MIMO substrate integrated antenna system with directional diagram conformal and cross polarization suppression characteristics

Abstract

The MIMO substrate integrated antenna system comprises an upper substrate, a lower substrate, a dielectric resonator and a decoupling structure, the upper substrate and the lower substrate are respectively provided with a top plane and a reference ground plane, the upper surface of the lower substrate and the lower surface of the upper substrate are oppositely jointed, and the dielectric resonator is arranged on the dielectric resonator. The dielectric resonator is arranged on the upper surface of the upper-layer substrate, the decoupling structure is arranged on the upper-layer substrate, and the decoupling structure and the reference ground plane jointly form a loop. Through the arrangement of the decoupling structure, decoupling between the dielectric antenna units is realized, no extra cross polarization component is introduced, the cross polarization of a radiation pattern is kept at a low level, and pattern conformality and cross polarization suppression are realized; the space occupation of the decoupling structure is small, so that the overall space occupation of the MIMO substrate integrated antenna system is small, and the miniaturization of the MIMO substrate integrated antenna system is facilitated. The antenna is widely applied to the technical field of antennas.

Description

Technical Field

[0001] The present invention relates to the technical field of antennas, and in particular to a MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics. Background Art

[0002] Modern wireless communication systems widely use MIMO technology to increase the total channel capacity by deploying a plurality of antennas at the transmitting and receiving ends, thereby improving the data transmission rate. The increasing number of antennas in base stations and terminals is one of the trends in the development of wireless communication systems. However, requirements such as reducing the base station deployment cost and miniaturizing the terminal require adding more antennas within a limited area. This reduces the antenna spacing and increases the coupling between antennas.

[0003] In a MIMO antenna system, the enhancement of the coupling between antenna elements, that is, the reduction of the isolation degree, will lead to the loss of system performance: on the one hand, the low isolation degree will increase the element correlation and reduce the channel independence, thereby reducing the system throughput; on the other hand, the coupling changes the radiation characteristics of the antenna elements, distorts the antenna radiation pattern, and further deteriorates the spatial coverage of the MIMO antenna system. Summary of the Invention

[0004] Aiming at the technical problems such as low isolation degree between antenna elements and pattern distortion faced by the current MIMO antenna system, the purpose of the present invention is to provide a MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics.

[0005] An embodiment of the present invention includes a MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics, and the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics includes:

[0006] An upper substrate (1000); a top layer plane (1010) is provided on the upper surface of the upper substrate (1000);

[0007] A lower substrate (2000); a reference ground plane (2010) is provided on the upper surface of the lower substrate (2000), and the upper surface of the lower substrate (2000) is relatively joined to the lower surface of the upper substrate (1000);

[0008] A dielectric resonator; the dielectric resonator is provided in the substrate dielectric of the upper substrate (1000);

[0009] A decoupling structure; the decoupling structure is provided on the upper substrate (1000), and the decoupling structure and the reference ground plane (2010) together form a loop.

[0010] Further, both the top layer plane (1010) and the reference ground plane (2010) are copper-clad layers.

[0011] Further, the dielectric resonator includes a first dielectric antenna unit (1020) and a second dielectric antenna unit (1021), and there is no gap between the first dielectric antenna unit (1020) and the second dielectric antenna unit (1021).

[0012] Further, the decoupling structure includes a rectangular metal patch (1100) and a pair of metal vias (1090);

[0013] The rectangular metal patch (1100) is disposed on the upper surface of the upper substrate (1000), and the projection of the interface between the rectangular metal patch (1100) and the first dielectric antenna unit (1020) and the second dielectric antenna unit (1021) coincides;

[0014] One end of the pair of metal vias (1090) is electrically connected to both ends of the rectangular metal patch (1100), the pair of metal vias (1090) passes through the upper substrate (1000), and the other end of the pair of metal vias (1090) is electrically connected to the reference ground plane (2010).

[0015] Further, an opening (1050) is provided in a portion of the top layer plane (1010) corresponding to the projection of the dielectric resonator;

[0016] The upper substrate (1000) is provided with a plurality of air vias (1030) and a plurality of first metal vias (1040);

[0017] Each of the air vias (1030) is arranged inside along the edge of the opening (1050);

[0018] Each of the first metal vias (1040) is arranged outside along the edge of the opening (1050).

[0019] Further, the dielectric resonator is provided with a plurality of second metal vias (1080);

[0020] Each of the second metal vias (1080) is distributed at the corners of the first dielectric antenna unit (1020) and the corners of the second dielectric antenna unit (1021);

[0021] A plurality of mounting metal vias (1060) are provided at the corners of the upper substrate (1000);

[0022] A plurality of ground metal vias (1070) distributed in a grid pattern are provided around the upper substrate (1000).

[0023] Furthermore, the reference ground plane (2010) is provided with a first slot (2020) and a second slot (2021);

[0024] The first slot (2020) is located at the center of the vertical projection of the first dielectric antenna element (1020), and the second slot (2021) is located at the center of the vertical projection of the second dielectric antenna element (1021).

