KR101874741B1 - Feed horn assembly of small parabolic antenna for multimode monopulse using tm01 mode coupler - Google Patents

Abstract

The present invention relates to a feed horn assembly for a small monopulse satellite communication antenna using a high-order mode coupler that meets a pattern standard and a cross polarization specification in a wide band by using a high-order mode coupler that generates a tracking signal using a TM01 mode signal. will be.
The feed horn assembly for a small monopulse satellite communication antenna using a higher order mode coupler according to the present invention includes a feeding horn 32 for receiving a signal and a signal for communication using a circular polarized signal outputted from the feeding horn 32 A circular waveguide 33 for simultaneously generating a TE11 mode and a tracking signal TM01 mode and a plurality of slots 34ba and an H plane TEE connection are formed in the circular waveguide 33, A high-order mode coupler 34 for coupling the tracking signal among the received signals, and an orthogonal mode polarizer 35 for separating the transmission signal and the reception signal from the transmission signal.

Description

TECHNICAL FIELD [0001] The present invention relates to a feeding horn assembly for a small monopulse satellite communication antenna using a high-order mode coupler,

The present invention relates to a feed horn assembly for a satellite communication antenna for tracking a multimode monopulse satellite, and more particularly, to a high-order mode coupler for generating a tracking signal using a TM01 mode signal, To a feed horn assembly for a small monopulse satellite communication antenna using a higher order mode coupler that meets the cross polarization specification.

The monopulse tracking system, derived from the radar system, allows the mobile platform to pinpoint and track the position of the target that it is aiming at.

A commonly used multi-horn monopulse tracking system places a plurality of horns on an antenna and uses them to extract a null pattern generated.

However, as described above, the multi-horn monopulse tracking system is difficult to satisfy the requirements of the antenna pattern (co-pol and cross-pol) due to the space constraints of mounting the plurality of horns on the antenna.

If a large base station antenna is applied to a large base station installed at a fixed position on the ground, a higher mode signal other than the basic mode signal is generated in a single horn assembly and a null pattern is extracted therefrom .

The large base station antenna uses a high-order mode coupler with many slots to receive a broadband beacon signal.

However, in a mobile platform such as a vehicle, a plurality of horns can not be installed as in the case of the large base station antenna, and there is also a problem in using a high-order mode coupler having a plurality of slots.

On the other hand, the following prior art document discloses a technique relating to a ring focus antenna for monopulse tracking and its feeding horn.

KR 10-2010-0114570 A

SUMMARY OF THE INVENTION The present invention has been developed to solve the above-mentioned problems, and it is an object of the present invention to provide a high-order mode coupler and antenna pattern (co-pol and cross-pol) And to provide a feed horn assembly for a small monopulse satellite communication antenna using a high-order mode coupler that can be satisfied at the same time.

It is another object of the present invention to provide a feed horn assembly for a small monopulse satellite communication antenna using a high-order mode coupler that satisfies pattern specifications and cross polarization specifications in a wide band at a high speed and high accuracy.

According to an aspect of the present invention, there is provided a feed horn assembly for a small monopulse satellite communication antenna using a high-order mode coupler, comprising: a feed horn for receiving a signal; And a H-plane TEE (H-plane TEE) connection is formed between a plurality of slots and a signal for generating a tracking signal (TM01 mode) A high-order mode coupler for coupling the signal and an orthogonal mode polarizer for separating the transmission signal and the reception signal in the transmission and reception signals.

The inner diameter of the circular waveguide is determined such that the communication signal TE11 mode and the tracking signal TM01 mode are generated from the signal received from the feed horn.

The high-order mode coupler is formed such that a pair of slots formed along the circumferential direction of the circular waveguide are symmetrically opposed to each other so that a signal input to the circular waveguide is introduced into the high-order mode coupler.

And the slot is formed in a rectangular shape having long sides along the circumferential direction of the circular waveguide.

A first port in which a signal is input from the circular waveguide and output to the orthogonal mode polarizer and in which the slot is formed; And a second port that is changed to a signal of a spherical waveguide (TE10 mode) and output to a spherical waveguide.

