Method for reducing influence of multipath signals on spherical phased-array antenna

Abstract

The invention discloses a method for reducing the influence of a multipath signal on a spherical phased-array antenna, and the method comprises the steps: enabling the spherical phased-array antenna to be composed of a spherical part and an arc part which is integrated with the spherical part, by increasing the included angle between the normal of each array element of the cambered surface part of the spherical phased-array antenna and the horizontal direction, the length of a wave beam sidelobe coverage area of each array element of the cambered surface part is increased, and the interference of multipath signals on an antenna system is reduced. According to the invention, the influence of multipath signals on the spherical phased-array antenna working at a low elevation angle can be reduced without increasing the actual height of the antenna base.

Description

Technical Field

[0001] The invention relates to the technical field of spherical phased array antennas, and in particular to a method for reducing the influence of multipath signals on spherical phased array antennas. Background Art

[0002] Spherical phased array antennas have the technical advantages of using multi-beam working mode and full airspace coverage, and can track and control multiple space targets at the same time. In recent years, they have received increasing attention in the research of new antennas and have become a hot area in the research of new antennas.

[0003] A technical problem encountered in the design of spherical phased array antennas is that spherical phased array antennas are affected by ground multipath signals when working on low-elevation targets. Due to the characteristics of the spherical phased array antenna surface, spherical phased array antennas are more susceptible to the multipath signals caused by ground reflection when working at low elevation angles than traditional parabolic antennas. The impact of this multipath signal will reduce the signal-to-noise ratio of the antenna receiving signal, and in severe cases, it may even cause the antenna system to be unable to receive and demodulate the target signal. Traditionally, the impact of multipath signals when the antenna works at low elevation angles is generally reduced by increasing the height of the spherical phased array antenna base. Theoretically, the greater the height of the antenna base, the smaller the impact of the multipath signal reflected from the bottom surface on the antenna receiving signal. However, since the cost and other issues must be comprehensively considered when designing the antenna system, the height of the spherical phased array antenna base is often a contradiction in the design of the antenna system. Summary of the invention

[0004] In response to the demand for antenna system performance when a spherical phased array antenna system works at a low elevation angle, the present invention proposes a method for reducing the influence of multipath signals on a spherical phased array antenna. The method reduces the influence of multipath signals on the spherical phased array antenna when the spherical phased array antenna works at a low elevation angle without increasing the height of the spherical phased array antenna base. Therefore, the performance of the antenna system can be improved while reducing the design cost of the spherical phased array antenna.

[0005] The present invention discloses a method for reducing the influence of multipath signals on a spherical phased array antenna, which comprises:

[0006] The spherical phased array antenna consists of a spherical part and a curved part integrated with the spherical part. When the spherical phased array antenna works at a low elevation angle, the angle between the normal of each array element of the curved part of the spherical phased array antenna and the horizontal direction is increased to expand the length of the beam sidelobe coverage area of ​​each array element of the curved part, thereby reducing the interference of multipath signals to the antenna system.

[0007] Furthermore, the spherical phased array antenna is located above the antenna base; the spherical portion is located above the arc portion; the arc portion is composed of N layers of array elements stacked in sequence, where N is a positive integer.

[0008] Further, the method of increasing the angle between the normal line of each array element of the curved surface part of the spherical phased array antenna and the horizontal direction to expand the length of the beam sidelobe coverage area of ​​each array element of the curved surface part includes:

[0009] Without increasing the height of the antenna base, the angle between the normal of each array element of the curved surface part of the spherical phased array antenna and the horizontal direction is increased, that is, the length of the area covered by the beam sidelobe of each array element of the curved surface part is increased, so as to achieve the same effect as increasing the height of the antenna base and reducing multipath signal interference.

[0010] Further, obtaining the length of the area covered by the beam sidelobe of each array element of the enlarged arc surface part includes:

[0011] According to the included angle between the normal line of each array element of the enlarged arc surface part and the horizontal direction, the included angle between the beam side lobe of each array element of the enlarged arc surface part and the horizontal direction is obtained;

[0012] According to the included angle between the beam sidelobe of each array element of the enlarged arc surface part and the horizontal direction, the length of the area covered by the beam sidelobe of each array element of the enlarged arc surface part is obtained.