[0025] Furthermore, the first slot (2020) and the second slot (2021) are perpendicular to the projection of the rectangular metal patch (1100).

[0026] Furthermore, the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics further includes:

[0027] A first interface (2040) and a second interface (2041); the first interface (2040) and the second interface (2041) are installed on the lower surface of the lower substrate (2000);

[0028] A first microstrip line (2030) and a second microstrip line (2031); the first microstrip line (2030) and the second microstrip line (2031) are arranged on the lower surface of the lower substrate (2000); one end of the first microstrip line (2030) is connected to the first interface (2040), and the second microstrip line (2031) is connected to the second interface (2041); the first microstrip line (2030) passes through the projection of the first dielectric antenna element (1020), and the second microstrip line (2031) passes through the projection of the second dielectric antenna element (1021); the first microstrip line (2030) is parallel to the second microstrip line (2031).

[0029] Furthermore, the first microstrip line (2030) intersects and is perpendicular to the projection of the first slot (2020);

[0030] The second microstrip line (2031) intersects and is perpendicular to the projection of the second slot (2021).

[0031] The beneficial effects of the present invention are as follows: In the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics in the embodiment, by setting the decoupling structure, the decoupling between the dielectric antenna elements is realized, and no additional cross-polarization components are introduced, so that the cross-polarization of the radiation pattern remains at a low level, realizing pattern conformal and cross-polarization suppression; the space occupied by the decoupling structure is small, making the overall space occupied by the MIMO substrate integrated antenna system small, which is beneficial to the miniaturization of the MIMO substrate integrated antenna system. Description of the Drawings

[0032] Figure 1 Exploded view of the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics in the embodiment;

[0033] Figure 2 Side view of the MIMO substrate integrated antenna system in the embodiment;

[0034] Figure 3 Bottom view of the MIMO substrate integrated antenna system in the embodiment;

[0035] Figure 4 Top view of the MIMO substrate integrated antenna system in the embodiment;

[0036] Figure 5 Schematic diagram of the position of the decoupling structure in the embodiment;

[0037] Figure 6 Schematic diagram of the position of the air vias in the embodiment;

[0038] Figure 7 Schematic diagram of the position of the first metal vias in the embodiment;

[0039] Figure 8 Schematic diagram of the position of the second metal vias in the embodiment;

[0040] Figure 9 Schematic diagram of the working principle of the MIMO substrate integrated antenna system in the embodiment;

[0041] Figure 10 Schematic diagram of the measured and simulated scattering parameter results of the antenna of the MIMO substrate integrated antenna system in the embodiment;

[0042] Figure 11 Schematic diagram of the comparison between the measured and simulated radiation patterns of the MIMO substrate integrated antenna system at 24.125 GHz in the embodiment;

[0043] Figure 12 Schematic diagram of the comparison between the measured and simulated gains of the antenna of the MIMO substrate integrated antenna system in the embodiment;

[0044] Figure 13 Schematic diagram of the comparison of the envelope correlation coefficient of the antenna simulation of the MIMO substrate integrated antenna system with and without decoupling in the embodiment. Detailed implementation manners

[0045] The main objective of antenna decoupling is to improve the antenna port isolation, that is, to reduce the coupling energy. To achieve antenna decoupling, it can be realized through the following three technical routes:

[0046] Technical Route 1 - Hindering the propagation of coupled energy: A decoupling structure that hinders the propagation of coupled energy is set between antenna elements, that is, it absorbs or reflects the coupled energy, reducing the coupled energy reaching the ports of other antenna elements;

[0047] Technical Route 2 - Introducing additional coupled paths to neutralize coupled energy: Between or around antenna elements, or in the antenna feeding structure, a decoupling structure that guides coupled energy is added to introduce new coupled paths; Electromagnetic waves cancel each other out and superimpose at other antenna ports through each path, reducing the coupled energy reaching the ports of other antenna elements;

[0048] Technical Route 3 - Utilizing the superposition of multiple antenna modes to eliminate coupled energy: It is divided into two cases. One is to excite two or more operating modes of the antenna itself, and the electromagnetic fields of each mode cancel each other out and superimpose at other antenna elements, reducing the coupled energy reaching the ports of other antenna elements, which is also called self-decoupling; The other is to add a decoupling structure that introduces additional resonant electromagnetic fields between or around antenna elements, and the electromagnetic fields of the antenna itself and the additionally introduced ones cancel each other out and superimpose at other antenna elements, reducing the coupled energy reaching the ports of other antenna elements.

[0049] The above three technical routes solve the port isolation problem (port decoupling) based on different principles of eliminating coupled energy. However, it is difficult to achieve radiation pattern decoupling for Technical Route 1 and Technical Route 2, while Technical Route 3 can achieve the design of radiation pattern decoupling.

