KR200366592Y1 - Flat antenna for receiving satellite broadcasting - Google Patents

Abstract

Disclosed is a plane antenna for satellite broadcasting reception. The disclosed antenna is a connector 60 which directly connects a feed line of patches and an LNB in a structure using a patch array of a microstrip pattern, and includes a center conductor 61 and an outer conductor 62 and an insulator between the center conductor and the outer conductor ( 63) is a coaxially coupled structure. The upper end of the center conductor 61 passes through the ground reflecting plate 40, the insulator 30, and the radiating substrate 10 in turn, and is soldered to be connected to each patch element 12 through a strip line on the radiating substrate 10. The lower end passes through the LNB case 51 and is connected by soldering to the connection hole 53 of the circuit board 52 embedded therein. The outer conductor 62 is in contact with the ground reflector 40 and the LNB case 51 while supporting the center conductor 61 so as to be grounded at an equipotential, and the insulator 63 insulates around the center conductor. When directly connected with an impedance-matched connector as described above, the antenna performance can be greatly improved by removing the conventional waveguide and increasing the number of patches by the area occupied by the waveguide.

Description

Flat antenna for receiving satellite broadcasting

The present invention relates to a planar antenna for satellite broadcasting reception. In particular, in a structure using a microstrip pattern patch array, an antenna is provided by directly connecting a feed line of patches and a low noise block (LNB) downconverter to a conductor. It's about improving performance.

Antennas for receiving satellite broadcasting are largely divided into parabolic antennas and planar antennas, and compared to parabola antennas that are widely used today, they are compact and easy to install, and can be installed indoors by receiving radio waves through glass windows. Planar antennas having a spotlight are attracting attention.

Microstrip planar antennas have been described in Korean Patent Publication No. 10-0313264 and Japanese Patent Laid-Open No. 2001-2002-0015428. Microstrip planar antennas pattern copper foil conductors stacked on one side of a thin insulator sheet in a microstrip shape to receive radio waves from multiple patches arranged and feed them with current signals collected through strip lines connecting each patch. The substrate is used.

Patches arranged on the radiating substrate are formed for linear polarization and circular polarization according to the polarization characteristics of radio waves to be received. Each polarized wave is also arranged to have a 90 ° phase along the polarization direction so that it can receive both vertical and horizontal polarizations of linearly polarized waves, or left and right circular polarizations and preferential circular polarizations of circular polarizations. Each patch is also installed with a polarizer to receive only a fragment wave in a specific direction (see Korean Utility Model Publication No. 20-0277743, Patent Registration No. 10-0429684).

For reference, Patent No. 10-0129088 discloses an LNB having vertical and horizontal polarization switching means.

On the other hand, the frequency band of satellite broadcasting radio waves is 11.7 ~ 12.7 GHz in Asia, for example, and the transmission loss is very large when the radio signal of this frequency band is directly transmitted from the antenna to the coaxial cable. Therefore, a low noise block down converter (hereinafter referred to as LNB) for amplifying a signal received by the antenna and converting the signal received by the antenna into an intermediate frequency band (1 GHz) is integrally combined.

In combining planar antennas and LNBs, conventionally, waveguides are mainly used to induce a patch signal collected on a feed line of the radiating substrate to the input probe of the LNB by performing secondary radiation at the end of the feed line.

In general, since the frequency of the satellite broadcast signal relayed from the broadcast satellite is weak, it is necessary to improve the performance of the antenna in order to receive the maximum signal. In addition, the signal received by the antenna must be able to transmit to the LNB without loss, and for this, impedance matching between the antenna and the LNB is very important.

As described above, impedance matching in the structure of secondary radiation through the waveguide is easy. However, waveguide, which is a kind of antenna, is a structural resonator whose size depends on frequency, so it occupies a large area on the radiating substrate, and the number of patches that can be arranged on the radiating substrate is reduced by that area. It has a problem of deterioration.

Furthermore, in many countries, the planar antenna for receiving the dual polarized wave has to have a larger area of the waveguide as well as the LNB in this case, so the above problem is further exacerbated, and the loss of approximately 3 dB is substantially increased. It is happening, and due to this, the planar antenna has not been practically used.