[0013] Further, obtaining the angle between the beam sidelobe of each array element of the enlarged curved surface part and the horizontal direction according to the angle between the normal line of each array element of the enlarged curved surface part and the horizontal direction includes:

[0014] If the angle between the normal of each array element of the enlarged arc surface part and the horizontal direction is ψ, and the main lobe width of the downlink antenna beam of each array element of the arc surface part is 2θ, then the angle between the beam side lobe of each array element of the enlarged arc surface part and the horizontal direction is θ-ψ.

[0015] Furthermore, if the angle between the line connecting the array element at the boundary point between the spherical part and the arc part and the center of the spherical phased array antenna and the horizontal direction is ψ, then the angle between the normal line of each array element of the enlarged arc part and the horizontal direction is ψ.

[0016] Further, obtaining the length of the area covered by the beam sidelobe of each array element of the enlarged curved surface part according to the included angle between the beam sidelobe of each array element of the enlarged curved surface part and the horizontal direction includes:

[0017] The length of the area covered by the beam sidelobe of each array element in the enlarged arc surface part is:

[0018] l′=h×cotan(θ-ψ) (1)

[0019] Wherein, l′ is the length of the area covered by the beam sidelobe of each array element of the enlarged arc surface part, h is the height of the antenna base of the spherical phased array antenna, ψ is the angle between the normal of each array element of the enlarged arc surface part and the horizontal direction, the main lobe width of the downlink antenna beam of each array element of the arc surface part is 2θ, and cotan is the cotangent function.

[0020] Furthermore, the length of the area covered by the beam sidelobe of each array element of the enlarged curved surface portion is greater than the length of the area covered by the beam sidelobe of each array element of the enlarged curved surface portion.

[0021] Further, obtaining the length of the area covered by the beam sidelobe of each array element of the curved surface part before the increase includes:

[0022] The height of the antenna base of the spherical phased array antenna is h. If the arc surface of the spherical phased array antenna is divided into cylindrical surfaces before enlargement, the normal of each array element of the cylindrical surface is parallel to the horizontal direction; if the main lobe width of the downlink antenna beam of each array element of the cylindrical surface is 2θ, the angle between the beam side lobe of each array element of the cylindrical surface and the horizontal direction is θ; the length of the area covered by the beam side lobe of each array element of the cylindrical surface is:

[0023] l=h×cotanθ (2)

[0024] Where l is the length of the area covered by the beam sidelobe of each array element of the cylinder, and cotan is the cotangent function.

[0025] Furthermore, the method of increasing the length of the area covered by the beam sidelobe of each array element of the curved surface portion to achieve the same effect as increasing the height of the antenna base to reduce multipath signal interference includes:

[0026] The length of the area covered by the beam sidelobe of each array element in the enlarged arc surface is l′, which is equivalent to increasing the height of the antenna base:

[0027] h′=l′×tanθ=h×cotan(θ-ψ)×tanθ (3)

[0028] Wherein, h′ is the height of the antenna base after equivalent, h is the height of the antenna base, θ is the half-beam width of the downlink antenna of each array element of the arc surface part, ψ is the angle between the normal of each array element of the enlarged arc surface part and the horizontal direction, tan is the tangent function, and cotan is the cotangent function.

[0029] Due to the adoption of the above technical solution, the present invention has the following advantages:

[0030] 1. The present invention proposes a method for reducing the influence of multipath signals without increasing the height of the antenna base based on the characteristics of the antenna array of the spherical phased array antenna. The method is simple, reliable and easy to implement. It can improve the performance of the antenna system without increasing the design cost of the spherical phased array antenna system. The method can be used to design a spherical phased array antenna system that meets the index requirements in engineering practice. A key problem in the design of a digital multi-beam spherical phased array antenna system is solved.

