Improved X-shaped slot circularly polarized antenna
By designing improved slots and impedance regulators in X-shaped slot circular polarized antennas, the radiation efficiency of the antenna is improved, the problem of low radiation efficiency of SIW structure is solved, and the effect of miniaturization and cost reduction is achieved.
Patent Information
- Application Number
- CN202411308156.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-19
- Publication Date
- 2024-12-10
AI Technical Summary
The radiation efficiency of X-shaped slot circular polarized antennas based on SIW structures is low, resulting in the need of a large number of radiation units in mobile satellite communications to meet the required gain, thereby increasing the antenna size and cost.
Using an improved X-shaped slot circular polarized antenna, the electric field at the junction of the slots is adjusted by designing an improved X-shaped slot and internal impedance regulator on the top waveguide wall, including an incision design of uniform slot width and a metallized through-hole structure. and adjust impedance matching by rotating and introducing metal cylinders.
The efficiency of antenna radiation units is significantly improved, the number of radiation units is reduced, the cost of antennas is reduced, and the efficient radiation performance is maintained in large-scale arrays.
Smart Images
Figure CN119108794A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of satellite communications, and more specifically, relates to an improved X-shaped slot circularly polarized antenna. Background Art
[0002] Circularly polarized antennas have significant advantages in resisting multipath interference and simplifying polarization matching, and are widely used in wireless communication systems. Especially in the field of mobile satellite communications, circularly polarized antennas do not need to accurately match the polarization direction of the signal during reception and transmission, thereby avoiding the need for polarization tracking and greatly simplifying the installation and debugging process of antenna equipment. Therefore, satellite antennas are gradually shifting from linear polarization to circular polarization, effectively reducing the design cost of mobile satellite tracking systems and contributing to the development and commercialization of higher-level technical systems.
[0003] The X-shaped slot waveguide antenna is a traditional circularly polarized antenna. By slotting the waveguide wall at a specific position away from the center of the waveguide, the electromagnetic wave can generate circularly polarized radiation here. On the basis of using the X-shaped slot to generate circularly polarized radiation here, the radiation efficiency can be further effectively improved. By adjusting the shape and size of the X-shaped slot, the bandwidth and radiation characteristics of the antenna can be controlled. The slot antenna has the characteristics of simple structure and easy implementation, and because of its small size parameters, it is easy to implement in design. With the development of technology, the slot circularly polarized antenna based on substrate integrated waveguide (SIW) has become an ideal solution for miniaturized and high-frequency satellite communication systems due to its low profile size and low transmission loss. However, the SIW transmission line structure is a reduced height waveguide structure, and the SIW slot antenna often faces the problem of low radiation efficiency. The unit maximum radiation efficiency of the X-shaped slot circularly polarized antenna based on the SIW structure is only about 25%. This results in the need to use a large number of radiating units to meet the required gain when designing mobile satellite communication antennas, which in turn leads to an increase in antenna size and cost. Summary of the invention
[0004] In view of the above defects or improvement needs of the prior art, the present invention proposes an improved X-shaped slot circularly polarized antenna, which greatly improves the efficiency of the antenna radiation unit while maintaining a simple design structure.
[0005] To achieve the above objectives, the present invention provides an improved X-shaped slot circularly polarized antenna, which is a reduced-height waveguide structure, including an improved X-shaped slot dug out from the top waveguide wall for radiating energy and an impedance adjuster inside the waveguide for adjusting impedance matching.
[0006] In some optional embodiments, the height-reduced waveguide structure is a substrate-integrated waveguide structure, including upper and lower metal copper-clad surfaces, a dielectric substrate, and two rows of metallized through holes for forming equivalent waveguide narrow walls.
[0007] In some optional embodiments, the improved X-shaped slot inscribes a similar X-shaped slot groove with uniform slot width, and gradually reduces the slot width by inscription to change the internal uniform electric field characteristics, so that the slot width at the intersection of two slots of the X slot is smaller than the width value at both ends of the slot.
[0008] In some optional embodiments, the X-shaped slit groove is formed by the intersection of two slits with the same slit width and length, and the slit intersection point is the midpoint of the two slits.
[0009] In some optional embodiments, the two slots similar to the X-shaped slot do not intersect each other vertically, and the center line direction of the X-shaped slot is not parallel or perpendicular to the waveguide transmission direction, and has a certain inclination angle.
[0010] In some optional embodiments, the intersection point of the X-shaped slot grooves is located on one side of the center line of the antenna, and the slot is truncated adjacent to the narrow wall of the equivalent metal waveguide.
[0011] In some optional embodiments, the impedance adjuster is a metal cylinder at a preset distance from the intersection of the gaps, the metal cylinder passes through the waveguide, the top surface of the cylinder contacts the top waveguide wall, and the bottom surface of the cylinder contacts the bottom waveguide wall.
[0012] In some optional embodiments, the X-shaped slot is rotated counterclockwise around the radiation direction as a whole by a preset angle.
[0013] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:
[0014] 1) The improved X-shaped slot circularly polarized antenna proposed in the present invention significantly improves the efficiency of the antenna radiation unit while maintaining a simple design structure.
[0015] 2) The improved X-shaped slot circularly polarized antenna proposed in the present invention not only improves the overall radiation efficiency of the antenna array, but also means that the number of radiation units can be reduced when constructing a large-scale antenna array, which is of great significance both for array miniaturization and reducing antenna costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 1 is a schematic structural diagram of an example of an improved X-shaped slot circularly polarized antenna provided by an embodiment of the present invention;
[0017] Figure 2 is a performance diagram of an improved X-shaped slot circularly polarized antenna provided by an embodiment of the present invention;
[0018] Figure 3 It is a schematic diagram of the structure of a 1×4 circularly polarized linear array antenna provided in an embodiment of the present invention. DETAILED DESCRIPTION
[0019] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.
