Broadband GNSS antenna

Abstract

This application provides a broadband GNSS antenna, which includes a PCB reflector, a dielectric layer, and multiple network antennas. The dielectric layer is disposed on the PCB reflector, with an air gap forming between the dielectric layer and the PCB reflector. A radiating element and multiple first patches are disposed on the dielectric layer. The radiating element includes a ring-shaped radiating patch and multiple rectangular stubs. The rectangular stubs are located on the inner periphery of the ring-shaped radiating patch and arranged at equal angles along the center of the dielectric layer. The first patches and rectangular stubs are spaced apart, and each first patch has a first feed hole. The multiple network antennas are arranged at equal angles along the center of the dielectric layer. By loading multiple rectangular stubs onto the ring-shaped radiating patch, a dual-band GNSS antenna is achieved. Capacitive coupling feeding via the first patches broadens the bandwidth of the GNSS antenna. Furthermore, the combination of the dielectric layer and the air gap reduces the weight of the GNSS antenna.

Description

Technical Field

[0001] This application relates to the field of antenna technology, and in particular to a broadband GNSS antenna. Background Technology

[0002] With the development of GNSS antenna technology, the requirements for the navigation, positioning and measurement capabilities of GNSS antennas are becoming increasingly higher. Therefore, GNSS antennas are required to have characteristics such as ultra-wideband gain bandwidth, light weight and small size.

[0003] However, in related technologies, GNSS antennas typically adopt a structure design with dielectric layers stacked. Although this can meet the gain and bandwidth requirements, the GNSS antenna is heavy and large in size, and cannot meet the requirements of broadband design while also being lightweight. Summary of the Invention

[0004] This application discloses a broadband GNSS antenna that can meet the requirements of broadband design for GNSS antennas while also taking into account the design requirements of lightweight design.

[0005] To achieve the above objectives, this application discloses a broadband GNSS antenna, which includes:

[0006] PCB reflector;

[0007] A dielectric layer is disposed on the PCB reflector, and an air gap is formed between the dielectric layer and the PCB reflector. The dielectric layer is provided with a radiating unit and a plurality of first patches. The radiating unit includes an annular radiating patch and a plurality of rectangular branches. The center of the annular radiating patch coincides with the center of the dielectric layer. The plurality of rectangular branches are disposed on the inner periphery of the annular radiating patch and are arranged at equal angles along the center of the dielectric layer. The plurality of rectangular branches extend from the inner periphery edge of the annular radiating patch toward the center of the dielectric layer.

[0008] A plurality of first patches are located on the inner periphery of the annular radiating patch. The plurality of first patches are arranged at equal angles along the center of the dielectric layer and spaced apart from the rectangular branches. Each first patch is also provided with a first feed hole, which penetrates the dielectric layer to achieve coupling between the first patch and the annular radiating patch; and

[0009] Multiple network antennas are disposed at equal angles along the center of the dielectric layer on the dielectric layer.

[0010] As an optional implementation, the number of the first patch is the same as the number of the rectangular branches, and both the number of the first patch and the number of the rectangular branches are even.

[0011] As an optional implementation, the first patch includes an arc-shaped portion and a rectangular portion connected to the arc-shaped portion, the arc-shaped portion being located between adjacent rectangular branches, the rectangular portion extending from the arc-shaped portion toward the center of the dielectric layer, and the first feed hole being disposed in the arc-shaped portion.

[0012] As an optional implementation, the dielectric layer includes a first layer and a second layer, wherein the first layer is spaced apart from the PCB reflector to form the air gap, and the side of the first layer facing away from the PCB reflector is the first side, and the radiating unit and a plurality of first patches are disposed on the first side;

[0013] The second layer is located on the outer periphery of the first layer. The second layer is spaced apart from the PCB reflector, and the distance from the second layer to the PCB reflector is less than the distance from the first layer to the PCB reflector. The second layer includes a second side and a third side arranged opposite to each other, and the third side is the side facing away from the PCB reflector.