In the high-order mode coupler, the slot selects only a tracking signal from the communication signal (TE11 mode) and the tracking signal (TM01 mode), and extracts the tracking signal into a spherical waveguide using an H plane T connection .

The orthogonal mode polarizer is characterized by being a septum polarizer.

And a sub-reflector support for coupling the rear surface of the sub-reflector of the reflector antenna is further provided at a front end of the feed horn.

According to the feed horn assembly for a small monopulse satellite communication antenna using the high-order mode coupler of the present invention having the above configuration, a feed horn assembly suitable for a platform moving on the ground is realized, It is possible to provide a monopulse tracking system that is smaller and lighter than the monopulse tracking system used.

1A and 1B are a front perspective view and a rear perspective view showing a reflection plate type antenna apparatus to which a feed horn assembly for a small monopulse satellite communication antenna using a high-order mode coupler according to the present invention is applied.
FIGS. 2A and 2B are a perspective view and a sectional view of a feed horn assembly for a small monopulse satellite communication antenna using a high-order mode coupler according to the present invention;
FIGS. 3A through 3C are a perspective view, an exploded perspective view, and a cross-sectional view illustrating a high-order mode coupler applied to a feed horn assembly for a small monopulse satellite communication antenna using a high-order mode coupler according to the present invention;
4A to 4C are schematic views illustrating a signal synthesizing process using a feed horn assembly for a small monopulse satellite communication antenna using a high-order mode coupler according to the present invention.
5 is a graph illustrating a result of measuring a radiation pattern of a basic mode (sum pattern) and a higher-order mode (difference pattern) of a reflection plate type antenna device to which a feed horn assembly for a small monopulse satellite communication antenna using a high- FIG.

Hereinafter, a feed horn assembly for a small monopulse satellite communication antenna using a high-order mode coupler according to the present invention will be described in detail with reference to the accompanying drawings.

1A and 1B, a reflector antenna 1 according to the present invention includes a main reflector 10, a sub reflector 20, and a feed horn assembly 30, .

The reflector antenna 1 reflects the incident signal to the sub reflector 20 when a signal is incident on the main reflector 10 from the outside. At this time, the auxiliary reflector 20 allows the signal received from the main reflector 10 to enter the feed horn assembly 30. Here, the signal input to the feed horn assembly 30 may be a signal including at least one of a tracking signal and a communication signal.

In addition, the reflector antenna 1 satisfies the ITU-RR AP.8 radiation pattern and can generate a high-order mode signal.

2A and 2B show a feed horn assembly for a small monopulse satellite communication antenna using a high-order mode coupler according to the present invention.

The feed horn assembly 30 is formed by sequentially forming the auxiliary reflector support 31, the feed horn 32, the circular waveguide 33, the high-order mode coupler 34 and the Centameric wave retarder 35 from the sub- do.

The high-order mode coupler 34 may further include a rectangular waveguide (not shown).

The auxiliary reflector support 31 is coupled to the rear surface of the auxiliary reflector 20 so that the auxiliary reflector 20 is positioned at the front end of the feed horn assembly 30 and is opposed to the main reflector 10 .

The feeding horn 32 may be formed in the form of a wrinkled horn. The feeding horn 32 performs a mode conversion of a signal input from the auxiliary reflection plate 20 to the feed horn 32 to output a circularly polarized wave. That is, by converting the incident signal by the feed horn 32 into a signal suitable for each component of the feed hinge assembly 30 of the present invention, the physical characteristics (for example, The inner diameter of the waveguide, etc.), the signal is changed so that the characteristics of the signal such as the frequency, the wavelength, and the like change in a predetermined state.

The feeding horn 32 is formed by symmetrically forming the E plane and the H plane so that both the transmission band and the reception band have broadband characteristics satisfying the electrical performance such as the specifications of the antenna pattern For example, the feed horn 32 satisfies the characteristic of the X band (for example, 7 to 8 GHz) having a wide frequency band.

