KR101048003B1 - Ring focus antenna for monopulse tracking and feeding horn - Google Patents

Abstract

The present invention is provided with a separate coaxial waveguide for monopulse tracking on the outside of the waveguide for transmitting data to extract a monopulse signal using mode coupling without affecting the transmission and reception data transmission line A ring focus antenna and a feed horn thereof.

An antenna of the present invention, the main reflector; Sub-reflective plate; A circular waveguide that transmits a signal for data transmission while the sub-reflection plate is attached to the front end of the main reflector while passing through the center of the main reflector, and surrounds the circular waveguide and receives a higher-order mode signal input from the dielectric horn. A feed horn comprising a coaxial waveguide for transmitting; And a mode coupler for receiving a higher order mode output of the coaxial waveguide to generate a difference pattern for monopulse tracking, thereby enabling monopulse tracking without affecting a transmission path for data transmission and reception.

Ring focus, monopulse, coaxial mode, mode coupler, antenna

Description

RING FOCUS ANTENNA FOR MONO-PULSE TRACKING AND FEED HORN OF THE ANTENNA}

The present invention relates to a parabolic antenna of a ring focus type, and more particularly, a coaxial waveguide for monopulse tracking is provided outside the waveguide for transmitting data, so as not to affect the transmission / reception data transmission line. The present invention relates to a ring focus antenna capable of extracting a monopulse signal using mode coupling and a feeding horn thereof.

Recently, in satellite communication systems, the output of satellites is increasing and terrestrial terminals are tending to be miniaturized. The concept of Vsat is a representative example.

As described above, in accordance with the trend toward miniaturization of terrestrial terminals, ring focus antennas are suitable for miniaturization and weight reduction, and are widely used in naval and civilian businesses as marine satellite antennas, vehicle-mounted satellite antennas, and aerial-mounted satellite antennas. The horn feeder for the monopulse applied to the tracking radar is configured by arranging several horn antennas, and then connecting each input terminal of the arranged horn antennas with a monopulse comparator so that the monopulse comparator needs a sum / difference pattern required for the tracking radar. Or in the case of a cylindrical horn antenna, a mode coupler is used to generate a sum / difference signal in a cylindrical waveguide.

Monopulse tracking using mode coupler has been used in satellite communication, but the ring focus method, which is used mainly in small antennas, is used because the higher-order mode is removed at the input stage of feeding horn. Step tracking has been mainly used.

The present invention has been proposed to enable monopulse tracking even in a ring focus method, and an object of the present invention is to place a coaxial waveguide at an outer portion of a ring focus feeding horn and use a sum pattern of a coaxial mode generated by the coaxial waveguide. And a ring focus antenna for monopulse tracking and a feed horn thereof capable of extracting a difference pattern.

In order to achieve the above object, the antenna of the present invention, the main reflector; Sub-reflective plate; A circular waveguide that transmits a signal for data transmission while the sub-reflection plate is attached to the front end of the main reflector while passing through the center of the main reflector, and surrounds the circular waveguide and receives a higher-order mode signal input from the dielectric horn. A feed horn comprising a coaxial waveguide transmitting; And a mode coupler for receiving a higher-order mode output of the coaxial waveguide and generating a difference pattern for monopulse tracking, thereby enabling monopulse tracking without affecting a transmission path for data transmission and reception.

The mode coupler is a 180-degree hybrid coupler (116-1 to 116) that synthesizes four high-order modes having opposite phases from four coaxial adapter ports P1 to P8 located opposite to each other in a coaxial waveguide. -4), a 180 degree hybrid coupler (116-5, 116-5) which combines the four synthesized signals back into two signals, and a delta (Δ) pattern or a ΔAZ and ΔEL pattern of RHCP and LHCP from the two signals. Is composed of a 90-degree hybrid coupler (116-7) for extracting the dielectric horn, and the dielectric horn has a long shape of a circular waveguide.

And the feed horn of the present invention to achieve the above object is a dielectric horn; A circular waveguide in which the dielectric horn is inserted to transmit a signal for transmitting data; A coaxial waveguide for transmitting a higher-order mode signal for monopulse tracking while surrounding the circular waveguide with a predetermined space; A polarizer connected to the rear side of the circular waveguide; An OMT coupled to the polarizer; A coaxial adapter formed at a rear side of the coaxial waveguide; And a mode coupler for receiving a higher order mode output of the coaxial waveguide through the coaxial adapter to generate a pattern for monopulse tracking, wherein the circular waveguide is a transmission path for transmitting data, and the coaxial waveguide is monopulse tracking. It becomes a transmission path for transmitting a higher-order mode signal for the data, and enables monopulse tracking without affecting the transmission path for data transmission and reception.

