Missile-borne low-profile, miniaturized and low-frequency-division-ratio dual-frequency antenna

Abstract

The utility model relates to a missile-borne low-profile, miniaturized and low-frequency-division-ratio dual-frequency antenna, and belongs to the technical field of communication. The dual-frequency antenna comprises a metal bottom plate, an antenna housing fixed with the metal bottom plate, and a dielectric substrate fixed between the metal bottom plate and the antenna housing. Wherein the dielectric substrate comprises an upper-layer dielectric substrate and a lower-layer dielectric substrate which are bonded with each other; metal patches are loaded on the surfaces of the upper-layer dielectric substrate and the lower-layer dielectric substrate; the upper-layer dielectric substrate and the lower-layer dielectric substrate are electrically connected through a metal column located on the central axis of the dielectric substrate, and the lower-layer dielectric substrate and the metal bottom plate are electrically connected through a feed probe located on the central axis; and the metal patches on the surfaces of the upper-layer dielectric substrate and the lower-layer dielectric substrate are horizontally symmetrical along the central axis. According to the utility model, the dual-frequency antenna with low profile, small size and low frequency division ratio is realized, the frequency division ratio is low under the condition that the basic radiation efficiency is guaranteed, and two narrowband working frequency bands can be provided in the s wave band.

Description

TECHNICAL FIELD

[0001] The utility model belongs to communication technical field relates to a missile-borne, easy to conform, low profile, small size, low frequency ratio's dual -frequency antenna. BACKGROUND

[0002] With the rapid development of wireless communication technology, as the core carrier of information transmission, the application scene of antenna has gradually expanded from the traditional ground base station and other large space scenes to aerospace, missile guidance, unmanned aerial vehicle group, Internet of Things terminal and other highly integrated and strong environment constrained fields. In satellite payload, missile-borne communication, airborne radar and other systems, the equipment needs to maintain stable communication under extreme mechanical conditions, and at the same time, limited by the space and aerodynamic shape of the platform, the installation space of the antenna is often compressed to millimeter level. In addition, the complexity of modern electromagnetic environment rises sharply, and the spectrum resources are increasingly crowded due to the intensive multiplexing of 5G / 6G, satellite Internet and military frequency bands. The interference and noise of different frequency bands are superimposed, which puts forward higher requirements on the anti-interference ability and spectrum efficiency of the communication system.

[0003] For traditional antenna design, single frequency antenna usually cannot meet the multi-functional requirements. If multiple antennas are arranged separately, not only the space is occupied, but also electromagnetic coupling interference is caused. Although wideband antenna covers a wide frequency, its wideband receiving characteristics are easily disturbed by out-of-band noise, and it has high power consumption and low efficiency, which is difficult to adapt to small mobile devices. Low frequency ratio dual frequency antenna has become an ideal research object due to its characteristics such as narrowband filtering, spectrum segmentation and compact structure. Through the independent work of two adjacent frequency bands (frequency ratio fH / fL), the anti-interference ability and spectrum utilization rate can be significantly improved, which is especially suitable for high-density communication scenes with tight spectrum resources.

[0004] However, the existing low frequency ratio antenna design still has some limitations. Some researches use single-layer patch multi-mode resonance or branch coupling structure to realize dual frequency by exciting high-order modes, but the frequency ratio is usually large, which is difficult to meet the narrow interval requirement of L / S frequency band. Although etching slots or parasitic patches can compress the frequency ratio, such designs do not have a complete metal ground plane, and when installed in a metal shell, the mirror effect of the ground plane will distort the radiation pattern, causing a sharp drop in gain and impedance mismatch. On the other hand, although stacked multi-frequency antennas can adjust multiple frequency bands through interlayer coupling, their profile is relatively high, which makes it difficult to load the radome for conformal design. Moreover, in order to reduce the interlayer coupling, the patch sizes of different layers are quite different, resulting in a high frequency ratio.

[0005] Under this background, how to design a low profile conformal dual frequency antenna with multi-frequency precise response, strong environmental compatibility and low frequency ratio in a full metal environment and limited space has become a challenge that needs to be broken through for the miniaturization and high performance of current wireless systems. UTILITY MODEL CONTENT

[0006] Therefore, the utility model discloses a kind of missile-borne low profile, miniaturization, low frequency ratio of small size, dual-frequency antenna, and provide multiple operating frequency bands and the mechanical stability and electromagnetic performance stability of antenna are good.