[0050] Therefore, Technical Route 3 can be considered. However, although Technical Route 3 solves the problem of antenna coupling, if not properly handled, it is prone to introduce the following problems (these problems also exist in Technical Route 1 and Technical Route 2):

[0051] 1. For the technology of introducing a decoupling structure, setting a decoupling structure between antennas increases the spacing between antenna elements, and setting a decoupling structure around the antenna requires additional space. This type of technology increases the area required for the antenna, restricting the miniaturization of the system and the improvement of integration;

[0052] 2. Adding a decoupling structure in the antenna and its feeding structure increases the complexity of system design and reduces the radiation efficiency of the antenna;

[0053] 3. Mainly focusing on reducing coupled energy changes the original operating mode of the excited antenna, deforming and deteriorating the antenna radiation pattern, having a negative impact on the coverage range of the system. To make up for the change in the coverage range by increasing the antenna transmission power will increase the system power consumption;

[0054] 4. Adding a decoupling structure introduces additional resonant electromagnetic fields, which is prone to introducing new components in the cross-polarization direction as well, reducing the cross-polarization performance of the antenna, causing interference to itself or other systems, and restricting the polarization diversity effect of the system.

[0055] In view of the characteristics and deficiencies of the above technical route, in this embodiment, a MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics is provided. The structure of the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics is as shown in Figure 1 , Figure 2 and Figure 3 . Among them, Figure 1 is an exploded view of the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics, Figure 2 is a side view of the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics, Figure 3 is a bottom view of the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics.

[0056] Referring to Figure 1 , Figure 2 and Figure 3 , the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics includes components such as an upper substrate (1000), a lower substrate (2000), a dielectric resonator, and a decoupling structure. Among them, both the upper substrate (1000) and the lower substrate (2000) are PCB (Printed Circuit Board) substrates, and their lengths are both l g , the width is w g . The dielectric material of the upper substrate (1000) is Rogers RT / duroid 6010.2LM, and the thickness is t 1 . The dielectric material of the lower substrate (2000) is Rogers RO4003C, and the thickness is t 2 .

[0057] In this embodiment, the upper substrate (1000) includes two surfaces, an upper surface and a lower surface, and the lower substrate (2000) also includes two surfaces, an upper surface and a lower surface. Among them, the upper surface is the upward surface in Figure 1 and Figure 2 , and the lower surface is the surface in Figure 1 and Figure 2The downward-facing surface among them. The "upper" and "lower" only define the relative positional relationship in a specific state, and do not limit that the upper substrate (1000) must be on top and the upper surface must face upward. For example, when actually using the MIMO substrate integrated antenna system, the spatial attitude of the MIMO substrate integrated antenna system can be adjusted so that the upper substrate (1000) is located below the lower substrate (2000). In this way, the upper surfaces of the upper substrate (1000) and the lower substrate (2000) both face downward, and the lower surfaces of the upper substrate (1000) and the lower substrate (2000) both face upward.

[0058] Referring to Figure 1 、 Figure 2 and Figure 3 , a copper-clad layer is provided on the upper surface of the upper substrate (1000) to form the top layer plane (1010); a copper-clad layer is provided on the upper surface of the lower substrate (2000) to form the reference ground plane (2010). Among them, Figure 3 Part (a) of Figure 3 shows the distribution and dimensions of each component when looking at the lower substrate (2000), and part (b) shows the distribution of the copper-clad layer, that is, the reference ground plane (2010), when looking at the lower substrate (2000).

[0059] Referring to Figure 1 and Figure 2 , the upper surface of the lower substrate (2000) faces the lower surface of the upper substrate (1000), and the upper substrate (1000) and the lower substrate (2000) are fixedly joined together by means of mechanical fixing or gluing, etc. In this way, the reference ground plane (2010) is sandwiched between the upper substrate (1000) and the lower substrate (2000).

[0060] In this embodiment, the dielectric resonator includes two parts, a first dielectric antenna unit (1020) and a second dielectric antenna unit (1021), and there is no gap between the first dielectric antenna unit (1020) and the second dielectric antenna unit (1021).

[0061] The MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics in this embodiment can be fabricated using standard PCB processes (including drilling, copper cladding, and etching, etc.) or other processes. For example, a plurality of air vias (1030) are fabricated by drilling on the upper substrate (1000), and the plurality of air vias (1030) are arranged along the contour of a closed figure. The part of the upper substrate (1000) surrounded by the plurality of air vias (1030) forms the dielectric resonator; and each metal via in the MIMO substrate integrated antenna system can also be fabricated by drilling and copper cladding processes, and components such as microstrip lines, openings, and rectangular metal patches can all be fabricated by copper cladding and etching processes.

[0062] In this embodiment, the top view of the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics is as follows Figure 4 shown. Among them Figure 4 part (a) shows the distribution and dimensions of each component when looking at the upper substrate (1000), and part (b) shows the distribution of the copper-clad layer, i.e., the top layer plane (1010), when looking at the upper substrate (1000).

