WO1997019488A1

WO1997019488A1 - Antenna

Info

Publication number: WO1997019488A1
Application number: PCT/JP1996/003315
Authority: WO
Inventors: Mitsuya Makino
Original assignee: Nippon Antena Kabushiki Kaisha
Priority date: 1995-11-22
Filing date: 1996-11-12
Publication date: 1997-05-29
Also published as: KR19980701595A; CN1172555A; TW351023B; JP3431379B2; JPH09148827A; EP0805506A1

Abstract

When the antenna element of an antenna is expanded, a helical element (4) acts as a parasitic element, and a high-frequency current flows through an element conductor (3), causing the element (4) to act as a parasitic element which is excited in a high frequency wave way. When the antenna element is housed, electrical energy is fed to the upper end of the element (4) from the upper end of an upper conductor section (6), and the overlapping parts of the element (4) and section (6) form an L-C parallel resonance circuit. Therefore, the antenna makes two-resonance operation.

Description

Description Antenna Technical field

The present invention relates to an antenna slidably provided in a housing, and is particularly suitable for being applied to a portable radio telephone. Background art

An outline of this type of conventional antenna is shown in Figs. 5 (A) and 5 (B). In the type A antenna shown in FIG. 5 (A), an insulating portion 106 is provided on the element conductor 103 as described in Japanese Patent Application Laid-Open No. 6-216630. Antenna element and a helical element 104. The antenna element can be housed in the housing 100 by sliding inside the helical element 104, and the housed antenna element can be extended from the housing 100. The helical element 104 is fixedly provided in the upper projecting portion of the housing 100.

The state where the antenna element of such an antenna is extended by sliding is shown in (a) of FIG. 5 (A). In this case, a signal from the signal source 102 in the housing 100 is supplied to the power supply unit 105 via the matching circuit (MC) 101. Then, the power supply section 105 is electrically connected to the lower end of the element conductor 103 and the lower end of the helical element 104, and the element conductor 103 and the helical element 104 are brought into an operating state.

The state where the antenna element is slid and housed in the housing 100 is shown in FIG. In this case, the signal from the signal source 102 in the housing 100 is supplied to the power supply unit 105 through the matching circuit (MC) 101, but the power supply unit 105 is The helical element is electrically connected to only the lower end of the cull element 104. Only 104 is in operation.

In this case, the insulating part 106 formed on the upper part of the antenna element is located within the helical element 104 so that the antenna element does not affect the helical element 104. .

Fig. 5 (B) shows an outline of a conventional Evening B antenna with a different configuration from the above-mentioned antenna. As described in Japanese Patent Application Laid-Open No. 2-271701, this antenna has an antenna element in which an insulating portion 106 is provided on the upper and lower portions of a coil-shaped element conductor 103. And helical element 104. The antenna element can be housed in the housing 100 by sliding inside the helical element 104, and the housed antenna element can be extended from the housing 100.

The helical element 104 is fixedly provided in the upper protruding portion of the housing.

The state where the antenna element of such an antenna is extended by sliding is shown in (a) of FIG. 5 (B). In this case, the signal from the signal source 102 in the housing 100 is supplied to the power supply unit 105 via the matching circuit (MC) 101. Then, the power supply section 105 is electrically connected to the lower end of the helical element 104, and the helical element 104 is excited. Since the helical element 104 and the coil-shaped element conductor 103 are inductively coupled, when the helical element 104 is excited, the inductively coupled element conductor 103 is also excited. become.

Therefore, the antenna element and the helical element 104 are brought into an operating state. At this time, the insulating portion 106 formed below the antenna element is located in the helical element 104.

The state where the antenna element is slid and housed in the housing 100 is shown in FIG. In this case, the signal from the signal source 102 in the housing 100 is supplied to the power supply unit 105 via the matching circuit (MC) 101, and is connected to the power supply unit 105. The helical element 104 is brought into operation. At this time, the coil-shaped element conductor 103 is housed in the housing 100 and is in a non-operating state.