[0007] To achieve the above object, the utility model provides the following technical scheme:

[0008] A kind of missile-borne low profile, miniaturization, low frequency ratio of small size, dual-frequency antenna, it includes metal bottom plate, with the radome of metal bottom plate is fixed and is fixed between the dielectric substrate of metal bottom plate and radome, wherein, dielectric substrate is fixed after with metal bottom plate, radome is fixed with metal bottom plate again, to realize the protection of dielectric substrate.

[0009] The dielectric substrate includes mutually adhered upper layer dielectric substrate and lower layer dielectric substrate, specifically, upper layer dielectric substrate and lower layer dielectric substrate are adhered by an adhesive layer;Upper layer dielectric substrate and lower layer dielectric substrate are loaded with metal patch on surface;The upper layer dielectric substrate and lower layer dielectric substrate are electrically connected by the metal column located on the center axis of dielectric substrate, and the lower layer dielectric substrate and metal bottom plate are electrically connected by the feed probe located on the center axis;The metal patch on the surface of the upper layer dielectric substrate and lower layer dielectric substrate is horizontally symmetrical along the center axis.

[0010] Further, the size of the lower layer dielectric substrate is greater than the size of the upper layer dielectric substrate, and the size of the metal bottom plate is greater than the size of the lower layer dielectric substrate.

[0011] Further, the surface of the upper layer dielectric substrate is loaded with a metal centrifugal circular ring patch and a first fan-shaped metal patch. Wherein, electromagnetic coupling is generated between the metal centrifugal circular ring patch and the first fan-shaped metal patch through the narrow gap of interval, so as to excite the surface of the metal centrifugal circular ring patch to resonate at low frequency.

[0012] In addition, the metal centrifugal circular ring patch is provided with an arc-shaped groove, and the long arc end of the first fan-shaped metal patch faces the arc-shaped groove. The short arc end of the first fan-shaped metal patch is provided with a through hole, which is used for connecting the metal column. Wherein, the arc-shaped groove is symmetrical about the center axis.

[0013] Further, in the upper layer dielectric substrate near the short arc end of the first fan-shaped metal patch, a circular through hole with a diameter of 4mm is opened, and the circular through hole also penetrates the adhesive layer, to reserve space for welding operation of the second fan-shaped metal patch and the feed probe.

[0014] Further, the first surface of the lower layer dielectric substrate is loaded with a first metal open centrifugal circular ring patch, a second metal open centrifugal circular ring patch, a third metal open centrifugal circular ring patch, a crescent metal patch, a second fan-shaped metal patch, and a third fan-shaped metal patch.

[0015] The second metal open centrifugal circular ring patch and the third metal open centrifugal circular ring patch are located inside the first metal open centrifugal circular ring patch, and the opening directions of the three are the same and symmetric about the central axis. In addition, the outer radius of the first metal open centrifugal circular ring patch is smaller than the inner radius of the metal centrifugal circular ring patch.

[0016] The second metal open centrifugal circular ring patch and the third metal open centrifugal circular ring patch are coupled through a gap.

[0017] One end of the second fan-shaped metal patch is located in the opening of the first metal open centrifugal circular ring patch, and the other end is connected with the feed probe and the metal column, respectively.

[0018] The second fan-shaped metal patch and the first metal open centrifugal circular ring patch are coupled through a gap, thereby generating resonance at high frequencies.

[0019] The third fan-shaped metal patch is located between the first metal open centrifugal circular ring patch and the crescent metal patch. The crescent metal patch is extended a certain distance from the thinner side of the first metal open centrifugal circular ring patch through the third fan-shaped metal patch and then coupled through a gap. This way effectively extends the current path length of the high-frequency resonance point, reduces the shielding effect and interlayer coupling of the upper and lower metal patches, reduces the influence of the high-frequency resonance structure on the low-frequency resonance structure, moves the high-frequency resonance point to low frequency, maintains the basic radiation efficiency of the antenna, and effectively reduces the frequency division ratio of the antenna.

[0020] Further, the gaps between the first metal open centrifugal circular ring patch and the second metal open centrifugal circular ring patch, and between the second metal open centrifugal circular ring patch and the third metal open centrifugal circular ring patch are equal.

