Multi-band ring-focus antenna with biased sub-patches and its method of biased sub-patch secondary shaping
Patent Information
- Application Number
- CN202310261351.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-03-17
- Publication Date
- 2026-10-23
- Estimated Expiration
- 2043-03-17
AI Technical Summary
但是，由于非工作馈源可能对天线造成遮挡，所以天线电气性能明显下降，且换馈机构复杂，当馈源网络移动或转动过程中，其馈线和后端设备也必须作相应的移动或转动，稳定性差
[0025]1、本发明提出的环焦天线具有偏置的副面，该副面分别对应多个不同频段的馈源，即可实现天线系统的多频段工作。
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Figure CN116259976B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of communication technology, and in particular to a multi-band loop-focus antenna with a bias sub-plane and a secondary shaping method for the bias sub-plane. Background Technology
[0002] In the field of microwave communication, there are several types of reflector antennas that can operate at multiple frequencies. Although each has its own characteristics in terms of performance, they all have some shortcomings.
[0003] 1. A conventional reflector antenna with a multi-band feed network can achieve multi-band operation. However, the frequency range that a multi-band feed network can cover is limited, making it difficult to achieve multi-band operation of more than three bands. In addition, the electrical performance of multi-band antennas is relatively lower than that of single-band antennas.
[0004] 2. Conventional reflector antennas with multiple feed networks can achieve multi-band operation through translational or rotational feed switching. However, since non-operating feeds may obstruct the antenna, the antenna's electrical performance is significantly degraded. Furthermore, the feed switching mechanism is complex, and when the feed network moves or rotates, its feed lines and back-end equipment must also move or rotate accordingly, resulting in poor stability.
[0005] 3. Standard Cassegrain antennas use a front-feed and back-feed configuration to achieve multi-band operation, but only two feeds can be placed at the main focal point and the secondary focal point. This makes them unsuitable for feed networks with more than three feeds. Furthermore, because the antenna cannot be shaped, its efficiency is low. In addition, the installation, maintenance, and repair of front-feed feed networks are not convenient. Summary of the Invention
[0006] The purpose of this invention is to overcome the shortcomings of the above-mentioned background technology and provide a multi-band loop-focus antenna with a bias sub-surface. This antenna does not require a complex feed switching mechanism or complex feed lines. It can realize the multi-band operation of the loop-focus antenna system simply by having the bias sub-surface correspond to multiple feed sources of different frequency bands. It has the characteristics of simple structure and stable performance and is suitable for use as an antenna system with multi-band operation.
[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0008] A multi-band ring-focus antenna with a bias sub-face includes a main face, a sub-face, and a feed group consisting of multiple feeds of different frequency bands; each feed of the feed group is fixed, the sub-face is located in the illumination direction of the feed, and the axis of the sub-face has an angle greater than zero with the axis of the main face; when the sub-face rotates around the axis of the main face, the focal trajectory of the sub-face is a ring.
[0009] Furthermore, the phase center of the feed source is placed at the corresponding position of the sub-plane focal trajectory ring, and the beam center of the feed source points to the sub-plane center.
[0010] Furthermore, the secondary surface is formed by a secondary shaping method.
[0011] Furthermore, the specific process for designing the sub-surface in a multi-band loop-focus antenna with a bias sub-surface as described in any of the above is as follows:
[0012] In the initial design, the antenna's principal surface is parabolic, and its secondary surface is elliptical. Points F1 and F2 are the two foci of the secondary surface, and point F2 is the focus of the parabolic principal surface. Point F2 forms a focal ring around the antenna axis. When the antenna is operating, the phase center of the feed is located at the focus F1 of the secondary surface. The parameters of the loop-focal antenna are: principal surface diameter D... m Secondary diameter D s , feed angle θm and principal face angle ψ;
[0013] The focal point F1 of the secondary surface is offset from the antenna's axis of symmetry to point F1'. The secondary surface of the ring-focal antenna is then reshaped so that any ray emitted from the focal point F1' is reflected by the secondary surface to the primary surface, and then reflected by the primary surface to exit along a direction parallel to the antenna axis. The optical path traversed to reach the reference plane perpendicular to the antenna axis is equal.
