Double-frequency automobile glass antenna applied to vehicle-mounted satellite navigation

Abstract

The invention relates to the technical field of vehicle-mounted antennas, and aims to solve the technical problem of low antenna gain. In order to solve the technical problem, the invention provides the double-frequency automobile glass antenna applied to vehicle-mounted satellite navigation. According to the invention, an intermediate dielectric layer is stacked below an outer glass dielectric layer; the inner glass dielectric layer is stacked below the middle dielectric layer; the first patch is attached between the outer glass dielectric layer and the middle dielectric layer; the first patch is provided with four fan-shaped grooves penetrating through the thickness of the first patch; the second patch is attached between the middle dielectric layer and the inner glass dielectric layer; the second patch is provided with four linear grooves penetrating through the thickness of the second patch, and the four linear grooves are distributed in a cross shape; the fan-shaped grooves and the straight-line-shaped grooves are arranged in a one-to-one correspondence mode, and orthographic projections of the straight-line-shaped grooves are covered by orthographic projections of the fan-shaped grooves The feed patch is attached to the lower surface of the inner glass dielectric layer and is used for feeding; and the PCB layer is attached to the lower surface of the feed patch. The antenna covers two resonance points, and the antenna gain is high.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle-mounted antennas, and in particular to a dual-frequency automobile glass antenna applied to vehicle-mounted satellite navigation. Background Art

[0002] With the continuous development of 5G communication technology, the wave of intelligence has swept all walks of life. Intelligent driving technology has become a hot topic in the automotive industry and information technology field in recent years. Among them, satellite navigation function is a key link in intelligent driving technology, and a satellite navigation antenna with good performance is indispensable in the satellite navigation signal receiving system. At present, the satellite navigation antenna on the car mainly exists in the form of protruding from the outside of the vehicle or installed near the car dashboard.

[0003] The existing ones are either only applicable to single-band coverage of GPS; or applicable to dual-band coverage of GPS, but punching will seriously affect the original mechanical properties of the automotive glass, the structure is complex, the antenna gain is low, and the multi-layer structure of the automotive glass is not taken into account. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the above-mentioned problems existing in the prior art.

[0005] In order to solve the above technical problems, the present invention provides a dual-frequency automobile glass antenna applied to vehicle-mounted satellite navigation, comprising: Outer glass dielectric layer; An intermediate dielectric layer is stacked below the outer glass dielectric layer; An inner glass dielectric layer is stacked below the middle dielectric layer; A first patch is attached between the outer glass dielectric layer and the middle dielectric layer; the first patch is provided with four fan-shaped grooves penetrating the thickness thereof; The second patch is applied between the middle dielectric layer and the inner glass dielectric layer; the second patch is provided with four straight grooves running through the thickness thereof, the four straight grooves are arranged in a cross shape and are interconnected; the fan-shaped grooves are arranged one-to-one with the straight grooves, and the orthographic projection of the straight groove is covered by the orthographic projection of the fan-shaped groove; A feeding patch is attached to the lower surface of the inner glass dielectric layer and is used for feeding; The PCB board layer is attached to the lower surface of the feed patch.

[0006] In one embodiment of the present invention, the axis of the fan-shaped groove coincides with the axis of the straight-line groove.

[0007] In one embodiment of the present invention, the circular angle of the fan-shaped groove is 20° to 30°.

[0008] In one embodiment of the present invention, the feeding patches are four rectangular feeding patches, the four rectangular feeding patches are arranged at intervals of 90 degrees along the axial direction, and the phase difference between the four rectangular feeding patches is 90 degrees.

[0009] In one embodiment of the present invention, a circular ring groove is provided in the second patch at a position close to the outer wall thereof and runs through the thickness thereof, and a recess is formed on the circular ring groove at intervals of 90° toward the center of the second patch; the axis of the recess coincides with the axis of the I-shaped groove; and the recess matches the rectangular feeding patch.

[0010] In one embodiment of the present invention, the length of the straight groove is 0.31λr~0.34λr, and the width is 0.01λr~0.02λr; the radius of the fan-shaped groove is 0.15λr~0.16λr; wherein λr is the dielectric wavelength of the outer glass dielectric layer.