[0021] Further, the second surface of the lower layer dielectric substrate is loaded with a metal layer.

[0022] Further, the radome is provided with three rectangular grooves for placing the metal bottom plate, the lower layer dielectric substrate, and the upper layer dielectric substrate, respectively. The rectangular grooves that are co-molded with the antenna can make the outer edge of the radome have a thicker thickness from the dielectric substrate, thereby making the radome have better high-temperature resistance.

[0023] In addition, the radome is also provided with a threaded hole for connecting the radome with the projectile.

[0024] The utility model discloses beneficial effect lies in:

[0025] (1) the utility model discloses realized the section low, the size small low frequency ratio of double -frequency antenna, this antenna is under the condition of guaranteeing basic radiation efficiency, and the frequency division is lower, can provide two narrowband operating frequency band in s wave band.

[0026] (2) in the utility model, because the upper and lower layer medium substrate interval is close, the structure of mutual connection is greatly influenced to the coupling of different resonant frequency points, therefore designs the different metal patch through the gap to realize the mutual coupling, and the coupling of the high, low frequency resonant structure between each other can be reduced through the gap coupling mode.

[0027] (3) benefit from the smaller size of double -frequency antenna, when loading antenna cover structure and metal bottom plate, it still has lower section, smaller size, and can pass through the metal screw and fix each part of double -frequency antenna stably on the elastic body, has good mechanical stability.

[0028] (4) the metal patch part of medium substrate surface in double -frequency antenna has a far distance from the side edge of antenna cover, this makes when double -frequency antenna is loaded on the full -metal environment elastic body structure, has stable, good electromagnetic performance.

[0029] (5) the utility model discloses through the metal column and connect first fan -shaped metal patch and second fan -shaped metal patch, and the tail end of second fan -shaped patch is connected with feed probe, benefit from such design, can use a feed probe and excite the radiation patch of upper layer and lower layer simultaneously.In addition, the metal column and feed probe are all arranged on the central axis, and the excitation mode of central symmetry can produce the symmetrical current mode on the ring structure, thereby keeping the polarization mode of different resonant frequency points consistent.

[0030] The other advantages, objects and features of the utility model will be described in the subsequent specification to some extent, and to some extent, it will be obvious to those skilled in the art based on the study of the following text or can be taught from the practice of the utility model. The objects and other advantages of the utility model can be realized and obtained by the following specification. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to make the purpose, technical scheme and advantage of the utility model more clear, the preferred detailed description of the utility model will be described below with reference to the drawings, wherein:

[0032] Figure 1 It is the complete elastic antenna three -dimensional structure schematic diagram of loading antenna cover and metal bottom plate;

[0033] Figure 2 It is double -frequency microstrip antenna three -dimensional structure schematic diagram;

[0034] Figure 3 is a top view of the upper dielectric substrate;

[0035] Figure 4 is a top view of the lower dielectric substrate;

[0036] Figure 5 is a perspective view of the radome;

[0037] Figure 6 is a perspective view of the metal base plate;

[0038] Figure 7 is a top view of the radome;

[0039] Figure 8 is a side view of the radome;

[0040] Figure 9 is a comparison chart of S parameters of the antenna with and without the metal wall;

[0041] Figure 10 is a comparison chart of the standing wave ratio of the antenna with and without the metal wall;

[0042] Figure 11 is a comparison chart of the in-band peak gain curve of the antenna with and without the metal wall;

[0043] Figure 12 is a comparison chart of the radiation direction of the antenna with and without the metal wall at 2.26 GHz and 2.34 GHz when phi = 0°;

[0044] Figure 13 is a comparison chart of the radiation direction of the antenna with and without the metal wall at 2.26 GHz and 2.34 GHz when phi = 90°.

