KR100441922B1 - Dual-band antenna and adjusting method of frequency thereon - Google Patents

Abstract

The dual-band antenna according to the present invention is a fixed antenna of a communication device, the outer side of the antenna by making a contact with the sleeve and the insulator formed on one end of the sleeve and the connector and connector formed on the other end of the sleeve A contact terminal which extends in contact with a circuit of a communication device, a conductive feed portion fixed to a central portion of the insulator and extending downward, a helical formed outside the feed portion, and an insulator outside the feed portion; It is formed long between the connector, characterized in that it comprises a dielectric interposed between the feed portion and the helical so that the capacitive component is generated between the feed portion and the helical.

In addition, the frequency adjustment method of the dual-band antenna according to the present invention, in the method for adjusting the resonant frequency of the fixed antenna, by cutting the entire length of the helical to adjust one resonant frequency to the center frequency of the low frequency of the dual band adjustment Making; Adjusting the resonant frequency to the center frequency of the high frequency of the dual band by adjusting the length of the feed portion interposed between the dielectric inside the helical and inserted into the dielectric.

According to the present invention, it is possible to conveniently and accurately match the center frequency and resonant frequency of radio waves transmitted and received by the dual band antenna.

Description

Dual-band antenna and adjusting method of frequency thereon}

The present invention relates to a dual band antenna for transmitting / receiving a dual band frequency, and more particularly, to a configuration of a dual band antenna capable of stably transmitting / receiving a frequency used in a mobile communication device and a resonance frequency of an antenna. It is about an adjustment method.

In various mobile communication services, frequencies that can be used for each are determined, and each frequency is allocated and used for each service type or service area.

For example, CDMA (Code Division Multiple Access), GSM (GSM: Global System for Mobile Telecommunication), IMT-2000 (IMT-2000), and DCS (Digital Communication System), Different frequencies are used. In addition, these frequencies are generally used in conjunction with each other.

In addition, referring to the center frequency of the frequency band used in each of the communication methods described above, 859 MHz in the CD Division (CDMA) method, 920 MHz in the Global System for Mobile Telecommunication (GSM), 2042.5MHz is used in MMT-2000 and 1805MHz is used in DCS (DCS). In particular, the methods that can be interlocked with each other are the CD method and the PS method, the GS method and the DC method, the CD method and the IMT 2000 method and the PC and IMT 2000 method interworking Can be used.

On the other hand, it is necessary to use a communication method having a different frequency band is interlocked with each other. As described above, a method of applying a single mobile communication device by interworking a system having a different frequency band is called a dual band method.

On the other hand, the types of antennas include a flexible antenna (Whip antenna) that the elements of the antenna is stretchable, and a fixed antenna (stubby antenna) in which the elements of the antenna is fixed without stretching or shrinking, the object of the present invention is a fixed antenna to be.

In the related art, in order to apply the dual band method, since the small antenna for the terminal is individually used for each of the two bands, the material cost is high and the inconvenience of rework has many problems. In addition, since high power consumption is required, there is also a problem that the life of the battery is shortened.

As a method to solve this problem, the proposed method includes helical capable of receiving radio signals, dense helical with dense helical and small helical with little helical. Helical has a dual structure in which portions are formed, respectively, so that different kinds of frequency bands can be simultaneously transmitted and received. Hereinafter, with reference to the drawings will be described in more detail.

1 is a cross-sectional view of a conventional dual band antenna.

Referring to FIG. 1, a sleeve 1 forming an outer circumference of an antenna, a helical 3 formed on an inner side of the sleeve 1 to receive a frequency, and a metal fitted to one end of the helical 3 ( For example, a connector 4 of brass and an insulator 2 of plastic material inserted into the helical 3 from the other end of the connector 4 are included.

Further, there is further formed a wire 5 connected with the connector 4 for allowing the signal received by the connector 4 to be transferred into the terminal.

However, in the method of receiving a frequency by a dual band antenna that forms a dual helical to receive a dual band frequency, when the reception is focused on one frequency band (eg, SM), the other side is received. There is a problem in that it is difficult to accurately adjust the center frequency of the reception frequency in the frequency band (for example, DC) of which there is a problem in that a high gain cannot be compensated, and there is a problem in receiving the correct frequency band.

FIG. 2 is a chart of the frequency-to-voltage standing wave (VSWR) ratio of the conventional dual band antenna shown in FIG.

Referring to FIG. 2, a high gain can be obtained for the center frequency F1 of the GS communication band, but a resonance frequency is set outside the center frequency band used for the center frequency F2 of the DS communication band. Since the gain (efficiency) does not reach 20% in F2 compared to F1, high transmission and reception efficiency cannot be obtained.

