Ka-band circular polarizer device

Abstract

The utility model discloses a Ka frequency band circular polarizer device, which relates to the technical field of satellite communication, and comprises an upper circular waveguide, a square waveguide and a lower circular waveguide, the square waveguide is connected between the upper circular waveguide and the lower circular waveguide, the left side and the right side of the square waveguide are respectively inserted with a group of metal diaphragms, the upper circular waveguide is in non-directional connection with the square waveguide, and the lower circular waveguide is in non-directional connection with the square waveguide. And the lower circular waveguide is in non-directional connection with the square waveguide. According to the Ka-band circular polarizer device, the metal diaphragms realize the broadband characteristic of the circular polarizer through a plurality of pairs of discontinuous diaphragms, and the number of pairs of the metal diaphragms is reduced by adjusting the depths of the diaphragms, so that the length of the circular polarizer is reduced, the bandwidth work of the circular polarizer device in the Ka band is realized, and the Ka-band circular polarizer device is simple in structure and more practical.

Description

Technical Field

[0001] The utility model relates to the technical field of satellite communications, in particular to a Ka-band circular polarizer device. Background Art

[0002] Satellite communication systems operating in the Ka band have the advantages of improving the system's anti-interference, confidentiality, anti-destruction, and flexibility, so they have been developed and widely used. The uplink frequency of the Ka band satellite communication system is 27.5 to 31 GHz, and the downlink frequency is 17.7 to 21.2 GHz.

[0003] In the field of satellite communications, circularly polarized reflector antennas, mainly in the form of parabolic antennas, are widely used. As an important component of the antenna feed system, the circular polarizer converts linear polarization signals into circular polarization signals, or converts received circular polarization signals into linear polarization signals. Therefore, a circular polarizer with excellent performance is crucial to improving the circular polarization performance of the antenna system.

[0004] A circular waveguide circular polarizer is generally realized by screw phase shifting or diaphragm phase shifting. Since the inductive susceptance of the screws in the circular waveguide is very small and the frequency band is narrow, more screws than diaphragms are required to realize circular polarization, which increases the longitudinal length and makes the structure more complicated. Therefore, this application proposes a Ka-band circular polarizer device to solve the above problem. Utility Model Content

[0005] 1. Technical issues to be resolved

[0006] In view of the deficiencies in the prior art, the utility model provides a Ka-band circular polarizer device, which solves the technical problems raised in the above background.

[0007] (II) Technical solution

[0008] To achieve the above purpose, the technical solution adopted by the utility model is: a Ka-band circular polarizer device, including an upper circular waveguide, a square waveguide, and a lower circular waveguide, and the square waveguide is connected between the upper circular waveguide and the lower circular waveguide, a group of metal diaphragms are inserted on the left and right sides of the square waveguide, the upper circular waveguide is non-directionally connected to the square waveguide, and the lower circular waveguide is non-directionally connected to the square waveguide.

[0009] Preferably, the upper circular waveguide is connected to the front-end device of the antenna, and the lower circular waveguide is connected to the rear-end device of the antenna.

[0010] Preferably, the two groups of metal diaphragms are symmetrically arranged based on a square waveguide.

[0011] Preferably, the upper circular waveguide inputs a Ka frequency signal.

[0012] Preferably, the metal diaphragms on the left and right sides of the square waveguide are used to change the propagation constants of the two polarization orthogonal modes in the square waveguide, so that the two modes at the output end have equal amplitude and a phase difference of 90° to form a circularly polarized wave, and the lower circular waveguide is connected to the rear end device of the antenna.

[0013] (III) Beneficial effects

[0014] The beneficial effects of the utility model are:

[0015] In the Ka-band circular polarizer device, the metal diaphragm realizes the broadband characteristics of the circular polarizer through multiple pairs of discontinuous diaphragms. The number of metal diaphragm pairs is reduced by adjusting the diaphragm depth. The effective working bandwidth in the Ka-band is set to 27.5-31 GHz for uplink and 17.7-21.2 GHz for downlink, with a bandwidth of 3.5 GHz, thereby reducing the length of the circular polarizer and realizing the broadband operation of the circular polarizer device in the Ka-band. The structure is simple and more practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the three-dimensional structure of the utility model;

[0017] Figure 2 This is a schematic diagram of the planar structure of the utility model;

[0018] Figure 3 The data diagram of transmission characteristic parameters (voltage standing wave ratio) of the upper circular waveguide and the lower circular waveguide outlet in the ka-band;

[0019] Figure 4 The transmission characteristic parameter (transmission coefficient) data diagram of the upper circular waveguide and the lower circular waveguide outlet in the ka-band;

[0020] Figure 5 This is the phase difference data of the two orthogonal polarization modes at the outlet of the upper circular waveguide and the lower circular waveguide in the Ka-band.

