Polarization-adjustable double-frequency transparent flexible antenna and wireless communication equipment

Abstract

The invention discloses a polarization-adjustable double-frequency transparent flexible antenna and wireless communication equipment, the polarization-adjustable double-frequency transparent flexible antenna is made of a flexible conductive material and comprises an antenna ground and two circular patches, the two circular patches are symmetrically arranged about a straight line, an annular gap is formed between the circular patches and the antenna ground, and the circular patches are arranged in the annular gap. T-shaped feeder lines and a one-to-two power division line are arranged on one side of the circular patch, and three switching diodes are respectively connected between the two T-shaped feeder lines and the one-to-two power division line; a feed branch knot of the one-to-two power division line is connected with the coaxial connector; the antenna can be attached to transparent glass to realize invisibility conformal, in order to solve polarization attenuation generated in a complex vehicle-mounted communication environment and improve the anti-interference performance, the on-off state of a switching diode is adopted to control the current distribution and flow direction of the antenna, horizontal polarization, vertical polarization, left-hand circular polarization and right-hand circular polarization are adjustable in two frequency bands of 2.5 GHz and 5.8 GHz, and the antenna can be applied to a vehicle-mounted communication system. The design has the advantages of ultra-low profile, simple structure, easiness in processing, low cost, good performance and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of antennas, and in particular relates to a polarization-adjustable dual-frequency transparent flexible antenna and wireless communication equipment. Background Art

[0002] In contemporary society, as the trend of automotive electronics has significantly increased, in-vehicle wireless communication equipment, as a core component, has requirements including high-speed transmission capabilities, low interference characteristics and concealed design. Given the inherent transparent properties of vehicle glass (such as windshields or windows), they are ideal locations for antenna installation, allowing communication systems to be seamlessly integrated into vehicle design, thereby optimizing user experience. However, traditional antenna technology faces many challenges in such application environments, such as limited installation space, reduced contrast and potential interference with the driver's vision.

[0003] Traditional vehicle-mounted antennas are usually designed with fixed structures, which makes it impossible for them to adjust the direction or frequency band according to the changes in the vehicle shape. This may have an adverse effect on the communication quality in a changing road environment. In addition, in complex electromagnetic environments such as cities, multipath fading and polarization attenuation are also common, and even different weather conditions have a negative effect on the propagation of electromagnetic waves, further reducing the communication quality.

[0004] In view of the above problems, the polarization-adjustable dual-frequency transparent flexible antenna described in the present invention provides a solution. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention provides a polarization-adjustable dual-frequency transparent flexible antenna for vehicle-mounted communications. The antenna is made of a flexible transparent conductive film and can be attached to transparent glass to achieve invisible conformality. In order to solve the polarization attenuation generated in the complex environment of vehicle-mounted communications and improve the anti-interference performance, the antenna uses the on-off state of a switching diode to control the current distribution and flow direction of the antenna, so as to achieve adjustable horizontal polarization, vertical polarization, left-hand circular polarization, and right-hand circular polarization in the two frequency bands of 2.5GHz and 5.8GHz. The design has the advantages of ultra-low profile, simple structure, easy processing, low cost, good performance, etc.

[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a polarization adjustable dual-band transparent flexible antenna, made of flexible conductive material, including an antenna ground and two circular patches, the two circular patches are arranged symmetrically about a straight line, there is an annular gap between the circular patch and the antenna ground, a T-type feeder and a one-way two-power splitting line are arranged on one side of the circular patch, a switching diode is connected between the two T-type feeders and the one-way two-power splitting line respectively; a switching diode is connected to the antenna ground and the two ends of the one-way two-power splitting line respectively; the feeding branch of the one-way two-power splitting line is connected to a coaxial connector.

[0007] Furthermore, the center distance of the circular patch is greater than the diameter of the circular patch.

[0008] Furthermore, the switching diode includes a first switching diode, a second switching diode, a third switching diode, and a fourth switching diode; the first switching diode and the third switching diode are symmetrically arranged, the second switching diode and the fourth switching diode are symmetrically arranged, the positive poles of the first switching diode and the second switching diode are connected to the one-to-two power distribution line, the negative pole of the first switching diode is connected to the antenna ground, and the negative pole of the second switching diode is connected to the T-type feeder.

