Ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed source and feed source system

Abstract

The invention provides an ultra-wideband multimode self-tracking coaxial four-ridge horn feed source and a feed source system, and relates to the field of satellite communication, satellite measurement and control and electronic reconnaissance. The feed source comprises a coaxial horn, four same ridge pieces are arranged at the positions of 0 degree, 90 degrees, 180 degrees and 270 degrees on the inner wall of an outer conductor of the coaxial horn in the circumferential direction, a probe perpendicular to the axis direction of the horn is arranged at the tail of each ridge piece, and a reflection cavity is formed between each probe and a bottom plate at the tail of the coaxial horn. The coaxial horn inner conductor is of a conical structure with the radial height gradually reduced, and the coaxial horn inner conductor extends out of the coaxial horn mouth surface. According to the invention, a dual-mode sharing technology combining a TE11 mode and a TEM mode in a coaxial waveguide is adopted, and a communication function and a self-tracking function can be realized at the same time in a quintuple-frequency bandwidth. The ultra-wideband monopulse self-tracking feed source system is excellent in sum and difference mode performance, compact in structure and wide in application scene, and is a novel and easy-to-implement ultra-wideband monopulse self-tracking feed source system.

Description

Technical Field

[0001] The present invention relates to the technical fields of satellite communication, satellite TT&C, and electronic reconnaissance, and specifically provides an ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed and a feed system. Background Art

[0002] With the rapid development of satellite communication technology, the performance requirements for reflector antenna systems are increasing day by day. To meet the needs of satellite communication, reflector antennas are developing towards the multi-functional direction of wide bandwidth, multi-frequency bands, and compatibility between tracking and communication. Especially in the field of mobile communication, satellite / vehicle mobile communication terminals are playing an irreplaceable role, which requires reflector antennas to have both communication functions and high-precision tracking functions, and has become one of the inevitable trends in the development of satellite communication antenna technology.

[0003] Currently, there are mainly three ways for antennas to track targets: manual tracking, program tracking, and automatic tracking. Automatic tracking is widely used due to its good real-time performance. According to different tracking principles, automatic tracking can be further divided into three systems: step tracking, conical scanning tracking, and monopulse tracking. Among them, monopulse tracking is the most commonly used high-precision tracking method at present.

[0004] In an ultra-wideband monopulse tracking reflector antenna system, an ultra-wideband high-performance monopulse tracking feed system is one of the core components. According to its working principle and structural characteristics, monopulse tracking feeds can be mainly divided into multi-channel tracking feeds and multi-mode tracking feeds. Among them, multi-channel tracking feeds mainly include four-horn feeds and five-horn feeds. Their working principle is simple, but they have disadvantages such as large blockage of the reflector antenna and large sum-difference contradictions. Multi-mode tracking feeds use multiple specific modes in the waveguide to achieve sum-difference mode reception / radiation, mainly including circular waveguide TE 11 / TM 01 dual mode, circular waveguide TE 11 / TE 21 dual mode, coaxial waveguide TE 11 / TEM dual mode, and coaxial waveguide TE 11 / TE 21 dual mode, etc. This type of feed has the advantages of simple structure, high antenna aperture efficiency, and high difference gain. However, due to the limited working bandwidth of the sum mode TE 11 mode, it cannot meet the requirements of ultra-wideband operation. Summary of the Invention

[0005] The purpose of the present invention is to avoid the problems that appear in the above technical background, and provide an ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed and a feed system. The present invention has the characteristics of simple structure, wide working frequency band, small reflection loss, high irradiation efficiency of the reflector antenna, high difference gain, and large null depth of the difference pattern.

[0006] The technical solution adopted by the present invention is as follows:

[0007] An ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed includes a coaxial horn, and the coaxial horn includes a coaxial horn outer conductor and a coaxial horn inner conductor nested together; the inner wall curve of the coaxial horn outer conductor is divided into two sections from back to front, the first section is a straight section with a constant radial height, and the second section is a spline function curve section; the contour curve of the coaxial horn inner conductor is divided into two sections from back to front, the first section is a straight section with a constant radial height, and the second section is a spline function curve section, wherein the radius of the coaxial horn inner conductor in the spline function curve section gradually decreases to form a conical structure; on the inner wall of the coaxial horn outer conductor, identical ridge fins are provided at 0°, 90°, 180°, and 270° in the circumferential direction, and the ridge curve of the ridge fin is divided into three sections from back to front, the first section is a straight section with a constant radial height, the second section is a linearly expanding section with a gradually increasing radial height, and the third section is a spline function curve section; a probe perpendicular to the axis direction of the coaxial horn is provided at the tail of each ridge fin, and the probe passes through the coaxial horn outer conductor and the ridge fin in an insulating manner and then inserts into the coaxial horn inner conductor; the front end of the coaxial horn inner conductor extends out of the coaxial horn aperture plane.