[0014] Point S is any point on the secondary surface, and point M is the point on the primary surface corresponding to point S. When a microwave ray is emitted from point F1' to point S on the secondary surface, it is reflected by the secondary surface and propagates towards point M on the primary surface. After being reflected by point M, it propagates in a direction parallel to the rotation axis of the primary surface. On any given plane perpendicular to the rotation axis of the primary surface, all optical path lengths are equal regardless of the changes in points S and M. The coordinates of the secondary surface point S(X) are given by the secondary surface point. S ,Y S Z S This can be represented as:
[0015]
[0016] (X m Y m Z m Let M be the coordinates of point M; where M is the coordinates of point M. It is the spatial vector pointing from point S to point M. It is the length of the vector. It is the unit vector of this vector, L x It is a unit vector The component on the X-axis, L y It is a unit vector The component on the y-axis, L z It is a unit vector The component on the z-axis; since the vector direction from any point on the secondary face to the corresponding point on the primary face remains unchanged before and after the secondary shaping, i.e. It is known;
[0017] Setting the equiphase reference plane in the xoy plane, we know from the equal optical path condition that...
[0018]
[0019] Among them, (X) F’1 ,Y F’1 Z F’1 ) represents the coordinates of F1', m x m y m z Let be the projections of the unit vectors from point S on the secondary surface to point M on the principal surface onto the x, y, and z coordinate axes; if the equal optical path C is obtained... k Then it is possible to solve for all points corresponding to points on the bias secondary face and the principal face;
[0020] Points P and Q are the left and right edges of the subsurface on the xoz plane after the first shaping, respectively; points P' and Q' are the left and right edges of the subsurface on the xoz plane after the second shaping, respectively; based on the equal optical path condition, the microwave rays emitted from point F1' are reflected by points P' and Q' and then propagate to points U and V corresponding to the principal face. After further reflection by points U and V, the rays are parallel to the rotation axis of the principal face, and the sum of all the paths traversed before reaching the plane orthogonal to the rotation axis of the principal face is equal; thus, we can obtain...
[0021]
[0022] Where, the coordinates of P' are (X' P ,Y' P ,Z' P The coordinates of Q' are (X') Q ,Y' Q ,Z' Q );Z U and Z VF Let U and V be the Z-axis coordinates of points U and V, respectively; the optical path C can be obtained by solving the above system of equations. k ;
[0023] Through the above calculations, the coordinate value of any point S on the secondary shaping surface can be obtained, thus obtaining a ring-focus antenna with an offset secondary surface. In this new antenna system, the new focal point F1' rotates around the main surface symmetry axis OF1 to form a circle. Multiple feed sources can be arranged on this circle, and the offset secondary surface can correspond to each feed source.
[0024] Compared with the prior art, the present invention has the following advantages:
[0025] 1. The ring-focal antenna proposed in this invention has a biased sub-plane, which corresponds to multiple feed sources of different frequency bands, thereby realizing the multi-frequency operation of the antenna system.
[0026] 2. In the antenna system of the present invention, the feed group is fixed and the downstream accompanying equipment connected to each feed is also fixed, eliminating the need for complex feed switching mechanisms such as translation and rotation, thus greatly simplifying the structure.
[0027] 3. The antenna of the present invention does not need to use a complex multi-band feed network. It can span a wider range of operating frequency bands with just a single-frequency feed, and its performance is greatly improved. Attached Figure Description
[0028] Figure 1 This is a schematic diagram of the ring focal antenna of the present invention.
[0029] In the diagram: 1. Main face; 2. Offset secondary face; 3. Feed group.
[0030] Figure 2 This is a schematic diagram of the ring-focal antenna of the initial design of this invention.
[0031] Figure 3 This is a schematic diagram of the ring-focal antenna with secondary shaping according to the present invention. Detailed Implementation
[0032] The present invention will now be further described with reference to the accompanying drawings.
[0033] Reference Figure 1 This invention proposes a special ring-focus antenna system, comprising a main surface 1, an offset sub-surface 2, and a feed group 3 composed of multiple horns operating at different frequency bands. In this antenna system, the main surface 1 remains unchanged compared to a conventional ring-focus antenna. The sub-surface 2 is offset after secondary shaping. The multiple feeds of the feed group 3 are arranged on a circle formed with the axis of symmetry of the main surface as the axis. The feed group 3 remains fixed. When the offset sub-surface 2 corresponds to a certain feed, that feed is operational. By changing the position of the offset sub-surface, the ring-focus antenna can operate in multiple frequency bands.