[0014] The second and third surfaces are provided with a plurality of network antennas.

[0015] As an optional implementation, the first surface is further provided with a plurality of tuning units. Each tuning unit includes a second patch and a first metal hole disposed on the second patch. The plurality of second patches are arranged at equal angles along the center of the first surface. The plurality of second patches are located on the outer periphery of the annular radiating patch and are disposed near the edge of the first surface.

[0016] The first metal hole extends through the first layer to form a short-circuit hole, and the first metal hole is also used to connect fasteners so that the first layer is fixedly connected to the PCB reflector.

[0017] As an optional implementation, the dielectric layer is cylindrical, and the second patch includes a first extension, a second extension, and a folded portion. The first extension and the second extension are respectively connected to both ends of the folded portion. The first extension and the second extension extend circumferentially along the first surface, and the folded portion extends radially along the first surface. The first metal hole is disposed in the first extension or the second extension.

[0018] As an optional implementation, the thickness of the first layer is 1.5mm-2.5mm, the thickness of the second layer is 1mm-1.5mm, the distance from the first layer to the PCB reflector is 8mm-12mm, the distance from the second layer to the PCB reflector is 7mm-9mm, and / or,

[0019] The dielectric constant of the first layer is 2.2-6.15, and the dielectric constant of the second layer is 4.2-4.7.

[0020] As an optional implementation, the GNSS antenna further includes multiple microstrip lines, each microstrip line being configured corresponding to a network antenna. One end of each microstrip line is connected to the network antenna, and the other end of each microstrip line is connected to the PCB reflector, so as to feed the network antenna and fix the dielectric layer to the PCB reflector.

[0021] As an optional implementation, the GNSS antenna further includes a radio antenna, wherein a through hole is provided in the center of the dielectric layer, and the radio antenna passes through the through hole and is connected to the PCB reflector.

[0022] As an optional implementation, the network antenna includes a 4G main antenna, a 4G diversity antenna, a Bluetooth / WiFi main antenna, and a Bluetooth / WiFi diversity antenna. The 4G main antenna and the 4G diversity antenna are symmetrically distributed with the center of the dielectric layer as the center, and the Bluetooth / WiFi main antenna and the Bluetooth / WiFi diversity antenna are symmetrically distributed with the center of the dielectric layer as the center.

[0023] The 4G main antenna includes a first stub, a second stub, a third stub, and a semi-circular arc stub. The three stubs are provided with a second metal hole, which is used to connect the third stub and the semi-circular arc stub.

[0024] Compared with the prior art, the beneficial effects of this application are as follows:

[0025] The broadband GNSS antenna provided in this application includes a PCB reflector, a dielectric layer, and a network antenna. By placing the dielectric layer on the PCB reflector and forming an air gap between the dielectric layer and the PCB reflector, and by providing radiating elements and multiple first patches on the dielectric layer, the radiating elements include a ring-shaped radiating patch and multiple rectangular stubs. In this way, by loading multiple rectangular stubs onto the ring-shaped radiating patch, a dual-band operating frequency for the GNSS antenna is achieved. Combined with the capacitive coupling feeding method implemented by the multiple first patches, the bandwidth of the GNSS antenna can be widened. Simultaneously, the combination of the dielectric layer and the air gap reduces the Q value of the GNSS antenna, further improving its bandwidth performance and reducing its weight. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a three-dimensional structural schematic diagram of the GNSS antenna disclosed in this application;

[0028] Figure 2 This is a front view of the GNSS antenna along the first surface according to an embodiment of this application;

[0029] Figure 3 This is a side view of a GNSS antenna according to an embodiment of this application;

[0030] Figure 4 This is a schematic diagram of the structure of the second patch according to an embodiment of this application;

[0031] Figure 5 This is a schematic diagram of the structure of a GNSS antenna equipped with a radio antenna according to an embodiment of this application;

[0032] Figure 6 This is a schematic diagram of the structure of the 4G main antenna according to an embodiment of this application;

[0033] Figure 7 This is the passive gain curve of the GNSS antenna in an embodiment of this application;

[0034] Figure 8 This is a comparison graph of the axial ratio curves of the GNSS antenna with and without a tuning unit in the 1.225GHz band according to an embodiment of this application;

[0035] Figure 9 This is a comparison graph of the axial ratio curves of the GNSS antenna with and without a tuning unit in the 1.575GHz band according to an embodiment of this application.