This phenomenon is due to the fact that the helical used for transmission and reception cannot be accurately formed. In detail, there is a limit to strictly adjusting the resonant frequency by controlling the pitch, width, line width, spacing, and number of turns of the helical as in the prior art.

As such, when the position of the center frequency used in the dual band and the resonant frequency of the antenna is changed, only when a lot of output is consumed inside the terminal, transmission and reception are possible, and furthermore, communication is performed where radio waves are weakly received. There is a problem that can not be done.

In the conventional dual band antenna that has been proposed in such a double helical form, there is a type as shown in the Republic of Korea application number "20-2002-0012483", "helical antenna of a portable terminal", this structure is a general dual band antenna The form of is illustrated in more detail.

The present invention has been made to solve the problems described above, and an object of the present invention is to propose a structure of an antenna capable of more accurately matching a center frequency transmitted and received by an antenna with a resonance frequency of the antenna.

It is also an object of the present invention to propose a method for more accurately adjusting the resonance frequency of the dual band antenna according to the present invention. In particular, it is an object to be able to adjust the resonant frequency of the dual-band antenna that can accurately match both the center frequency band of the dual used.

In addition, an object of the present invention is to propose a structure of a dual band antenna capable of more accurately matching a resonant frequency of a terminal to a center frequency of a frequency band used, and capable of transmitting and receiving radio waves even at low power.

1 is a cross-sectional view of a conventional dual band antenna.

FIG. 2 is a plot of the frequency versus voltage standing wave (VSWR) ratio of the conventional dual band antenna shown in FIG.

3 is a cross-sectional view of a dual band antenna according to the spirit of the present invention.

4 is an exploded perspective view of a dual band antenna according to the present invention;

5 is a flowchart for explaining a method of adjusting a resonant frequency of a dual band antenna according to the present invention.

6, 7 and 8 are diagrams of frequency-voltage standing wave ratios for explaining the frequency adjusting method in the dual band antenna of the present invention.

<Explanation of symbols for the main parts of the drawings>

DESCRIPTION OF SYMBOLS 1 Sleeve 2 Insulator 3 Helical 4 Connector

5 wire 11 sleeve 12 insulator 121 feeder

13: helical 131: dense helical 132: small helical 14: connector

15 contact terminal 16 dielectric

A dual band antenna according to the present invention for achieving the object as described above, in the fixed antenna of the communication device, the sleeve and the insulator formed on one end of the sleeve and the connector formed on the other end of the sleeve And a contact terminal extending from the outside of the antenna in contact with the connector to be in contact with the circuit of the communication device, a conductive feed portion fixed to the center of the insulator and extending downward, and a helical formed outside the feed portion. And a dielectric formed long between the insulator and the connector to the outside of the feed portion, interposed between the feed portion and the helical to generate a capacitive component between the feed portion and the helical. It is done.

In the method for adjusting the resonant frequency of a dual band antenna according to the present invention, in the method of adjusting the resonant frequency of a fixed antenna, the entire length of the helical is cut to adjust one resonant frequency to the center frequency of the low frequency among the dual bands. Adjusting; Adjusting the resonant frequency to the center frequency of the high frequency of the dual band by adjusting the length of the feed portion interposed between the dielectric inside the helical and inserted into the dielectric.

By the above-described configuration of the dual band antenna and the method of adjusting the center frequency of the dual band antenna, the resonance frequency of the antenna can be adjusted more accurately, and the radio waves can be transmitted and received even at a low output, thereby further improving the user's convenience. It works.

Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings. However, the spirit of the present invention is not limited to the embodiments in which the present invention is presented, and those skilled in the art who understand the spirit of the present invention may change other embodiments by changing, adding, or deleting components within the scope of the same spirit as the present invention. It can be presented easily.

3 is a cross-sectional view of a dual band antenna according to the spirit of the present invention.

Referring to FIG. 3, in the dual band antenna according to the spirit of the present invention, a helical in which dense helical 131 and small helical 132 are formed, respectively; 13), a conductive feed portion 121 inserted into a substantially central portion of the insulator 12 and extending downward, a dielectric 16 interposed between the helical 13 and the feed portion 121; A conductive connector 14 inserted into and fixed to one end of the dielectric 16, a contact terminal 15 for transmitting a signal transmitted and received by making contact with the connector 14, and a sleeve forming an exterior of the antenna ( 11) is included.