In order to solve this problem, a method of directly connecting an antenna and an LNB to a conductor without using a waveguide has been proposed in the related art through Korean Patent Laid-Open Publication No. 2002-0041702 and Utility Model Registration No. 20-0320089. However, when the conductor is used, impedance matching is very difficult, and in the past, it failed to be practical because it did not provide an appropriate solution for the impedance matching.

On the other hand, in order to improve the antenna performance, it is basically possible by increasing the effective area of the radiating substrate, but in this case, the opening surface of the planar antenna is larger than necessary and the price is greatly increased. It is not.

Accordingly, an object of the present invention is to provide a planar antenna in which antenna performance is improved by directly connecting an antenna and an LNB to a conductor without a waveguide, but the conductor is designed in an optimal structure for impedance matching between the antenna and the LNB.

It is also an object of the present invention to provide a planar antenna, which can further reduce the size of the LNB through the direct connection of the antenna and the LNB, and thus the price competitiveness is higher.

1 is a schematic cross-sectional view showing a laminated structure of a planar antenna for satellite broadcasting reception according to an embodiment of the present invention;

FIG. 2 is a detailed cross-sectional view illustrating a connection structure of the radiating substrate and the LNB shown in FIG. 1.

3 is an equivalent circuit diagram of a power supply circuit according to the connection structure shown in FIG.

Figure 4 is a schematic cross-sectional view showing a separate laminated structure of the planar antenna for satellite broadcasting according to another embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

10; 10a, 10b: Spinning board for vertical and horizontal patches

20; 20a, 20b: lens plate

30; 30a ~ 30d: dielectric

40: ground reflector

50: LNB

60; 60a, 60b: connector

70: polarizer

The planar antenna for receiving satellite broadcasting according to the present invention, which achieves the above object, includes at least one radiating substrate having a patch array having a microstrip pattern and a feed line connecting each patch, and spaced apart from the radiating substrate. A wave collection lens plate having an array of lens holes which overlap each other to focus the radio waves on each patch of the radiation substrate and block unwanted radiation from the remaining portions, and a radio wave which overlaps below the radiation substrate at intervals and passes through the radiation substrate. A ground reflector grounded to form a line with a feed line of the radiating substrate, the LNB coupled under the ground reflector to amplify and convert a signal, and penetrate the feeder line and the LNB directly through the ground reflector. A connector for electrical connection, the connector being impedance matched between the line of the radiating substrate and the LNB line. It is characterized by.

The connector is coaxially coupled with an insulator for insulation between the center conductor and the outer conductor, and one end of the center conductor is connected to the feed line on the radiating substrate and soldered through the ground reflecting plate and the radiating substrate. And the other end of the center conductor is soldered onto a circuit board embedded in the case of the LNB, the outer conductor of which is connected to the ground reflector and the LNB case at an equipotential, and the insulator is the center conductor, the ground reflector and the LNB case. It can be configured to insulate between.

Hereinafter, with reference to the accompanying drawings will be described a preferred embodiment of the present invention.

1 is a side schematic view of a planar antenna for linearly polarized light implemented to receive double polarized waves, that is, vertical and horizontal polarized waves, in accordance with an embodiment of the present invention. In the figure, the layers are shown spaced apart, but in reality they overlap in order to contact each other. In the figure, reference numerals 10a and 10b denote vertical and horizontal patch radiating substrates, 20a to 20b respectively correspond to lens plates corresponding to vertical and horizontal patch radiating substrates, 30 are ground reflecting plates, and 40a to 40d are radiating substrates 10a and 10b. ) And a dielectric interposed between each of the lens plates 20a and 20b and between the radiating substrate 10b and the ground reflecting plate 30, 50 is LNB, 60a and 60b are radiating substrates 10a, 10b and LNB 50. Is the connector of.

The spinnerets 10a and 10b for vertical and horizontal patches have a patch array and a feed line of microstrip patterns arranged by treating copper foil laminated on one surface of a thin sheet of insulating material by an etching method. The patch array and the feed line of the microstrip pattern are conventional, but have the connection holes 11a and 11b of the connector 50 at the feed point position of the feed line according to the present invention. The radiating substrates 10a and 10b are usually made of aluminum plates, and are opened only for the patch elements for the vertical and horizontal patches to collect and pass only the radio waves necessary for radiation, and block unnecessary radio waves to prevent unnecessary radiation. Improves side lobe characteristics.