[0011] In one embodiment of the present invention, the calculation formula of the dielectric wavelength λr of the outer glass dielectric layer is: (Formula 1) (Formula 2) Where: λr is the dielectric wavelength of the outer glass dielectric layer; λ is the wavelength of the electromagnetic wave propagating in free space; ε r is the dielectric constant of the outer glass dielectric layer; c is the propagation speed of electromagnetic waves in free space; f is the frequency of electromagnetic waves.

[0012] In one embodiment of the present invention, the present application also includes a ground plane disposed at the bottom of the PCB board layer.

[0013] In one embodiment of the present invention, the PCB board layer is made of epoxy glass cloth laminate.

[0014] In one embodiment of the present invention, the intermediate medium layer is made of PVB glue.

[0015] Compared with the existing technology, it has the following advantages: The dual-frequency automobile glass antenna used for vehicle-mounted satellite navigation described in the present invention has a first patch arranged between the outer glass dielectric layer and the middle dielectric layer, a second patch arranged between the middle dielectric layer and the inner glass dielectric layer, four fan-shaped grooves arranged on the first patch, four straight grooves arranged on the second patch, and the orthographic projection of the straight groove is covered by the orthographic projection of the fan-shaped groove; due to the cooperation of the fan-shaped groove and the straight groove, the impedance matching performance of the present application is good, and two resonance points (i.e., a low-frequency resonance point and a high-frequency resonance point) can be covered. The resonance degree of each resonance point of the present application is much deeper than that of the comparative embodiment, the antenna gain of the antenna of the present application is high, the frequency band that the antenna can cover is wider, and the resonance degree is good; the present application adopts a stacked patch structure, reasonably utilizes the multi-layer structure of the automobile glass, and ensures the mechanical properties of the automobile glass without drilling holes, and realizes the low-profile dual-frequency coverage characteristics; the antenna structure is simpler, the reflection coefficient covers a wider frequency band and the axial ratio performance is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein: Figure 1 It is a three-dimensional schematic diagram of a dual-frequency automobile glass antenna applied to vehicle-mounted satellite navigation in a preferred embodiment of the present invention; Figure 2 yes Figure 1 Front view of dual-band automotive glass antenna for vehicle-mounted satellite navigation; Figure 3 yes Figure 1 A schematic diagram of the structure of the outer glass dielectric layer in a dual-frequency automotive glass antenna used for vehicle-mounted satellite navigation; Figure 4 yes Figure 1 A schematic diagram of the structure of the first patch in the dual-frequency automotive glass antenna used for vehicle-mounted satellite navigation; Figure 5 yes Figure 1 A schematic diagram of the structure of the second patch in the dual-frequency automobile glass antenna used for vehicle-mounted satellite navigation; Figure 6 yes Figure 1 A schematic diagram of the structure of the feed patch in the dual-frequency automotive glass antenna used for vehicle-mounted satellite navigation; Figure 7 1 is a comparison diagram of the simulated reflection coefficient characteristics of the comparative embodiment (without the straight groove and the fan-shaped groove) and the present application; Figure 8 This is a characteristic diagram of the reflection coefficient of the simulated antenna in this application; Fig. 9 This is a characteristic diagram of the axial ratio of the simulated antenna in this application; Fig.10 This is a graph of antenna gain characteristics simulated by this application; Fig.11 It is the two-dimensional radiation pattern of the antenna of the present application at 1.227 GHz; Fig.12 It is the two-dimensional radiation pattern of the antenna of the present application at 1.575 GHz; Description of the accompanying drawings: 100, outer glass dielectric layer; 200, intermediate dielectric layer; 300, inner glass dielectric layer; 400, first patch; 410, fan-shaped groove; 500, second patch; 510, straight groove; 520, annular groove; 530, recessed portion; 600, feed patch; 700, PCB board layer; 800, ground plane; 900. Feeding port. DETAILED DESCRIPTION

[0017] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0018] Reference Figure 1 to Figure 12 As shown, an embodiment of the present invention provides a dual-frequency automobile glass antenna applied to vehicle-mounted satellite navigation, comprising: Outer glass dielectric layer 100; The middle dielectric layer 200 is stacked below the outer glass dielectric layer 100 ; in some embodiments, the middle dielectric layer 200 is PVB (polyvinyl butyral) glue.

[0019] The inner glass dielectric layer 300 is stacked below the middle dielectric layer 200; The first patch 400 is attached between the outer glass dielectric layer 100 and the middle dielectric layer 200. The first patch 400 is provided with four fan-shaped grooves 410 running through the thickness thereof. The first patch 400 may be circular, hexagonal, rectangular or the like.