[0031] 2. Simple implementation, less resource occupation, and reduced system design cost. The present invention does not require complex circuits, and the implementation method is relatively simple. The present invention only uses the original equipment of the system without adding additional equipment, and by changing the layout of the spherical phased array antenna array surface and expanding the length of the sidelobe coverage interval of the array element antenna beam, the virtual antenna base height of the spherical phased array antenna is increased, thereby reducing the interference of multipath signals on the antenna system. Reduce the design cost of the antenna system. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0033] Figure 1 It is a structural schematic diagram of the antenna array surface of a traditional spherical phased array antenna.

[0034] Figure 2 It is a structural diagram of the spherical phased array antenna system sending and receiving signals.

[0035] Figure 3 It is the beam pattern of the element antenna of the spherical phased array antenna system receiving the downlink signal.

[0036] Figure 4 It is a schematic diagram of the analysis of multipath signal interference of traditional spherical phased array antenna.

[0037] Figure 5 It is a schematic diagram of the structure of the antenna array surface of a spherical phased array antenna that reduces the influence of multipath signals.

[0038] Figure 6 It is a schematic diagram of the analysis of multipath signal interference of spherical phased array antenna after adopting improvement measures.

[0039] Figure 7 It is a schematic diagram of the analysis of the equivalent antenna base height of the spherical phased array antenna after adopting the improved measures. DETAILED DESCRIPTION

[0040] The present invention is further described in conjunction with the accompanying drawings and embodiments, and the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field should fall within the scope of protection of the embodiments of the present invention.

[0041] Traditionally, spherical phased array antennas generally use the method of increasing the height of the antenna base to reduce the impact of multipath signals reflected from the ground on the signals received by the antenna system when the spherical phased array antenna is working at low elevation angles. Since this method of processing multipath signals is limited by factors such as the design cost of the antenna system and the antenna deployment space, the base height of the antenna system design often cannot meet the requirements of the antenna system performance, and a contradiction arises between the antenna system performance and the antenna design cost. This application proposes a method for reducing the impact of multipath signals without increasing the height of the antenna base based on the characteristics of the antenna array surface of a spherical phased array antenna. This method is simple, reliable and easy to implement, and can improve the performance of the antenna system without increasing the design cost of the spherical phased array antenna system. This method can be used to design a spherical phased array antenna system that meets the index requirements in engineering practice.

[0042] The present invention provides an embodiment of a method for reducing the influence of multipath signals by a spherical phased array antenna, which comprises:

[0043] The spherical phased array antenna consists of a spherical part and a curved part integrated with the spherical part. When the spherical phased array antenna works at a low elevation angle, the angle between the normal of each array element of the curved part of the spherical phased array antenna and the horizontal direction is increased to expand the length of the beam sidelobe coverage area of ​​each array element of the curved part, thereby reducing the interference of multipath signals to the antenna system.

[0044] In one embodiment of the present application, the spherical phased array antenna is located above the antenna base; the spherical portion is located above the arc portion; the arc portion is composed of N layers of array elements stacked in sequence, where N is a positive integer.

[0045] In one embodiment of the present application, the step of increasing the angle between the normal of each array element of the curved surface portion of the spherical phased array antenna and the horizontal direction to expand the length of the beam sidelobe coverage area of ​​each array element of the curved surface portion includes:

[0046] Without increasing the height of the antenna base, the angle between the normal of each array element of the curved surface part of the spherical phased array antenna and the horizontal direction is increased, that is, the length of the area covered by the beam sidelobe of each array element of the curved surface part is increased, so as to achieve the same effect as increasing the height of the antenna base and reducing multipath signal interference.

[0047] In one embodiment of the present application, obtaining the length of the area covered by the beam sidelobe of each array element of the enlarged curved surface part includes:

[0048] According to the included angle between the normal line of each array element of the enlarged arc surface part and the horizontal direction, the included angle between the beam side lobe of each array element of the enlarged arc surface part and the horizontal direction is obtained;

[0049] According to the included angle between the beam sidelobe of each array element of the enlarged arc surface part and the horizontal direction, the length of the area covered by the beam sidelobe of each array element of the enlarged arc surface part is obtained.