According to the present invention, a coaxial waveguide is separately positioned outside the ring focus feeding horn and a co-mode high order mode is generated using the coaxial mode to generate a mono pulse by synthesizing orthogonal modes of the high order mode. Accordingly, the present invention enables the use of a monopulse tracking scheme in a ring focus type parabola antenna, thereby greatly improving satellite tracking speed and accuracy.

In addition, according to the present invention, a coaxial waveguide is used in a ring focus type parabola antenna to generate a higher order mode for tracking without affecting a signal for data transmission and reception, and a sum and difference pattern is generated using a hybrid coupler to generate a monopulse. Tracking can be used. That is, the present invention does not affect the propagation path of the dielectric horn for data transmission and reception, and does not create a blocking area in the propagation transmission path of the main / sub reflector.

The technical problems achieved by the present invention and the practice of the present invention will be more clearly understood by the preferred embodiments of the present invention described below. The following examples are merely illustrative of the present invention and are not intended to limit the scope of the present invention.

1 is a schematic diagram showing the overall configuration of a ring focus antenna system for monopulse tracking according to the present invention.

In the monopulse tracking ring focus antenna 100 to which the present invention is applied, a feed horn 110 penetrates the center of the main reflector 102 and a dielectric horn is provided at the front end of the feed horn 110. The sub-reflective plate 104 is attached via the 106, and the rear end of the feed horn 110 has a structure in which the OMT 126 for separating the transmission signal and the reception signal is connected. The feed horn 110 includes a circular waveguide 122 for transmitting data and a coaxial waveguide 112 for generating a monopulse tracking signal while surrounding the circular waveguide, and the polarization waveguide 122 includes a polarizer. 124 and an Ortho-Mode Transducers 126 are connected, and the coaxial waveguide 112 is connected to the coaxial adapter 114 and the hybrid coupler 116.

2 is a schematic diagram illustrating a concept for applying monopulse tracking to a ring focus antenna according to the present invention, (a) is a front view, (b) is a side cross-sectional view, and (c) is a sub-reflection plate and a dielectric horn through A diagram illustrating a signal input path.

According to the present invention, the feed horn 110 for applying the monopulse tracking to the ring focus antenna 100 has a predetermined space with a central circular waveguide 122 for transmitting data, as shown in FIG. It has a double waveguide structure consisting of a coaxial waveguide 112 that surrounds the circular waveguide 122 and generates a difference pattern for monopulse tracking, and has a polarizer 124 and an OMT 126 on the rear surface of the circular waveguide 122. ) Is connected, and the coaxial adapter 114 and the hybrid coupler 116 are connected to the rear side of the coaxial waveguide 112 by a coaxial cable 115. In addition, the coaxial waveguide 112 and the front surface of the circular waveguide 122 are integrated with the dielectric horn 106 to which the reflecting plate 104 is attached, as shown in FIG. 2C, and integrated from the main reflector 102 to the sub-reflective plate side (focusing). ) Is reflected by the sub-reflection plate 104 to be input to the circular waveguide 122 and the coaxial waveguide 112 through the dielectric. Here, the dielectric horn 106 is an improved form of a long dielectric horn and a relatively long distance between the sub-reflection plate and the circular waveguide in order to use a coaxial mode coupler in the form of a short dielectric and a sub-reflection plate close to each other.

Referring to FIG. 2, signals of the coaxial waveguide 112 are output through the eight coaxial adapters 114, respectively, and transmitted to the hybrid coupler 116 through the coaxial cable 116, and the seven hybrid couplers 116 are connected to the coaxial waveguide 112. Left Handed Circular Polarization (RHCP) and Right Handed Circular Polarization (RHCP) Outputting a difference signal of the original wave), and outputting a ΔAZ (Azimuth: horizontal difference signal) or ΔEL (Elevation: vertical difference signal) pattern when using linear polarization. The OMT 126 separates the transmission signal and the reception signal so that transmission and reception can be performed through one circular waveguide 122.