In this case, the insulating part 106 formed on the upper part of the antenna element is located in the helical element 104 so that the antenna element does not affect the helical element 104.

Next, the operation of the antenna will be described. In the conventional antenna of the above-mentioned Eve A, when the antenna element is extended, the element conductor 103 and the helical element 104 are connected in parallel. At this time, the helical element 104 has a function of increasing the equivalent thickness of the element conductor 103, and as a result, the frequency-impedance characteristic shows a wider band than the element conductor 103 alone. The characteristics of the frequency-to-voltage standing wave ratio (VSWR) at this time are shown as type A in Fig. 3 (a), but the resonance frequencies of the helical element 104 and the element conductor 103 are set to be the same. Therefore, a single resonance characteristic is obtained.

In addition, in the conventional type A antenna, when the antenna element is housed, only the helical element 104 operates and becomes an L-C series resonance antenna. Therefore, the characteristic of the frequency vs. V SWR at this time is a single resonance characteristic as shown as types A and B in FIG. 3 (b).

In the above-mentioned conventional evening E antenna, when the antenna element is extended, the helical element 104 is connected to the feeding unit. At this time, the helical element 104 is inductively coupled to the element conductor 103, which is a parasitic element, and provides high-frequency excitation to the element conductor 103. The characteristics of the frequency to voltage standing wave ratio (VS WR) at this time are shown as type B in Fig. 3 (a), but the resonance frequencies of the helical element 104 and the element conductor 103 are set to be the same. Therefore, a single resonance characteristic is obtained.

In addition, in the conventional type B antenna, when the antenna element is housed, only the helical element 104 operates and becomes an L-C series resonance antenna. Therefore, the characteristics of frequency vs. VS WR at this time are shown in Fig. 3 (b). As shown in types A and B, single resonance characteristics are obtained.

By the way, in a mobile phone, as shown on the frequency axis shown in FIG. 3, the transmission band of the mobile station and the reception band of the mobile station are assigned to different frequency bands. Therefore, it is necessary for the antenna of the mobile phone to have characteristics that cover the transmission band and the reception band.

However, as shown in Fig. 3, the conventional type A and type B antennas exhibit single resonance characteristics when both extended and retracted, so that favorable characteristics covering the transmission band and the reception band can be obtained. There was a problem that not.

Therefore, an object of the present invention is to provide an antenna that can cover a transmission band and a reception band assigned to different frequency bands when the antenna is expanded and stored. Disclosure of the invention

In order to achieve the above object, an antenna according to the present invention includes an antenna element having an upper conductor portion above an element conductor via an insulating portion, and an antenna having a helical element. When the antenna element is extended, the lower end of the antenna element is used as a feeding portion, and when the antenna element is housed, the helical antenna is extended. The upper end of the element is connected to the upper end of the upper conductor, and the lower end of the upper conductor serves as a power supply.

In the antenna, the antenna element is slidable in a holder conductor connected to a circuit in the housing, and when the antenna element is extended, a lower end of the antenna element is connected to the holder conductor. The lower portion of the upper conductor portion and the holder conductor are connected in a state where the antenna element is housed,

Further, when the antenna element is extended and stored, the antenna The element and the helical element operate as a two-resonance antenna.

According to such an antenna of the present invention, the antenna consisting of the antenna element and the helical element performs two resonance operations, so that the transmission band and the reception band respectively assigned to different frequency bands are extended and retracted. The characteristics of the antenna that can cover the band can be obtained. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 (a) is a diagram showing an outline of the configuration of the antenna of the present invention at the time of extension, and FIG. 1 (b) is a diagram showing the antenna of the present invention at the time of storage. FIG. 3 is a diagram showing an outline of a configuration.