[0063] Referring to Figure 4 part (b), an opening (1050) is provided in the part of the top layer plane (1010) corresponding to the projection of the dielectric resonator. Specifically, after the upper surface of the upper substrate (1000) is fully copper-clad, the copper material is etched away in the part corresponding to the projection of the dielectric resonator, so as to obtain the part without copper-clad, and the opening (1050) of the top layer plane (1010) is formed. Referring to Figure 1 and Figure 4 part (b), the first dielectric antenna unit (1020) and the second dielectric antenna unit (1021) are installed in the opening (1050) on the upper surface of the upper substrate (1000), that is, the parts where the first dielectric antenna unit (1020) and the second dielectric antenna unit (1021) are in contact with the upper surface of the upper substrate (1000) have no copper-clad.

[0064] In this embodiment, the first dielectric antenna unit (1020) and the second dielectric antenna unit (1021) are located at the central position of the upper surface of the upper substrate (1000), and they are actually connected and there is no gap between them. Specifically, referring to Figure 1 and Figure 4 , the first dielectric antenna unit (1020) and the second dielectric antenna unit (1021) are arranged in the y direction. Taking the center as the boundary, half of the dielectric resonator in the -y direction is the first dielectric antenna unit (1020), and half of the dielectric resonator in the +y direction is the second dielectric antenna unit (1021).

[0065] In this embodiment, referring to Figure 5 , the decoupling structure is provided on the upper substrate (1000). Specifically, the decoupling structure includes a rectangular metal patch (1100) and a pair of metal vias (1090), where the pair of metal vias (1090) is composed of two metal vias. Referring to Figure 1 , Figure 2 and Figure 5, a rectangular metal patch (1100) is disposed on the upper surface of the upper substrate (1000), and the projection of the interface between the rectangular metal patch (1100) and the first dielectric antenna unit (1020) and the second dielectric antenna unit (1021) on the upper surface of the upper substrate (1000) coincides; one end of one metal via of the metal via pair (1090) is electrically connected to one end of the rectangular metal patch (1100), and one end of the other metal via of the metal via pair (1090) is electrically connected to the other end of the rectangular metal patch (1100). The metal via pair (1090) penetrates through the upper substrate (1000), and the other end of the metal via pair (1090) is electrically connected to the reference ground plane (2010).

[0066] Referring to Figure 5 , in the decoupling structure, the centers of the two metal vias in the metal via pair (1090) are aligned in the y-axis direction, symmetric about the center in the x-axis direction, and the distance from the center in the x-axis direction is d 13 , the diameters of the two metal vias in the metal via pair (1090) are both d 12 . The rectangular metal patch (1100) is located in the plane of the top layer plane (1010), its center is aligned, and its length is l 1 , and the width is w 1 , and is connected to the two metal vias in the metal via pair (1090), that is, connected to the reference ground plane through the two metal vias. In this way, the decoupling structure, namely the rectangular metal patch (1100), the metal via pair (1090), and the reference ground plane (2010) together form a metal loop.

[0067] In this embodiment, referring to Figure 1 and Figure 4 , the upper substrate (1000) is provided with a plurality of air vias (1030) and a plurality of first metal vias (1040). Specifically, the position distribution of the first metal vias (1040) on the upper substrate (1000) is as shown in Figure 4 part (c), and the position distribution of the air vias (1030) on the upper substrate (1000) is as shown in Figure 4 part (d).

[0068] Referring to Figure 4 part (c) and part (d), each air via (1030) is arranged approximately rectangularly inside the edge of the opening (1050). Similarly, each first metal via (1040) is arranged approximately rectangularly outside the edge of the opening (1050).

[0069] In this embodiment, the sizes of the air vias (1030) are as shown in Figure 6 . Referring to Figure 6In each air through-hole (1030), the distance from the center to the two sides parallel to the x-axis is d 1 and the distance from the center to the two sides parallel to the y-axis is d 2 and the center-to-center distance between two adjacent air through-holes is d 3 and the diameter of each air through-hole is d 4 .

[0070] In this embodiment, the dimensions of each first metal via (1040) are as Figure 7 shown. Referring to Figure 7 in each first metal via (1040), the distance from the center to the two sides parallel to the x-axis is d 5 and the distance from the center to the two sides parallel to the y-axis is d 6 and the center-to-center distance between two adjacent first metal vias is d 7 and the diameter of each first metal via is d 8 .

[0071] Referring to Figure 4 、 Figure 6 and Figure 7 , a circle of air through-holes (1030) and a circle of first metal vias (1040) can separate the first dielectric antenna unit (1020) and the second dielectric antenna unit (1021) from the surrounding dielectric

[0072] In this embodiment, referring to Figure 8 , the dielectric resonator is further provided with a plurality of second metal vias (1080), and each second metal via (1080) is distributed at the corners of the first dielectric antenna unit (1020) and the corners of the second dielectric antenna unit (1021). Specifically, referring to Figure 8 , one metal via is provided at each corner of the two dielectric antenna units, so there are a total of eight second metal vias (1080). These eight second metal vias (1080) are symmetrically distributed. The distance from the center to the four second metal vias (1080) closer to the center in the y-axis direction is d 9 and the distance from the center to the four second metal vias (1080) farther from the center is d 10 and the distance from the center to the eight second metal vias (1080) in the x-axis direction is d 11 and the diameter of each second metal via (1080) is d 12 . Referring to Figure 4 , the eight second metal vias (1080) are connected to circular pads on the top layer plane (1010), and the diameter of the pads is 0.6 mm

