KR960013661B1 - Receiver and converter for use in a satellite antenna - Google Patents

Abstract

a LNB(31) including a main substrate(33) making the frequency down to some value; a feedhorn(32) which is mounted on one side of the LNB(31) to receive the signal from a satellite; a conducting plate(34) mounted perpendicularly to the center of the feedhorn(32); a first or a forth transmission line(51-54) to connect the conducting plate(34) with a main circuit of the main substrate; and a switching part(60) to select the specific signal by connecting with the transmission line.

Description

Receiver for Satellite Antenna with Multiple Polarization Reception

1 and 2 are structural diagrams showing several examples of a conventional device for linearly polarized wave reception.

3 (a) and 3 (b) are structural diagrams showing a device for converting a conventional circular polarization into a linear polarization.

Figure 4 is a partially cutaway perspective view showing a receiver converter for a multi-polarization satellite antenna according to the present invention.

5 is a cross-sectional view of the main portion of FIG.

6 is a circuit diagram of a receiver converter for a multi-polarization satellite antenna according to the present invention.

* Explanation of symbols for main parts of the drawings

30: Receive converter 31: LNB

32: waveguide 33: main board

34: conductive plate 35, 36: first and second connection lines

51-54: first to fourth transmission lines 60: switching unit

61-64: first to fourth switches

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiver for satellite antenna, and more particularly, to a receiver for satellite antenna capable of receiving multiple satellite signals or information having different polarization characteristics and simplifying a circuit connection structure.

A general satellite antenna focuses radio waves emitted from geostationary satellites and transmits them through a cable to an information receiver or a TV receiver. These satellite antennas are provided with a receiving converter which converts the converged frequency of about 11-12 GHz to about 1 GHz, converts it into a frequency band usable by an information receiving apparatus or a TV receiver, and transmits the received signal. The receiving converter receives a satellite signal largely. A low noise blockdown converter (hereinafter abbreviated as LNB) is provided with a waveguide (Feedhorn) and a main circuit section for bringing down a received frequency.

In general, radio waves emitted from stationary satellites do not interfere with each other according to their frequency bands and polarization characteristics or vary from region to region, and the polarization characteristics are classified into linear polarization and circular polarization. Linear polarization includes horizontal polarization in addition to vertical polarization, and circular polarization includes left circular polarization and first circular polarization. Therefore, the receiving converter is provided with components for receiving a desired signal from satellite signals having different polarization characteristics as described above.

First, FIG. 1 shows a receiver converter for receiving linear waves, that is, vertical and horizontal polarized waves, between an O.M.T. between a circular waveguide 1 for receiving satellite signals and two LNBs 2,3. (Ortho-mode transducer: hereinafter abbreviated as OMT) (4) is provided. The OMT (4) is capable of receiving vertical and horizontal polarized waves by separating the signals received from the circular waveguide (1) into vertical and horizontal components, respectively, and then transferring the output terminals to two LNBs (2) (3). It is done. However, since the conventional method uses two expensive LNBs, there is a disadvantage in that the price of the product increases by that, and the OMT and the LNB configured additionally reduce the effective reception area of the antenna by the space occupied by them.

2 is another example of the related art, in which a plunger 14 is rotatably installed by a servo motor 13 between a circular waveguide 11 and an LNB 12, and a rotator probe is provided in the plunger 14. (15) is installed. Therefore, the mechanical rotation of the servomotor 13 changes the direction of the resonance probe 15 installed in the plunger 14 so that vertical and horizontal polarized waves can be selected from the satellite signals received by the circular waveguide 11. . However, the above method also increases the price of the product because of the addition of a mechanical device, relatively mechanical device has a disadvantage of high failure rate and short life.

There is also a configuration in which a magnetic plunger is installed in a circular waveguide in a manner similar to the above example. This allows the radio waves to be rotated by the magnetic field generated by adjusting the magnitude of the current flowing in the coil wound on the ferrite core, thereby allowing selective selection of vertical or horizontal polarization by coupling to the resonant probe. However, in this method, the rotation angle of the radio wave is determined according to the amount of current flowing through the coil in the winding of the ferrite core, but it is also difficult to adjust according to the frequency of the received signal, and thus the price of the product is expensive.