 Figure 3 is a cutaway perspective view of a quarter of the feed horn for the ring focus antenna according to the present invention, Figure 4 is a schematic diagram showing the arrangement of the hybrid coupler according to the present invention, Figure 5 is a coaxial waveguide according to the present invention Is a diagram illustrating a coaxial adapter for connecting eight outputs in a coaxial line, and FIG. 6 illustrates a connection of a hybrid coupler for generating a difference pattern for monopulse tracking at eight outputs of a coaxial adapter according to the present invention. 7 is a diagram showing propagation of TE21 mode, which is a higher order mode in the mode coupler according to the present invention.

3 and 4, the feed horn 110 according to the present invention has a circular waveguide 122 for data transmission and a coaxial waveguide for generating a monopulse tracking signal while surrounding the circular waveguide 122. Reference numeral 112, a polarizer 124 connected to one end of the circular waveguide 122 and an OMT 126 connected to the polarizer 124 to separate a transmission / reception signal, for extracting a signal from the coaxial waveguide 112. The coaxial adapter 114 and the hybrid coupler 116 generates a difference pattern using a higher order mode signal of the coaxial waveguide input through the coaxial adapter 114. In addition, the coaxial waveguide 112 and the front surface of the circular waveguide 122 are coupled to the dielectric horn 106 to which the sub-reflection plate 104 is attached, so that a signal focused from the main reflection plate 102 to the sub-reflection plate side is received from the sub-reflection plate 104. It is reflected and input to the circular waveguide 122 and the coaxial waveguide 112 through the dielectric horn.

And the output of the coaxial waveguide is drawn through the eight coaxial adapter ports (P1 ~ P8) implemented in the position opposite to each other, as shown in Figure 5, the signal of the eight ports (P1 ~ P8) is shown in FIG. As shown in Fig. 6, eight high-order modes having opposite phases at intervals of 180 degrees are respectively synthesized into four signals using the hybrid couplers 116-1 to 116-4, and each of the four synthesized signals is combined. After synthesizing the two signals again using the hybrid couplers 116-5 and 116-6, the difference signal of the right handed circular polarization (RHCP) using the 90-degree hybrid coupler 116-7 is used. The difference signal (Δ) pattern or the ΔAZ (horizontal difference signal) pattern and the ΔEL (vertical difference signal) pattern of the Δ pattern and Left Handed Circular Polarization (LHCP) can be extracted.

Therefore, according to the present invention, the integrated signal is received from the reflector irrespective of the data transmission / reception path to perform a function such as a mode coupler so as not to degrade the transmission / reception performance of the data. As described above, the present invention not only improves the feeding portion of the ring focus antenna so that the monopulse tracking method can be used, but also reduces the transmission loss by separating paths as compared to the feeding horn for the monopulse tracking method of the satellite antenna using a mode coupler. have.

Next, the operation of the ring focus antenna according to the present invention configured as described above is as follows.

1. Data Transmission / Reception Path

Referring to FIG. 1 to FIG. 3, a radiation signal of a satellite integrated into the main reflector 102 is integrated, reflected by the sub reflector 104, and performs a subband reflector together. It enters the horn 106 and is transmitted to the circular waveguide 122. After the circular waveguide 122, the polar waveguide 124 of the square waveguide and the taper transition for interfacing to the polarizer 124, the signal passing through the polarizer 124 are each orthogonal two components Are separated to reach the OMT 126. The OMT 126 is capable of receiving signals that are orthogonal to each other to receive left handed circular polarization (LHCP) and right handed circular polarization (RHCP) or separate transmission and reception signals, respectively. To use it.

2. Mode Coupler for Ring Focus Antenna

Referring to FIGS. 1 to 6 along the transmission path of the mode coupler for the ring focus antenna, first, the radiation signal of the satellite integrated into the main reflector 102 is integrated, reflected by the sub-reflection 104, and the dielectric horn 106. Adjacent signals that do not flow into the N-channel are transmitted to the coaxial waveguide 112, and the propagation mode at this time is the transmission mode 'TE21' of the coaxial waveguide 112. It is output to eight coaxial adapter ports P1 to P8 facing each other, and eight high-order modes each having opposite phases are synthesized into four signals using hybrid couplers 116-1 to 116-4. Each of the four synthesized signals is once again synthesized into two signals using the 180 degree hybrid couplers 116-5 and 116-5, and then the difference of the RHCP (preferential circular polarization) using the 90 degree hybrid coupler 116-7. The signal? Pattern and the difference signal? Pattern of the LHCP (left circularly polarized wave) pattern or the? AZ (horizontal difference signal) pattern and the? EL (vertical difference signal) pattern are extracted. The difference signal pattern is directly applied to the monopulse tracker and is transmitted to the mono-pulse scan plate.