[0045] Reference signs: 1-1. Upper dielectric substrate; 1-2. Metal centrifugal circular ring patch; 1-3. Circular arc groove; 1-4. First fan-shaped metal patch; 1-5. Circular through hole;

[0046] 2-1. Metal column; 2-2. Adhesive layer;

[0047] 3-1. Lower layer dielectric substrate; 3-2. First metal open centrifugal circular ring patch; 3-3. First slit; 3-4. Second slit; 3-5. Second fan-shaped metal patch; 3-6. Second metal open centrifugal circular ring patch; 3-7. Third metal open centrifugal circular ring patch; 3-8. Third fan-shaped metal patch; 3-9. Crescent-shaped metal patch; 3-10. First threaded hole; 3-11. Second threaded hole; 3-12. Third threaded hole; 3-13. Fourth threaded hole; 3-14. Fifth threaded hole; 3-15. Sixth threaded hole; 3-16. Seventh threaded hole; 3-17. Eighth threaded hole; 3-18. Lower layer dielectric substrate back metal layer;

[0048] 4-1. Coaxial feed probe;

[0049] 5-1. First shell mounting threaded hole; 5-2. Second shell mounting threaded hole; 5-3. Third shell mounting threaded hole; 5-4. Fourth shell mounting threaded hole; 5-5. Shell left side arc surface; 5-6. Shell upper edge rectangular surface; 5-7. Shell right side arc surface; 5-8. Shell lower edge rectangular surface; 5-9. Shell bottom edge rectangular square ring surface;

[0050] 6-1. First cylindrical groove; 6-2. Second cylindrical groove; 6-3. Third cylindrical groove; 6-4. Fourth cylindrical groove; 6-5. Fifth cylindrical groove; 6-6. Sixth cylindrical groove; 6-7. Seventh cylindrical groove; 6-8. Eighth cylindrical groove;

[0051] 7-1. First rectangular groove; 7-2. Second rectangular groove; 7-3. Third rectangular groove;

[0052] 8-1. First metal bottom plate mounting threaded hole; 8-2. Second metal bottom plate mounting threaded hole; 8-3. Third metal bottom plate mounting threaded hole; 8-4. Fourth metal bottom plate mounting threaded hole; 8-5. Fifth metal bottom plate mounting threaded hole; 8-6. Sixth metal bottom plate mounting threaded hole; 8-7. Seventh metal bottom plate mounting threaded hole; 8-8. Eighth metal bottom plate mounting threaded hole;

[0053] 9-1. Coaxial feed interface through hole. DETAILED DESCRIPTION

[0054] The following embodiments of the present application will be described in detail with specific examples. Other advantages and effects of the present application can be easily understood by those skilled in the art from the description of the present application. The present application can also be implemented or applied in other different embodiments, and various modifications or changes can be made to the details in the description based on different views and applications without departing from the spirit of the present application. It should be noted that the drawings provided in the following embodiments only schematically illustrate the basic concept of the present application, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0055] The drawings are only used for exemplary illustration, and the representation is only a schematic diagram, not a physical diagram, and cannot be understood as a limitation of the present application; in order to better illustrate the embodiments of the present application, some components in the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product; for those skilled in the art, it is understandable that some known structures and their descriptions in the drawings may be omitted.

[0056] The same or similar reference numerals in the drawings of the embodiments of the present application correspond to the same or similar components; in the description of the present application, it should be understood that if the terms "upper", "lower", "left", "right", "front", "back" and the like indicate the orientation or positional relationship shown in the drawings, only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, therefore the terms describing the positional relationship in the drawings are only used for exemplary illustration, and cannot be understood as a limitation of the present application, for those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0057] Please refer to Figures 1-8 The embodiment provides a missile-borne low-profile, miniaturized, low-frequency ratio dual-frequency antenna, which comprises a radome, a double-layer microstrip antenna and a metal bottom plate, wherein the double-layer microstrip antenna is fixed on the metal bottom plate, the radome is fixed with the metal bottom plate through screws, and the radome covers the double-layer microstrip antenna.