[0036] Icons: 10, PCB reflector; 20, dielectric layer; 21, first layer; 21a, first surface; 211, radiating unit; 211a, annular radiating patch; 211b, rectangular branch; 212, first patch; 212a, arc-shaped portion; 212b, rectangular portion; 213, first feed hole; 214, tuning unit; 2141, second patch; 2141a, first extension; 2141b, second extension; 2141c, folded portion; 2142, first metal hole ; 22, Second layer; 22a, Second surface; 22b, Third surface; 23, Through hole; 30, Network antenna; 31, 4G main antenna; 311, First stub; 312, Second stub; 313, Third stub; 313a, Second metal hole; 314, Semi-circular arc stub; 32, 4G diversity antenna; 33, Bluetooth / WiFi main antenna; 34, Bluetooth / WiFi diversity antenna; 35, Second feed hole; 40, Air gap; 50, Microstrip line; 60, Radio antenna. Detailed Implementation

[0037] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0038] In this application, the term "above" indicates the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0039] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0040] Furthermore, the terms "set up," "equipped with," and "connected" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0041] Furthermore, the terms "first," "second," "third," etc., are primarily used to distinguish different devices, components, or parts (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, components, or parts. Unless otherwise stated, "a plurality of" means two or more.

[0042] The technical solution of this application will be further described below with reference to the embodiments and accompanying drawings.

[0043] Please refer to the following: Figures 1 to 4 This application provides a broadband GNSS antenna, which includes a PCB reflector 10, a dielectric layer 20, and multiple network antennas 30. The dielectric layer 20 is disposed on the PCB reflector 10, and an air gap 40 is formed between the dielectric layer 20 and the PCB reflector 10. The dielectric layer 20 is provided with radiating elements 211 and multiple first patches 212. The radiating element 211 includes an annular radiating patch 211a and multiple rectangular branches 211b. The center of the annular radiating patch 211a coincides with the center of the dielectric layer 20. The multiple rectangular branches 211b are disposed on the inner periphery of the annular radiating patch 211a and are arranged at equal angles along the center of the dielectric layer 20. The multiple rectangular branches 211b extend from the inner periphery edge of the annular radiating patch 211a towards the center of the dielectric layer 20. Multiple first patches 212 are located on the inner periphery of the annular radiating patch 211a. These first patches 212 are arranged at equal angles along the center of the dielectric layer 20 and spaced apart from the rectangular stubs 211b. Each first patch 212 also has a first feed hole 213 that penetrates the dielectric layer 20 to achieve coupling between the first patch 212 and the annular radiating patch 211a. Multiple network antennas 30 are arranged at equal angles along the center of the dielectric layer 20.

[0044] It should be noted that the air gap 40 mentioned above refers to the space between the dielectric layer 20 and the PCB reflector 10, which is set apart.

[0045] Optionally, the dielectric layer 20 is cylindrical, and the annular radial patch 211a is an annular patch. Of course, in some other embodiments, the annular radial patch 211a can also be a polygonal annular patch, such as a quadrilateral, pentagon, or hexagon.

[0046] In this embodiment, a dielectric layer 20 is disposed on a PCB reflector 10, forming an air gap 40 between the dielectric layer 20 and the PCB reflector 10. A radiating element 211 and multiple first patches 212 are provided on the dielectric layer 20. The radiating element 211 includes an annular radiating patch 211a and multiple rectangular stubs 211b. Thus, the GNSS antenna achieves low-frequency gain using capacitively coupled feeding. Furthermore, the rectangular stubs 211b, disposed on the inner periphery of the annular radiating patch 211a and extending towards the center of the dielectric layer 20, effectively extend the current path in the high-frequency band, further enhancing the capacitive coupling between the annular radiating patch 211a and the first patches 212, thereby improving the high-frequency gain and enabling the GNSS antenna to achieve dual-frequency operation. In this way, the design that can cover the dual-frequency operating band with only a single ring radiating patch 211a makes the structure of the GNSS antenna simpler and easier to debug. At the same time, the combination of capacitive coupling feeding method implemented by multiple first patches 212 can also broaden the bandwidth of the GNSS antenna.