[0008] Further, the length of the coaxial horn inner conductor extending out of the coaxial horn aperture plane is 0.05 -0.1 , where is the wavelength corresponding to the lowest frequency.

[0009] Further, the maximum radius of the coaxial horn inner conductor does not exceed 0.1 , where is the wavelength corresponding to the lowest frequency.

[0010] Further, the radius of the vertex of the head of the coaxial horn inner conductor is 0.3 - 0.7 mm.

[0011] Further, a bottom plate is provided at the tail of the coaxial horn, and a reflection cavity is provided between the probe and the bottom plate, and the reflection cavity is in a circular cylindrical structure.

[0012] Further, a choke groove is further provided at the head of the coaxial horn outer conductor.

[0013] Further, the number of the choke grooves is 2.

[0014] In addition, the present invention further provides an ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed system, including the ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed described in any one of the above, and further including a sum-difference beam synthesis network; the four probes of the ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed are all connected to the sum-difference beam synthesis network through SMA sockets;

[0015] The sum-difference beam synthesis network includes two 180° bridges, a power divider, and a 90° bridge. The sum beam signal is synthesized via two 180° bridges and a 90° bridge, and the difference beam signal is synthesized via two 180° bridges and a power divider.

[0016] When synthesizing the sum beam signal, a pair of horizontally placed probes form a horizontally polarized coaxial TE 11 mode through the 180° channel of the 180° bridge, and a pair of vertically placed probes form a vertically polarized coaxial TE 11 mode through the 180° channel of the 180° bridge. The horizontally polarized TE 11 mode and the vertically polarized TE 11 mode are then synthesized into a circularly polarized TE 11 mode through the 90° bridge. The two ports of the 90° bridge respectively output a left-handed circularly polarized TE 11 mode signal and a right-handed circularly polarized TE 11 mode signal.

[0017] When synthesizing the difference beam signal, two sets of horizontally and vertically placed probes respectively form two synthesized signals through the 0° channels of two 180° bridges, and the two synthesized signals are then synthesized into a coaxial TEM mode signal through the power divider.

[0018] The present invention has the following advantages compared with the background technology:

[0019] 1. The present invention proposes an innovative solution for a coaxial feed system with an ultra-wideband monopulse self-tracking function. The present invention adopts a dual-mode sharing technology combining coaxial TE 11 mode / TEM mode, and simultaneously realizes communication function and self-tracking function within a bandwidth of 5 times the frequency. Among them, the TE 11 mode is the communication mode (sum mode), and the TEM mode is the tracking mode (difference mode). By setting a ridge structure on the outer conductor of the coaxial horn, the working bandwidth of the TE 11 mode is significantly extended. At the same time, as the main mode of the coaxial waveguide, the TEM mode has non-dispersive characteristics and inherently has ultra-wideband characteristics.

[0020] 2. The present invention significantly expands the working bandwidth of the coaxial horn feed, expanding the bandwidth of the coaxial horn feed to 5 times the frequency. The present invention effectively reduces the cut-off frequency of the TE 11 mode in the coaxial waveguide by setting a ridge structure on the inner wall of the outer conductor of the coaxial horn, while the cut-off frequency of the higher-order mode TE 31 mode remains almost unchanged. Therefore, the single-mode working bandwidth of the TE 11 mode in the coaxial waveguide is significantly expanded.