[0009] Further, working condition 1: when the first switch diode and the third switch diode are disconnected and the second switch diode and the fourth switch diode are connected, the current is coupled and fed to the two circular patches through the one-to-two power splitting line; the operating frequency is 2.4 GHz to 6.5 GHz, and at the same time, far-field radiation with linear polarization in the y direction is formed in this frequency band;

[0010] Working condition 2: when the first switch diode is connected and the second, third and fourth switch diodes are disconnected, the current feeds the two circular patches through the one-to-two power splitter line; it works at 2.5 GHz and 5.8 GHz, and at the same time forms x-direction linear polarization far-field radiation at 2.5 GHz and left-hand circular polarization radiation at 5.8 GHz;

[0011] Working condition 3: When the third switch diode is connected and the first, second and fourth switch diodes are disconnected, the current feeds the two circular patches through the one-to-two power splitter line, and operates at 2.5 GHz and 5.8 GHz. At the same time, x-direction linear polarization far-field radiation is formed at 2.5 GHz, and right-hand circular polarization radiation is formed at 5.8 GHz.

[0012] Furthermore, the longitudinal section of the T-type feeder is connected to the one-to-two power splitter, the transverse section of the T-type feeder is coupled to the circular patch, and the transverse section of the T-type feeder is arc-shaped.

[0013] Furthermore, it is manufactured by an etching process, a laser engraving process or a mask deposition process.

[0014] Furthermore, PET polyester is used as the substrate, and the flexible conductive material is an ITO indium tin oxide conductive flexible film, the square resistance does not exceed 6Ω, and the transmittance is not less than 87%.

[0015] Furthermore, the material and forming method of the one-to-two power distribution line and the antenna ground are the same, and there is a gap between the one-to-two power distribution line and the antenna ground.

[0016] The two circular patches and the T-type feeder are arranged symmetrically about the perpendicular bisector of the line connecting the centers of the circular patches.

[0017] In addition, the present invention can also provide a wireless communication device, which adopts the above-mentioned polarization adjustable dual-frequency transparent flexible antenna.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects: the present invention proposes a polarization-adjustable dual-frequency transparent flexible antenna for vehicle-mounted communications, which simultaneously realizes dual-band and polarization-adjustable performance; a switching diode is used to realize that the dual-band antenna is adjustable in x-direction linear polarization, y-direction linear polarization, left-hand circular polarization, and right-hand circular polarization, respectively, and different switching conditions and frequencies correspond to different radiation modes, which solves the polarization attenuation generated in the complex environment of vehicle-mounted communications and improves anti-interference performance; the polarization-adjustable dual-frequency transparent flexible antenna of the present invention operates at 2.5GHz and 5.8GHz, covering Bluetooth, Wifi and ISM industrial, scientific and medical frequency bands, and providing high-speed broadband communication services for the Internet of Things, etc.; the polarization-adjustable dual-frequency transparent flexible antenna of the present invention utilizes a coplanar waveguide feeding mode to realize an ultra-low profile antenna structure, with a simple overall design, light weight, transparent and invisible, and easy processing, and can be used in vehicle-mounted glass, smart homes or other communication scenarios requiring invisible conformality. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the three-dimensional structure of the polarization-adjustable dual-frequency transparent flexible antenna of the present invention;

[0020] Figure 2 It is a top plan view of the polarization adjustable dual-frequency transparent flexible antenna of the present invention;

[0021] Figure 3 a is an equivalent circuit of the coplanar waveguide feeding structure of the polarization-adjustable dual-frequency transparent flexible antenna of the present invention;

[0022] Figure 3 b is an equivalent circuit of the working condition 1 of the polarization adjustable dual-frequency transparent flexible antenna of the present invention;

[0023] Figure 3 c is the equivalent circuit of the working condition 2 of the polarization adjustable dual-frequency transparent flexible antenna of the present invention;

[0024] Figure 3 d is the working condition three equivalent circuits of the polarization adjustable dual-frequency transparent flexible antenna of the present invention;

[0025] Figure 4 is a graph of S parameter results of the antenna on glass when the port is fed according to an embodiment of the present invention;

[0026] Figure 5 is a graph of gain results on glass when the port is fed with power according to an embodiment of the present invention;

[0027] Figure 6 is a result diagram of the circular polarization axis ratio on glass when the port is fed with power in an embodiment of the present invention;

[0028] Figure 7 The embodiment of the present invention adopts the "y-direction linear polarization / y-direction linear polarization" working condition - xoz and yoz plane radiation patterns at different frequencies;

