KR20100054510A - Home repeater having helical antenna - Google Patents

Abstract

The present invention relates to a wireless communication repeater having a helical antenna. A repeater according to an embodiment of the present invention, a link antenna for transmitting and receiving a signal with a base station, a service antenna for transmitting and receiving a signal with a mobile communication terminal, and a repeater circuit for amplifying bidirectional signals between the link antenna and the service antenna Wherein the link antenna and the service antenna is a helical antenna formed in a spiral so as to generate a radio signal of circular polarization, the spiral link antenna and the service antenna is to generate a radio signal of circular polarization having the same direction of rotation It features.

Description

Home repeater having helical antenna

The present invention relates to a wireless communication repeater, and more particularly to a wireless communication indoor repeater having a helical antenna.

In general, in a mobile communication system such as PCS, an entire service area is divided into a plurality of service areas called cells, and each cell is provided with a base station constituting a radio link with a mobile communication terminal located in the cell. It is. However, due to the disturbance of a high-rise building or a high mountain, a shaded area where a signal from the base station cannot reach or weakens may be formed in the service area of the base station. In addition, such shaded areas are likely to occur inside or underground of large buildings.

The repeater amplifies the signal from the base station in the shaded area and provides it to the mobile communication terminal, and amplifies the signal from the mobile communication terminal and transmits the signal to the base station, thereby providing good communication service even in the shaded area. In particular, the indoor repeater is installed in the basement or basement of the building, so that a wireless link can be formed between the base station and the mobile communication terminal even in a building or basement where the signal from the base station cannot be sufficiently reached. For example, referring to FIG. 1, an indoor terminal 20 installed in a building transmits and receives a signal with a base station 10 through a link antenna 21, and performs mobile communication in a building through a service antenna 22. Send and receive signals with the terminal.

2 schematically illustrates a general structure of such an indoor terminal 20. Referring to FIG. 2, the indoor terminal 20 generally provides a link antenna 21 for transmitting and receiving a signal with a base station 10, a service antenna 22 for transmitting and receiving a signal with a mobile communication terminal, and a bidirectional signal. A repeater circuit 23 for amplifying without distortion is included. Here, as the link antenna 21 and the service antenna 22, a linear antenna such as a dipole antenna is mainly used.

However, in the case of the indoor repeater 20, when the link antenna 21 and the service antenna 22 are located together in the room, the signal is easily distorted and noise is generated due to the interference between the two antennas. Thus, in order to increase the isolation between the two antennas, the link antenna 21 is installed outside the building via, for example, a long cable 25, and the service antenna 22 and the repeater circuit 23 are connected to the building. It is installed inside. In this case, the service antenna 22 and the repeater circuit 23 may be mounted together in the case 24 of the indoor repeater 20. Since the link antenna 21 must be installed outside the building, the installation of the indoor repeater 20 in the building may not only add a separate installation cost burden but may also adversely affect the building aesthetics.

SUMMARY OF THE INVENTION An object of the present invention is to provide a repeater for wireless communication which can mount a link antenna and a service antenna together in a case of a repeater by increasing the isolation between the service antenna and the link antenna of the repeater.

A repeater according to an embodiment of the present invention, a link antenna for transmitting and receiving a signal with a base station, a service antenna for transmitting and receiving a signal with a mobile communication terminal, and a repeater circuit for amplifying bidirectional signals between the link antenna and the service antenna Wherein the link antenna and the service antenna is a helical antenna formed in a spiral so as to generate a radio signal of circular polarization, the spiral link antenna and the service antenna is to generate a radio signal of circular polarization having the same direction of rotation It features.

According to one embodiment, the link and the service antenna may each have a cylindrical dielectric substrate and an antenna element spirally wound around the cylindrical dielectric substrate.

For example, at least two antenna elements parallel to each other may be spirally wound around the cylindrical dielectric substrate.

For example, the antenna element may be wound at least once on the cylindrical dielectric substrate.