[0021] 3. In the present invention, both the sum mode and the difference mode of the feed have good transmission characteristics and radiation characteristics. The inner wall curve of the coaxial outer conductor, the ridge curve of the ridge piece, and the contour curve of the coaxial inner conductor all include spline function curves, which are formed by fitting multiple discrete points and provide a large degree of design freedom. Through sufficient optimization of the coordinates of the discrete points of the spline function curve, the sum mode and the difference mode of the coaxial four-ridge horn feed can have good transmission characteristics and radiation characteristics. In addition, by designing the coaxial horn inner conductor as a tapered structure and extending it out of the coaxial horn aperture plane, the transmission characteristics and radiation characteristics of the difference mode can be further improved, thereby achieving an overall performance improvement.

[0022] 4. The present invention has a wide range of application scenarios. The present invention can not only be used as a high-performance broadband feed, but also meet the requirements of broadband monopulse self-tracking. Further, the working frequency band of the feed covering five octaves can simultaneously cover multiple frequency bands, such as the C / X / Ku three-frequency band, the X / Ku / Ka three-frequency band, etc. Therefore, the present invention can not only be used as a broadband self-tracking feed, but also as a multi-frequency band self-tracking feed. The present invention is applicable to multiple application fields such as broadband feeds, multi-frequency band feeds, broadband self-tracking feeds, and multi-frequency band self-tracking feeds.

[0023] 5. The structure of the present invention is compact and convenient for realizing miniaturized design. The present invention realizes the monopulse self-tracking function through the multi-mode sharing technology, in which both the sum mode and the difference mode are radiated through the coaxial four-ridge horn aperture plane, and the horn feed maintains a small size both axially and radially.

[0024] 6. The sum-difference beam synthesis network of the present invention has a simple structure and is easy to realize. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a three-dimensional structural schematic diagram of an ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed.

[0026] Figure 2 is a front structural schematic diagram of an ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed.

[0027] Figure 3 is a cross-sectional structural schematic diagram of an ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed.

[0028] Figure 4 is a schematic diagram of a sum-difference beam synthesis network.

[0029] Figure 5 is a data graph of the reflection coefficients of the sum mode and the difference mode of the feed. In the figure, the horizontal axis is the frequency and the vertical axis is the reflection coefficient.

[0030] Figure 6 is the sum mode and difference mode radiation patterns of the feed irradiating a 5-meter standard front-feed reflector antenna at 3 GHz.

[0031] Figure 7 It is the sum-mode and difference-mode radiation patterns of a 5-meter standard front-feed reflector antenna irradiated by a feed at 6 GHz.

[0032] Figure 8 It is the sum-mode and difference-mode radiation patterns of a 5-meter standard front-feed reflector antenna irradiated by a feed at 9 GHz.

[0033] Figure 9 It is the sum-mode and difference-mode radiation patterns of a 5-meter standard front-feed reflector antenna irradiated by a feed at 12 GHz.

[0034] Figure 10 It is the sum-mode and difference-mode radiation patterns of a 5-meter standard front-feed reflector antenna irradiated by a feed at 15 GHz.

[0035] Figures 6 to 10 In the figures, the horizontal axis is the angle and the vertical axis is the amplitude.

[0036] Explanation of reference numerals: Outer conductor of coaxial horn—1, Ridge piece—2, Inner conductor of coaxial horn—3, Choke groove—4, Probe—5, Reflection cavity—6, Bottom plate—7. Detailed implementation mode

[0037] The present invention will be further described in detail below with reference to the accompanying drawings.

[0038] An ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed includes a coaxial horn, which consists of an outer conductor of the coaxial horn and an inner conductor of the coaxial horn nested together. The inner wall curve of the outer conductor of the coaxial horn is divided into two sections from back to front. The first section is a straight section with a constant radial height, and the second section is a spline function curve section. The contour curve of the inner conductor of the coaxial horn is divided into two sections from back to front. The first section is a straight section with a constant radial height, and the second section is a spline function curve section. Among them, the radius of the inner conductor of the coaxial horn in the spline function curve section gradually decreases to form a conical structure. On the inner wall of the outer conductor of the coaxial horn, identical ridge pieces are provided at 0°, 90°, 180°, and 270° along the circumferential direction. The two ridge pieces at 0° and 180° form a pair of horizontal ridges, which are responsible for horizontal polarization signals. The two ridge pieces at 90° and 270° form a pair of vertical ridges, which are responsible for vertical polarization signals. The two pairs of ridge pieces are perpendicular to each other. The ridge curve of each ridge piece is divided into three sections from back to front. The first section is a straight section with a constant radial height, the second section is a linearly expanding section with a gradually increasing radial height, and the third section is a spline function curve section. A probe perpendicular to the axis direction of the coaxial horn is provided at the tail of each ridge piece. The probe passes through the outer conductor of the coaxial horn and the ridge piece in an insulating manner and then inserts into the inner conductor of the coaxial horn. The front end of the inner conductor of the coaxial horn extends out of the mouth surface of the coaxial horn.