[0020] The present invention provides an improved X-shaped slot circularly polarized antenna for use in the 29 GHz Ka satellite frequency band. Figure 1 As shown, the antenna is a height-reduced waveguide structure antenna, including an improved X-shaped slot 1 dug out of the top waveguide wall for radiating energy and an impedance adjuster 2 inside the waveguide for adjusting impedance matching.
[0021] The improved X-shaped slot circularly polarized antenna in the example of the present invention adopts a top slot structure based on a single-layer SIW, including two layers of upper and lower metal copper-clad surfaces, a dielectric substrate, and two rows of metalized through holes used to form equivalent waveguide narrow walls. The two rows of metalized through holes pass through the dielectric substrate, and the upper bottom surface of the cylindrical hole contacts the upper metal copper-clad surface, and the lower bottom surface contacts the lower metal copper-clad surface, forming a closed equivalent waveguide transmission line structure. A slot groove similar to an X-shape is dug on the top of the SIW structure. The X-shaped slot groove is formed by the intersection of two slots with the same slot width and length, and the intersection point of the slot is the midpoint of the two slots. And in consideration of actual processing and axial ratio optimization, the slot 12 close to the SIW metal narrow wall is truncated. Different from the traditional X-shaped slot, a slot of uniform width is used to form a uniform electric field distribution inside the slot. As Figure 2As shown, the improved X-shaped slot circular polarization antenna in this example changes the internal uniform electric field characteristics by gradually reducing the slot width, so that the slot width at the intersection 11 of the two slots of the X slot is smaller. The slot slot that has been optimized by inscribed design has a stronger radiation current at the slot, and the effective radiation aperture is significantly improved compared with the traditional X-shaped slot unit, so that the slot circular polarization antenna after optimized design has a higher radiation efficiency. In order to improve the polarization characteristics of the antenna and optimize the axial ratio characteristics of the antenna, the two slot slots are not perpendicular to each other, but the angle of the X-shaped slot is fine-tuned by optimization, and the slot slot is rotated counterclockwise around the radiation direction by a certain angle as a whole. In addition, in order to avoid the deterioration of the standing wave characteristics caused by rotation, a small metal column (such as a metal cylinder) is introduced at a certain distance from the center of the slot at the antenna input end to suppress reflection. The improved X-shaped slot circular polarization antenna in this example greatly improves the unit radiation efficiency, and increases the radiation efficiency of the radiation unit of the traditional X-shaped slot circular polarization antenna from about 25% to more than 50%. Therefore, when designing an array antenna, only a few radiating elements are needed to radiate most of the energy in the channel. This design not only reduces the number of elements and the size of the antenna, but also maintains a high overall radiation efficiency. Based on the improved X-shaped slot circularly polarized antenna, this example constructs a 1×4 circularly polarized linear array antenna3. Figure 3 As shown, the antenna is a traveling wave antenna structure, including an input interface 31, four improved X-shaped slot circularly polarized radiation units 32 of the same structure, and a matching load 33. The linear array antenna achieves a simulated radiation efficiency of more than 87% under the condition of only four-unit radiation slots.
[0022] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, and two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.
[0023] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. An improved X-shaped slot circularly polarized antenna, It is characterized in that The improved X-shaped slot circularly polarized antenna is a reduced height waveguide structure, comprising an improved X-shaped slot (1) dug out of the top waveguide wall for radiating energy and an impedance adjuster (2) inside the waveguide for adjusting impedance matching.
2. The improved X-shaped slot circularly polarized antenna according to claim 1, It is characterized in that The height-reduced waveguide structure is a substrate-integrated waveguide structure, comprising upper and lower metal copper-clad surfaces, a dielectric substrate, and two rows of metalized through holes for forming equivalent waveguide narrow walls.
3. The improved X-shaped slot circularly polarized antenna according to claim 1, It is characterized in that The improved X-shaped slot (1) refers to an X-shaped slot groove with uniform slot width that is inscribed internally, and the slot width is gradually reduced by inscription to change the uniform electric field characteristics inside, and the slot width at the intersection (11) of two slots of the X slot is smaller than the width value at both ends of the slot.
4. The improved X-shaped slot circularly polarized antenna according to claim 3, It is characterized in that The X-shaped slot groove is formed by the intersection of two slots with the same slot width and length, and the slot intersection point is the midpoint of the two slots.
5. The improved X-shaped slot circularly polarized antenna according to claim 3, It is characterized in that The two slots of the X-shaped slot do not intersect vertically, and the center line direction of the X-shaped slot is not parallel or vertical to the waveguide transmission direction.
6. The improved X-shaped slot circularly polarized antenna according to claim 3, It is characterized in that The X-shaped slot is rotated counterclockwise around the radiation direction by a preset angle as a whole.
7. The improved X-shaped slot circularly polarized antenna according to claim 3, It is characterized in that The slot intersection point of the X-shaped slot groove is located on one side of the center line of the antenna, and the slot (12) adjacent to the narrow wall of the equivalent metal waveguide is cut off.
8. The improved X-shaped slot circularly polarized antenna according to claim 1, It is characterized in that The impedance adjuster (2) is a metal column at a preset distance from the intersection of the gaps, the metal column passes through the inside of the waveguide, the top surface of the column contacts the top waveguide wall, and the bottom surface of the column contacts the bottom waveguide wall.