In addition, the repeater may further include a pupil-type reflector surrounding the link antenna and the service antenna, respectively.

The repeater may further include a case, and the link antenna, the service antenna, and the repeater circuit may be mounted together in the case.

According to one embodiment, both the link antenna and the service antenna can generate a radio signal of, for example, left circular polarization.

In another embodiment, both the link antenna and the service antenna may first generate a radio signal of circular polarization, for example.

Meanwhile, according to an embodiment, the link antenna and the service antenna may be arranged in the same direction.

In another embodiment, the link antenna and the service antenna may be arranged in opposite directions toward each other.

According to the repeater according to the present invention, since the link antenna and the service antenna of the repeater are formed to generate a circularly polarized radio signal having the same polarization, the isolation between the link antenna and the service antenna can be improved. As a result, even if the link antenna and the service antenna are located together inside the building, little interference occurs between the two antennas. Therefore, both the link antenna and the service antenna may be mounted in one case of the repeater. In this case, since there is no need to connect the link antenna to the repeater outdoors, no additional installation cost is added and it may not affect the aesthetics of the building.

Hereinafter, with reference to the accompanying drawings, the configuration and operation of the indoor repeater according to an embodiment of the present invention will be described in detail.

3 shows a schematic structure of a repeater 30 according to an embodiment of the present invention. Referring to FIG. 3, the repeater 30 according to an embodiment of the present invention includes a link antenna 31 for transmitting and receiving a signal with a base station, a service antenna 32 for transmitting and receiving a signal with a mobile communication terminal, and a link antenna. A repeater circuit 33 is disposed between the 31 and the service antenna 32 to amplify the signal in both directions. Here, the repeater circuit 33 may use a commonly known repeater circuit as it is. Although not shown, a circuit that performs an interference cancellation system (ICS) function may be further added to the repeater circuit 33.

According to one embodiment of the invention, the link antenna 31 and the service antenna 32 are circularly polarized antennas that generate radio signals of circular polarization. To this end, as shown in FIG. 3, a helical antenna wound in a spiral shape may be used as the link antenna 31 and the service antenna 32. 4 to 6 show various possible structures of the link antenna 31 in more detail. In the following, only the link antenna 31 is referred to for convenience, but the following description with reference to FIGS. 4 to 6 may be equally applied to the service antenna 32.

First, the schematic structure of the helical antenna used as the link antenna 31 can be understood through the development of FIG. Referring to FIG. 4, an antenna element 31b composed of a conductive thin film is attached to the dielectric substrate 31a in a diagonal direction. This can be achieved, for example, simply by printing the strip lines diagonally on a thin Teflon substrate. In this case, as shown in FIG. 4, the antenna element 31b may be printed in two parts on the dielectric substrate 31a. Then, when the dielectric substrate 31a is wound in a cylindrical shape, two divided parts are connected, and when the connected two parts are soldered, as shown in FIG. 3, a helical antenna in which the antenna element 31b is wound once is obtained. Can be. Alternatively, the antenna element 31b may be directly printed on the cylindrical dielectric substrate 31a.

In addition, according to another embodiment of the present invention, in order to increase the bandwidth of the link antenna 31 ', it is also possible to use two or more antenna elements. In FIG. 5A, two antenna elements 31b and 31c parallel to each other are attached to the dielectric substrate 31a in a diagonal direction. Even in this case, the two antenna elements 31b and 31c may be formed on the dielectric substrate 31a in two parts. Then, when the dielectric substrate 31a is wound in a cylindrical shape, two divided parts are connected, and when the two connected parts are soldered, as shown in FIG. 5B, two antenna elements 31b and 31c parallel to each other are formed. A helical antenna wound once in a spiral can be obtained. Depending on the bandwidth required, it is also possible to use three or more antenna elements.