[0058] The inside of the radome is reserved for a first rectangular groove 7-1, a second rectangular groove 7-2 and a third rectangular groove 7-3 for placing a double-layer microstrip antenna and a metal bottom plate, and a first cylindrical groove 6-1 with a diameter of 6 mm and a height of 3 mm, a second cylindrical groove 6-2, a third cylindrical groove 6-3 and a fourth cylindrical groove 6-4 with a diameter of 6 mm and a height of 3 mm are reserved for metal nuts. The radome is fixed by four metal screws, which pass through the first metal bottom plate mounting threaded hole 8-1, the second metal bottom plate mounting threaded hole 8-2, the third metal bottom plate mounting threaded hole 8-3 and the fourth metal bottom plate mounting threaded hole 8-4 on the metal bottom plate from bottom to top, and the first threaded hole 3-10, the second threaded hole 3-11, the third threaded hole 3-12 and the fourth threaded hole 3-13 on the four corners of the dielectric substrate, and finally connected with the fifth cylindrical groove 6-5, the sixth cylindrical groove 6-6, the seventh cylindrical groove 6-7 and the eighth cylindrical groove 6-8 reserved on the radome, and fixed together. In addition, four screw mounting holes are reserved on the radome, including the first housing mounting threaded hole 5-1, the second housing mounting threaded hole 5-2, the third housing mounting threaded hole 5-3 and the fourth housing mounting threaded hole 5-4, which are used for the mutual connection of the radome and the projectile.

[0059] The double-layer microstrip antenna includes an upper layer dielectric substrate 1-1 and a lower layer dielectric substrate 3-1. The material of the upper layer dielectric substrate 1-1 is sj9350, and the material of the lower layer dielectric substrate 3-1 is sj9300. The thicknesses of the two layers of dielectric substrates are consistent, both being 1.016 mm. The upper layer substrate and the lower layer substrate are connected through an adhesive layer, and the material of the adhesive layer is sj930b with a thickness of 0.102 mm.

[0060] The lower layer dielectric substrate 3-1 is larger in size than the upper layer dielectric substrate 1-1. The fifth threaded hole 3-14, the sixth threaded hole 3-15, the seventh threaded hole 3-16 and the eighth threaded hole 3-17 of the lower layer dielectric substrate 3-1 pass through the fifth metal bottom plate mounting threaded hole 8-5, the sixth metal bottom plate mounting threaded hole 8-6, the seventh metal bottom plate mounting threaded hole 8-7 and the eighth metal bottom plate mounting threaded hole 8-8 on the metal bottom plate respectively to fix the metal bottom plate. The eight threaded holes are arranged at the four corners of the lower layer dielectric substrate 3-1, and the metal screws are far away from the radiation patch, which can effectively reduce the influence on the radiation performance.

[0061] The upper surface of the upper layer dielectric substrate 1-1 is provided with a metal centrifugal circular ring patch 1-2 with a large radius for generating low-frequency electromagnetic resonance, and the metal centrifugal circular ring patch 1-2 is connected with the lower layer structure through the first fan-shaped metal patch 1-4. In addition, the metal centrifugal circular ring patch 1-2 is also provided with an arc slot 1-3, and the impedance matching characteristics at low frequency can be adjusted and optimized through this micro-winding structure.

[0062] The second fan-shaped metal patch 3-5 is loaded at the center of the lower dielectric substrate 3-1, the end of the second fan-shaped metal patch 3-5 is connected with the coaxial feeding probe 4-1, and the middle part is connected with the first fan-shaped metal patch 1-4 of the upper dielectric substrate 1-1 through the metal column 2-1, wherein the coaxial feeding probe 4-1 and the metal column 2-1 are located on the central axis of the dielectric substrate. The lower dielectric substrate 3-1 further comprises a nested first metal open centrifugal circular ring patch 3-2, a second metal open centrifugal circular ring patch 3-6, a third metal open centrifugal circular ring patch 3-7 and a crescent-shaped metal patch 3-9. The radius of the first metal open centrifugal circular ring patch 3-2 is smaller than the inner radius of the metal centrifugal circular ring patch 1-2, which is coupled with the second fan-shaped metal patch 3-5 through the first gap 3-3 and the second gap 3-4 to reduce the shielding effect of the metal structure in the upper dielectric substrate, and the shorter current path can produce a resonance point at high frequency. In order to reduce the frequency division ratio, it is necessary to reduce the resonance point at high frequency and keep the resonance point at low frequency as much as possible. The resonance frequency at high frequency can be effectively reduced by coupling the protruding third fan-shaped metal patch 3-8 with the crescent-shaped metal patch 3-9 with a larger radius. The metal structure not shielded by the upper layer can improve the radiation efficiency at high frequency, and the impedance matching at high frequency can also be adjusted by adjusting the opening size of the second metal open centrifugal circular ring patch 3-6 and the third metal open centrifugal circular ring patch 3-7. The bottom of the lower dielectric substrate is a lower dielectric substrate back metal layer 3-18, and the upper and lower dielectric substrates are pressed into a whole through the adhesive layer 2-2. In order to facilitate the welding of the coaxial probe, a circular through hole 1-5 with the same radius is reserved between the upper dielectric substrate and the adhesive layer 2-2.

