JP3114479B2 - Surface mount antenna - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mounted on a substrate via one side surface of a dielectric substrate and supplied with power to a radiation electrode formed on an inner peripheral surface of a through hole provided in the dielectric substrate. It relates to a mounting type antenna.

[0002]

2. Description of the Related Art Recently, with the spread of automobile telephones and mobile telephones, there has been a great demand for miniaturization of antennas used for transmitting and receiving high frequency signals.

FIG. 5 shows an embodiment of a communication device such as a mobile phone using an antenna. The antenna 10 is a dielectric-loaded monopole antenna, in which a through-hole 30 is formed in a cylindrical dielectric substrate 20, and a radiation electrode 40 made of, for example, Cu is formed on the inner periphery thereof. A male connector 60 is attached to one end surface of the dielectric base 20 and is connected to a female connector 70 provided on the communication device main body 80 to supply power to the radiation electrode 40 and transmit and receive a high-frequency signal. Is possible.

[0004]

However, in such a communication device, the antenna 10 is connected to the communication device main body 80.
Not only hinders miniaturization, but also causes external forces to act directly on the antenna, causing problems such as reduced mechanical strength, durability, and changes in characteristics. There is.

Further, since transmission and reception of high-frequency signals are performed via the connector, problems such as loss in the connector and changes in the resonance frequency occur.

Further, the use of the connector increases the number of parts, which is not preferable in terms of workability and cost.

Therefore, as shown in FIG. 6, there has been proposed a surface mount antenna which is directly mounted on a substrate without using a connector or the like.

In the surface mount antenna 11, a through hole 33 is formed from one end surface to the other end surface of the columnar dielectric substrate 22, and a radiation electrode 44 is formed on an inner peripheral surface thereof. An end face electrode 99 is formed on one end face of the dielectric substrate 22 and is connected to the radiation electrode 44.

The substrate 100 is housed in a case such as a communication device main body with the surface-mounted antenna 11 mounted thereon, and the surface-mounted antenna 1 is mounted on the main surface on the mounting side.
In addition to a power supply line 140 serving as a power supply unit for supplying power to the power supply 1, a signal processing circuit (not shown) such as a transmission circuit and a reception circuit is formed.

The surface mount antenna 11 is mounted on the substrate 100 via one side surface, and the end face electrode 99 and the power supply line 140 are connected and fixed by, for example, solder, adhesive or the like (not shown). You.

A fixing electrode 88 is formed from the side surface to the bottom surface of the dielectric substrate 22, and corresponds to the fixing conductor 180 formed on the mounting-side main surface of the substrate 100.
Similarly, they are connected and fixed with solder, adhesive or the like (not shown).

Such a surface mount antenna 11 is effective in that no connector is required and that it can be directly surface mounted on a substrate, as compared with a conventional dielectric loaded antenna.

However, the size of the dielectric substrate 22 in the longitudinal direction has not been able to sufficiently satisfy the demand for miniaturization.

The connection between the radiation electrode 44 and the feed line 140 is made via an end face electrode 99 formed on one end face of the dielectric substrate 22. Therefore, the radiation electrode 4
4 is supplied from one end in the longitudinal direction. In order to obtain impedance matching between the radiation electrode 44 and the power supply line 140, the size of the dielectric substrate 22 and the hole diameter of the through hole 33 must be adjusted. By changing the radiation electrode 4
4 need to be changed. That is,
After the size of the surface mount antenna 11 is determined, there is a problem that it is very difficult to match the impedance.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and is capable of being surface-mounted and capable of achieving a sufficient miniaturization, and further having an impedance between a radiation electrode and a power supply line. It is an object of the present invention to provide a surface mount antenna capable of easily matching.

[0016]

According to the present invention, there is provided a columnar dielectric substrate having at least one through hole, mounted on the substrate through one surface of the dielectric substrate, A surface-mounted antenna in which power is supplied to a radiation electrode formed on an inner peripheral surface of the through-hole by a power supply unit provided on the substrate, wherein the dielectric substrate is arranged such that the through-hole extends from a surface of the dielectric substrate. , A power supply electrode formed on an inner peripheral surface of the power supply hole, and a power supply terminal electrode connected to the power supply electrode, wherein the power supply terminal electrode is connected to a power supply unit provided on the substrate. It is characterized by the following.