The circular waveguide 33 receives the mode-converted signal from the feed horn 32.

The inner diameter of the circular waveguide 33 can be defined such that a basic mode (TE11 mode) signal, which is a communication signal, and a high-order mode (TM01 mode) signal, which is a tracking signal, can occur at the same time.

The high-order mode coupler 34 receives the fundamental mode signal TE11 mode and the high-order mode signal TM01 mode generated in the circular waveguide 33.

The high-order mode coupler 34 has a plurality of slots 34ba and an H-plane TEE connection therein. The configuration of the high-order mode coupler 34 is shown in detail in FIGS. 3A to 3C. .

The high-order mode coupler 34 includes a housing 34a, a first port 34b connected to the circular waveguide 33 in the housing 34a, a second port 34c connected to the rectangular waveguide, A dummy port 34e is formed.

The housing 34a forms the outer shape of the high-order mode coupler 34. [ The inside of the housing 34a is formed as a hollow space. In addition, a plurality of ports 34b, 34c, and 34e through which signals transmitted and received through the reflector antenna 1 may enter and exit may be formed in the housing 34a.

The first port 34b is formed to be connected to the circular waveguide 33. A signal output from the circular waveguide 33 through the first port 34b is input into the high-order mode coupler 34. [

A plurality of slots 34ba are formed in the inner wall of the first port 34b. The slots 34ba are preferably symmetrical to each other. Since the coupling of the higher order mode signal TM01 mode is performed in the slot 34ba, the inner diameter of the circular waveguide 33 can be reduced more than the feed horn assembly using the TE21 mode as the higher order mode signal, The feed horn assembly 30 can be realized.

Here, the fact that the signal is coupled means that one of the signals generated in the circular waveguide 33 is selected and passed through the physical structure. For example, only the signal for tracking can be selected and passed through the slot 34ba among the signals for communication and the signals for tracking which are different in the operating mode.

The coupling may be variously performed depending on the shape of the slot 34ba. In the present invention, the slot 34ba may be formed in a rectangular shape having long sides along the circumferential direction of the first port 34b. Since the slot 34ba is formed in a rectangular shape, coupling suitable for the X band can be performed. The size of the slot 34ba may be determined experimentally or may be derived from a formula.

Also, a signal introduced into the first port 34b through the slot 34ba may be a passage that is transmitted to the inside of the housing 34a. A signal input to the first port 34b is transmitted to the left and right (refer to FIG. 3A and FIG. 3B) through the slot 34ba formed to face the first port 34b while being symmetrical with each other, 34a through the second port 34c formed on the opposite side of the first port 34b.

The second port 34c is connected to a spherical waveguide (not shown). (TM01 mode) signal of the same phase in the circular waveguide 33 may be coupled to the signal of the spherical waveguide (TE10 mode). And can be used for monopulse tracking by using the TE10 mode signal of the spherical waveguide changed from the higher order mode coupler 34. [ The signal (TE10 mode) passing through the rectangular plate pipe is transmitted to the LNA (Low Noise Amplifier) and can be used for monopulse tracking.

A signal is transmitted from the first port 34b to the second port 34c in the middle of the housing 34a and the through hole 34d is formed in the longitudinal direction of the circular waveguide 33. [ Accordingly, the high-order mode coupler 34 is formed with an H plane T connection.

A dummy port 34e is formed at one side of the housing 34a.

The septum polarizer 35 receives the basic mode signal TE11 mode from which the higher-order mode signal TM01 mode is removed from the higher-order mode coupler 34. [

The septum polarizer 35 is a type of orthomode transducer (OMT), and is a transmission signal for transmitting a signal transmitted / received from / to the outside to the outside and a reception signal Can be separated. Therefore, the septum polarizer 35 serves to prevent interference between a transmission signal and a reception signal in transmitting and receiving signals using one reflector antenna 1. [

The feeding horn assembly for a small monopulse satellite communication antenna using the high-order mode coupler according to the present invention having the above-described structure performs the signal combining process as shown in Figs. 4A to 4C.