[0063] The metal patches on the surfaces of the upper and lower dielectric substrates are horizontally symmetrical along the central axis. The symmetrical excitation mode can produce a symmetrical current mode on the ring structure, thereby keeping the polarization mode consistent at different resonance frequency points. In addition, the upper and lower dielectric substrates are close to each other, and the connected structures have a great influence on the coupling of different resonance frequency points. Therefore, the embodiment proposes a nested structure through gap coupling to reduce the coupling between high and low frequency resonance structures.

[0064] In the dual-frequency antenna provided by the embodiment, the arc angles of the first, second and third fan-shaped metal patches are A1×36°, A2=36° and A3=44° respectively. Other parameters of the dual-frequency antenna are shown in Table 1.

[0065] Table 1

[0066]

[0067]

[0068]

[0069] Further, the full model simulation of the dual-band antenna provided in the embodiment is carried out by the electromagnetic simulation software Ansys HFSS. In order to simulate the full metal wall environment of the proposed dual-band antenna at the groove of the projectile body, the left arc surface 5-5 of the shell, the upper edge rectangular surface 5-6 of the shell, the right arc surface 5-7 of the shell, the lower edge rectangular surface 5-8 of the shell and the bottom edge rectangular ring surface 5-9 of the shell are all set as metal surfaces, and the simulation verification is carried out for the two cases of having metal wall and not having metal wall outside the shell.

[0070] As shown in Figure 9 , the S parameter comparison of the dual-band antenna provided in the embodiment under the conditions of loading metal wall and not loading metal wall is shown. It can be seen that the 10dB impedance bandwidth of the dual-band antenna loaded with metal wall is 2253MHz-2267MHz (14M) at low frequency and 2334MHz-2345MHz (11M) at high frequency, and the frequency division ratio is about 1.036. The 10dB impedance bandwidth of the dual-band antenna not loaded with metal wall is 2252MHz-2267MHz (15M) at low frequency and 2334MHz-2346MHz (12M) at high frequency, and the frequency division ratio is about 1.036.

[0071] As shown in Figure 10 , the VSWR comparison of the dual-band antenna provided in the embodiment under the conditions of loading metal wall and not loading metal wall is shown. It can be seen that the bandwidth of the antenna loaded with metal wall whose VSWR is less than 2 is 2253MHz-2267MHz (14M) at low frequency and 2334MHz-2345MHz (11M) at high frequency. The bandwidth of the antenna not loaded with metal wall whose VSWR is less than 2 is 2252MHz-2267MHz (15M) at low frequency and 2334MHz-2346MHz (12M) at high frequency.

[0072] As shown in Figure 11 , the in-band peak gain comparison of the dual-band antenna provided in the embodiment under the conditions of loading metal wall and not loading metal wall is shown. It can be seen that when the antenna is loaded with metal wall, the gain at low frequency is greater than 3.04dB, the peak gain point appears at the center frequency point 2.26GHz at low frequency, the peak gain is 3.84dB, the gain at high frequency is greater than 1.02dB, the peak gain point appears at the center frequency point 2.34GHz at high frequency, and the peak gain is 2.62dB. When the antenna is not loaded with metal wall, the gain at low frequency is greater than 3.14dB, the peak gain point appears at the center frequency point 2.26GHz at low frequency, the peak gain is 3.86dB, the gain at high frequency is greater than 1.2dB, the peak gain point appears at the center frequency point 2.34GHz at high frequency, and the peak gain is 2.74dB.

[0073] As shown in Figure 12Fig. 6 shows the radiation direction comparison between the dual-band antenna with and without the metal wall at 2.26GHz and 2.34GHz when phi=0°, where phi=0° means the cross section parallel to the long side of the dual-band antenna. Figure 12 It can be seen that the peak gain and beam width of the dual-band antenna with and without the metal wall are basically consistent in the main radiation direction, i.e., theta>-30° and theta<30°.