The dielectrics 30a, 30b, 30c, and 30d interposed between the radiating substrates 10a and 10b, the lens plates 20a and 20b, and the ground reflection plate 40 are made of a synthetic resin foam such as styrofoam. Together with the role of insulator, it acts to shorten the propagation wavelength. Since the dielectrics 30a to 30d are larger than the dielectric constant of air 1, the propagation wavelength is shortened according to the dielectric constant, thereby reducing the thickness of the antenna. For example, the wavelength of satellite broadcasting waves should be spaced apart from the radiating substrate and the lens plate in the space of 2.5cm in air, but the placement interval can be narrowed by inserting the dielectric. Each dielectric made of styrofoam is suitable for 0.5 to 1.5mm as will be described later.

The ground reflector 40 is usually made of an aluminum plate, and is electrically grounded to form an image line with each microstrip of the radiating substrates 10a and 10b, and is not received by each patch of the radiating substrates 10a and 10b. Reflect the radio waves that have passed so that they can be received again.

The LNB 50 applied to the present invention is a conventional one capable of switching vertical and horizontal patch signals, and has two ports for inputting each patch signal. Each port is provided with connector 60a, 60b for signal connection.

2, the LNB 50 embeds the circuit board 52 in a case 51 which is usually made of an aluminum casting. The circuit board 52 is mounted with circuit elements for amplifying, filtering, and converting a signal fed from an antenna, and have a connection hole 53 instead of a conventional input probe.

According to the present invention, the impedance matched connectors 60a and 60b have a structure in which the center conductor 61 and the outer conductor 62 and the insulator 63 between the center conductor and the outer conductor are coaxially coupled. The center conductor 61 and the outer conductor 62 are made of copper, and the insulator 63 is made of Teflon resin. Here, the upper end of the center conductor 61 is soldered so as to pass through the ground reflecting plate 40, the insulator 30, and the radiating substrate 10 in order and to be connected to each patch element 12 through a strip line on the radiating substrate 10. The lower end is connected to the connection hole 53 of the circuit board 52 built therein through the LNB case 51 and soldered thereto. The outer conductor 62 is in contact with the ground reflector 40 and the LNB case 51 while supporting the center conductor 61 so as to be grounded at an equipotential, and the insulator 63 insulates around the center conductor.

The impedance matching condition of such a connector 50 is 50 [?] In the 12 GHz band, and satisfies the following condition.

Z is the impedance, ε is the dielectric constant of the insulator 63, D1 is the outer diameter of the center conductor 61, D2 is the inner diameter of the outer conductor 62.

3 shows an equivalent circuit of a power feeding circuit according to the present invention. Since the strip feeder line inside the antenna is only for transmitting signals, it should be prevented from radiating the current in the form of propagation from the feeder line (this is called unnecessary radiation). In the equivalent circuit of FIG. 3, the half-wave current i flows through the strip line 13 corresponding to the feed line of the radiating substrate, but the same magnitude of current flows in the opposite direction to the lower ground reflector or the image line 14 corresponding to ground. The unnecessary radiation can be prevented by adjusting the thickness of the above-mentioned dielectric material 30 interposed between the upper and lower lines so as to flow so that the electromagnetic field therebetween cancels. If the thickness of the dielectric 30 is too thick, the resonance is difficult and the current can flow in various directions, so that the loss due to the unnecessary radiation increases. Conversely, too narrow a gap increases the loss. As a result of the experiment, it was found that the sum of the quantum losses is minimized when the thickness of the dielectric material 30 of the styrofoam material in the range of 12 GHz is in the range of 0.5 to 1.5 mm.

In the above embodiment, by using only one of the two radiating substrates (10a, 10b) described above and the stacked structure associated with it, it is possible to implement a planar antenna for receiving a fragment wave, as well as the above-mentioned vertical and horizontal patch radiating substrate By arranging a circular or spherical patch instead of (10a, 10b), it can be implemented for the reception of circularly polarized left and primary circularly polarized signals.