[0047] In this embodiment, the GNSS antenna has a gain of 3.5 dBi or higher in the operating frequency range of 1.136 GHz to 1.87 GHz, and an antenna gain of 3.9 dBi or higher in the operating frequency range of 1.165 GHz to 1.620 GHz.

[0048] Furthermore, the combination of dielectric layer 20 and air gap 40 reduces the Q value of the GNSS antenna, further improving its bandwidth performance while also reducing its weight. It is understood that the Q value of an antenna is equivalent to its quality factor; a higher Q value corresponds to a narrower bandwidth. Therefore, widening the bandwidth can reduce the Q value. For example, increasing the thickness of dielectric layer 20 or selecting a dielectric layer 20 with a low dielectric constant can both lower the Q value.

[0049] In some embodiments, the number of first patches 212 is the same as the number of rectangular stubs 211b, and both the number of first patches 212 and rectangular stubs 211b are even. Preferably, the number of first patches 212 and rectangular stubs 211b are both four, then the number of first feed holes 213 corresponding to the first patches 212 is also four, and the phase difference between two adjacent first feed holes 213 is 90°, which is beneficial to achieving the circular polarization performance of the GNSS antenna. Furthermore, the four-feed method with capacitive coupling reduces the number of feeds, lowers the processing complexity and design cost of the GNSS antenna, simplifies the feed network, and facilitates the layout of the active circuit in subsequent miniaturized designs. On the other hand, it also compensates for the parasitic input inductance generated by the excessively long feed probes introduced to achieve ultra-wideband characteristics, further optimizing the ultra-wideband impedance matching of the GNSS antenna. Of course, in some other embodiments, the number of first patches 212 and rectangular stubs 211b can also be two, six, eight, etc.

[0050] See Figure 2 Optionally, the first patch can be approximately a T-shaped patch. For example, the first patch 212 includes an arcuate portion 212a and a rectangular portion 212b connected to the arcuate portion 212a. The arcuate portion 212a is located between adjacent rectangular stubs 211b, and the rectangular portion 212b extends from the arcuate portion 212a towards the center of the dielectric layer 20. A first feed hole 213 is disposed in the arcuate portion 212a. By adopting the design of the first patch 212 including the arcuate portion 212a and the rectangular portion 212b connected to the arcuate portion 212a, the shape of the arcuate portion 212a can be adapted to the fan-shaped space formed by two adjacent rectangular stubs 211b. This facilitates the utilization of the space within the annular radiating patch 211a, enhances the coupling strength between the annular radiating patch 211a and the first patch, and thus helps to improve the antenna gain in the high-frequency band.

[0051] See Figure 1 and Figure 3 In some embodiments, the dielectric layer 20 includes a first layer 21 and a second layer 22. The first layer 21 is spaced apart from the PCB reflector 10 to form an air gap 40. The side of the first layer 21 facing away from the PCB reflector 10 is the first side 21a (i.e., as shown in the image). Figure 3 (As shown, the upward-facing side), radiating units 211 and multiple first patches 212 are disposed on the first surface 21a; the second layer 22 is located on the outer periphery of the first layer 21, the second layer 22 is spaced apart from the PCB reflector 10, and the distance between the second layer 22 and the PCB reflector 10 is less than the distance between the first layer 21 and the PCB reflector 10. The second layer 22 includes a second surface 22a disposed opposite to it (i.e., as shown on the upward-facing side). Figure 3 The downward-facing side shown) and the third side 22b (i.e., as shown) Figure 3As shown (the upward-facing side), the third side 22b is the side facing away from the PCB reflector 10. Multiple network antennas 30 are provided on the second side 22a and the third side 22b. It is understood that the dielectric layer 20 is designed to include a first layer 21 and a second layer 22, such that the distance from the second layer 22 to the PCB reflector 10 is less than the distance from the first layer 21 to the PCB reflector 10, that is, along... Figure 3 In the vertical direction H, there is a height difference between the first layer 21 and the second layer 22. This is beneficial for the design of the network antenna 30, as the height difference can be used to improve the isolation between the antennas and reduce interference between them, thereby meeting the performance requirements of the GNSS antenna. At the same time, using an air gap 40 as an air dielectric layer can reduce the weight of the GNSS antenna, which also helps to achieve the lightweight design of the GNSS antenna.