[0020] The second patch 500 is applied between the middle dielectric layer 200 and the inner glass dielectric layer 300; the second patch 500 is provided with four straight grooves 510 running through its thickness, and the four straight grooves 510 are arranged in a cross shape and are interconnected (i.e., the four straight grooves 510 form a cross groove); in some embodiments, the first patch 400 is a circular structure. The fan-shaped grooves 410 are arranged one-to-one with the straight grooves 510, and the orthographic projection of the straight groove 510 is covered by the orthographic projection of the fan-shaped grooves 410; A feeding patch 600 is attached to the lower surface of the inner glass dielectric layer 300 and is used for feeding; The PCB board layer 700 is attached to the lower surface of the feeding patch 600 and the inner glass dielectric layer 300 .

[0021] In some comparative embodiments, the antenna is mounted on the antenna, specifically by applying a patch on the glass of the skylight. Figure 7 The frequency and reflection coefficient of the comparative embodiment are simulated, and it can only achieve one resonance point (near 1.4GHz) and its resonance degree is slightly lower than -10 (the critical value of the reflection coefficient is -10, and the antenna can be used normally only when the reflection coefficient is lower than -10). It can be seen that the resonance degree of the comparative embodiment is shallow, resulting in a very narrow frequency band covered by the antenna and relatively poor reflection coefficient performance; the bandwidth of the antenna is greatly improved. This application adopts a stacked patch structure, which does not require drilling to ensure the mechanical properties of the automotive glass and achieves low-profile dual-frequency coverage characteristics.

[0022] In order to solve the problems of the above-mentioned comparative embodiment, the present application sets a first patch 400 between the outer glass dielectric layer 100 and the middle dielectric layer 200, sets a second patch 500 between the middle dielectric layer 200 and the inner glass dielectric layer 300, sets four fan-shaped grooves 410 on the first patch 400, sets four straight grooves 510 on the second patch 500, and the orthographic projection of the straight groove 510 is covered by the orthographic projection of the fan-shaped groove 410; due to the coordination of the fan-shaped groove 410 and the straight groove 510, the impedance matching performance of the present application is good, and it can cover two resonance points (i.e., a low-frequency resonance point and a high-frequency resonance point). The frequency and reflection coefficient of the present application are simulated, and the simulation results are shown in Figure 7 The reflection coefficients at the two resonance points are -15 and -20 (much lower than -10dB), and the resonance degree of each resonance point is much deeper than that of the comparative embodiment. The antenna gain of the antenna of the present application is high, the frequency band that can be covered is wider, the resonance degree is good, and the reflection coefficient performance is better. The present application adopts a stacked patch structure, rationally utilizes the multi-layer structure of the automobile glass, and ensures the mechanical properties of the automobile glass without drilling holes, and realizes the low-profile dual-frequency coverage characteristics; the antenna structure is simpler, the reflection coefficient covers a wider frequency band and has good axial ratio performance.

[0023] Furthermore, the axis of the fan-shaped slot 410 coincides with the axis of the straight slot 510. That is, the four fan-shaped slots 410 are arranged at 90° along the circumferential direction. Specifically, this embodiment enables the first patch 400 to generate an orthogonal current inclined at 45°, and the horizontal component and vertical component of the electric field corresponding to the current have equal amplitudes, and the phase difference of 90° can generate a right-hand circularly polarized wave, so that the axial ratio performance of the present application is better.

[0024] Furthermore, the circular angle of the fan-shaped slot 410 is 20° to 30°. Specifically, this embodiment makes the performance of the antenna better.

[0025] Further, the feeding patch 600 is four rectangular feeding patches 600, and the four rectangular feeding patches 600 are arranged at 90 degree intervals along the axial direction, and the phase difference of the four rectangular feeding patches 600 is 90°. A circular ring groove 520 is provided at a position close to the outer wall of the second patch 500, which runs through its thickness. The circular ring groove 520 is recessed toward the center of the second patch 500 at intervals of 90° to form a recessed portion 530; the axis of the recessed portion 530 coincides with the axis of the straight groove 510; the recessed portion 530 matches the rectangular feeding patch 600. Specifically, the four feeding patches 600 in this embodiment are coupled and fed to the circular ring groove 520 of the second patch 500 of the upper layer with a phase difference of 90°, and the energy is transmitted to the second patch 500, and the feeding effect is better. The rectangular feeding patch 600 is connected to the ground plane 800 (described below) through an ideal feeding port 900 for feeding.