[0073] In this embodiment, referring to Figure 3In part (a), multiple metal vias for mounting (1060) are provided at the corners of the upper substrate (1000), and multiple metal vias for grounding (1070) distributed in a grid pattern are provided around the upper substrate (1000). Among them, the diameter of the metal via for mounting (1060) is 2 mm, and the diameter of the metal via for grounding (1070) is 1 mm. The center-to-center distance between two adjacent metal vias for mounting (1060) and between two adjacent metal vias for grounding (1070) is 3.27 mm. The distances from the outermost metal vias for mounting (1060) and metal vias for grounding (1070) to the edge of the upper substrate (1000) are both 2 mm.

[0074] In this embodiment, the "air via" in the air via (1030) refers to a drilled hole without copper plating on the sidewall in the PCB, and the "metal via" in the first metal via (1040), the second metal via (1080), the metal via for mounting (1060), the metal via for grounding (1070), and the metal via pair (1090) refers to a drilled hole with copper plating on the sidewall that connects the upper and lower layers of the PCB. The center refers to the reference origin on the horizontal plane (x - y plane).

[0075] Refer to Figure 3 , directly below each dielectric antenna unit, by etching away the copper plating on the reference ground plane (2010), the first slot (2020) and the second slot (2021) are left, where the first slot (2020) corresponds to the first dielectric antenna unit (1020), the second slot (2021) corresponds to the second dielectric antenna unit (1021), the first slot (2020) is located within the projection of the first dielectric antenna unit (1020), and the second slot (2021) is located within the projection of the second dielectric antenna unit (1021).

[0076] Refer to Figure 3 , the first slot (2020) is located at the center of the vertical projection of the first dielectric antenna unit (1020), and the second slot (2021) is located at the center of the vertical projection of the second dielectric antenna unit (1021). In this way, the first slot (2020) and the second slot (2021) are on the same straight line, and the first slot (2020) and the second slot (2021) are perpendicular to the projection of the rectangular metal patch (1100). The center-to-center distance between the first slot (2020) and the second slot (2021) is d 14 , the lengths of both the first slot (2020) and the second slot (2021) are l s , and the widths of both are w s .

[0077] In this embodiment, refer to Figure 1 , Figure 2 and Figure 3, on the lower surface of the lower substrate (2000), there are a first interface (2040), a second interface (2041), a first microstrip line (2030) and a second microstrip line (2031). One end of the first microstrip line (2030) is connected to the first interface (2040), and the second microstrip line (2031) is connected to the second interface (2041).

[0078] Referring to Figure 1 , Figure 2 and Figure 3 , the first microstrip line (2030) is parallel to the second microstrip line (2031). Referring to Figure 3 , the lengths of the first microstrip line and the second microstrip line (2031) are both l f , and the width is w f . The first microstrip line (2030) passes through the projection of the first dielectric antenna element (1020), and the first microstrip line (2030) intersects and is perpendicular to the projection of the first slot (2020). The distance from one end of the first microstrip line (2030) to the center of the first slot (2020) is d f , and the other end extends to a position beyond the first slot (2020) and then stops; the second microstrip line (2031) passes through the projection of the second dielectric antenna element (1021), and the second microstrip line (2031) intersects and is perpendicular to the projection of the second slot (2021). The distance from one end of the second microstrip line (2031) to the center of the second slot (2021) is also d f , and the other end extends to a position beyond the second slot (2021) and then stops.