[0029] Figure 8a The embodiment of the present invention adopts the xoz and yoz plane radiation patterns at different frequencies of the second working condition of "x-direction linear polarization / left-hand circular polarization";

[0030] Figure 8b The embodiment of the present invention adopts the "x-direction linear polarization / left-hand circular polarization" working condition 2 at 5.8 GHz of the xoz and yoz plane radiation patterns of the circular polarization component;

[0031] Figure 9a The embodiment of the present invention adopts the xoz and yoz plane radiation patterns at different frequencies under the working condition of "x-direction linear polarization / right-hand circular polarization";

[0032] Figure 9b The embodiment of the present invention adopts the "x-direction linear polarization / right-hand circular polarization" working condition three at 5.8GHz circular polarization component xoz and yoz plane radiation patterns.

[0033] In the attached drawings, 1-coaxial connector, 21-first switch diode, 22-second switch diode, 3-antenna ground, 4-T-type feeder, 5-circular patch, 6-annular gap, 71-third switch diode, 72-fourth switch diode, 8-one-to-two power distribution line. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] In the description of the present invention, it should be understood that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "bottom", "one side", "one end" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0036] The present invention provides a polarization adjustable dual-frequency transparent flexible antenna, such as Figure 1 As shown, it can be formed by etching a flexible transparent conductive material, including two circular patches 5 and a feeding structure, and an annular gap 6 is engraved between the circular patch 5 and the antenna ground 3, and the circular patch 5 is coupled and fed through the T-type feeder 4. The T-type feeder 4 is connected to the one-to-two power splitter 8 through the switching diodes 22 and 72. The second switching diode 22 and the fourth switching diode 72 are set at the interface of the T-type feeder 4 and the one-to-two power splitter 8, the first switching diode 21 and the third switching diode 71 are connected to the one-to-two power splitter 8 and the antenna ground 3, and the coaxial connector 1 is used to feed and excite the one-to-two power splitter 8.

[0037] The two circular patches 5 and the T-shaped feed line 4 are arranged symmetrically about the perpendicular bisector of the line connecting the centers of the circular patches 5 .

[0038] The polarization adjustable dual-frequency transparent flexible antenna of the present invention is made by etching process, laser engraving process or mask deposition process. The antenna material includes but is not limited to ITO indium tin oxide conductive flexible film with PET polyester as the base material. The square resistance of the transparent material is 6 ohms. The overall thickness of the antenna is 0.188mm and the transmittance is 87%. The top view of the antenna is shown in FIG. Figure 2 As shown, the size is W×L, the radius of the circular patch 5 is R2, the radius of the annular gap 6 surrounding the circular patch 5 is R1, the center distance between the two circular patches 5 is d, and the distance from the center point of the circular patch 5 to the long side L is dc. The radius of the upper edge of the curved branch of the T-type feeder 4 is R4, the radius of the lower edge is R3, and the length and width of the vertical patch of the T-type feeder 4 are lf1 and wf1 respectively. The length and width of the one-to-two power splitter 8 are lf2 and wf2 respectively, and the gap distance between it and the antenna ground 3 is gf. In addition, the length of the feeding branch of the one-to-two power splitter 8 is wg and the width is wf0. The feeding branch of the one-to-two power splitter 8 is connected to the coaxial connector 1.

[0039] The working principle of the polarization adjustable dual-frequency transparent flexible antenna of the present invention is as follows:

[0040] The antenna of the present invention adopts a dual-unit array antenna form to improve the radiation gain. The electromagnetic wave signal is fed through the coaxial connector 1. When the second switch diode 22 and the fourth switch diode 72 are connected, and the first switch diode 21 and the third switch diode 71 are disconnected, it is called working condition 1. The current is coupled and fed to the two circular patches 5 through the one-to-two power splitter 8. At this time, the dominant current of the antenna flows through the T-type feed and the circular patch to form a linearly polarized electric field change. Figure 4 As shown, the reflection parameters of the antenna work in the range of 2.4 GHz to 6.5 GHz, with a broadband working frequency band. At the same time, far-field radiation with linear polarization in the y direction is formed in the two frequency bands of 2.5 GHz and 5.8 GHz.

