine.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a surface mount antenna according to the present invention.

FIG. 2 is a diagram showing an equivalent configuration of the surface mount antenna of FIG. 1;

FIG. 3 is a perspective view showing an embodiment of the antenna device of the present invention.

FIG. 4 is a diagram showing an equivalent circuit of the antenna device of FIG. 3;

FIG. 5 is a graph showing a bandwidth of the surface mount antenna of FIG. 1;

FIG. 6 is a perspective view showing another embodiment of the surface mount antenna according to the present invention.

FIG. 7 is a perspective view showing another embodiment of the antenna device of the present invention.

FIG. 8 is a perspective view showing still another embodiment of the antenna device of the present invention.

FIG. 9 is a perspective view showing still another embodiment of the antenna device of the present invention.

FIG. 10 is a perspective view showing still another embodiment of the surface mount antenna according to the present invention.

11 is a diagram illustrating an equivalent configuration of the surface mount antenna of FIG. 10;

FIG. 12 is a perspective view showing still another embodiment of the antenna device of the present invention.

13 is a diagram showing an equivalent circuit of the antenna device of FIG.

FIG. 14 is a perspective view showing still another embodiment of the surface mount antenna according to the present invention.

FIG. 15 is a diagram showing an equivalent configuration of the surface mount antenna of FIG. 14;

FIG. 16 is a perspective view showing still another embodiment of the antenna device of the present invention.

17 is a diagram showing an equivalent circuit of the antenna device of FIG.

FIG. 18 is a perspective view showing still another embodiment of the surface mount antenna according to the present invention.

FIG. 19 is a perspective view showing still another embodiment of the surface mount antenna according to the present invention.

FIG. 20 is a perspective view showing still another embodiment of the antenna device of the present invention.

FIG. 21 is a perspective view of a communication device according to an embodiment of the present invention.

FIG. 22 is a perspective view showing a conventional surface mount antenna.

[Explanation of symbols]

2 Base 2a One main surface 2b Other main surface 2c, 2d, 2e, 2f End surface 10, 20, 40, 50, 60, 70 Surface mounted antenna 11, 51 Feed terminal 12 Radiation electrode 12a One end of the radiation electrode 12b ... The other end of the radiation electrode 13, 41, 71 ... Capacity loading electrode 13a, 41a, 71a ... One end of the capacitance loading electrode 13b, 41b, 71b ... The other end of the capacitance loading electrode 13x, 13y, 41x, 41y , 71x, 71y ... electrodes 13g, 41g, 71g ... gap 15 ... mounting board 15a ... one main surface of the mounting board 15x ... projecting part of the mounting board 16 ... ground electrode 17 ... power supply lines 18, 22, 24, 26, 43, 53, 72: Antenna device 21, 42, 52: Load terminal 23: Frequency adjusting electrode 25: Line electrode 27: Frequency switching circuit 61: Void 80: Communication device 1, C2, C3, C4, Cx, Cy ... capacity R1 ... resistance

Claims (8)

[Claims] 1. A base made of an insulator having one main surface, another main surface and a plurality of end surfaces, a power supply terminal formed on a surface of the base, and a strip formed mainly on one main surface of the base. And a capacitive loading electrode formed mainly on the other main surface of the base so as to partially face the radiation electrode, wherein the power supply terminal is connected to one end of the radiation electrode and one end of the capacitive loading electrode. Surface-mounted type, wherein the other end of the radiation electrode is connected to the other end of the capacitive loading electrode, and the capacitive loading electrode is divided into one end and the other end via a gap. antenna. 2. The surface-mounted antenna according to claim 1, wherein a load terminal is formed on a surface of the base, the load terminal being connected to the power supply terminal. 3. A base made of an insulator having one main surface, the other main surface, and a plurality of end surfaces, a power supply terminal and a load terminal formed on the surface of the base, and a power supply terminal and a load terminal formed mainly on one main surface of the base. A radiation electrode in the form of a strip, and a capacitive loading electrode formed mainly on the other main surface of the base so as to partially face the radiation electrode, wherein the power supply terminal is connected to one end of the radiation electrode, The load terminal is connected to one end of the capacitive loading electrode, the other end of the radiation electrode is connected to the other end of the capacitive loading electrode, and the capacitive loading electrode is divided into one end and the other end via a gap. A surface-mounted antenna. 4. A base made of an insulator having one main surface, the other main surface, and a plurality of end surfaces, a power supply terminal and a load terminal formed on the surface of the base, and a power supply terminal and a load terminal formed mainly on one main surface of the base. A radiation electrode in the form of a strip, and a capacitive loading electrode formed mainly on the other main surface of the base so as to partially face the radiation electrode, wherein the power supply terminal is connected to one end of the capacitive loading electrode, The load terminal is connected to one end of the radiation electrode, the other end of the radiation electrode is connected to the other end of the capacitive loading electrode, and the capacitive loading electrode is divided into one end and the other end via a gap. A surface-mounted antenna. 5. The surface mount antenna according to claim 1, wherein holes are provided in the base. 6. An antenna device comprising: the surface-mounted antenna according to claim 1; and a mounting board on which the surface-mounted antenna is mounted. 7. The mounting substrate has a ground electrode, and a portion of the substrate of the surface-mount type antenna where a gap of the capacitive loading electrode is formed is formed more than the other portions of the substrate. The antenna device according to claim 6, wherein the antenna device is arranged away from the antenna device. 8. A communication device using the antenna device according to claim 6.