[0079] In this embodiment, Figure 1 the working principle of the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics shown is as follows: The first interface (2040), the first microstrip line (2030) and the first slot (2020) can feed the first dielectric antenna element (1020). Therefore, the whole formed by the first interface (2040), the first microstrip line (2030), the first slot (2020) and the first dielectric antenna element (1020) forms an antenna in the MIMO antenna system; similarly, the whole formed by the second interface (2041), the second microstrip line (2031), the second slot (2021) and the second dielectric antenna element (1021) forms another antenna in the MIMO antenna system. Thus, the MIMO antenna system is realized; Assuming that the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics is not equipped with a decoupling structure, then when the first dielectric antenna element (1020) is excited through the first slot (2020) and the second dielectric antenna element (1021) uses a 50-ohm resistor for matching, the magnetic field distribution (indicated by arrows) of the MIMO substrate integrated antenna system is as Figure 9as shown in part (a) of the figure (this figure only shows the antenna part inside the substrate, and simplifies a circle of air vias into the vertical sidewalls of the antenna); and since a decoupling structure is actually equipped in the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics, the decoupling structure will also be excited, thereby introducing a magnetic field distribution. The magnetic field distribution introduced by the decoupling structure (indicated by arrows) is as shown in Figure 9 part (b) of; referring to Figure 9 part (a) of, assuming that the decoupling structure is not configured (uncoupled), there are mainly high-order modes in the dielectric resonator composed of the first dielectric antenna unit (1020) and the second dielectric antenna unit (1021) which significantly enhances the coupling energy in the second dielectric antenna unit (1021). The magnetic field direction in the second dielectric antenna unit (1021) is opposite to the magnetic field direction in the first dielectric antenna unit (1020), showing that the antenna radiation pattern of the first dielectric antenna unit (1020) is deformed; referring to Figure 9 part (b) of, in the configuration with a decoupling structure, while the first dielectric antenna unit (1020) is excited through the first slot (2020), the decoupling structure is also excited. Since the decoupling structure and the reference ground plane (2010) together form a loop [specifically, the metal via pair (1090), the rectangular metal patch (1100) and the reference ground plane (2010) form a closed metal loop], there will be a co-directional current loop in the loop. This co-directional current loop can be equivalent to a magnetic dipole. The direction of the magnetic field generated by it in the first dielectric antenna unit (1020) and the second dielectric antenna unit (1021) is the same as Figure 9 the magnetic field direction in the first dielectric antenna unit (1020) shown in part (a) of [for example, as shown in Figure 9 part (c) of, the left side is a schematic diagram of the simulated surface current distribution in the normal operating mode of the decoupling structure, with arrows indicating the current distribution. Using the relatively large size of the reference ground plane (2010), according to the mirror principle, the current can be approximately equivalent to the combination of the current on the rectangular metal patch (1100) and the metal via pair (1090) and its mirror image on the other side of the reference ground plane (2010). The right side is a schematic diagram of the equivalent current and the magnetic field distribution corresponding to this current. It can be seen that the normal operating mode of this decoupling structure can be approximately equivalent to a complete and continuous current loop. The magnetic field corresponding to this current loop can be approximately a magnetic dipole. The direction of this magnetic dipole is perpendicular to the current loop and is the same as the magnetic field direction in the first dielectric antenna unit (1020)], and according to the superposition principle, Figure 9 the magnetic field distribution shown in part (a) of assuming that there is no decoupling structure, and the magnetic field distribution caused by the decoupling structure itself shown in part (b) are superimposed to obtain Figure 9The magnetic field distribution shown in part (c): Inside the first dielectric antenna element (1020), the two are superimposed in the same direction; inside the second dielectric antenna element (1021), the two cancel each other out in the opposite direction. This superimposition effect enables the first dielectric antenna element (1020) to operate in its fundamental mode Its antenna radiation pattern remains symmetric and unchanged; the coupled energy inside the second dielectric antenna element (1021) is greatly reduced, improving port isolation; the electromagnetic field intensity inside the second dielectric antenna element (1021) is at a very low level relative to the first dielectric antenna element (1020), having no effect on the radiation pattern of the first dielectric antenna element (1020); at the same time, since the direction of the equivalent magnetic dipole introduced by the decoupling structure is the same as the magnetic field direction inside the first dielectric antenna element (1020), no additional cross-polarization components are introduced, keeping the cross-polarization of the radiation pattern at a low level.

[0080] In summary, the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics in this embodiment realizes decoupling between dielectric antenna elements through a decoupling structure with an improved technical route three, and does not introduce additional cross-polarization components, keeping the cross-polarization of the radiation pattern at a low level, achieving pattern conformal and cross-polarization suppression; a part of the decoupling structure is located inside the upper substrate (1000), and a part is flush with the upper surface of the upper substrate (1000). Such a structure can reduce the space occupied by the decoupling structure, making the overall space occupied by the MIMO substrate integrated antenna system small, which is beneficial to the miniaturization of the MIMO substrate integrated antenna system.

[0081] The MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics in this embodiment can reduce the occupied area of the MIMO antenna and improve its integration. Implementing a dielectric resonator antenna on a PCB substrate can achieve the following characteristics:

[0082] 1. Improve antenna port isolation;

[0083] 2. Protect the radiation pattern of the antenna element from being deformed and deteriorated by coupling;

[0084] 3. Do not introduce additional cross-polarization. Compared with the prior art, the antenna cross-polarization is reduced.

[0085] In this embodiment, the following dimensional values are set: l g = 30 mm, w g = 30 mm, t 1 = 1.27 mm, t 2 = 0.203 mm, d 1 = 4.6 mm, d 2 = 2.3 mm, d 3 = 1.3 mm, d4 = 1 mm, d 5 = 5.65 mm, d 6 = 3.35 mm, d 7 = 0.9 mm, d 8 = 0.6 mm, d 9 = 1 mm, d 10 = 3.6 mm, d 11 = 1.375 mm, d 12 = 0.3 mm, d 13 = 0.9 mm, l 1 = 2.4 mm, w 1 = 0.6 mm, d 14 = 4.6 mm, l s = 3 mm, w s = 0.3 mm, l f = 6.8 mm, w f = 0.4 mm, d f = 4.4 mm. The MIMO substrate integrated antenna system is set with these dimensional values for actual measurement and simulation.