[0052] In some embodiments, to broaden the axial ratio bandwidth of the GNSS antenna, thereby improving the polarization purity at low elevation angles and enhancing multipath suppression capabilities, a plurality of tuning units 214 are also provided on the first surface 21a. Each tuning unit 214 includes a second patch 2141 and a first metal hole 2142 disposed on the second patch 2141. The plurality of second patches 2141 are arranged at equal angles along the center of the first surface 21a, located on the outer periphery of the annular radiating patch 211a, and near the edge of the first surface 21a. The first metal hole 2142 extends through to the first layer 21 to form a short-circuit hole. The first metal hole 2142 is also used to connect fasteners to fix the first layer 21 to the PCB reflector 10. It is understood that the fasteners may include, but are not limited to, screws, bolts, etc. By using the second patch 2141 and the first metal hole 2142 as the tuning unit 214, the 3dB axial ratio bandwidth of traditional stacked and single-layer antennas, which are both about ±70° in the high and low frequency bands, can be broadened to about ±114° in the high frequency band and about ±100° in the low frequency band. At the same time, the miniaturization design of GNSS antennas can be further realized.

[0053] For example, the number of first metal holes 2142 can be 8, then the number of corresponding second patches 2141 is also 8. It is understood that the number of first metal holes 2142 can also be 6, 10 or other numbers, which can be determined according to the setting space of the first surface 121 and to meet the stable operation of the GNSS antenna. This embodiment does not make a specific limitation in this regard.

[0054] See Figure 4Optionally, as described above, the dielectric layer 20 is cylindrical, and the second patch 2141 includes a first extension 2141a, a second extension 2141b, and a folded portion 2141c. The first extension 2141a and the second extension 2141b are respectively connected to the two ends of the folded portion 2141c. The first extension 2141a and the second extension 2141b extend circumferentially along the first surface 21a, and the folded portion 2141c extends radially along the first surface 21a. The first metal hole 2142 is disposed in the first extension 2141a or the second extension 2141b. For example, the first extension 2141a and the second extension 2141b are rectangular, and the folded portion 2141c is approximately a continuous columnar structure. Through the design of the first extension 2141a, the second extension 2141b and the folded portion 2141c, the size of the second patch 2141 can be effectively increased, which is beneficial to extending the current path, thereby causing the tuning resonant frequency to shift towards the lower frequency direction, and thus making the tuning resonance effect better.

[0055] It is understood that in some other embodiments, the second patch 2141 may also take other shapes, such as an arc patch, an elliptical patch, etc.

[0056] In some embodiments, if the distance between the dielectric layer 20 and the PCB reflector 10 is too small, it can easily lead to excessive coupling between the GNSS antenna and the network antenna 30, causing interference between the antennas. If the distance between the dielectric layer 20 and the PCB reflector 10 is too large, it will increase the overall size of the GNSS antenna, which is not conducive to miniaturization and lightweight design. Therefore, the thickness of the dielectric layer 20 and its distance to the PCB reflector are designed. Specifically, the thickness of the first layer 21 is 1.5mm-2.5mm, the thickness of the second layer 22 is 1mm-1.5mm, the distance between the first layer 21 and the PCB reflector 10 is 8mm-12mm, and the distance between the second layer 22 and the PCB reflector 10 is 7mm-9mm. Preferably, the thickness of the first layer 21 is 2mm, the thickness of the second layer 22 is 1.2mm, the distance between the first layer 21 and the PCB reflector 10 is 10mm, and the distance between the second layer 22 and the PCB reflector 10 is 8mm.