[0050] In one embodiment of the present application, obtaining the angle between the beam sidelobe of each array element of the enlarged curved surface portion and the horizontal direction according to the angle between the normal line of each array element of the enlarged curved surface portion and the horizontal direction includes:

[0051] If the angle between the normal of each array element of the enlarged arc surface part and the horizontal direction is ψ, and the main lobe width of the downlink antenna beam of each array element of the arc surface part is 2θ, then the angle between the beam side lobe of each array element of the enlarged arc surface part and the horizontal direction is θ-ψ.

[0052] In one embodiment of the present application, obtaining the length of the area covered by the beam sidelobe of each array element of the enlarged curved surface portion according to the angle between the beam sidelobe of each array element of the enlarged curved surface portion and the horizontal direction includes:

[0053] The length of the area covered by the beam sidelobe of each array element in the enlarged arc surface part is:

[0054] l′=h×cotan(θ-ψ) (1)

[0055] Wherein, l′ is the length of the area covered by the beam sidelobe of each array element of the enlarged arc surface part, h is the height of the antenna base of the spherical phased array antenna, ψ is the angle between the normal of each array element of the enlarged arc surface part and the horizontal direction, the main lobe width of the downlink antenna beam of each array element of the arc surface part is 2θ, and cotan is the cotangent function.

[0056] In one embodiment of the present application, the length of the area covered by the beam sidelobe of each array element of the enlarged curved surface portion is greater than the length of the area covered by the beam sidelobe of each array element of the enlarged curved surface portion.

[0057] In one embodiment of the present application, obtaining the length of the area covered by the beam sidelobe of each array element of the curved surface part before the increase includes:

[0058] The height of the antenna base of the spherical phased array antenna is h. If the arc surface of the spherical phased array antenna is divided into cylindrical surfaces before enlargement, the normal of each array element of the cylindrical surface is parallel to the horizontal direction; if the main lobe width of the downlink antenna beam of each array element of the cylindrical surface is 2θ, the angle between the beam side lobe of each array element of the cylindrical surface and the horizontal direction is θ; the length of the area covered by the beam side lobe of each array element of the cylindrical surface is:

[0059] l=h×cotanθ (2)

[0060] Where l is the length of the area covered by the beam sidelobe of each array element of the cylinder, and cotan is the cotangent function.

[0061] The antenna array of a spherical phased array antenna is generally designed according to the spherical surface plus the cylindrical surface, in which the cylindrical surface is designed for the antenna to work at low elevation angles, and the multipath interference signal is composed of the signal reflected from the ground. Therefore, when the spherical phased array antenna works at a low elevation angle, the multipath signal interference signal received by the antenna is mainly the signal received by the antenna elements on these cylindrical surfaces. The amplitude of the signal received by the element antenna of the spherical phased array antenna is related to the main beam width of the element antenna. Therefore, the layout of the spherical phased array antenna surface can be changed. By expanding the length of the sidelobe coverage interval of the element antenna beam, the height of the virtual antenna base of the spherical phased array antenna can be increased, thereby reducing the interference of multipath signals on the antenna system. Through this method, the performance of the spherical phased array antenna system can be improved without increasing the design cost of the spherical phased array antenna system, and a spherical phased array antenna system that meets the index requirements can be designed in engineering practice.

[0062] In one embodiment of the present application, the length of the area covered by the beam sidelobe of each array element of the curved surface portion is increased to achieve the same effect as increasing the height of the antenna base to reduce multipath signal interference, including:

[0063] The length of the area covered by the beam sidelobe of each array element in the enlarged arc surface is l′, which is equivalent to increasing the height of the antenna base:

[0064] h′=L′×tanθ=H×cotan(θ-ψ)×tanθ (3)

[0065] Wherein, H′ is the height of the antenna base after equivalent, H is the height of the antenna base, θ is the half beam width of the downlink antenna of each array element of the arc surface part, ψ is the angle between the normal of each array element of the enlarged arc surface part and the horizontal direction, tan is the tangent function, and cotan is the cotangent function.

[0066] In the above embodiment, it should be noted that increasing specifically refers to increasing the angle between the normal of each array element of the arc surface part of the spherical phased array antenna and the horizontal direction.