[0086] The designed target frequency band in this embodiment is the 24 GHz ISM frequency band (24 - 24.25 GHz). Figure 10 , Figure 11 , Figure 12 Schematic diagrams of the actual measurement results and simulation results after the first interface (2040) and the second interface (2041) are connected to test equipment for testing.

[0087] Figure 10 Schematic diagrams of the scattering parameters of the actual measurement and simulation. The 10 dB impedance bandwidths of the actual measurement and simulation are 5.4% (23.7 - 25 GHz) and 5.0% (23.55 - 24.75 GHz) respectively. The small inconsistencies between the actual measurement and simulation results may be introduced by errors in processing and assembly. Within the 10 dB impedance bandwidth of the antenna, |S 21 | is maintained below -20 dB. Within the target frequency band, |S 21 | is reduced from approximately -6 dB in the un-decoupled configuration to approximately -26 dB, and the antenna isolation is improved by approximately 20 dB.

[0088] Figure 11 Schematic diagrams of the measured and simulated antenna radiation patterns at 24.125 GHz. The maximum radiation direction of the measured antenna radiation pattern is towards the z-axis, and the pattern remains symmetric. In the E-plane and H-plane, the cross-polarization is approximately 22 dB lower than the maximum gain of the co-polarization within the range of plus and minus 90°.

[0089] Figure 12 Schematic diagrams of the measured and simulated antenna gains. The measured antenna gain is approximately 5.5 dBi within the target frequency band.

[0090] Figure 13 It is a schematic diagram of the antenna envelope correlation coefficient under the non-decoupling configuration and the decoupling configuration of this embodiment in antenna simulation. Within the target frequency band, the antenna envelope correlation coefficient is lower than 0.01 after decoupling, showing a significant decrease compared to the non-decoupling configuration.

[0091] The measured results all conform to the predictions of the simulation. The measured and simulation results show that the MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics implemented in this embodiment achieves port decoupling, and realizes the design goals of maintaining the shape of the antenna radiation pattern and low cross-polarization. The antenna matching bandwidth and gain meet the expectations.

[0092] It should be noted that, unless otherwise specified, when a certain feature is referred to as "fixed" or "connected" to another feature, it can be directly fixed or connected to the other feature, or indirectly fixed or connected to the other feature. In addition, the descriptions such as up, down, left, and right used in this disclosure are only relative to the mutual positional relationship of the components of this disclosure in the drawings. The singular forms "a" and "the" used in this disclosure are also intended to include the plural forms, unless the context clearly indicates otherwise. In addition, unless otherwise defined, all the technical and scientific terms used in this embodiment have the same meanings as those commonly understood by those skilled in the technical field of this application. The terms used in the description of this embodiment are only for describing specific embodiments, rather than for limiting the present invention. The term "and / or" used in this embodiment includes any arbitrary combination of one or more of the related listed items.

[0093] It should be understood that although the terms first, second, third, etc. may be used in this disclosure to describe various elements, these elements should not be limited to these terms. These terms are only used to distinguish elements of the same type from each other. For example, without departing from the scope of this disclosure, the first element may also be referred to as the second element, and similarly, the second element may also be referred to as the first element. The use of any and all examples or exemplary languages ("for example", "such as", etc.) provided in this embodiment is only intended to better illustrate the embodiments of the present invention, and will not impose limitations on the scope of the present invention unless otherwise required.

[0094] It should be recognized that embodiments of the present invention can be implemented or carried out by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer-readable memory. The methods can be implemented in a computer program using standard programming techniques - including a non-transitory computer-readable storage medium configured with a computer program, wherein the storage medium so configured causes the computer to operate in a specific and predefined manner - in accordance with the methods and drawings described in the specific embodiments. Each program can be implemented in a high-level procedural or object-oriented programming language to communicate with the computer system. However, if desired, the program can be implemented in assembly or machine language. In any case, the language can be a compiled or interpreted language. In addition, for this purpose the program is capable of running on a programmed application-specific integrated circuit.

[0095] In addition, the operations of the processes described in this embodiment can be performed in any suitable order, unless this embodiment otherwise indicates or is clearly inconsistent with the context in other detected object forms. The processes described in this embodiment (or variations and / or combinations thereof) can be executed under the control of one or more computer systems configured with executable instructions, and can be implemented as code (e.g., executable instructions, one or more computer programs, or one or more applications) executed commonly on one or more processors, by hardware, or a combination thereof. The computer program includes a plurality of instructions executable by one or more processors.

[0096] Furthermore, the method can be implemented in any type of computing platform operably connected, including but not limited to personal computers, minicomputers, mainframes, workstations, network or distributed computing environments, separate or integrated computer platforms, or communicating with charged particle tools or other imaging devices, etc. Aspects of the present invention can be implemented in machine-readable code stored on a non-transitory storage medium or device, whether removable or integrated into the computing platform, such as a hard disk, optical read and / or write storage medium, RAM, ROM, etc., such that it can be read by a programmable computer and, when the storage medium or device is read by the computer, can be used to configure and operate the computer to execute the processes described herein. In addition, the machine-readable code, or portions thereof, can be transmitted via a wired or wireless network. When such media include instructions or programs that implement the above steps in combination with a microprocessor or other data processor, the invention of this embodiment includes these and other different types of non-transitory computer-readable storage media. When programmed according to the methods and techniques of the present invention, the present invention also includes the computer itself.