FIG. 2 (a) is a diagram showing a detailed configuration example of the antenna of the present invention at the time of extension, and FIG. 2 (b) is a diagram showing the antenna of the present invention at the time of storage. FIG. 3 is a diagram illustrating a detailed configuration example.

FIG. 3 (a) is a diagram showing the characteristics of the frequency vs. VSWR when the antenna of the present invention and the conventional antenna are expanded. FIG. 3 (b) is a diagram showing the characteristics of the antenna of the present invention and the conventional antenna. FIG. 7 is a diagram showing characteristics of frequency vs. VS WR when the is stored.

FIG. 4 is a diagram showing another example of the detailed configuration of the embodiment of the antenna of the present invention.

FIG. 5 (A) is a diagram showing an outline of a configuration of a conventional type A antenna, and FIG. 5 (B) is a diagram showing an outline of a configuration of a conventional type B antenna. BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described in more detail with reference to the accompanying drawings.

FIGS. 1 (a) and 1 (b) show a schematic configuration of an embodiment of the antenna of the present invention. In FIGS. 1 (a) and 1 (b), the antenna is located above an element conductor 3. The antenna element includes an antenna element having an upper conductor portion 6 formed via an insulating portion 8, and a helical element 4.

In this antenna, the antenna element is made to slide inside the helical element 4 so as to be able to protrude and retract from the housing 10, and the antenna element is housed in the housing 10 as shown in FIG. 1 (b). Fig. 1 (a) shows a state where the antenna element is extended from the housing 10 as shown in Fig. 1 (a). The helical element 4 is fixedly provided in the upper protruding portion of the housing 10.

When the antenna element of such an antenna is extended, a signal from the signal source 2 in the housing 10 is supplied to the feed unit 5 via the matching circuit (MC) 1. Then, the power supply unit 5 is electrically connected to the lower end of the element conductor 3, and the element conductor 3 is brought into an operating state. At this time, the helical element 4 is a parasitic element connected to nowhere, but the helical element 4 is excited at a high frequency by the high-frequency current flowing through the element conductor 3.

Also, when the antenna element is housed in the housing 10 as shown in FIG. 2B, the signal from the signal source 2 in the housing 10 is fed through the matching circuit (MC) 1 The power is supplied to the section 5, and the feed section 5 is electrically connected to the lower end of the upper conductor section 6 above the antenna element. Further, the upper end of the helical element 4 is electrically connected to the upper end of the upper conductor 6 at the connection point 7. Therefore, the helical element 4 is driven via the upper conductor 6.

In this case, the element conductor 3 is insulated from the upper conductor section 6 by the insulating section 8 and is brought into a non-operating state.

Next, the operation of the antenna according to the present invention will be described. When the antenna element is extended, the element conductor 3 is connected to the feed section 5 to excite the element conductor 3. At this time, the helical element 4 acts as a parasitic element that is excited at a high frequency by the high-frequency current flowing through the element conductor 3, for example, the resonance frequency of the helical element 4 is set to the center frequency of the mobile station reception band, Since the resonance frequency of the element conductor 3 is set to the center frequency of the mobile station transmission band, two resonance characteristics can be obtained in the frequency versus impedance characteristics. That is, as shown in FIG. 3 (a), the characteristics of the frequency to voltage standing wave ratio (VS WR) of the antenna at the time of extension cover the allocated mobile station transmission band and mobile station reception band as shown in the present invention. Yes Two resonance characteristics.

In the antenna of the present invention, when the antenna element is housed, the upper conductor 6 is connected to the feeder 5, and the upper end of the upper conductor 6 is connected to the helical element 4. Distribution capacity occurs at the overlap between 6 and helical element 4. Therefore, an L-C parallel resonance circuit is formed, and a different resonance frequency different from the natural resonance frequency of the upper conductor 6 can be obtained. Thereby, two resonance characteristics can be obtained.