[0067] For ease of understanding, the present invention provides a more specific embodiment:

[0068] See also Figure 1 ,like Figure 1 As shown in the figure, the traditional spherical phased array antenna adopts a spherical plus cylindrical array layout method, where the spherical surface is half of a standard sphere, and the cylindrical surface is a natural transition of the hemisphere. The purpose of using the spherical plus cylindrical array layout method is to ensure that the spherical phased array antenna can complete the formation of the receiving and transmitting beams for the space target with an elevation angle of 0 to 90 degrees, so as to complete the antenna's receiving and transmitting signals to the target. The cylindrical part of the array mainly participates in the formation of the antenna's receiving and transmitting beams for the low-elevation target, so the interference of multipath signals to the spherical phased array antenna is also mainly introduced by the cylindrical part of the array.

[0069] See also Figure 2 and Figure 3 ,like Figure 2 As shown in the figure, the downlink of the spherical phased array antenna system mainly includes array element antenna, duplexer, T / R component and digital beam forming unit. The spherical phased array antenna system receives the downlink signal of the target through the array element antenna on the antenna array surface, and sends it to the digital beam forming unit after passing through the duplexer and T / R component. Finally, the downlink beam signal of the target is formed in the digital beam forming unit according to the downlink beam forming algorithm, and finally the downlink beam signal is sent to the back-end information processing system for processing.

[0070] Since the multipath interference signal is also received by the array antenna, the characteristics of the array antenna itself must be taken into account in the analysis of the impact of multipath signals on the antenna system: the received signal is the largest in the main lobe of the array antenna's downlink antenna beam, while in the side lobes of the array antenna's downlink antenna beam, the signal is suppressed by the antenna's own side lobes, so the received signal amplitude will be significantly reduced. Figure 3 As shown in the figure, the horizontal axis represents the deviation angle of the downlink beam of the array element antenna in degrees, and the vertical axis represents the amplitude of the downlink beam signal of the array element antenna in dB. The 0 point on the horizontal axis represents that the beam of the array element antenna is pointing directly at the target, and its main lobe is within the range of ±θ centered on the beam pointing, where θ represents the half beam width of the array element antenna, for example, the main lobe of the array element antenna is ±45°. As shown in the figure, the amplitude of the downlink signal received by the array element antenna within the main lobe range of the antenna is a relatively smooth curve, and after exceeding the main lobe range, the signal amplitude received by the array element antenna will drop sharply. Therefore, only the multipath interference signal received by the array element antenna within the main lobe range of the antenna beam needs to be considered, while the multipath interference signal on the side lobe of the antenna can be ignored due to the side lobe suppression of the antenna itself.

[0071] See also Figure 4,Since the multipath interference signal of the spherical phased array antenna is formed by the signal reflected from the ground, according to the above analysis, the impact of the multipath signal on the spherical phased array antenna is mainly caused by the multipath signal reflected from the bottom surface when the antenna works at a low elevation angle, while the interference of the multipath signal on the antenna will be significantly reduced when the antenna elevation angle is high. Therefore, for the traditional spherical phased array antenna, the multipath interference signal received by the element antenna on the cylindrical surface can be analyzed.

[0072] like Figure 4 As shown in the figure, the antenna base height of the traditional spherical phased array antenna is H, and the axis of the element antenna on the cylindrical surface of the spherical phased array antenna is parallel to the horizontal direction. If the main lobe width of the designed downlink antenna beam of the element antenna is ±θ, then the angle between the side lobe of the element antenna and the horizontal direction is θ. Therefore, the length L of the area covered by the side lobe of the element antenna beam is:

[0073] L=H×cotanθ (1)

[0074] Where cotan is the cotangent function.

[0075] Since the multipath signals reflected by the ground in the area covered by the side lobes of the element antenna beam are on the side lobes of the spherical phased array antenna, according to the above analysis, the interference of the multipath interference signals in this area to the spherical phased array antenna can be ignored. According to formula (1), if the height of the antenna base is increased, that is, the value of H is increased, the value of l will also increase accordingly, that is, the area covered by the side lobes of the element antenna beam is increased. This is the basic principle that increasing the height of the spherical phased array antenna base can reduce multipath signal interference.