4A, when the source horn is moved up and down, left and right, and a signal is applied to the feed horn assembly 30, the electric field of the TM01 mode signal generated inside the circular waveguide 33 becomes the circular Is formed radially in the direction of the edge from the center of the waveguide (33), and the magnetic field is formed only in the circumferential direction of the circular waveguide (33).

Accordingly, a high-order mode (TM01 mode) signal can be coupled using the slot 34ba formed in the first port 34b.

The high-order mode coupler 34 combines a high-order mode (TM01 mode) signal having an in-phase electromagnetic field induced by an H-plane mag- netic Tee and a TE10 mode signal of a spherical waveguide (See FIG. 4C).

4B shows an electric field of the high-order mode signal TM01 generated inside the circular waveguide 33 along the direction of the electric field of the source horn. From which the electric field in the vicinity of the slot 34ba is in phase when the source horn is horizontally polarized and moves in the horizontal axis and only when the source horn is vertically polarized and moves along the vertical axis, (34c).

As described above, according to the feed horn assembly for a small monopulse satellite communication antenna using the high-order mode coupler of the present invention, it is possible to satisfy the antenna radiation pattern standard as shown in FIG. 5, It is possible to provide a miniaturized and lightweight monopulse tracking antenna in which a null pattern of a higher-order mode signal (difference signal) is generated.

In addition, the present invention can provide a monopulse tracking system with faster and higher accuracy due to the feed horn assembly, which is also suitable for platforms moving on the ground.

1: reflector antenna
10: Main reflector
20:
30: feed horn assembly
31: auxiliary reflector assembly
32: Feeding horn
33: Circular waveguide
34: Higher order mode coupler
34a: Housing
34b:
34ba: Slot
34c: second port
34d: Through hole
34e: dummy port
35: Septum deflector

Claims (8)

A feeding horn for receiving a signal,
A circular waveguide for simultaneously generating a communication signal (TE11 mode) and a tracking signal (TM01 mode) using the circular polarization signal output from the feed horn,
A high-order mode coupler in which a plurality of slots and an H-plane TEE are formed and coupling the tracking signal among the signals received by the circular waveguide;
And an orthogonal mode polarizer for separating the transmission signal and the reception signal from the transmission / reception signal,
Wherein the high-order mode coupler is formed such that a pair of slots formed along a circumferential direction of the circular waveguide are symmetrically opposed to each other so that a signal input to the circular waveguide is introduced into the high-order mode coupler,
A first port in which a signal is input from the circular waveguide and output to the orthogonal mode polarizer and in which the slot is formed; (TE10 mode) of the spherical waveguide and outputting the signal to the spherical waveguide,
Wherein a through hole is formed in the middle of the housing to penetrate the housing in the longitudinal direction of the circular waveguide, the width of the through hole is larger than the outer diameter of the first port,
And the width direction of the second port is perpendicular to the longitudinal direction of the circular waveguide. The feed horn assembly for a small monopulse satellite communication antenna using the high order mode coupler. The method according to claim 1,
Wherein the inner diameter of the circular waveguide is determined such that the communication signal TE11 mode and the tracking signal TM01 mode are generated from the signal received from the feed horn. Feeding horn assembly. delete The method according to claim 1,
Wherein the slot is formed in a rectangular shape having long sides along the circumferential direction of the circular waveguide. delete The method according to claim 1,
In the higher order mode coupler,
The slot selects only the tracking signal from the communication signal (TE11 mode) and the tracking signal (TM01 mode)
Wherein the tracking signal is extracted as a spherical waveguide using a H plane T connection. ≪ RTI ID = 0.0 > 11. < / RTI > The method according to claim 1,
Wherein the orthogonal mode polarizer is a septum polarizer. ≪ RTI ID = 0.0 > 15. < / RTI > A feed horn assembly for a small monopulse satellite communication antenna using a high order mode coupler. The method according to claim 1,
Wherein the feed horn further comprises a sub reflector support coupled to a rear surface of a sub reflector of the reflector antenna at a front end of the feed horn.

Images