The three methods described above enable the selective reception of vertical and horizontal polarized waves, but have a common problem that cannot be selected in the case of circularly polarized files. Therefore, in order to be able to receive a circular wave, as shown in FIG. 3 (a) and (b), an apparatus for converting a circular polarization into a linearly polarized wave has been developed. That is, as shown in FIG. 3 (a) and (b), the resonant pro part 23 is provided in the vertical direction at the lower center of the center of the spherical waveguide 22 provided in the LNB 21. Teflon slab 24 for converting circular polarization into linear polarization is provided in front of the resonant probe 23. Therefore, when the polarization characteristic of the satellite signal is left circularly polarized, as shown in FIG. 3 (a), the teflon slab 24 in the rectangular waveguide 22 is inclined from the upper left to the lower right, and the polarization characteristic of the satellite signal takes precedence. In the case of circular polarization, as shown in FIG. 3 (b), when the teflon slab 24 is inclined from the lower left to the upper right, the circular polarization is converted into a vertical or horizontal linear polarization to enable reception.

However, the above-described method has a disadvantage in that components are increased because Teflon slabs are additionally installed in order to select circular polarizations, and this method also has a problem in that linear polarizations in addition to two circular polarizations cannot be selected.

The present invention is to solve the conventional problems as described above, an object of the present invention is to provide a receiver for a satellite antenna capable of multiple polarization reception that can be received by selecting a circular polarization as well as a linear polarization.

Another object of the present invention is to provide a receiver for a satellite antenna capable of multi-polarization reception that is easy to manufacture and lower the manufacturing cost by making the device for receiving the multi-polarization in a simple structure.

The above object is a receiver antenna for a satellite antenna for receiving and transmitting a radio wave of a satellite signal to an information receiving apparatus, comprising: an LNB having a main board formed therein with a main circuit having a main circuit for reducing a frequency to a predetermined value; A waveguide provided at one side for receiving a signal from a satellite, installed at a right angle with respect to a center direction in the waveguide, and for connecting a conductive plate having a predetermined area to the main circuit of the LNB, respectively; The first to fourth transmission lines having different lengths and the conductive plates and the first to fourth transmission lines may be selectively connected to one or more transmission lines so as to select linear polarization and circular polarization. Receiving for satellite antenna capable of multiple polarization reception, characterized in that it comprises a switching unit for selection It can be achieved by butter.

In addition, the length of the first and third transmission lines is preferably formed to be longer by λg / 4 than the second and fourth transmission lines, and the conductive plate is provided on the main board extending to the inside of the waveguide. It is preferable to connect the first to fourth transmission lines with two connection lines, and the switching unit is provided between the first and second connection lines of the conductive plate and the first to fourth transmission lines, respectively, to be turned on according to the voltage applied to the gate terminal. It is preferable to set it as the 1st-4th switch turned off.

Hereinafter, a receiver for a satellite antenna according to the present invention will be described in detail with the accompanying drawings. 4 shows a receiver for a satellite antenna capable of multiple polarization reception according to the present invention, and the receiver converter 30 is mainly composed of an LNB 31 and a circular waveguide 32, and is circular from the inside of the LNB 31. A main board 33 having a circuit for lowering a reception frequency is provided over the inside of the waveguide 32, and a square conductive plate having an area of a predetermined size is provided on the main board 33 positioned inside the circular waveguide 32. 34 is located at right angles to the central direction. 4 and 5, the first and second connection lines 35 and 36 extending from one side of the conductive plate 34 are connected to the circuit portion of the main board 33. Therefore, since the circuits of the conductive plate 34 and the main substrate 33 are connected in the plane of the same substrate, their connection structure becomes very simple.

6 is a circuit diagram of a receiver for a satellite antenna capable of multiple polarization reception according to the present invention. The LNB 31 is a low noise amplifier 41 and a bandpass filter for removing unwanted noise from a received frequency. 42, a mixer 44 for synthesizing the frequency passed through the bandpass filter 42 and the radio waves from the oscillator 43, and an intermediate frequency amplifier 45 for amplifying the frequency down through the mixer 44. And a band cut filter 46 for removing noise. In addition, the conductive plate 34 provided on the main substrate 33 in the circular waveguide 32 is connected to the low noise amplifier 41 of the LNB 31, and between the conductive plate 34 and the low noise amplifier 41. The transmission line and the switching unit 60 are provided. First and second transmission lines 51 and 52 having different lengths are formed between the first connection line 35 and the low noise amplifier 41 of the conductive plate 34, and the length of the first transmission line 51 is 2 longer than the transmission line 52 by? G / 4.