[0076] Conversely, if the area covered by the beam sidelobe of the array element antenna is increased without increasing the height of the antenna base, the effect of reducing multipath signal interference equivalent to increasing the height of the spherical phased array antenna base can also be achieved. This is the basic idea of ​​the present invention.

[0077] See also Figure 5 and Figure 6 ,like Figure 5 As shown, the array layout method of the traditional spherical phased array antenna of the spherical surface plus the cylindrical surface is changed, and the angle between the line connecting the center of the circle on the spherical surface and the horizontal plane is ψ as a transition zone, and the new array layout method of the spherical phased array antenna is formed by the method of spherical surface plus inclined surface, wherein the angle between the vertical line on the inclined surface and the horizontal plane is ψ.

[0078] like Figure 6As shown in the figure, the antenna base height of the spherical phased array antenna according to the new array layout is also h. The angle between the axis of the element antenna on the inclined plane of the spherical phased array antenna and the horizontal direction is ψ. If the main lobe width of the downlink antenna beam of the designed element antenna is 2θ, the angle between the side lobe of the element antenna and the horizontal direction is θ-ψ. Therefore, the length l′ of the area covered by the side lobe of the element antenna beam is:

[0079] l′=h×cotan(θ-ψ) (2)

[0080] Where cotan is the cotangent function.

[0081] Comparing formula (1) and formula (2), for the same element antenna half-beam width θ and antenna base height h, the length l′ of the area covered by the beam sidelobe of the element antenna of the spherical phased array antenna with the new array layout is obviously greater than the length l of the area covered by the beam sidelobe of the element antenna of the traditional spherical phased array antenna.

[0082] For example, assuming that the half-beam width of the element antenna is θ=45°, and the angle between the vertical line on the inclined plane and the horizontal plane is ψ=20°, then according to formula (1), we can get l=h×cotan(45°)=h, and according to formula (2), we can get l′=h×cotan(25°)=2.14×h. That is, by improving the layout of the array surface of the spherical phased array antenna, the length l′ of the area covered by the beam sidelobe of the element antenna of the spherical phased array antenna is increased to 2.14 times the length l of the area covered by the beam sidelobe of the element antenna of the traditional spherical phased array antenna, thereby significantly reducing the interference of multipath signals.

[0083] See also Figure 7 , since the effect of increasing the area length covered by the beam sidelobe of the element antenna by using the improved array layout method is consistent with the effect of increasing the area length covered by the beam sidelobe of the element antenna by increasing the antenna base height of the traditional spherical phased array antenna. Therefore, the antenna base height of the element antenna equivalent to the traditional spherical phased array antenna can be calculated based on the area length l' covered by the beam sidelobe of the element antenna of the spherical phased array antenna after the improved array layout, and the calculation method is as follows:

[0084] h′=l′×tanθ=h×cotan(θ-ψ)×tanθ (3)

[0085] Where h is the height of the antenna base, θ is the half-beam width of the array element antenna, and ψ is the angle between the vertical line on the inclined plane of the improved array layout and the horizontal plane.

[0086] For example, assuming that the half-beam width of the element antenna is θ=45°, and the angle between the vertical line on the inclined plane and the horizontal plane is ψ=20°, then according to formula (3), h′=h×cotan(25°)×an(45°)=2.14×h, that is, by improving the layout of the array surface of the spherical phased array antenna, it is equivalent to raising the antenna base height to 2.14 times the original antenna base height.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for reducing the influence of multipath signals on a spherical phased array antenna, characterized in that: include: The spherical phased array antenna consists of a spherical part and a curved part integrated with the spherical part. When the spherical phased array antenna works at a low elevation angle, the angle between the normal of each array element of the curved part of the spherical phased array antenna and the horizontal direction is increased to expand the length of the beam sidelobe coverage area of ​​each array element of the curved part, thereby reducing the interference of multipath signals to the antenna system.

2. The method according to claim 1, characterized in that The spherical phased array antenna is located above the antenna base; the spherical part is located above the arc surface part; the arc surface part is composed of N layers of array elements stacked in sequence, where N is a positive integer.