Next, FIG. 4 shows another embodiment of the present invention by adding a polarizer 70 to the same structure as the previous embodiment, using the vertical and horizontal patch radiating substrates 10a and 10b. This is done to receive polarized wave.

The polarizer 70 is for converting the propagation of circular polarization into a linear polarization, a plurality of gratings 71 having a predetermined thickness and width of a metal plate at regular intervals, and an insulating support 72 for supporting the gratings, For example, it is easy to manufacture because it consists of a styrofoam material. Here, the spacing of the gratings 71 is designed to be λ / 4, λ / 8 or λ / 16 depending on the thickness and the width (depth).

As described through the above embodiments, the present invention connects the feed line and the LNB directly to a conductor in a planar antenna using a radiating substrate of a patch array having a feed line of a microstrip pattern, but has an optimal structure for impedance matching. By using the designed connector, the mutual transmission loss is minimized.

According to the present invention, it is possible to reduce the loss caused by the conventional waveguide and at the same time, it is possible to arrange more patches on the radiating substrate as much as the area occupied by the waveguide, thereby satisfying the maximum antenna performance, and using a radiating substrate of substantially the same size. In this case, an antenna gain of 3 dB or more can be increased as compared with the conventional case, and thus, a planar antenna can be used.

In addition, according to the present invention, since unnecessary space for resonance in the LNB is eliminated, the planar antenna volume can be further reduced by miniaturization and cost reduction of the LNB, so that the performance can be improved but the price can be lowered to further increase the competitiveness.

Claims (8)

At least one radiating substrate having a patch array of microstrip patterns and a feeding line connecting each patch, and overlapping one side of the radiating substrate at a distance from the radiating substrate to focus satellite radio waves and passing them through each patch of the radiating substrate A wave collection lens plate having an array of lens holes to block unwanted radiation in the remaining portion, and the feed line and the line of the radiation substrate are reflected while overlapping the other side of the radiation substrate and reflecting the radio waves passing through the radiation substrate. A ground reflecting plate grounded to achieve a grounding, an LNB installed on the opposite side of the ground reflecting plate for amplifying and converting a signal, and a connector for directly connecting the feed line of the radiating substrate and the LNB through the ground reflecting plate; Satellite broadcasting reception, characterized in that the impedance match between the feed line and the LNB line of the radiating substrate Flat antenna. The feeder line of claim 1, wherein the connector is coaxially coupled with an insulator for insulation between the center conductor and the outer conductor, and one end of the center conductor penetrates the ground reflecting plate and the radiating substrate. And the other end of the center conductor are soldered on a circuit board embedded in the case of the LNB, and the outer conductor connects the ground reflector and the LNB case at an equipotential, and the insulator is connected to the center conductor. Planar antenna for receiving satellite broadcasting, characterized in that it is insulated between the ground reflector and the LNB case. The connector according to claim 2, wherein the impedance for the required matching is Z, the outer diameter of the center conductor is D1, the inner diameter of the outer conductor is D2, and the medium dielectric constant between the ground reflector and the radiating substrate is?. Impedance of A planar antenna for satellite broadcast reception, characterized in that the conditions of satisfying. The satellite broadcasting reception apparatus according to claim 1, wherein the at least one radiating substrate is provided with two 90-degree phases arranged to simultaneously receive vertical and horizontal polarizations of linearly polarized waves or left and primary circular polarizations of circular polarizations. Flat antenna. The planar antenna of claim 1, further comprising a dielectric inserted between the radiating substrate and the lens plate and between the radiating substrate and the ground conductor plate. The planar antenna for satellite broadcasting reception according to claim 5, wherein the thickness of the dielectric is in a range of 0.5 to 1.5 mm. The planar antenna for satellite broadcasting reception according to claim 1, wherein the radiating substrate is provided for linear polarization, and a polarizer for converting circular polarization into linear polarization on the lens plate. The plane antenna for satellite broadcasting reception according to claim 7, wherein the polarizer comprises a plurality of grids arranged at a constant width, thickness, and a predetermined interval and an insulating support supporting the grids.