[0034] The specific design method of the present invention will be further described below with reference to the accompanying drawings.
[0035] Reference Figure 2 In the initial design of the ring-focal antenna, the principal surface is parabolic, and the secondary surface is elliptical. Points F1 and F2 are the two foci of the secondary surface, and point F2 is the focus of the parabolic principal surface. This point forms a focal ring around the antenna axis. When the antenna is operating, the phase center of the feed is located at the focus F1 of the secondary surface. The parameters of the ring-focal antenna are: principal surface diameter D... m Secondary diameter D s The feed angle θm and principal plane angle ψ are determined by the law of conservation of energy and the law of reflection. Initial shaping of the ring-focal antenna can improve its gain and reduce sidelobes. At this point, the principal plane focus forms a focal ring region near the original focal ring.
[0036] Furthermore, refer to Figure 3 The focal point F1 of the secondary surface is offset from the antenna's axis of symmetry to point F1'. The secondary surface of the ring-focal antenna is then reshaped twice, so that any ray emitted from the focal point F1' is reflected by the secondary surface to the primary surface, then reflected again by the primary surface, and emitted along a direction parallel to the antenna axis, reaching a reference plane perpendicular to the antenna axis with equal optical path length. It is important to note that, to improve the versatility of the primary surface mold, the curve of the primary surface remains unchanged; only the secondary surface is reshaped twice. Therefore, the rays on the primary surface are invariant; that is, the incident and reflection directions at any point on the primary surface are fixed. The rays from the secondary-shaped secondary surface onto points on the primary surface must conform to the ray trace of that point.
[0037] Furthermore, point S is any point on the secondary surface, and point M is the point on the primary surface corresponding to point S. When a microwave ray is emitted from point F1' to point S on the secondary surface, it is reflected by the secondary surface and propagates towards point M on the primary surface. After being reflected by point M, it propagates in a direction parallel to the rotation axis of the primary surface. On any given plane perpendicular to the rotation axis of the primary surface, all optical path lengths remain equal regardless of the changes in points S and M. The coordinates of the secondary surface point S(X) are given by... S ,Y S Z S This can be represented as:
[0038]
[0039] in It is the spatial vector pointing from point S to point M. It is the length of the vector. It is the unit vector of this vector, L x It is a unit vector The component on the X-axis, L y It is a unit vector The component on the y-axis, L z It is a unit vector The component on the z-axis. Since the direction of the vector from any point on the secondary face to the corresponding point on the primary face remains unchanged before and after the secondary shaping, i.e. It is known.
[0040] Setting the equiphase reference plane in the xoy plane, we know from the equal optical path condition that...
[0041]
[0042] Among them, (X) F’1 ,Y F’1 Z F’1 ) represents the coordinates of F1', m x m y m zLet be the projections of the unit vectors from point S on the secondary surface to point M on the principal surface onto the x, y, and z coordinate axes; if the equal optical path C is obtained... k Then it is possible to solve for all points corresponding to points on the bias secondary face and the principal face;
[0043] Points P and Q are the left and right edges of the subsurface on the xoz plane after the first shaping, respectively; points P' and Q' are the left and right edges of the subsurface on the xoz plane after the second shaping, respectively; based on the equal optical path condition, the microwave rays emitted from point F1' are reflected by points P' and Q' and then propagate to points U and V corresponding to the principal face. After further reflection by points U and V, the rays are parallel to the rotation axis of the principal face, and the sum of all the paths traversed before reaching the plane orthogonal to the rotation axis of the principal face is equal; thus, we can obtain...
[0044]
[0045] The optical path C can be obtained by solving the above system of equations. k .
[0046] Through the above calculations, the coordinates of any point S on the secondary shaping surface can be obtained, thus obtaining a ring-focus antenna with an offset secondary surface. In this new antenna system, the new focal point F1' rotates around the main surface symmetry axis OF1 to form a circle. Multiple feed sources can be arranged on this circle, and the offset secondary surface can correspond to each feed source.
[0047] The working principle of this invention is as follows: Through secondary shaping design of the ring-focus antenna, a ring-focus antenna system including a main surface 1, an offset sub-surface 2 and a feed group 3 is obtained. The offset sub-surface can correspond to each feed in the feed group 3, realizing the multi-band operation of the antenna system.