Further, the columnar dielectric substrate has at least one through hole, is mounted on the substrate through one surface of the dielectric substrate, and is provided on the inner peripheral surface of the through hole by a power supply portion provided on the substrate. Wherein the dielectric substrate is formed on a feed hole reaching the through hole from a surface of the dielectric substrate, and on an inner peripheral surface of the feed hole. A power supply electrode, a power supply terminal electrode connected to the power supply electrode, and an end surface electrode formed on at least one end surface of the dielectric substrate and connected to the radiation electrode;
The power supply terminal electrode may be connected to a power supply unit provided on the substrate.

Further, the power supply hole is formed on a side surface, a top surface, or a bottom surface of the dielectric substrate.

[0019]

According to the present invention, since the radiation electrode formed on the inner peripheral surface of the through hole in the dielectric substrate is supplied with power by the power supply hole formed in the middle thereof, the radiation electrode is formed in the power supply hole. The supplied inductance component of the feed electrode contributes to radiation, and as a result, the length of the radiation electrode can be shortened.

Further, by providing an end face electrode on the end face connected to the radiation electrode, the resonance frequency of the antenna can be lowered by the capacitance component formed between the end face electrodes. In this case, the length of the radiation electrode can be reduced.

Further, by selecting the position of the power supply hole and changing the power supply position with respect to the radiation electrode, the impedance between the radiation electrode and the power supply line can be easily matched.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below in detail with reference to FIGS. The surface mount antenna 1
For example, through holes 3 are formed in the dielectric substrate 2 made of ceramics, polypropylene resin, polybutylene terephthalate resin, polycarbonate resin, or a mixture of ceramics and the resin from the end faces 2e to 2f.
Cu, Ag, Ag-P is applied to the entire inner peripheral surface of the through hole 3 by, for example, plating or applying a conductive paste.
d, a radiation electrode 4 made of Ag-Pt is formed.

The surface-mounted antenna 1 configured as described above generates a high-frequency electromagnetic field when radio-frequency power is supplied to the radiation electrode 4, and transmits a radio wave from the radiation electrode 4. Also, when the radiation electrode 4 receives a radio wave,
Induces high-frequency current and transmits it to the transmission line.

[First Embodiment] FIG. 1 is a perspective view showing a first embodiment of the present invention, and FIG. 2 is a perspective view showing a state in which a surface mount antenna is mounted on a substrate. In the surface mount antenna 1, in addition to the above configuration, a feed hole 5 is formed so as to reach the through hole 3 from the side surface 2 c of the dielectric substrate 2. On the entire inner peripheral surface of the power supply hole 5, for example, Cu, Ag, Ag-
A power supply electrode 6 made of Pd and Ag-Pt is formed and connected to the radiation electrode 4.

The power supply hole 5 in the side surface 2c of the dielectric substrate 2
The power supply terminal electrode 7 is formed in a portion including the circumference of the bottom surface 2b and is connected to the radiation electrode 4 via the power supply electrode 6.

An end face electrode 9 is formed on the end faces 2 e and 2 f of the dielectric substrate 2, and is connected to the radiation electrode 4.
Further, a fixing electrode 8 for fixing to a board to be mounted is formed on a portion extending from the side surface 2c to the bottom surface 2b of the dielectric substrate 2 and a portion extending from the side surface 2d to the bottom surface 2b of the dielectric substrate 2. In the present embodiment, the fixing electrodes 8 are formed at four places in a portion extending from the side surfaces 2c and 2d to the bottom surface 2b. However, according to the required fixing strength and the manufacturing cost, the fixing electrodes 8 are formed. It may be formed only on 2d or only on bottom surface 2b. Also,
The number and shape are also appropriately selected.

In this embodiment, since the power is supplied to the radiation electrode 4 by the power supply hole 5 formed in the middle part in the longitudinal direction, the power supply electrode 6 formed in the power supply hole 5 is supplied to the radiation electrode 4. The inductance component contributes to the radiation, and the length of the radiation electrode 4, that is, the length L of the surface-mount antenna 1 can be reduced as compared with the conventional configuration in which power is supplied from the end of the radiation electrode.