[0026] Furthermore, the length of the straight groove 510 is 0.31λr~0.34λr (29~32mm), and the width is 0.01λr~0.02λr (1~2mm); the radius R4 of the fan-shaped groove 410 is 0.15λr~0.16λr (14~15mm), where the dielectric wavelength of the outer glass dielectric layer 100. The first patch 400 is circular, and the radius R3 of the first patch 400 is 0.18λr~0.2λr (17~19mm). In some embodiments, in order to ensure the stability of the structure of the first patch 400, the first patch 400 is provided with a circular disc at the center of the array of four fan-shaped circular arrays, and the radius R5 of the circular disc is 0.02λr~0.05λr (2~5mm).

[0027] In some specific embodiments, see Figure 2~Figure 6, the overall size of the antenna is 90mm×90mm×9.36mm (0.38λ×0.38λ×0.039λ). The inner glass dielectric layer 300 has the same size as the outer glass dielectric layer 100. The thickness of the outer glass dielectric layer 100 is H1=2mm. The thickness of the intermediate dielectric layer 200 is H2=0.76mm. The thickness of the PCB board layer 700 is H3=4.6mm. The radius of the annular groove 520 is R1=20mm. The radius of the first patch 400 is R3=17mm. The radius of the fan-shaped groove 410 is R4=15mm. The radius of the disc is R5=2mm. The central angle a1 of the fan-shaped groove 410 is 25°. The length LX and width LY of the outer glass dielectric layer are: LX=90mm, LY=90mm. The length and width of the rectangular feeding patch 600 are: Pf=9mm, Wf=3mm respectively. The relevant dimensions of the recessed portion 530 are: L1=4mm; L2=3.5mm; W1=4mm; W2=3mm; W=1mm; D=4mm. The sum of the lengths of the two coaxial straight grooves 510 is S1=30mm; and the width of the straight groove 510 is WS=1.5mm.

[0028] The specific embodiment is simulated to obtain the following chart: 1. Antenna reflection coefficient characteristics, see Figure 8 As can be seen from the figure, this embodiment has two resonance points, namely the low-frequency resonance point (1.22GHz) and the high-frequency resonance point (1.58GHz). It can be seen that this embodiment can cover the L2 (1.227GHz) and L1 (1.575GHz) frequency bands of satellite navigation. And the reflection coefficients of this embodiment at the 1.22GHz resonance point and the 1.58GHz resonance point are -13.5919 and -14.37975 respectively. The frequency band covered by the antenna of this application is wider and the reflection coefficient performance is better.

[0029] 2. Antenna axial ratio characteristics, see Fig. 9 The axial ratio reflects the circular polarization performance. Only when it is below 3.0dB can the circular polarization performance requirements of the antenna be met. Fig. 9 It can be seen that the axial ratio corresponding to the low-frequency resonance point (1.22GHz) and the high-frequency resonance point (1.58GHz) is far less than 3.0dB, which shows that the axial ratio characteristics of this embodiment are excellent. In addition, the antenna axial ratio bandwidth performance of this embodiment is good and can cover 1~2GHz.

[0030] 3. Antenna gain characteristics, see Fig.10 ; Gain can reflect the intensity of the antenna's transmitted energy, and the existing technology can reach 0dB. Fig.10It can be seen that the gains of this embodiment at the 1.22 GHz resonance point and the 1.58 GHz resonance point are 1.13355 dB and 3.13792 dB, respectively. It can be seen that the gain characteristics of this embodiment are excellent.

[0031] 4. The two-dimensional radiation pattern of the antenna at the low-frequency resonance point (1.227GHz) is shown in Fig.11 , this figure can reflect the shape of the antenna radiation, and its gain is 1.13228. The main radiation direction of the antenna is directly above +z direction. Directly above is right-hand circular polarization, with wide beam characteristics and good cross-polarization characteristics.

[0032] 5. Two-dimensional radiation pattern at the high-frequency resonance point of the antenna (1.575GHz), see Fig.12 ; This figure can reflect the shape of the antenna radiation. Its gain is 3.13347. The main radiation direction of the antenna is in the +z direction directly above. The right circular polarization is directly above, and it has a wide beam characteristic. And good cross polarization characteristics .