Although the present invention has been described with reference to one embodiment shown in the drawings, it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible therefrom.

1 is a schematic diagram showing an overall configuration of a ring focus antenna system for monopulse tracking according to the present invention;

2 is a schematic diagram illustrating a concept for applying monopulse tracking to a ring focus antenna in accordance with the present invention;

3 is a cutaway perspective view of a 1/4 of a feed horn for a ring focus antenna according to the present invention;

4 is a schematic diagram showing an arrangement of a hybrid coupler according to the present invention;

5 illustrates a coaxial adapter for connecting eight outputs in a coaxial waveguide with coaxial lines in accordance with the present invention;

6 is a diagram illustrating a connection of a hybrid coupler for generating a difference pattern signal for monopulse tracking at eight outputs of a coaxial adapter according to the present invention;

7 is a diagram illustrating propagation of a TE21 mode, which is a higher order mode in a mode coupler according to the present invention.

DESCRIPTION OF THE REFERENCE NUMERALS

100: ring focus antenna 102: main reflector

104: sub-reflective plate 106: dielectric horn

110: feed horn 112: coaxial waveguide

114: coaxial adapter 116: hybrid coupler

122: circular waveguide 124: polarizer

126: OMT

Claims (5)

Main reflector; Sub-reflective plate; A circular waveguide that transmits a signal for data transmission while the sub-reflection plate is attached to the front end of the main reflector while passing through the center of the main reflector, and surrounds the circular waveguide and receives a higher-order mode signal input from the dielectric horn. A feed horn comprising a coaxial waveguide for transmitting; And A mode coupler for receiving a higher order mode output of the coaxial waveguide and generating a difference pattern for monopulse tracking; Ring focus antenna for monopulse tracking that enables monopulse tracking without affecting the transmission path for data transmission and reception. The method of claim 1, wherein the mode coupler, 180-degree hybrid coupler (116-1 to 116-4), which combines eight high-order modes, each having opposite phases, into four signals from eight coaxial adapter ports (P1 to P8) located opposite each other in the coaxial waveguide, 180 degree hybrid couplers 116-5 and 116-5 for synthesizing the four synthesized signals into two signals again; From the two signals, the difference signal Δ pattern of the preferential circular polarization RHCP and the difference signal Δ pattern or the horizontal difference signal ΔAZ pattern and the vertical difference signal ΔEL pattern of the left turning circular polarization LHCP Ring focus antenna for tracking, characterized in that consisting of a 90-degree hybrid coupler (116-7) for extracting. The method of claim 1, wherein the dielectric horn, A ring focus antenna for monopulse tracking, wherein the circular waveguide has a long distance. Dielectric horns; A circular waveguide in which the dielectric horn is inserted to transmit a signal for transmitting data; A coaxial waveguide for transmitting a higher-order mode signal for monopulse tracking while surrounding the circular waveguide with a predetermined space; A polarizer connected to the rear side of the circular waveguide; An OMT coupled to the polarizer; A coaxial adapter formed at a rear side of the coaxial waveguide; And And a mode coupler for generating a pattern for monopulse tracking by receiving a higher order output of the coaxial waveguide through the coaxial adapter. The circular waveguide becomes a transmission path for transmitting data, and the coaxial waveguide becomes a transmission path for transmitting a higher-order mode signal for monopulse tracking to enable monopulse tracking without affecting the transmission path for data transmission and reception. Feeding horn of ring focus antenna for mono pulse tracking. The method of claim 4, wherein the coaxial waveguide transmits in TE21 mode, The mode coupler Four 180-degree hybrid couplers that combine eight high-order modes, each having opposite phases, into four signals from eight coaxial adapter ports (P1-P8) located opposite each other in a coaxial waveguide, and the four synthesized signals Two 180-degree hybrid couplers synthesized into two signals, and the difference signal (Δ) pattern of the preferred circular polarization (RHCP) and the difference signal (Δ) pattern of the left turning circular polarization (LHCP) pattern or horizontal from the two signals. A feed horn of a ring focus antenna for monopulse tracking, comprising a 90 degree hybrid coupler for extracting a difference signal (ΔAZ) pattern and a vertical difference signal (ΔEL) pattern.

Images