[0039] In addition, the present invention also provides an ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed system, which includes the ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed as described above, and also includes a sum-difference beam synthesis network. Four probes of the ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed are all connected to the sum-difference beam synthesis network through SMA sockets. The sum-difference beam synthesis network includes two 180° bridges, a 3dB power divider and a 90° bridge. The sum beam signal is synthesized through two 180° bridges and a 90° bridge, and the difference beam signal is synthesized through two 180° bridges and a 3dB power divider.

[0040] Figure 1 The figure shows a three-dimensional structural schematic diagram of the ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed established in the commercial software CST. Figure 2 The figure shows a front structural schematic diagram of the ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed established in the commercial software CST. Figure 3 The figure shows a cross-sectional structural schematic diagram of the ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed established in the commercial software CST. The ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed includes a coaxial horn outer conductor 1, ridge pieces 2, a coaxial horn inner conductor 3, choke grooves 4, probes 5, a reflection cavity 6 and a bottom plate 7.

[0041] The ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed is a pure metal structure without dielectric materials, which is easy to process and implement.

[0042] The coaxial horn outer conductor 1 is a circular-aperture horn, and its inner wall curve is divided into two sections. The first section is a straight section with a constant radial height, which is used to ensure the stable transmission of the energy fed into the horn by the probe 5. The second section is a spline function curve section, and its contour shape is interpolated and fitted by 10 discrete points distributed along the axial direction, which is used to achieve good transmission characteristics and radiation characteristics within the broadband frequency range.

[0043] The ridge pieces 2 are connected to the inner wall of the coaxial horn outer conductor 1. The root curve of the ridge pieces 2 is consistent with the inner wall curve of the coaxial horn outer conductor 1. The ridge curve of the ridge pieces 2 is divided into three sections. The first section is a straight section with a constant radial height, which is used to ensure the stable transmission of the energy fed by the probe 5. The second section is a linearly expanding section with a gradually increasing radial height, which is used to guide the energy to transition from the feeding part to the horn entrance. The third section is a spline function curve section, and its contour shape is interpolated and fitted by 10 discrete points distributed along the axial direction, which is used to achieve good transmission characteristics and radiation characteristics within the broadband frequency range.

[0044] The coaxial horn inner conductor 3 is nested in the coaxial horn outer conductor 1, and the coaxial horn inner conductor 3 is consistent with the central axis of the coaxial horn outer conductor 1. In order to ensure that the feed and beam achieve a high aperture efficiency within the broadband frequency range, the radius of the coaxial horn inner conductor 3 cannot exceed 0.1 , where is the wavelength corresponding to the lowest frequency.

[0045] The inner conductor 3 of the coaxial horn extends out of the aperture of the outer conductor 1 of the coaxial horn, and the extension length is 0.05 -0.1 , which is used to improve the transmission characteristics of the feed difference beam and enhance the aperture efficiency of the feed and the beam. Among them, is the wavelength corresponding to the lowest frequency.

[0046] The contour curve of the inner conductor 3 of the coaxial horn is divided into two sections. The first section is a straight line segment with a constant radial height, which is used to ensure that the energy fed by the probe 5 is transmitted smoothly between the ridge piece 2 and the inner conductor 3 of the coaxial horn. The second section is a spline function curve segment. The overall shape of the inner conductor 3 of the spline function curve segment is a conical structure with a gradually decreasing radius, which is used to achieve good transmission characteristics of the feed differential mode.

[0047] In order to ensure the processing accuracy, the vertex radius of the head of the inner conductor 3 of the coaxial horn is set to 0.5 mm.

[0048] The choke groove 4 is located at the head of the outer conductor 1 of the coaxial horn. The number of choke grooves 4 is 2, which is used to improve the rotational symmetry of the radiation pattern of the feed sum and differential modes and improve the antenna aperture efficiency.