[0057] In some embodiments, the first layer 21 and the second layer 22 can be made of materials with high dielectric constants, i.e., the dielectric constant of the first layer 21 is 2.2-6.15, and the dielectric constant of the second layer 22 is 4.2-4.7. For example, the first layer 21 can be an F4B substrate, and the second layer 22 can be an FR4 substrate with a dielectric constant of 4.4. This GNSS antenna uses a combination of high dielectric constant materials and air as the dielectric medium. On the one hand, this increases the radiative conductivity of the GNSS antenna and decreases the Q value of the dielectric, thereby helping to extend the bandwidth of the GNSS antenna. On the other hand, it reduces the weight of the GNSS antenna, thereby reducing the design cost of the GNSS antenna.

[0058] In some embodiments, to feed the network antenna 30, the GNSS antenna further includes multiple microstrip lines 50, each microstrip line 50 corresponding to a specific network antenna 30. One end of each microstrip line 50 is connected to the network antenna 30, and the other end is connected to the PCB reflector 10, thereby feeding the network antenna 30 and fixing the dielectric layer 20 to the PCB reflector 10. See also Figure 3 and Figure 6 It is understandable that the microstrip line 50 is located between the second layer 22 and the PCB reflector 10. The network antenna 30 also has a second feed hole 35, which is positioned corresponding to the network antenna 30. One end of the microstrip line 50 is connected to the network antenna 30 through the second feed hole 35 to feed the network antenna 30, while the other end of the microstrip line 50 is connected to the PCB reflector 10, thereby effectively fixing the second layer 22, which is beneficial to the reliability and robustness of the GNSS antenna. The design of the microstrip line 50 serves two purposes: feeding the network antenna 30 and supporting the second layer 22. This eliminates the need for additional fixing holes, saving space in the second layer 22, which is beneficial for the layout of the network antenna 30, and also simplifies the manufacturing process, thus reducing manufacturing costs.

[0059] Furthermore, the microstrip line 50 can be H-shaped, and grounding patches 51 are provided on both sides of the microstrip line 50 to achieve the grounding function of the microstrip line 50. It is understood that in some other embodiments, the microstrip line 50 can also adopt other shapes, such as L-shaped, T-shaped, etc. The specific shape can be selected according to the actual situation, and this embodiment does not make a specific limitation on it.

[0060] See Figure 5 In some embodiments, the GNSS antenna also includes a radio antenna 60. A through-hole 23 is provided in the center of the dielectric layer 20, and the radio antenna 60 passes through the through-hole 23 and is connected to the PCB reflector 10. By providing a through-hole 23 in the center of the dielectric layer 20, the radio antenna 60 can be further provided, so that the GNSS antenna can be compatible with more antennas, meeting the multi-system requirements and measurement requirements of high-precision GNSS receivers.

[0061] See Figure 5 and Figure 6 In some embodiments, the network antenna 30 includes a 4G main antenna 31, a 4G diversity antenna 32, a Bluetooth / WiFi main antenna 33, and a Bluetooth / WiFi diversity antenna 34. The 4G main antenna 31 and 4G diversity antenna 32 are symmetrically distributed around the center of the dielectric layer 20, and the Bluetooth / WiFi main antenna 33 and Bluetooth / WiFi diversity antenna 34 are also symmetrically distributed around the center of the dielectric layer 20. It is understood that the 4G main antenna 31 and 4G diversity antenna 32 have the same structural dimensions, and the Bluetooth / WiFi main antenna 33 and Bluetooth / WiFi diversity antenna 34 have the same structural dimensions. This helps reduce mutual interference between the network antennas 30, reduces the coupling between the antennas, and is beneficial to the stability of the GNSS antenna phase center. Exemplarily, the network antenna 30 can be a PIFA antenna. Of course, in some other embodiments, other types of antennas, such as IFA antennas, can also be used. The specific choice can be made according to actual needs, and this application does not impose any special limitations on this.