[0097] A computer program can be applied to input data to perform the functions of this embodiment, thereby converting the input data to generate output data stored in a non-volatile memory. The output information can also be applied to one or more output devices such as a display. In a preferred embodiment of the present invention, the converted data represents physical and tangible objects, including a specific visual depiction of the physical and tangible objects generated on the display.

[0098] The above is only a preferred embodiment of the present invention. The present invention is not limited to the above embodiments. As long as it achieves the technical effects of the present invention by the same means, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention. Within the scope of protection of the present invention, its technical solutions and / or implementation manners can have various different modifications and changes.

Claims

1. A MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics, characterized in that: The MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics comprises: An upper substrate (1000); the upper surface of the upper substrate (1000) is provided with a top plane (1010); A lower substrate (2000); a reference ground plane (2010) is provided on the upper surface of the lower substrate (2000), and the upper surface of the lower substrate (2000) is relatively bonded to the lower surface of the upper substrate (1000); A dielectric resonator; the dielectric resonator is arranged in the substrate dielectric of the upper substrate (1000); Decoupling structure; the decoupling structure is arranged on the upper substrate (1000), and the decoupling structure and the reference ground plane (2010) together form a loop.

2. The MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics according to claim 1, characterized in that: The top layer plane (1010) and the reference ground plane (2010) are both copper-clad layers.

3. The MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics according to claim 1, characterized in that: The dielectric resonator comprises a first dielectric antenna unit (1020) and a second dielectric antenna unit (1021), and the first dielectric antenna unit (1020) and the second dielectric antenna unit (1021) are joined without a gap.

4. The MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics according to claim 3, characterized in that: The decoupling structure comprises a rectangular metal patch (1100) and a pair of metal vias (1090); The rectangular metal patch (1100) is arranged on the upper surface of the upper substrate (1000), and the rectangular metal patch (1100) overlaps with the projection of the interface between the first dielectric antenna unit (1020) and the second dielectric antenna unit (1021); One end of the metal via pair (1090) is electrically connected to two ends of the rectangular metal patch (1100), the metal via pair (1090) passes through the upper substrate (1000), and the other end of the metal via pair (1090) is electrically connected to the reference ground plane (2010).

5. The MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics according to claim 1, characterized in that: An opening (1050) is provided on a portion of the top plane (1010) corresponding to the projection of the dielectric resonator; The upper substrate (1000) is provided with a plurality of air through holes (1030) and a plurality of first metal via holes (1040); The air through holes (1030) are arranged along the inner edge of the opening (1050); Each of the first metal vias (1040) is arranged along the outer edge of the opening (1050).

6. The MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics according to claim 3, characterized in that: The dielectric resonator is provided with a plurality of second metal vias (1080); Each of the second metal vias (1080) is distributed at a corner of the first dielectric antenna unit (1020) and a corner of the second dielectric antenna unit (1021); The corners of the upper substrate (1000) are provided with a plurality of metal vias (1060) for installation; A plurality of grounding metal vias (1070) distributed in a grid pattern are arranged around the upper substrate (1000).

7. The MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics according to claim 4, characterized in that: The reference ground plane (2010) is provided with a first gap (2020) and a second gap (2021); The first slit (2020) is located at the center of the vertical projection of the first dielectric antenna unit (1020), and the second slit (2021) is located at the center of the vertical projection of the second dielectric antenna unit (1021).

8. The MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics according to claim 7, characterized in that: The first slit (2020) and the second slit (2021) are perpendicular to the projection of the rectangular metal patch (1100).

9. The MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics according to claim 7 or 8, characterized in that: The MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression features also includes: A first interface (2040) and a second interface (2041); the first interface (2040) and the second interface (2041) are installed on the lower surface of the lower substrate (2000); A first microstrip line (2030) and a second microstrip line (2031); the first microstrip line (2030) and the second microstrip line (2031) are arranged on the lower surface of the lower substrate (2000); one end of the first microstrip line (2030) is connected to the first interface (2040), and the second microstrip line (2031) is connected to the second interface (2041); the first microstrip line (2030) passes through the projection of the first dielectric antenna unit (1020), and the second microstrip line (2031) passes through the projection of the second dielectric antenna unit (1021); the first microstrip line (2030) and the second microstrip line (2031) are parallel.

10. The MIMO substrate integrated antenna system with pattern conformal and cross-polarization suppression characteristics according to claim 9, characterized in that: The first microstrip line (2030) intersects and is perpendicular to a projection of the first slot (2020); The second microstrip line (2031) intersects and is perpendicular to the projection of the second slot (2021).

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