Although the power supply hole 5 is formed on the side surface 2c of the dielectric substrate 2 in the present embodiment, it may be formed on the side surface 2d. In this case, the power supply terminal electrode 7 includes the periphery of the power supply hole 5 on the side surface 2 d of the dielectric substrate 2, and
b.

Next, the mounting state of the surface mount antenna 1 on the substrate will be described. As shown in FIG. 2, a power supply unit 110, a fixing conductor 180, and a ground conductor 190 are formed on one main surface 100a of the mounting substrate 100. The power supply section 110 includes a power supply conductor 170 and a power supply hole 160. The power supply hole 160 is formed to penetrate in the thickness direction of the substrate 100, a conductor is formed on the inner peripheral surface thereof, and the power supply hole 160 is connected to the power supply line 140 formed on the other main surface 100 b of the substrate 100. I have. The number of the power supply holes 160 is not limited to one, and a plurality of power supply holes 160 may be provided as necessary.

The surface mount antenna 1 includes a feed terminal electrode 7, a fixing electrode 8, and an end face electrode 9 formed on the dielectric substrate 2.
Are the power supply conductor 170, the fixing conductor 180, and the ground conductor 1 formed on one main surface 100a of the substrate 100, respectively.
It is placed so as to correspond to 90 and is connected and fixed by, for example, a solder, an adhesive or the like (not shown).

That is, in the surface mount antenna 1, a power supply line 140, a power supply hole 160, a power supply conductor 170, a power supply terminal electrode 7,
Power is supplied to the radiation electrode 4 via the power supply conductor 6.

Further, when matching the impedance between the radiation electrode 4 and the power supply line 140, the position of the power supply to the radiation electrode 4 can be changed by selecting the position of the power supply hole 5. The impedance of the power supply line 140 can be changed. That is, the impedance can be easily matched without changing the size of the surface mount antenna 1.

[Second Embodiment] FIG. 3 is a perspective view showing a second embodiment of the present invention. The same parts as those in the first embodiment or corresponding parts are denoted by the same reference numerals, and detailed description will be omitted. The second embodiment is characterized in the position of forming the power supply hole 5, the shape of the power supply terminal electrode 7, and the position of forming the end face electrodes 9a and 9b, as compared with the first embodiment.

That is, the power supply hole 5 is formed so as to reach the through hole 3 from the upper surface 2 a of the dielectric substrate 2. Power supply hole 5
In the same manner as in the first embodiment, Cu, Ag,
A power supply electrode 6 made of Ag-Pd and Ag-Pt is formed and connected to the radiation electrode 4.

The power supply hole 5 on the upper surface 2a of the dielectric substrate 2
Is formed on a portion extending from the side surface 2 c to the bottom surface 2 b, and is connected to the radiation electrode 4 via the power supply electrode 6.

Here, also in the present embodiment, four fixing electrodes 8 for fixing the surface-mounted antenna 1 to the mounting substrate are formed at four portions from the side surfaces 2c, 2d to the bottom surface 2b of the dielectric substrate 2. Similarly to the first embodiment, it may be formed only on the side surfaces 2c and 2d or only on the bottom surface 2b according to the required fixing strength and the manufacturing cost. Also, the number and shape are appropriately selected.

Also in this embodiment, since the power is supplied to the radiation electrode 4 by the power supply hole 5 formed in the middle part in the longitudinal direction, for the reason described in the first embodiment, In addition, the length of the radiation electrode 4, that is, the length L of the surface-mount antenna 1 can be made shorter than that supplied from the end of the radiation electrode.

Further, end surfaces 2e and 2e of dielectric substrate 2
End electrodes 9a and 9b are formed on f. As a result, a capacitance component is formed between the end face electrodes 9a and 9b, and the resonance frequency of the surface mount antenna 1 decreases. Here, in order to obtain a target resonance frequency (resonance frequency in a state where the end face electrode is not formed), it is necessary to increase the lowered resonance frequency, and as a measure, the length of the radiation electrode 4, that is, Reducing the length L of the surface mount antenna 1 can be mentioned.