Claims
1. A multi-band loop-focus antenna with a bias sub-face, comprising a main face, a sub-face, and a feed group consisting of multiple feeds of different frequency bands; characterized in that, Each feed in the feed group is fixed, the sub-face is located in the illumination direction of the feed, and there is a greater than zero angle between the axis of the sub-face and the axis of the main face; when the sub-face rotates around the axis of the main face, the trajectory of the sub-face focus is a ring. The phase centers of the feed source are respectively placed at the corresponding positions of the sub-plane focal trajectory ring, and the beam center of the feed source points to the sub-plane center; The secondary surface is formed by a secondary shaping method.
2. A method for secondary shaping of the offset sub-plane of a multi-band loop-focus antenna, characterized in that, The specific process for designing the sub-surface in a multi-band loop-focus antenna with a bias sub-surface as described in claim 1 is as follows: In the initial design, the antenna's principal surface is parabolic, and its secondary surface is elliptical. Points F1 and F2 are the two foci of the secondary surface, and point F2 is the focus of the parabolic principal surface. Point F2 forms a focal ring around the antenna axis. When the antenna is operating, the phase center of the feed is located at the focus F1 of the secondary surface. The parameters of the loop-focal antenna are: principal surface diameter D... m Secondary diameter D s , feed angle θm and principal face angle ψ; The focal point F1 of the secondary surface is offset from the antenna's axis of symmetry to point F1'. The secondary surface of the ring-focal antenna is then reshaped so that any ray emitted from the focal point F1' is reflected by the secondary surface to the primary surface, and then reflected by the primary surface to exit along a direction parallel to the antenna axis. The optical path traversed to reach the reference plane perpendicular to the antenna axis is equal. Point S is any point on the secondary surface, and point M is the point on the primary surface corresponding to point S. When a microwave ray is emitted from point F1' to point S on the secondary surface, it is reflected by the secondary surface and propagates towards point M on the primary surface. After being reflected by point M, it propagates in a direction parallel to the rotation axis of the primary surface. On any given plane perpendicular to the rotation axis of the primary surface, all optical path lengths are equal regardless of the changes in points S and M. The coordinates of the secondary surface point S(X) are given. S ,Y S Z S This can be represented as: (X) m Y m Z m Let M be the coordinates of point M; where M is the coordinates of point M. It is the spatial vector pointing from point S to point M. It is the length of the vector. It is the unit vector of this vector. It is a unit vector Components on the X-axis It is a unit vector Components on the y-axis It is a unit vector The component on the z-axis; since the vector direction from any point on the secondary face to the corresponding point on the primary face remains unchanged before and after the secondary shaping, i.e. It is known; Setting the equiphase reference plane in the xoy plane, we know from the equal optical path condition that... Among them, (X) F’1 ,Y F’1 Z F’1 ) represents the coordinates of F1', m x m y m z Let be the projections of the unit vectors from point S on the secondary surface to point M on the principal surface onto the x, y, and z coordinate axes; if the equal optical path C is obtained... k Then it is possible to solve for all points corresponding to points on the bias secondary face and the principal face; Points P and Q are the left and right edges of the subsurface on the xoz plane after the first shaping, respectively; points P' and Q' are the left and right edges of the subsurface on the xoz plane after the second shaping, respectively; based on the equal optical path condition, the microwave rays emitted from point F1' are reflected by points P' and Q' and then propagate to points U and V corresponding to the principal face. After further reflection by points U and V, the rays are parallel to the rotation axis of the principal face, and the sum of all the paths traversed before reaching the plane orthogonal to the rotation axis of the principal face is equal; thus, we can obtain... Where, the coordinates of P' are (X' P ,Y' P ,Z' P The coordinates of Q' are (X') Q ,Y' Q ,Z' Q );Z U and Z V Let U and V be the Z-axis coordinates of points U and V, respectively; the optical path C can be obtained by solving the above system of equations. k ; Through the above calculations, the coordinate value of any point S on the secondary shaping surface can be obtained, thus obtaining a ring-focus antenna with an offset secondary surface. In this new antenna system, the new focal point F1' rotates around the main surface symmetry axis OF1 to form a circle. Multiple feed sources can be arranged on this circle, and the offset secondary surface can correspond to each feed source.