That is, as shown in FIG. 3 (b) as the present invention, the frequency of the antenna when housed and the V SWR characteristics are two resonances covering the allocated mobile station transmission band and mobile station reception band. Characteristics.

As described above, the antenna of the present invention makes the resonance frequencies of the element conductor 3 and the helical element 4 different to cover the mobile station transmission band and the mobile station reception band during extension and storage. The operation is performed, and an example of the detailed configuration is shown in FIGS. 2 (a) and 2 (b).

FIG. 2 (a) is a diagram illustrating a state where the antenna element is extended from the housing 10, and FIG. 2 (b) is a diagram illustrating a state where the antenna element is housed in the housing 10.

The antenna element shown in Figs. 2 (a) and (b) has an insulative antenna top 13 formed at the tip, and an upper conductor section is formed on the outer periphery of the lower part of the extension extending downward from the antenna top 13. 6 is inserted. The lower end of the extended portion of the antenna top 13 protrudes from the lower end of the upper conductor portion 6, and the extended portion and the upper end of the element conductor 3 are integrated by molding.

An insulating tube 9 is fitted around the outer periphery of the element conductor 3, and A stopper conductor 11 is fitted into the lower end of the component conductor 3 from above the insulating tube 9, and the element conductor 3 and the stopper conductor 11 are electrically connected. Such an antenna element is slidably inserted into the helical element 4 housed in the external protrusion of the housing 10 and slidably inserted into the holder conductor 12 fixed to the housing 10. The holder conductor 12 is electrically connected to the matching circuit 1, and the matching circuit 1 is connected to the signal source 2.

When the antenna transmits, the final stage of the transmission unit provided in the housing 10 corresponds to the signal source 2. When the antenna receives, the signal source 2 is the housing 10. It corresponds to the received signal supplied to the receiving unit provided in the inside.

Then, as shown in FIG. 2 (a), when the antenna element is extended, the stopper conductor 11 fitted at the lower end of the element conductor 3 becomes the holder conductor 1

The signal source 2 connected via the matching circuit 1 is connected to the element conductor 3 via the holder conductor 12 and the stopper conductor 11 by being inserted into and electrically connected to the element conductor 3. At this time, the high frequency current flowing through the element conductor 3 causes the helical element 4, which is a parasitic element connected to nowhere, to be coupled with the element conductor 3 at a high frequency, and the helical element 4 becomes a parasitic element. Operate.

Note that the upper conductor 6 does not function as an antenna due to the action of the insulating part 8. When the antenna element is housed in the housing 10 as shown in FIG. 2B, the antenna top 13 abuts against the external projection of the housing 10 and the upper conductor 6 is a helical element. 4 and the lower part thereof is inserted into the holder conductor 12 to be electrically connected. Therefore, the signal source 2 connected via the matching circuit 1 is connected to the lower portion of the upper conductor 6 via the holder conductor 12. At this time, the upper end of the upper conductor 6 is connected to the upper end of the helical element 4, so that a high-frequency current flows through the upper conductor 6 and the helical element 4.

Note that the element conductor 3 is brought into a non-operating state by the action of the insulating portion 8. The overlapping part of the upper conductor 6 and the helical element 4 is an L-C parallel resonance circuit. Will be constituted.

Next, another example of the detailed configuration of the antenna of the present invention is shown in FIG. The antenna shown in this figure is different from the configuration of the antenna shown in FIGS. 2 (a) and 2 (b) in that it is not integrated with the housing 10 but is formed independently. Since the operation of the antenna is the same as that of the antenna shown in FIGS. 2 (a) and 2 (b), a detailed description thereof will be omitted, and the differences will be described.

FIG. 4 shows a state in which the antenna element is extended, and a stopper 11 electrically connected to a lower end of the element conductor 3 inserted and arranged in the insulating tube 9 is attached to a lower end of the holder conductor 12. I'm in opposition. At this time, the holder conductor 12 and the element conductor 3 are connected, and the element conductor 3 is connected to the matching circuit 1 and the like included in the housing 10.