That is, by forming the end face electrodes 9a and 9b, the length L can be further shortened as a result as compared with an antenna having no end face electrodes and having the same resonance frequency.

The end electrodes 9a and 9b do not need to be formed on the entire surfaces of the end faces 2e and 2f as shown in FIG. 3, and the positions of the end electrodes 9a and 9b are determined according to the target resonance frequency and the value of the length L. Is done.

Further, similarly to the first embodiment, by selecting the position of the feed hole 5, the radiation electrode 4 and the feed line 14 can be selected without changing the size of the surface mount antenna 1.
It is possible to match the impedance with zero.

[Third Embodiment] FIG. 4 is an exploded perspective view showing a third embodiment of the present invention and a state in which the surface mount antenna is mounted on a substrate. In this embodiment,
The same parts as those in the first and second embodiments, or corresponding parts, are denoted by the same reference numerals, and detailed description is omitted. Third
In the embodiment, compared to the first and second embodiments,
The position of the power supply hole 5, the power supply terminal electrode 7, and the substrate on which it is mounted are characterized.

That is, the power supply hole 5 is formed so as to reach the through hole 3 from the bottom surface 2 b of the dielectric substrate 2. Power supply hole 5
In the same manner as in the first and second embodiments, for example, by plating or applying a conductive paste, Cu,
A feed electrode 6 made of Ag, Ag-Pd, and Ag-Pt is formed and connected to the radiation electrode 4.

An annular power supply terminal electrode 7 is formed around the power supply hole 5 provided on the bottom surface 2 b of the dielectric substrate 2, and is connected to the radiation electrode 4 via the power supply electrode 6.

The fixing electrodes 8 for fixing to the substrate to be mounted are also formed at four locations only on the bottom surface 2b in FIG. 4, but the required fixing electrodes 8 are formed in the same manner as in the first and second embodiments. According to the strength and the manufacturing cost, the side surface 2c
To the bottom surface 2b or only on the side surface 2c. Also, the number and shape are appropriately selected.

Also in this embodiment, since the power is supplied to the radiation electrode 4 by the power supply hole 5 formed in the middle part in the longitudinal direction, the radiation electrode 4 is conventionally supplied for the reason described in the first embodiment. The length of the radiation electrode 4, that is, the length L of the surface mount antenna 1 is shorter than that supplied from the end of the radiation electrode.

Further, although not shown in FIG. 4, by forming end face electrodes on both end faces 2e and 2f of the dielectric substrate 2, a capacitance component is formed between the end face electrodes. The length L of the surface mount antenna 1 can be shortened for the reason described in the above.

Next, the mounting state of the surface mount antenna 1 on the substrate will be described. As shown in FIG. 4, on one main surface 100a of the mounting substrate 100, a power supply unit 110, a fixing conductor 180, a power supply line 140, and an earth conductor 190 serving as the fixing conductor are formed. Power supply unit 1
Reference numeral 10 denotes a power supply conductor 170, and a power supply line 140.
Is connected to

The surface mount antenna 1 includes a feed terminal electrode 7 and a fixing electrode 8 formed on the bottom surface 2 b of the dielectric substrate 2.
Are mounted so as to correspond to the power supply conductor 170, the fixing conductor 180, and the ground conductor 190 formed on one main surface 100a of the substrate 100, respectively, and are connected by, for example, a solder, an adhesive, or the like (not shown). Fixed.

That is, in the surface-mounted antenna 1, power is supplied from the power supply (not shown) to the radiation electrode 4 via the power supply line 140, the power supply conductor 170, the power supply terminal electrode 7, and the power supply electrode 6. Will be.

Further, similarly to the first and second embodiments, by selecting the position of the feed hole 5, the radiation electrode 4 and the feed line 140 can be selected without changing the size of the surface mount antenna 1. Can be matched.