Fig. 6 schematically shows the structure of a link antenna 31 ″ according to another embodiment of the present invention. In the link antenna 31 ″ shown in Fig. 6, the antenna element 31b is formed of a dielectric substrate (Fig. It is wound twice on 31a). This further enhances the circular polarization characteristic of the link antenna 31 ". At this time, since the frequency characteristic of the link antenna 31" depends only on the length of the antenna element 31b, the number of turns for the same frequency is increased. In order to increase, the diameter of the dielectric substrate 31a must be made smaller. Although FIG. 6 shows the antenna element 31b wound twice, a larger number of antenna elements 31b wound according to the embodiment may be used.

According to a preferred embodiment of the present invention, it is preferable that the aforementioned spiral link antenna 31 and the service antenna 32 are all wound in the same direction. Therefore, both the link antenna 31 and the service antenna 32 in the repeater 30 can generate radio signals of circular polarization having the same direction of rotation. For example, both the link antenna 31 and the service antenna 32 may generate a left circular circular polarization radio signal, or both may first generate a circular polarization radio signal. In the case of the repeater 30 according to the present invention having the link antenna 31 and the service antenna 32 generating the same circular polarization, the isolation between the two antennas can be greatly improved, the principle of which will be understood as follows. Can be.

A factor that greatly affects the isolation of indoor repeaters disposed in buildings is the so-called multi-path scattering caused by repeated reflection of signals by the walls inside the building. If the service antenna and the link antenna of the repeater are arranged together inside the building, the signal generated from the link antenna may be introduced into the service antenna by multipath scattering, and the signal generated from the service antenna may be transmitted to the link antenna as it is. Can be pulled in. The signal introduced into the antenna increases noise and becomes a factor that degrades the performance of the repeater. To avoid this problem, so far, link antennas are placed outside the building and only service antennas are placed inside the building.

On the other hand, the spiral helical antenna can transmit or receive only a circularly polarized signal that matches the rotational direction in which the antenna element is wound, and is hardly affected by the circularly polarized signal rotated in the opposite direction. As is already known, when a circularly polarized signal is reflected on a surface, the phase is reversed, so that the circularly polarized signal in the opposite direction is changed. For example, when a left circular polarized wave hits a wall and is reflected, it first changes to a circular polarized wave and proceeds.

Therefore, as in the present invention, when the link antenna 31 and the service antenna 32 are configured to transmit and receive only signals of the same circular polarization, the signal reflected from the wall in the building and the polarization direction is changed is transmitted to the link antenna 31 and the service. None of the antennas 32 will be affected. For example, when both the link antenna 31 and the service antenna 32 transmit and receive only a circularly polarized signal, the signal reflected and reflected on the wall of the building becomes a left circularly polarized wave, so that the link antenna 31 or the service It does not enter the antenna 32. On the other hand, the signal reflected twice on the wall of the building again becomes a circular polarization first, but during this time the strength of the signal is weakened, the noise caused by this can be sufficiently eliminated in the repeater circuit 33 in the repeater 30. As such, since the repeater 30 according to the present invention is less affected by multipath scattering, isolation between the link antenna 31 and the service antenna 32 may be improved. For example, the repeater 30 according to the present invention may have a degree of isolation of about 65 ~ 70dB.

As described above, since the isolation between the link antenna 31 and the service antenna 32 is high, according to the present invention, both the link antenna 31 and the service antenna 32 are mounted together in one case 34. It is possible to. Referring to FIG. 3, a link antenna 31, a service antenna 32, and a repeater circuit 33 are all disposed in a case 34 briefly indicated by a rectangular box. When both the link antenna 31 and the service antenna 32 are mounted in the case 34, the installation and movement of the repeater 30 is very convenient. That is, after installing the link antenna 31 outdoors, there is no need to connect with the repeater 30 through a separate cable. Therefore, a separate installation cost is not added, and it may not affect the aesthetics of the building.