[0062] Optionally, the 4G main antenna 31 includes a first stub 311, a second stub 312, a third stub 313, and a semi-circular arc stub 314. The first stub 311, the second stub 312, and the third stub 313 are located on the third surface 22b, and the semi-circular arc stub 314 is located on the second surface 22a. The third stub 313 has a second metal hole 313a for connecting the third stub 313 and the semi-circular arc stub 314. It is understood that the lengths of the first stub 311, the second stub 312, the third stub 313, and the semi-circular arc stub 314 extend circumferentially along the second layer 22. Among them, the first branch 311 is the shortest branch, and the third branch 313 and the semi-circular arc branch constitute the longest branch. The third branch 313 includes two parts, which are connected by a semi-circular arc branch 314 disposed on the second surface 22a. Therefore, both ends of the semi-circular arc branch 314 are provided with metal holes corresponding to the second metal hole 313a. The above-mentioned branch arrangement is mainly used for tuning resonance to achieve high-speed communication.

[0063] Please see Figure 7 , Figure 7 This is the passive gain curve of the GNSS antenna according to an embodiment of this application. Figure 8 This is a comparison graph showing the axial ratio of the GNSS antenna in the 1.225GHz band with and without the tuning unit 214, according to an embodiment of this application. Figure 9 This is a comparison graph showing the axial ratio of the GNSS antenna in the 1.575GHz band with and without the tuning unit 214, according to an embodiment of this application. Figure 7 The horizontal axis represents frequency. Figure 7 The vertical axis represents the gain, from Figure 7 As can be seen, the GNSS antenna uses a single ring radiating patch 211a, achieving ultra-wideband performance. The operating frequency band with a gain of over 3.5dBi is 1.136-1.87GHz, while the gain in the 1.165GHz-1.620GHz band can reach over 3.9dBi. The gain is relatively flat throughout the entire frequency band, which can cover GPS navigation system, BDS navigation system, Galileo navigation system, GLONASS navigation system and L band.

[0064] Figure 8 , Figure 9 In the diagram, the horizontal axis represents the low elevation angle, and the vertical axis represents the axial ratio. Figure 8 , Figure 9 The solid line in the figure represents the axial ratio curve without the tuning unit 214 loaded. Figure 8 , Figure 9 The dashed line in the figure represents the axial ratio curve of the loaded tuning unit 214. From... Figure 8 , Figure 9 As can be seen, compared with the method without tuning unit 214, the GNSS antenna of this application with tuning unit 214 has a 3dB axial ratio bandwidth of approximately ±100° and ±114° in the high and low frequency bands, respectively, which has better wide-angle axial ratio characteristics and is beneficial to improving the polarization purity at low elevation angles and the ability to resist multipath suppression.

[0065] The broadband GNSS antenna disclosed in the embodiments of this application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the broadband GNSS antenna and its core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A broadband GNSS antenna, characterized in that, The GNSS antenna includes: PCB reflector; A dielectric layer is disposed on the PCB reflector, and an air gap is formed between the dielectric layer and the PCB reflector. The dielectric layer is provided with a radiating unit and a plurality of first patches. The radiating unit includes an annular radiating patch and a plurality of rectangular branches. The center of the annular radiating patch coincides with the center of the dielectric layer. The plurality of rectangular branches are disposed on the inner periphery of the annular radiating patch and are arranged at equal angles along the center of the dielectric layer. The plurality of rectangular branches extend from the inner periphery edge of the annular radiating patch toward the center of the dielectric layer. A plurality of first patches are located on the inner periphery of the annular radiating patch. The plurality of first patches are arranged at equal angles along the center of the dielectric layer and spaced apart from the rectangular branches. Each first patch is also provided with a first feed hole, which penetrates the dielectric layer to achieve coupling between the first patch and the annular radiating patch; and Multiple network antennas are disposed at equal angles along the center of the dielectric layer on the dielectric layer.