3. The method according to claim 1, characterized in that The method of increasing the angle between the normal line of each array element of the curved surface part of the spherical phased array antenna and the horizontal direction to expand the length of the beam sidelobe coverage area of ​​each array element of the curved surface part includes: Without increasing the height of the antenna base, the angle between the normal of each array element of the curved surface part of the spherical phased array antenna and the horizontal direction is increased, that is, the length of the area covered by the beam sidelobe of each array element of the curved surface part is increased, so as to achieve the same effect as increasing the height of the antenna base and reducing multipath signal interference.

4. The method according to claim 3, characterized in that The length of the area covered by the beam sidelobe of each array element of the enlarged arc surface part is obtained, including: According to the included angle between the normal line of each array element of the enlarged arc surface part and the horizontal direction, the included angle between the beam side lobe of each array element of the enlarged arc surface part and the horizontal direction is obtained; According to the included angle between the beam sidelobe of each array element of the enlarged arc surface part and the horizontal direction, the length of the area covered by the beam sidelobe of each array element of the enlarged arc surface part is obtained.

5. The method according to claim 4, characterized in that The step of obtaining the angle between the beam sidelobe of each array element of the enlarged curved surface part and the horizontal direction according to the angle between the normal line of each array element of the enlarged curved surface part and the horizontal direction comprises: If the angle between the normal of each array element of the enlarged arc surface part and the horizontal direction is θ, and the main lobe width of the downlink antenna beam of each array element of the arc surface part is 2θ, then the angle between the beam side lobe of each array element of the enlarged arc surface part and the horizontal direction is θ-ψ.

6. The method according to claim 5, characterized in that If the angle between the line connecting the array element at the boundary point between the spherical part and the arc part and the center of the spherical phased array antenna and the horizontal direction is ψ, then the angle between the normal line of each array element of the enlarged arc part and the horizontal direction is .

7. The method according to claim 4, characterized in that The step of obtaining the length of the area covered by the beam sidelobe of each array element of the enlarged curved surface part according to the included angle between the beam sidelobe of each array element of the enlarged curved surface part and the horizontal direction comprises: The length of the area covered by the beam sidelobe of each array element in the enlarged arc surface part is: l′=h×cotan(θ-ψ) (1) Wherein, l′ is the length of the area covered by the side lobe of each array element of the enlarged arc surface part, h is the height of the antenna base of the spherical phased array antenna, ψ is the angle between the normal of each array element of the enlarged arc surface part and the horizontal direction, and the main lobe width of the downlink antenna beam of each array element of the arc surface part is 2θ, co ta n is the cotangent function.

8. The method according to any one of claims 1 to 7, characterized in that: The length of the area covered by the beam side lobe of each array element of the enlarged curved surface part is greater than the length of the area covered by the beam side lobe of each array element of the curved surface part before the enlargement.

9. The method according to claim 8, characterized in that Obtaining the length of the area covered by the beam sidelobe of each array element of the curved surface part before the enlargement includes: The height of the antenna base of the spherical phased array antenna is h. If the arc surface of the spherical phased array antenna is divided into cylindrical surfaces before enlargement, the normal of each array element of the cylindrical surface is parallel to the horizontal direction; if the main lobe width of the downlink antenna beam of each array element of the cylindrical surface is 2θ, the angle between the beam side lobe of each array element of the cylindrical surface and the horizontal direction is θ; the length of the area covered by the beam side lobe of each array element of the cylindrical surface is: l=h×cotanθ (2) Where l is the length of the area covered by the beam sidelobe of each array element of the cylinder, and cotan is the cotangent function.

10. The method according to claim 3, characterized in that The method of increasing the length of the area covered by the beam sidelobe of each array element of the arc surface portion to achieve the same effect as increasing the height of the antenna base to reduce multipath signal interference includes: The length of the area covered by the beam sidelobe of each array element in the enlarged arc surface is l′, which is equivalent to increasing the height of the antenna base: h′=l′×tanθ=h×cotan(θ-mountain)×tanθ (3) Wherein, h′ is the height of the antenna base after equivalent, h is the height of the antenna base, θ is the half-beam width of the downlink antenna of each array element of the arc surface part, shan is the angle between the normal of each array element of the enlarged arc surface part and the horizontal direction, tan is the tangent function, and cotan is the cotangent function.

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