The dielectric 16 is a cylindrical part interposed between at least the helical 13 and the feeder 121, and not only functions as a bobbin in which the helical 13 is wound, but also the connector 14 is inserted. Position is fixed. In other words, the dielectric 16 is interposed between the helical 13 and the feeder 121 to serve as a capacitor for generating an electrostatic induction capacity.

In addition, the insulator 12 and the sleeve 11 are ABS resin, urethane resin or P.V.C. It is preferable that resin is used. The helical 13 is formed of an integral spring in which a dense part and a small part are connected at the same time, but it is preferable to adjust the line width.

Briefly describing the operation of a dual band antenna such as the described configuration, a low frequency reception is achieved among the dual bands depending mainly on the overall length of the helical 13. In addition, the corresponding portion of the high frequency of the dual band can be adjusted by the capacitive C of the dielectric 16 interposed between the dense helical 131 and the feed section 121. have.

In particular, when the length of the feed unit 121 is changed, the electrostatic induction capacitance generated by the dielectric 16 is changed, so that the resonant frequency of the high frequency among the dual bands may be finely adjusted.

4 is an exploded perspective view of a dual band antenna according to the present invention.

Referring to FIG. 4, a helical 13 is wound around an outer circumference of the cylindrical dielectric 16, and an insulator 12 having a feed part 121 fixed thereto is inserted into an upper end of the dielectric 16. The connector 14 is inserted and fixed to the lower end of the dielectric 16. In addition, the exterior of the antenna may be fixed by being fitted with an end portion of the lower side of the insulator 12 and an upper end of the sleeve 11.

In addition, the contact terminal 15 formed at the lower end of the sleeve 11 forms a contact with the connector 11 so that the radio wave received by the helical 13 can be smoothly transmitted to the mobile communication device.

5 is a flowchart for explaining a method of adjusting a resonant frequency of a dual band antenna according to the present invention.

Referring to FIG. 5, the process of matching the resonance frequency of the antenna will be described. First, the length of the antenna is longer than necessary, and the dense helical 131 and the small sloping ) Helical 132 is continuously formed integrally formed by forming a helical, and the process of cutting the upper end of the dense (dense) helical 131 one of the antenna at the center frequency of the lower frequency of the dual band The resonance frequency of is set.

This process can be understood by the diagram of the frequency-voltage standing wave ratio of FIG. 6. In detail, the standing wave ratio diagram 21 before adjusting the dense helical (see 131 of FIG. 3) is shown. For reference, it can be seen that the resonance frequency of the antenna is formed at a higher position than the center frequencies R1 and R2 of the dual band. However, the resonant frequency is rapidly changed by adjusting the length of the dense helical 131, and as a result, the resonant frequency is near the center frequencies R1 and R2. You can see that is located. For example, referring to the standing wave ratio diagram 22 after the dense helical is adjusted, it can be seen that a resonance frequency is formed at a position substantially coincident with the center frequencies R1 and R2 of the dual band. (ST 11)

On the other hand, the position of the resonant frequency changes abruptly as the entire length of the helical changes abruptly by cutting the dense helical 131 wound tightly.

Then, after the position of the resonant frequency corresponding to the low frequency in the dual bands is adjusted by cutting the entire length of the dense helical 131, it is small. The position of the resonant frequency is adjusted by adjusting the length of the helical 132. In detail, since the entire length of the helical 13 does not change suddenly in the process of adjusting the length of the small helical 132, the position of the resonance frequency can be finely adjusted. (ST 12).

Referring to Fig. 7, the plot 23 of standing wave ratio after adjustment of small (sparse) helical is compared with the plot 22 of standing wave ratio after adjustment of dense helical. In more detail, it can be seen that the center frequencies R1 and R2 of the dual band coincide with the positions of the resonance frequencies.

After the lengths of the dense helical 131 and the small helical 132 are adjusted, the length of the feed section 121 is adjusted. In detail, since only the length of the feeder 121 is adjusted, there is almost no change in the center frequency of the low frequency in the dual bands, but only the resonance frequency for receiving the center frequency of the high frequency in the dual bands is changed.

In detail, the resonant frequency is changed by changing the capacitance C between the dense helical 131 and the power feeding portion 121, and the resonant frequency of the helical 13 changes in such a resonant frequency. Since there is no change in the overall length, the resonant frequency of the low frequency portion of the dual band is hardly changed, but changes only in the resonant frequency of the high frequency portion of the dual band (ST 13). That is, by changing the space or spacing between the dense helical 131 and the power feeding portion 121 by the dielectric 16, the resonance frequency is changed, and in particular, the high frequency in the dual band is high. Since the resonant frequency can be changed to the center frequency position of the frequency, all frequencies of the high frequency and the low frequency of the dual band can be normally transmitted and received.