[0049] The probe 5 is located at the tail of the ridge piece 2. The probes 5 correspond to the ridge pieces 2 one by one, and the number is 4. The probes 5 pass through the outer conductor 1 of the coaxial horn and the ridge piece 2 and then are inserted into the inner conductor 3 of the coaxial horn.

[0050] A ultra-wideband multi-mode self-tracking coaxial four-ridge horn feed system. Based on the above coaxial four-ridge horn feed, this feed system is externally connected to a sum-difference beam synthesis network through the probe 5, which is used to excite the TE 11 mode and TEM mode of the coaxial waveguide.

[0051] Among them, by simultaneously exciting a pair of horizontally placed probes 5 with equal amplitude at the initial phases of 0° and 180°, a horizontally polarized TE 11 mode can be obtained. By simultaneously exciting a pair of vertically placed probes 5 with equal amplitude at the initial phases of 0° and 180°, a vertically polarized TE 11 mode can be obtained. By simultaneously exciting the four probes 5 with equal amplitude at the initial phases of 0°, 0°, 0°, and 0°, a TEM mode can be obtained.

[0052] The reflection cavity 6 is located between the probe 5 and the bottom plate 7 at the tail of the outer conductor 1 of the coaxial horn, and is a circular cylindrical structure. The axial length of the reflection cavity 6 is 0.25 , which is used to achieve good excitation of the sum-difference mode signals from the coaxial probe to the coaxial ridge waveguide. Among them, is the wavelength corresponding to the lowest frequency.

[0053] As Figure 4 shown, the sum-difference beam synthesis network consists of two 180° bridges, a 3dB power divider and a 90° bridge.

[0054] Among them, the sum beam signal is synthesized through two 180° bridges and a 90° bridge. A pair of horizontally placed probes 5 form a horizontally polarized coaxial TE 11 mode through the 180° channel of the 180° bridge, and a pair of vertically placed probes 5 form a vertically polarized coaxial TE 11 mode through the 180° channel of the 180° bridge. The horizontally polarized TE 11 mode and the vertically polarized TE 11 mode are then synthesized into a circularly polarized TE 11 mode through the 90° bridge. The two ports of the 90° bridge respectively output a left-handed circularly polarized (LHCP) TE 11 mode signal and a right-handed circularly polarized (RHCP) TE 11 mode signal; the difference beam signal is synthesized through two 180° bridges and a 3dB power divider. Two sets of horizontally and vertically placed probes 5 respectively form two sets of synthesized signals through the 0° channel of the 180° bridge, and the two sets of synthesized signals are finally synthesized into a coaxial TEM mode signal through the 3dB power divider.

[0055] Taking a multimode self-tracking coaxial four-ridge horn feed operating at 3 - 15GHz as an example, its transmission and radiation performance is verified. The half illumination angle of the feed is 50°. The reflection coefficients and far-field radiation patterns of the sum and difference modes of the feed are calculated using the commercial software CST, and the antenna radiation pattern of the feed illuminating the reflector antenna is calculated using the commercial software Grasp.

[0056] Figure 5 are the reflection coefficients of the sum and difference modes of the feed. It can be seen that within the operating frequency band of 3 - 15GHz, the reflection coefficient of the sum mode (linear polarization) of the feed is lower than -13.78dB, and the reflection coefficient of the difference mode is lower than -7.93dB. Both the sum and difference modes have good transmission characteristics.

[0057] The 5-meter standard front-feed reflector antenna with a focal ratio of 0.535 is illuminated by the feed. Figures 6 to 10 are the sum and difference mode antenna patterns at typical frequency points under different frequencies. It can be seen that both the sum and difference beams of the antenna have relatively high gains, the sum-difference contradiction is small, the null depth of the difference beam is obvious, and the difference slope is large. After calculation, within the frequency band of 3 - 15GHz, the aperture efficiency of the antenna is higher than 62.3%, and the normalized difference gain (the difference between the peak of the difference gain and the peak of the sum gain) is higher than -10dB. The overall electrical performance of the antenna is excellent.

[0058] In summary, the present invention adopts TE in the coaxial waveguide. 11The dual-mode sharing technology of the mode / TEM mode can simultaneously achieve communication functions and self-tracking functions within a five-fold frequency bandwidth. The sum and difference channels of the present invention have excellent performance, are structurally compact, and have a wide range of application scenarios, and it is a novel and easy-to-implement ultra-wideband monopulse self-tracking feed system.