[0033] Specifically, the two resonance points of the present application are located at 1.22 GHz and 1.58 GHz respectively, and the energy of the present application can be concentrated at the required frequency point.

[0034] It should be noted that the impedance matching of the present application can be adjusted by adjusting the diameter and the central angle of the fan-shaped slot 410 and the length of the straight slot 510, thereby achieving the regulation of the resonance point.

[0035] Furthermore, the calculation formula of the medium wavelength λr is: (Formula 1) (Formula 2) Where: λr is the dielectric wavelength of the outer glass dielectric layer 100; λ is the wavelength of the electromagnetic wave propagating in free space; ε r is the dielectric constant of the outer glass dielectric layer 100; c is the propagation speed of electromagnetic waves in free space; and f is the frequency of the electromagnetic waves.

[0036] In some comparative embodiments, the antenna radiation direction is bidirectional radiation, so half of the energy will be radiated downward, resulting in energy waste, which leads to low gain of the antenna and is difficult to meet the design requirements of the satellite navigation antenna. In view of the above problems, further, the present application also includes a ground plane 800 arranged at the bottom of the PCB board layer 700. Specifically, the present embodiment adopts a laminated patch and sets a ground plane 800, so that the present application is directional radiation, achieves high gain, and thus reduces energy waste. In some possible implementations, the ground plane 800 is a layer of copper foil.

[0037] Furthermore, the PCB board layer 700 is made of epoxy glass cloth laminate, and the PCB board layer 700 and the inner glass dielectric layer 300 are bonded with glue.

[0038] In some embodiments, the first patch 400 , the second patch 500 , and the feeding patch 600 are printed using silver paste.

[0039] In actual production, space is reserved under the antenna for the RF receiving circuit part of the vehicle-mounted satellite navigation system.

[0040] In some embodiments, the thickness of the PCB layer 700 may be 4.6 mm, the relative dielectric constant may be 4.4, and the loss tangent may be 0.02. The thickness of the inner glass dielectric layer 300 and the outer glass dielectric layer 100 may be the same, for example, the thickness may be 0.76 mm; the material of the inner glass dielectric layer 300 and the outer glass dielectric layer 100 may also be the same, for example, the relative dielectric constant may be 2.96, and the loss tangent may be 0.06.

[0041] This application makes reasonable use of the multi-layer structure of the skylight glass, adds different radiation patches (first patch 400, second patch 500) between different interlayers, and adds a PCB board layer 700 under the skylight glass, and finally designs a vehicle-mounted dual-band automotive glass antenna. The antenna can achieve right-hand circular polarization coverage of two frequencies of 1.227GHz and 1.575GHz, and has relatively good performance. This application has the characteristics of high gain and directional radiation; the main radiation direction of the antenna of this application is directly above, and the energy is concentrated.

[0042] In some comparative embodiments, the antenna is set on the automobile glass, which can cover a narrow satellite navigation frequency band and has a complex antenna structure, which occupies a large area and is difficult to achieve a miniaturized design of the structure. The axial ratio bandwidth is narrow and is only applicable to a single-layer glass structure. The multi-layer glass structure of the actual automobile sunroof is not considered, which has a great impact on the antenna gain and other performance when used. In order to solve this problem, this application proposes a design idea of ​​integrating antenna components with glass, which reasonably utilizes the multi-layer glass structure of the automobile sunroof glass, has a compact structure, a wide working bandwidth, and a high gain.

[0043] In some comparative embodiments, there are usually two technical solutions for laminated structure satellite navigation antennas. One is to use coaxial feeding. Although broadband coverage can be achieved, drilling will seriously affect the original mechanical properties of the automotive glass. The other is to use coupled feeding. Although this method does not require vias and has good dual-frequency coverage performance, it has high profile requirements and the air layer is as high as 10mm, which is difficult to apply to low-profile automotive glass antenna designs. The present application uses stacked patches and coupled feeding technology to couple and feed the upper radiation patch (the second patch 500) and the first patch 400 through the four rectangular feeding patches 600 at the bottom layer, thereby realizing a high-gain, directional radiation, low-profile dual-frequency circularly polarized patch antenna design with a relatively wide working bandwidth; thereby avoiding the via structure from affecting the mechanical properties of the automotive glass while achieving low-profile dual-frequency coverage characteristics.