[0074] As shown in Fig. 7, the radiation direction comparison between the dual-band antenna with and without the metal wall at 2.26GHz and 2.34GHz when phi=90°, where phi=90° means the cross section parallel to the short side of the dual-band antenna. Figure 13 It can be seen that the peak gain and beam width of the dual-band antenna with and without the metal wall are basically consistent in the main radiation direction.

[0075] In summary, the dual-band antenna with low profile, miniaturization, and low frequency division ratio proposed by the present application can realize miniaturization, conformability, and good mechanical stability under the condition of limited space, where the profile height of the microstrip antenna is relatively low, only 0.015λ. In addition, the dual-band antenna proposed by the present application can have a relatively low frequency division ratio in the S band, about 1.036. After simulation test, the working frequency band and radiation characteristics of the dual-band antenna remain good stability when the edge is in a full-metal environment, while maintaining good electromagnetic characteristics.

[0076] Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the present application and not to limit it. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the purpose and scope of the present application, which should be covered in the scope of the claims of the present application.

Claims

1. A missile-borne dual-band antenna with low profile, miniaturization and low frequency division ratio, characterized in that, The antenna comprises a metal base plate, a radome fixed to the metal base plate, and a dielectric substrate fixed between the metal base plate and the radome; the dielectric substrate comprises an upper dielectric substrate and a lower dielectric substrate adhered to each other, and the upper dielectric substrate and the lower dielectric substrate are both loaded with metal patches; the upper dielectric substrate and the lower dielectric substrate are electrically connected through a metal column located on a central axis of the dielectric substrate, and the lower dielectric substrate and the metal base plate are electrically connected through a feed probe located on the central axis; the metal patches on the surfaces of the upper dielectric substrate and the lower dielectric substrate are horizontally symmetrical along the central axis.

2. The dual-band antenna according to claim 1, characterized in that, The surface of the upper dielectric substrate is loaded with a metal centrifugal circular ring patch and a first fan-shaped metal patch inside the metal centrifugal circular ring patch; the metal centrifugal circular ring patch and the first fan-shaped metal patch are electromagnetically coupled through a gap therebetween; a through hole is formed at a short arc end of the first fan-shaped metal patch for connecting the metal column.

3. The dual-band antenna according to claim 2, wherein, The metal centrifugal circular ring patch is provided with an arc-shaped groove; a long arc end of the first fan-shaped metal patch faces the arc-shaped groove.

4. The dual-band antenna according to claim 1, wherein, The first surface of the lower dielectric substrate is loaded with a first metal open centrifugal circular ring patch, a second metal open centrifugal circular ring patch, a third metal open centrifugal circular ring patch, a crescent-shaped metal patch, a second fan-shaped metal patch, and a third fan-shaped metal patch; The second metal open centrifugal circular ring patch and the third metal open centrifugal circular ring patch are located inside the first metal open centrifugal circular ring patch, and the opening directions of the three metal open centrifugal circular ring patches are the same; the second metal open centrifugal circular ring patch and the third metal open centrifugal circular ring patch are coupled through a gap therebetween; One end of the second fan-shaped metal patch is located in the opening of the first metal open centrifugal circular ring patch, and the other end is connected with the feed probe and the metal column, respectively; the second fan-shaped metal patch and the first metal open centrifugal circular ring patch are coupled through a gap therebetween; The third fan-shaped metal patch is located between the first metal open centrifugal circular ring patch and the crescent-shaped metal patch; the third fan-shaped metal patch and the crescent-shaped metal patch are coupled through a gap therebetween.

5. The dual-band antenna according to claim 4, wherein, The intervals between the first metal open centrifugal circular ring patch and the second metal open centrifugal circular ring patch and between the second metal open centrifugal circular ring patch and the third metal open centrifugal circular ring patch are equal.

6. The dual-band antenna according to claim 4, wherein, The second surface of the lower dielectric substrate is loaded with a metal layer.

7. The dual-band antenna according to claim 1, wherein, The size of the lower dielectric substrate is greater than that of the upper dielectric substrate, and the size of the metal base plate is greater than that of the lower dielectric substrate.

8. The dual-band antenna according to claim 1, wherein, The radome is provided with three rectangular grooves for placing the metal base plate, the lower dielectric substrate, and the upper dielectric substrate, respectively.

9. The dual-band antenna according to claim 8, wherein, The radome is also provided with a threaded hole for connecting the radome with a projectile.

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