Similarly, third and fourth transmission lines 53 and 54 having different lengths are formed between the second connection line 36 of the conductive plate 34 and the low noise amplifier 41, but the oddity of the third transmission line 53 is increased. It is formed by? G / 4 longer than the 42nd transmission line 54. Further, the first and second switches 61 and 64 are provided between the first and second connection lines 35 and 36 and the first to fourth transmission lines 51 and 54 to provide the first and second switches. The connection lines 35 and 36 and the first through fourth transmission lines 51 and 54 are selectively connected to select one polarized wave among multiple polarized waves. The first to fourth switches 61 and 64 perform a switching action of being turned on or off according to the voltage applied to the gate terminal. For example, the first to fourth switches 61 and 64 are turned off when no voltage is applied to the gate terminal. When the voltage applied to the gate terminal is greater than the pinchoff voltage, it is turned on.

Such operation of the present invention will be described with reference to the following table and FIG.

The satellite signal received by the conductive plate 34 provided in the circular waveguide 32 is transmitted to the circuit of the LNB 31 through the switching unit 60 and the transmission line. In this case, the first and second connection lines 35 and 36 and the first to fourth transmission lines 51 and 54 of the conductive plate 34 are selectively connected according to the on / off state of the switching unit 60. And shorted, one of the multiple polarizations is selected. That is, in order to receive the vertical polarization as shown in the above table, the first, third, and fourth switches 61, 63, 64 of the first to fourth switches 61-64 are turned off, and the second When the switch 62 is turned on, the conductive plate 34 and the second transmission line 52 are connected to receive only the vertical polarized wave among the multiple polarized waves. When the horizontal polarization is to be received in this manner, the first to third switches 61, 62 and 63 of the first to fourth switches 61 to 64 are turned off and the fourth switch 64 is turned off. When turned on, the conductive plate 34 and the fourth transmission line 54 is connected to receive only the horizontal polarization of the multiple polarization. In addition, when the left circular circular polarization is to be received, the second and third switches 62 and 63 of the first to fourth switches 61 to 64 are turned off, and the first and fourth switches 61 ( When 64 is turned on, the conductive plate 34 and the first transmission line 51 are connected to each other, and at the same time, the conductive plate 34 and the fourth transmission line 54 are also connected to receive only the left line circular polarization among the multiple polarizations. do. First, when the circular polarization is to be received, the first and second switches 61 and 64 of the first to fourth switches 61 and 64 are turned off, and the second and third switches 62 and 62 ( When 63 is turned on, the conductive plate 34 and the second transmission line 52 are connected, and at the same time, the conductive plate 34 and the third transmission line 53 are also connected to receive only the first circular polarization among the multiple polarizations. Will be.

As described above, according to the receiver for a satellite antenna according to the present invention, one or two transmission lines of the first to fourth transmission lines connected to the multiple polarized wave received by the conductive plate provided on the main board in the circular waveguide by the switching unit By passing through the LNB through the circuit it is possible to receive the selected specific polarization of the multi-polarization, thereby increasing the functionality of the product is not only convenient to use, but also a separate device that has been added for the conventional reception of the multi-polarization There is no need for economics. In addition, the device of the present invention is an industrially useful invention that the circuit of the conductive plate and the main board is connected on the plane of the same substrate, so that the connection structure is simple, and the manufacturing is easy and the price can be provided at a lower cost.

Claims (4)

In a receiver for a satellite antenna for transmitting a radio wave of a satellite signal to an information receiver, an LNB 31 having a main board 33 having a main circuit for lowering a frequency to a predetermined value therein, and A waveguide 32 provided at one side for receiving a signal from a satellite, a conductive plate 34 having a predetermined area as being installed at right angles to the center direction in the waveguide 32, and the conductive plate 34 ) Are connected to the main circuit of the main board, respectively, so that the first to fourth transmission lines 51 to 54 having different lengths to select the linearly and circularly polarized waves, and the conductive plates and the first to And a switching unit 60 for selecting a specific polarized signal by being provided between the fourth transmission line and selectively connected to one or more transmission lines. Nayong reception converter. The satellite antenna of claim 1, wherein the lengths of the first and third transmission lines 51 and 53 are longer than the lengths of the second and fourth transmission lines 52 and 54 by λg / 4. Receive converter. The first and fourth transmission lines 51 of claim 2, wherein the conductive plate 34 is provided on the main board 33 extending to the inside of the waveguide and is connected to the first and second connection lines 35 and 36. Receive converter for satellite antenna capable of multiple polarization reception connected to -54. The switching unit 60 is provided between the first and third connection lines 35 and 36 and the first to fourth transmission lines 51 and 54 of the conductive plate 34, respectively. And a first to fourth switches (61) to (64) which are turned on and off in accordance with a voltage applied to a gate terminal.