Referring to FIG. 8, when the standing wave ratio diagram 24 after adjusting the length of the feeder 121 and the standing wave ratio diagram 23 after adjusting only the length of the helical 13 is compared, the lower frequency among the dual bands is shown. In the state where the center frequency R1 and the resonant frequency of R are coincident with each other, the resonance frequency of the higher frequency among the dual bands is shifted in the direction coinciding with the center frequency R2.

By this series of methods, both the resonant frequency of the antenna can be adjusted to be adjusted to the position of both the low frequency band and the high frequency band of the dual band.

On the other hand, by adjusting the length of the dense helical 131 (ST 11), after the center frequency and the resonant frequency of the low frequency band are relatively accurately matched, they are separately separated. The length of the helical 132 is adjusted without adjusting the length of the power supply unit 121 (ST 13), so that only the center frequency and the resonant frequency of the high frequency band need to match. In other words, even if the process of cutting the small helical 132 is eliminated, adjustment of the resonance frequency of the antenna according to the inventive concept can be achieved.

On the other hand, in another aspect of the present invention, in the process of forming the resonant frequency of the antenna, the helical turn, width, line width, spacing, etc. are produced in a fixed state and then dense (dense) By cutting and adjusting the lengths of the helical and small helical, and in addition, adjusting the length of the feed section, it is possible to more conveniently adjust the resonant frequency of the dual band antenna. The dense helical has a short pitch of the helical, and the minor helical has the same meaning as the long pitch of the helical.

The structure of the dual band antenna and the resonant frequency adjustment method of the dual band antenna according to the spirit of the present invention is a CD Division (Code Division Multiple Access), GSM (GSM: Global System for Mobile Telecommunication), IMT-2000 ( In addition to the frequency band used for mobile communication such as IMT-2000 and Digital Communication System (DCS), the present invention can be applied to a base station of a wireless telephone or a mobile communication network using dual bands.

In particular, the idea of the present invention is characterized by allowing the signal of a specific desired resonant frequency to be transmitted and received by adjusting the length of the feeder to generate the electrostatic inductance by interaction with the helical. Is obtained by the inventors' long-term experiments and the like, and should not be regarded as a simple cooking choice.

According to the present invention, it is possible to conveniently and accurately match the center frequency and resonant frequency of radio waves transmitted and received by the dual band antenna.

In particular, the method of accurately matching both the center frequency band of both the low frequency and the high frequency used in dual makes the use of the antenna manufacturer and the communication device more convenient, and the sensitivity of the communication device can be increased. Therefore, a dual band antenna capable of transmitting and receiving radio waves even at low power can be obtained. Further, since the antenna of the present invention can be exactly matched to the reception band, a separate matching circuit is provided inside the communication device. Since it does not need to be implemented, the manufacturing cost of the antenna can be reduced.

Claims (4)

In the fixed antenna of the communication device, A sleeve forming an exterior of the fixed antenna and an insulator formed on an upper end of the sleeve; A conductive connector formed at a lower end of the sleeve, A contact terminal which contacts the communication device by making a contact with the connector and extending out of the antenna; A conductive feeding part fixed to the insulator and extending downward; Helical is formed on the outer side of the feeding portion, the helical to be directly in contact with the connector to transmit and receive a signal, A dielectric is disposed between the feeder and the helical in a horizontal direction and between the insulator and the connector in a vertical direction, so that a dielectric component is generated to generate a capacitive component between the feeder and the helical. Dual band antenna characterized by. The method of claim 1, And the helical forms a helical having a short pitch at least as long as the feed portion, and a length beyond the feed portion is a double helical forming a helical having a long pitch. In the method of adjusting the resonant frequency of a fixed antenna without a specific load that is inserted into the communication device, the electric wave transmitted and received through the helical and the helical and the connector is in contact with the communication device, Cutting and adjusting the entire length of the helical to adjust one resonance frequency to a center frequency of low frequency among the dual bands; Adjusting the resonant frequency to the center frequency of the high frequency of the dual band by interposing a dielectric inside the helical and adjusting the length of the feed portion interpolated into the dielectric of the dual band antenna Resonant frequency adjustment method. The method of claim 3, wherein If the helical is a dual helical having a different pitch, the helical first adjusts the helical having a short pitch, and then adjusts the length of the helical having a long pitch.