In the first embodiment and the third embodiment, the shape and the position of the power supply section 110 formed on the substrate 100 on which the surface mount antenna 1 is mounted, the position of the power supply line 140, and the like are different. Is different. That is, in the first embodiment, the power supply conductor 170 formed on one main surface 100a of the substrate 100 is connected to the power supply line 140 formed on the other main surface 100b via the power supply hole 160. However, in the third embodiment, the power supply conductor 17
0 and the power supply line 140 are formed on one main surface 100a and are connected to each other.

This is appropriately selected depending on the position of the power supply hole 5 formed in the surface mount antenna 1 to be mounted, the position and shape of the corresponding power supply terminal electrode 7 and the fixing electrode 8, and the presence or absence of the end face electrode 9. Is what is done. That is,
The surface mount antennas of the first to third embodiments can be mounted on any of the substrates 100 disclosed in FIG. 2 or FIG. 4 according to conditions.

Although the planar shape of the dielectric substrate is rectangular throughout the first to third embodiments, it may be square. Although the through hole is also formed in the longitudinal direction, the gist of the present invention does not change even if it is formed in the short side direction.

[0055]

According to the present invention, there is provided a surface mount type antenna which can be directly mounted on a mounting board housed in a communication device such as a mobile phone without using a connector or the like, and furthermore, a radiation antenna. Since power is supplied to the electrode by the power supply hole formed in the middle part in the longitudinal direction, the inductance component of the power supply electrode formed in the power supply hole contributes to radiation, and the length of the radiation electrode That is, the length of the antenna can be reduced.

Further, by forming the end face electrode on the end face of the dielectric substrate, a capacitance component is formed between the end face electrodes, and the resonance frequency of the antenna is lowered. As a result, when applied to the same resonance frequency as the conventional one, the antenna length can be further reduced.

Further, by selecting the position of the feeding hole and changing the feeding position with respect to the radiation electrode, the impedance between the radiation electrode and the feeding line can be easily matched without changing the size of the antenna.

Therefore, the size of a communication device such as a portable telephone can be easily reduced by using the surface mount antenna of the present invention.

[Brief description of the drawings]

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

FIG. 2 is a perspective view showing a state in which the surface-mounted antenna according to the first embodiment of the present invention is mounted on a substrate.

FIG. 3 is a perspective view showing a surface mount antenna according to a second embodiment of the present invention.

FIG. 4 is an exploded perspective view for explaining a surface mounted antenna according to a third embodiment of the present invention and a mounting state on a substrate.

FIG. 5 is an exploded perspective view showing an antenna according to a conventional example of the present invention.

FIG. 6 is a perspective view showing a surface mount antenna according to a conventional example of the present invention and a mounting state thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Surface mount type antenna 2 Dielectric substrate 2a Top surface 2b Bottom surface 2c, 2d Side surface 2e, 2f End surface 3 Through hole 4 Radiation electrode 5 Feed hole 6 Feed electrode 7 Feed terminal electrode 9 End electrode 100 Substrate 110 Feed unit

Claims (3)

(57) [Claims] 1. A pillar-shaped dielectric substrate having at least one through hole, mounted on the substrate via one surface of the dielectric substrate, and an inner peripheral surface of the through hole from a power supply unit provided on the substrate. Wherein the dielectric substrate is formed on a feed hole reaching the through hole from a surface of the dielectric substrate, and on an inner peripheral surface of the feed hole. A surface-mounted antenna having a power supply electrode and a power supply terminal electrode connected to the power supply electrode, wherein the power supply terminal electrode is connected to a power supply unit provided on the substrate. 2. A columnar dielectric substrate having at least one through hole, mounted on the substrate via one surface of the dielectric substrate, and an inner peripheral surface of the through hole from a power supply unit provided on the substrate. Wherein the dielectric substrate is formed on a feed hole reaching the through hole from a surface of the dielectric substrate, and on an inner peripheral surface of the feed hole. A power supply electrode, a power supply terminal electrode connected to the power supply electrode, and an end surface electrode formed on at least one end surface of the dielectric substrate and connected to the radiation electrode, wherein the power supply terminal electrode is provided on the substrate. A surface-mounted antenna connected to a feeding unit. 3. The surface mount antenna according to claim 1, wherein the feed hole is formed on a side surface, a top surface, or a bottom surface of the dielectric substrate.