In this way, when the link antenna 31 and the service antenna 32 are mounted together in the same case 34, in order to reduce the influence of the interference between the two antennas 31 and 32, as shown in FIG. The link antenna 31 and the service antenna 32 can be arranged in the opposite direction toward the far side. In this case, the link antenna 31 and the service antenna 32 face the opposite surfaces of the case 34, respectively. In addition, although not shown, the link antenna 31 and the service antenna 32 may be disposed in the same direction. In this case, the link antenna 31 and the service antenna 32 face the same side of the case 34, respectively. The two antennas 31 and 32 may be arranged so as not to face each other.

In addition, in order to further minimize mutual coupling between the link antenna 31 and the service antenna 32, as shown in FIG. 7, a pupil type surrounding the link antenna 31 and the service antenna 32, respectively, The reflector 35 may be further arranged. Although only the pupil reflector 35 for the link antenna 31 is shown in FIG. 7, the same pupil reflector 37 (see FIG. 3) can also be arranged for the service antenna 32. Referring to FIG. 7, a pupil-type reflector 35 formed of a conductive material such as metal is formed to have a cavity therein. For example, the pupil reflector 35 may be formed in a cylindrical shape with a bottom 36. The link antenna 31 is disposed above the bottom 36 of the pupil reflector 35 in the pupil of the pupil reflector 35. When the pupil reflector 35 is used, the directivity of the link antenna 31 and the service antenna 32 can be increased, and the possibility of mutual coupling between the two antennas 31 and 32 can be reduced.

To date, exemplary embodiments have been described and illustrated in the accompanying drawings in order to facilitate understanding of the present invention. However, it should be understood that such embodiments are merely illustrative of the invention and do not limit it. And it is to be understood that the invention is not limited to the details shown and described. This is because various other modifications may occur to those skilled in the art.

1 schematically illustrates a connection relationship between a general base station and an indoor repeater.

2 shows a schematic structure of a typical home repeater.

3 shows a schematic structure of an indoor repeater according to an embodiment of the present invention.

4 is an exploded view schematically illustrating a structure of the helical antenna illustrated in FIG. 3.

5A and 5B are exploded and perspective views schematically showing the structure of a helical antenna of a domestic repeater according to another embodiment of the present invention, respectively.

6 is a perspective view schematically showing a structure of a helical antenna of a domestic repeater according to another embodiment of the present invention.

7 is a perspective view schematically showing the structure of a helical antenna of a domestic repeater according to another embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

30 ..... repeater 31 ..... link antenna

31a..Dielectric substrates 32b, 31c .. Antenna elements

32 ..... service antenna 33 ..... repeater circuit

34 ..... case 35,37 ..... common reflector

36 ..... the bottom

Claims (10)

A repeater having a link antenna for transmitting and receiving signals with a base station, a service antenna for transmitting and receiving signals with a mobile communication terminal, and a repeater circuit for amplifying bidirectional signals between the link antenna and the service antenna, The link antenna and the service antenna are helical antennas formed spirally to generate a radio signal of circular polarization, And the spiral link antenna and the service antenna generate a circularly polarized radio signal having the same direction of rotation. The method of claim 1, And the link and service antennas each have a cylindrical dielectric substrate and an antenna element wound spirally around the cylindrical dielectric substrate. The method of claim 2, And at least two antenna elements parallel to each other are wound spirally on said cylindrical dielectric substrate. The method according to claim 2 or 3, And the antenna element is wound at least once on the cylindrical dielectric substrate. 4. The method according to any one of claims 1 to 3, And a pupil reflector surrounding each of the link antenna and the service antenna. 4. The method according to any one of claims 1 to 3, And a case, wherein the link antenna, the service antenna, and the repeater circuit are all mounted together in the case. 4. The method according to any one of claims 1 to 3, And the link antenna and the service antenna both generate radio signals of left circular polarization. 4. The method according to any one of claims 1 to 3, And both the link antenna and the service antenna first generate a radio signal of circular polarization. 4. The method according to any one of claims 1 to 3, And the link antenna and the service antenna are arranged in the same direction. 4. The method according to any one of claims 1 to 3, And the link antenna and the service antenna are arranged in opposite directions toward each other.

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