The helical element 4, which is a parasitic element that is coupled to the element conductor 3 at high frequency by the high-frequency current flowing through the element conductor 3, is disposed in a helical element cover 14 formed of resin or the like. I have. The helical element cover 14 is fixed on the upper part of the holder conductor 12.

When mounting the antenna configured as described above on the housing 10, use the mounting screw 12-1 formed on the lower part of the holder conductor 12 to mount the antenna on the housing 10. do it.

In the above-described antenna of the present invention, since the element conductor 3 is formed of a material having elasticity, the element conductor 3 covered with the insulating tube 9 has flexibility, and the extended antenna element is an obstacle. Even if it collides with an object or the like, breakage of the antenna element can be prevented.

When the antenna is extended and retracted, the operation mode of the antenna can be arbitrarily set at about 1/4 wavelength to about 12 wavelengths. In this case, the matching circuit 1 can be omitted under conditions close to 14 wavelengths. Industrial applicability As described above, the antenna of the present invention is configured so that the resonance frequency of the element conductor is different from the resonance frequency of the helical element. When power is supplied to the helical element due to the two-resonance operation, the overlapping portion of the upper conductor and the helical element forms an L-C parallel resonance circuit, resulting in the two-resonance operation. For this reason, the antenna of the present invention can be a two-resonance antenna that can cover the mobile station transmission band and the mobile station reception band when extended and retracted, and can be applied to portable equipment, especially portable radio telephones. It is suitable.

0

Claims

The scope of the claims

1. An antenna element having an upper conductor portion above an element conductor via an insulating portion, and an antenna having a helical element,

The antenna element is made expandable and contractible by sliding in the helical antenna. In a state where the antenna element is extended, a lower end of the antenna element is used as a feeding unit, and the antenna element is stored. In the antenna, the upper end of the helical element and the upper end of the upper conductor are connected to each other, and the lower end of the upper conductor serves as a feeder.

2. The antenna element is slidable in a holder conductor connected to a circuit in the housing, and in a state where the antenna element is extended, a lower end of the antenna element is connected to the holder conductor, and the antenna element 2. The antenna according to claim 1, wherein a lower portion of the upper conductor and the holder conductor are connected in a state where the antenna is stored.

3. The antenna according to claim 1, wherein the antenna element and the helical element operate as a two-resonant antenna when the antenna element is extended and housed.

Claims of amendment

[March 25, 1977 (25.0.3.97) Accepted by the International Bureau: The original claim ffl 1 has been replaced by amended claims 1 and 2. (1)]

1. (After correction) An antenna element having an upper conductor section above an element conductor via an insulating section, and an antenna having a helical element,

The antenna element is made expandable and contractible by sliding in the helical antenna. In a state where the antenna element is in a middle position, the end of the antenna element is used as a power supply unit, The above-mentioned spiral antenna, which is a range element, is excited at a high frequency by the above-mentioned antenna element,

In the state where the antenna element is housed, the fin end of the helical element is connected to the fin end of the upper conductor part whose lower end is a feeding part, and the upper conductor part and the helical antenna are connected. An antenna, wherein the antenna element and the helical element operate as a two-resonance antenna when the antenna element is extended and housed by forming a parallel resonance circuit by the overlapping portion.

2. The antenna element is slid in the holder conductor connected to the circuit in the entrapment, and in a state where the antenna element is extended, the lower end of the antenna element is force-connected to the holder conductor, 4. The antenna according to claim 3, wherein a lower portion of said upper conductor portion and said holder conductor are connected in a state where said antenna element is housed.

3. (Delete) Description based on Article 19 of the Treaty Article 1 of the Claims states that, when the antenna element is extended and retracted, the antenna element and the helical element work together to operate as a two-coaxial antenna. Clarified that.

Antenna operating as a two-resonance antenna in any of the cited reference does not disclose _t