[0021] In the figure: 1 upper circular waveguide, 2 square waveguide, 3 lower circular waveguide, 4 metal diaphragm. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] Example

[0024] like Figure 1 , Figure 2As shown, a Ka-band circular polarizer device comprises an upper circular waveguide 1, a square waveguide 2, and a lower circular waveguide 3, wherein the square waveguide 2 is connected between the upper circular waveguide 1 and the lower circular waveguide 3, a group of metal diaphragms 4 are inserted into the left and right sides of the square waveguide 2, the upper circular waveguide 1 is non-directionally connected to the square waveguide 2, the lower circular waveguide 3 is non-directionally connected to the square waveguide 2, the upper circular waveguide 1 is connected to the antenna front-end device, the two groups of metal diaphragms 4 are symmetrically arranged based on the square waveguide 2, and the metal diaphragms 4 on the left and right sides of the square waveguide 2 are respectively inserted into the right and left sides of the square waveguide 2. The metal diaphragm 4 is used to change the propagation constant of the two polarization orthogonal modes in the square waveguide, so that the two modes at the output end have equal amplitude and a phase difference of 90°, forming a circularly polarized wave. The lower circular waveguide 3 is connected to the rear-end device of the antenna. The metal diaphragm 4 realizes the broadband characteristics of the circular polarizer through multiple pairs of discontinuous diaphragms. The number of pairs of metal diaphragms 4 is reduced by adjusting the depth of the diaphragm, thereby reducing the length of the circular polarizer, realizing the broadband operation of the circular polarizer device in the Ka band, and the structure is simple and more practical.

[0025] In actual use, the effective working bandwidth of the Ka-band circular polarizer device in the Ka-band is 27.5-31 GHz for uplink and 17.7-21.2 GHz for downlink, with a bandwidth of 3.5 GHz. A Ka-frequency signal is input at the upper circular waveguide 1, and the square waveguide 2 changes the propagation constants of the two polarization orthogonal modes in the square waveguide through the metal diaphragms 4 on the left and right sides, so that the lower circular waveguide 3 outputs a Ka-frequency signal with equal amplitude and a phase difference of 90° with the two modes input by the upper circular waveguide 1, forming a circularly polarized wave;

[0026] After testing the output ports, the results are as follows Figure 3-Figure 5 As shown,

[0027] in Figure 3 It is the transmission characteristic parameter (voltage standing wave ratio) data of the outlets of the upper circular waveguide 1 and the lower circular waveguide 3 in the ka-band;

[0028] Figure 4 It is the transmission characteristic parameter (transmission coefficient) data of the outlets of the upper circular waveguide 1 and the lower circular waveguide 3 in the ka-band;

[0029] Figure 5 It is the phase difference data of two polarization orthogonal modes at the exits of upper circular waveguide 1 and lower circular waveguide 3 in the ka-band.

[0030] From the above data, it can be seen that the Ka frequency signal has good transmission performance at the exits of the upper and lower circular waveguides 3. The signal output at the exit of the lower circular waveguide 3 is basically equal to the signal input at the upper circular waveguide 1 in amplitude, the phase difference is within the range of 90°±12°, and the equivalent axial ratio is less than 1.83dB.

[0031] In the description of the present invention, it is necessary to understand that the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0032] In the present invention, unless otherwise clearly stipulated and limited, for example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, for ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0033] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A Ka-band circular polarizer device, characterized in that: The invention comprises an upper circular waveguide (1), a square waveguide (2) and a lower circular waveguide (3), wherein the square waveguide (2) is connected between the upper circular waveguide (1) and the lower circular waveguide (3), a group of metal diaphragms (4) are inserted into the left and right sides of the square waveguide (2), the upper circular waveguide (1) is non-directionally connected to the square waveguide (2), and the lower circular waveguide (3) is non-directionally connected to the square waveguide (2).

2. A Ka-band circular polarizer device according to claim 1, characterized in that: The upper circular waveguide (1) is connected to the front-end device of the antenna, and the lower circular waveguide (3) is connected to the rear-end device of the antenna.

3. A Ka-band circular polarizer device according to claim 2, characterized in that: The two groups of metal diaphragms (4) are symmetrically arranged based on the square waveguide (2).

4. A Ka-band circular polarizer device according to claim 3, characterized in that: The upper circular waveguide (1) inputs a Ka frequency signal.

5. A Ka-band circular polarizer device according to claim 4, characterized in that: The metal diaphragms (4) on the left and right sides of the square waveguide (2) are used to change the propagation constants of two polarization orthogonal modes in the square waveguide.

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