Claims

1. An ultra-wideband multi-mode self-tracking coaxial four-ridged horn feed, comprising a coaxial horn, wherein the coaxial horn comprises a coaxial horn outer conductor and a coaxial horn inner conductor nested together; characterized in that: The inner wall curve of the outer conductor of the coaxial horn is divided into two sections from back to front, the first section is a straight line section with a constant radial height, and the second section is a spline function curve section; the contour curve of the inner conductor of the coaxial horn is divided into two sections from back to front, the first section is a straight line section with a constant radial height, and the second section is a spline function curve section, wherein the radius of the inner conductor of the coaxial horn in the spline function curve section gradually decreases to form a conical structure; the inner wall of the outer conductor of the coaxial horn is provided with the same ridge pieces at 0°, 90°, 180°, and 270° along the circumferential direction, and the ridge curve of the ridge piece is divided into three sections from back to front, the first section is a straight line section with a constant radial height, the second section is a linear open section with a gradually increasing radial height, and the third section is a spline function curve section; a probe perpendicular to the axis direction of the coaxial horn is provided at the tail of each ridge piece, and the probe is inserted into the inner conductor of the coaxial horn after passing through the outer conductor and the ridge piece of the coaxial horn in an insulated manner; the front end of the inner conductor of the coaxial horn extends out of the mouth surface of the coaxial horn.

2. The ultra-wideband multi-mode self-tracking coaxial four-ridged horn feed according to claim 1, characterized in that: The length of the inner conductor of the coaxial horn extending outside the coaxial horn mouth is 0.05 -0.1 ,in, is the wavelength corresponding to the lowest frequency.

3. The ultra-wideband multi-mode self-tracking coaxial four-ridged horn feed according to claim 1, characterized in that: The maximum radius of the conductor inside the coaxial speaker does not exceed 0.1 ,in, is the wavelength corresponding to the lowest frequency.

4. The ultra-wideband multi-mode self-tracking coaxial four-ridged horn feed according to claim 1, characterized in that: The radius of the top point of the conductor head in the coaxial speaker is 0.3-0.7 mm.

5. The ultra-wideband multi-mode self-tracking coaxial quad-ridged horn feed according to claim 1, characterized in that: A bottom plate is arranged at the tail of the coaxial horn, and a reflection cavity is arranged between the probe and the bottom plate, wherein the reflection cavity is a circular cylindrical structure.

6. The ultra-wideband multi-mode self-tracking coaxial quad-ridged horn feed according to claim 1, characterized in that: The head of the outer conductor of the coaxial horn is also provided with a choke slot.

7. The ultra-wideband multi-mode self-tracking coaxial four-ridged horn feed according to claim 6, characterized in that: The number of the choke slots is 2.

8. An ultra-wideband multi-mode self-tracking coaxial four-ridged horn feed system, characterized in that: The invention comprises an ultra-wideband multi-mode self-tracking coaxial four-ridged horn feed as claimed in any one of claims 1 to 7, and also comprises a sum-difference beam synthesis network; four probes of the ultra-wideband multi-mode self-tracking coaxial four-ridged horn feed are connected to the sum-difference beam synthesis network through SMA sockets; The sum and difference beam synthesis network includes two 180° bridges, a power divider and a 90° bridge, the sum beam signal is synthesized via the two 180° bridges and the 90° bridge, and the difference beam signal is synthesized via the two 180° bridges and the power divider; When synthesizing and beaming signals, a pair of horizontally placed probes pass through the 180° channel of the 180° bridge to form a horizontally polarized coaxial TE 11 A pair of probes placed vertically pass through the 180° channel of the 180° bridge to form a vertically polarized coaxial TE 11 Mode, horizontal polarization TE 11 mode and vertically polarized TE 11 The mode is then synthesized into circularly polarized TE by a 90° bridge. 11 The two ports of the 90° bridge output left-hand circularly polarized TE 11 Mode signal and right-hand circular polarization TE 11 analog signal; When synthesizing the difference beam signal, the two groups of probes placed horizontally and vertically are respectively passed through the 0° channels of the two 180° bridges to form two groups of synthetic signals, which are then synthesized into coaxial TEM mode signals through a power divider.

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