[0044] In some comparative embodiments, the antenna is arranged outside the car or for the built-in navigation antenna; the antenna is arranged outside the car (for example, the traditional shark fin structure, multiple antennas are integrated inside, and it is mainly used in MIMO-LTE, GPS, WLAN and other frequency bands, among which the GPS navigation antenna adopts the traditional patch structure to achieve coverage of the 1575MHz frequency band. The structure is relatively complex, and there is large mutual coupling interference between the multiple antennas inside. The cross-sectional height of the antenna is 55mm) is easily affected by external environmental factors such as rain, snow and other weather, and the shark fin antenna often integrates multiple antennas together, resulting in mutual interference between antennas, causing performance deterioration. For the built-in navigation antenna, it is susceptible to electromagnetic interference from surrounding electronic components and electromagnetic shielding brought by the car body, resulting in degradation of antenna system performance. In order to solve this problem, since the present application sets the antenna on the vehicle sunroof, it is relatively far away from other electronic components, is less subject to electromagnetic interference, has a low vehicle drag coefficient, and is highly aesthetic.

[0045] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A dual-frequency automotive glass antenna for vehicle-mounted satellite navigation, characterized in that: include: Outer glass dielectric layer; An intermediate dielectric layer, stacked below the outer glass dielectric layer; An inner glass dielectric layer, stacked below the middle dielectric layer; A first patch, applied between the outer glass dielectric layer and the middle dielectric layer; the first patch is provided with four fan-shaped grooves penetrating the thickness thereof; A second patch is applied between the intermediate dielectric layer and the inner glass dielectric layer; the second patch is provided with four straight grooves running through the thickness thereof, the four straight grooves are arranged in a cross shape and are interconnected; the fan-shaped grooves are arranged in a one-to-one correspondence with the straight grooves, and the orthographic projection of the straight groove is covered by the orthographic projection of the fan-shaped grooves; A feeding patch, attached to the lower surface of the inner glass dielectric layer, for feeding; The PCB board layer is attached to the lower surface of the feeding patch.

2. The dual-frequency automobile glass antenna for vehicle-mounted satellite navigation according to claim 1, characterized in that: The axis of the fan-shaped groove coincides with the axis of the straight groove.

3. The dual-frequency automobile glass antenna for vehicle-mounted satellite navigation according to claim 1, characterized in that: The circular angle of the fan-shaped groove is 20° to 30°.

4. The dual-frequency automobile glass antenna for vehicle-mounted satellite navigation according to claim 1, characterized in that: The feeding patches are four rectangular feeding patches, which are arranged at intervals of 90 degrees along the axial direction, and the phase difference between the four rectangular feeding patches is 90 degrees.

5. The dual-frequency automobile glass antenna for vehicle-mounted satellite navigation according to claim 4, characterized in that: A circular ring groove is provided in the second patch at a position close to the outer wall thereof and runs through the thickness thereof, and the circular ring groove is recessed toward the center of the second patch at intervals of 90° to form a recessed portion; the axis of the recessed portion coincides with the axis of the I-shaped groove; and the recessed portion matches the rectangular feeding patch.

6. The dual-frequency automobile glass antenna for vehicle-mounted satellite navigation according to claim 1, characterized in that: The length of the straight groove is 0.31λr~0.34λr, and the width is 0.01λr~0.02λr; the radius of the fan-shaped groove is 0.15λr~0.16λr; wherein λr is the dielectric wavelength of the outer glass dielectric layer.

7. The dual-frequency automobile glass antenna for vehicle-mounted satellite navigation according to claim 6, characterized in that: The calculation formula of medium wavelength λr is: (Formula 1) (Formula 2) Where: λr is the dielectric wavelength of the outer glass dielectric layer; λ is the wavelength of the electromagnetic wave propagating in free space; ε r is the dielectric constant of the outer glass dielectric layer; c is the propagation speed of electromagnetic waves in free space; f is the frequency of electromagnetic waves.

8. The dual-frequency automobile glass antenna for vehicle-mounted satellite navigation according to claim 1, characterized in that: It also includes a ground plane arranged at the bottom of the PCB board layer.

9. The dual-frequency automobile glass antenna for vehicle-mounted satellite navigation according to claim 1, characterized in that: The PCB board layer is made of epoxy glass cloth laminate.

10. The dual-frequency automobile glass antenna for vehicle-mounted satellite navigation according to claim 1, characterized in that: The intermediate medium layer is made of PVB glue.

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