2. The broadband GNSS antenna according to claim 1, characterized in that, The number of the first patch is the same as the number of the rectangular branches, and both the number of the first patch and the number of the rectangular branches are even.

3. The broadband GNSS antenna according to claim 2, characterized in that, The first patch includes an arc-shaped portion and a rectangular portion connected to the arc-shaped portion. The arc-shaped portion is located between adjacent rectangular branches, and the rectangular portion extends from the arc-shaped portion toward the center of the dielectric layer. The first feed hole is disposed in the arc-shaped portion.

4. The broadband GNSS antenna according to claim 1, characterized in that, The dielectric layer includes a first layer and a second layer. The first layer is spaced apart from the PCB reflector to form the air gap. The side of the first layer facing away from the PCB reflector is the first side. The radiating unit and a plurality of first patches are disposed on the first side. The second layer is located on the outer periphery of the first layer. The second layer is spaced apart from the PCB reflector, and the distance from the second layer to the PCB reflector is less than the distance from the first layer to the PCB reflector. The second layer includes a second side and a third side arranged opposite to each other, and the third side is the side facing away from the PCB reflector. The second and third surfaces are provided with a plurality of network antennas.

5. The broadband GNSS antenna according to claim 4, characterized in that, The first surface is also provided with a plurality of tuning units. Each tuning unit includes a second patch and a first metal hole disposed on the second patch. The plurality of second patches are arranged at equal angles along the center of the first surface. The plurality of second patches are located on the outer periphery of the annular radiating patch and are disposed near the edge of the first surface. The first metal hole extends through the first layer to form a short-circuit hole, and the first metal hole is also used to connect fasteners so that the first layer is fixedly connected to the PCB reflector.

6. The broadband GNSS antenna according to claim 5, characterized in that, The dielectric layer is cylindrical, and the second patch includes a first extension, a second extension, and a folded portion. The first extension and the second extension are respectively connected to both ends of the folded portion. The first extension and the second extension extend circumferentially along the first surface, and the folded portion extends radially along the first surface. The first metal hole is disposed in the first extension or the second extension.

7. The broadband GNSS antenna according to any one of claims 4-6, characterized in that, The thickness of the first layer is 1.5mm-2.5mm, the thickness of the second layer is 1mm-1.5mm, the distance from the first layer to the PCB reflector is 8mm-12mm, the distance from the second layer to the PCB reflector is 7mm-9mm, and / or, The dielectric constant of the first layer is 2.2-6.15, and the dielectric constant of the second layer is 4.2-4.

7.

8. The broadband GNSS antenna according to any one of claims 1-7, characterized in that, The GNSS antenna also includes multiple microstrip lines, each microstrip line corresponding to a network antenna. One end of each microstrip line is connected to the network antenna, and the other end of each microstrip line is connected to the PCB reflector, so as to feed the network antenna and fix the dielectric layer to the PCB reflector.

9. The broadband GNSS antenna according to any one of claims 1-7, characterized in that, The GNSS antenna also includes a radio antenna. A through hole is provided in the center of the dielectric layer, and the radio antenna passes through the through hole and is connected to the PCB reflector.

10. The broadband GNSS antenna according to any one of claims 1-7, characterized in that, The network antenna includes a 4G main antenna, a 4G diversity antenna, a Bluetooth / WiFi main antenna, and a Bluetooth / WiFi diversity antenna. The 4G main antenna and the 4G diversity antenna are symmetrically distributed along the center of the dielectric layer, and the Bluetooth / WiFi main antenna and the Bluetooth / WiFi diversity antenna are symmetrically distributed along the center of the dielectric layer. The 4G main antenna includes a first stub, a second stub, a third stub, and a semi-circular arc stub. The third stub is provided with a second metal hole, which is used to connect the third stub and the semi-circular arc stub.

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