[0041] When the first switch diode 21 is connected, and the second switch diode 22, the third switch diode 71 and the fourth switch diode 72 are disconnected, it is called working condition 2. At this time, the main current of the antenna flows out from the left end of the one-to-two power splitter 8, presents a high-order mode distribution around the loop antenna ground 3, and flows in from the right end of the one-to-two power splitter 8, forming a left-hand circularly polarized electric field change in the z direction. The reflection parameters of the antenna are as follows: Figure 4 As shown, it works at 2.5 GHz and 5.8 GHz respectively, and forms x-direction linear polarization far-field radiation at 2.5 GHz and left-hand circular polarization radiation at 5.8 GHz, with multi-band and multi-polarization working capabilities.

[0042] When the third switch diode 71 is connected, the first switch diode 21, the second switch diode 22 and the fourth switch diode 72 are disconnected, which is called working condition 3. At this time, the main current of the antenna flows out from the right end of the one-to-two power splitter 8, presents a high-order mode distribution around the loop antenna ground 3, flows in from the right end of the one-to-two power splitter 8, and forms a right-hand circularly polarized electric field change in the z direction. The reflection parameters of the antenna are as follows: Figure 4 As shown, it works at 2.5 GHz and 5.8 GHz respectively. At the same time, x-direction linear polarization far-field radiation is formed at 2.5 GHz, and right-hand circular polarization radiation is formed at 5.8 GHz. All working conditions and polarization modes of each frequency band are listed in Table 1.

[0043] Table 1

[0044] Switching diode 21 22&72 71 2.5GHz Polarization 5.8GHz Polarization Working condition 1 0 1 0 Linear polarization in y direction Linear polarization in y direction Working condition 2 1 0 0 Linear polarization in x direction Left-hand circular polarization Working condition three 0 0 1 Linear polarization in x direction Right-hand circular polarization

[0045] In order to explain the working principle of the antenna of the present invention in more depth, Figure 3 The equivalent circuit is given. The coplanar waveguide feeding structure of the antenna is equivalent to Figure 3In order to facilitate analysis, the T-type circuit in a is equivalent to the switch and load circuit by connecting the one-to-two power distribution line 8 and the diode switch connection unit structure, in which the two arms of the T-type circuit are connected in series L f1 and R f1 , T-type circuit center parallel C l1 The terminal cascade switch structure is connected to the corresponding equivalent circuit under different working conditions. Figure 3 b shows a dual-frequency resonant circuit with linear polarization in the y direction, where the low-frequency resonance is represented by a series RLC circuit, including L l1 , R l1 and C l1 The high frequency resonance is caused by the parallel connection of L h1 The component indicates that the frequency moves toward high frequency. Figure 3 In c and 3d, the operating frequency of 2.5 GHz is still represented by a series RLC circuit with linear polarization in the x direction, including the equivalent inductance L l2 , equivalent resistance R l2 And the equivalent capacitance C l2 , while the high frequency circular polarization equivalent circuit is represented by a parallel RLC circuit, including the equivalent inductance L h2 , equivalent resistance R h2 And the equivalent capacitance C h2 , to form a dual-frequency working mode. Here, the high-frequency left-handed and right-handed circular polarizations are only phase differences, with equal electric field strengths, so their equivalent circuit element parameters are equal. According to the equivalent circuits under different working conditions, the impedance calculation formula is given as follows:

[0046]

[0047] Where Z case-1 is the branch impedance at the moment of working condition 1, Z case-2 is the branch impedance in working condition 2, Z case-3 is the branch impedance under working condition three, and Z is the total circuit input impedance.

[0048] The transparent flexible antenna of the present invention operates in dual frequency bands of 2.5 GHz and 5.8 GHz, and has the performance of adjustable polarization in the dual frequency bands.

[0049] Figure 3 a is the equivalent circuit of the coplanar waveguide feeding structure when the antenna of the embodiment of the present invention is fed. The T-type structure can represent the input impedance of the coplanar waveguide structure, and the load is a switching diode; Figure 3 b is an equivalent circuit of the antenna structure of the embodiment of the present invention when the antenna is fed under the working condition 1 of "linear polarization in the y direction / linear polarization in the y direction (010)", which is a series RLC circuit; Figure 3c is an equivalent circuit of the antenna structure of the embodiment of the present invention when the antenna is fed under the second working condition of "x-direction linear polarization / left-hand circular polarization (100)", the low-frequency resonance mode is a series RLC circuit, and the high-frequency resonance mode is a parallel RLC circuit; Figure 3 d is the equivalent circuit of the antenna structure under the working condition three of "x-direction linear polarization / right-hand circular polarization (100)" when the antenna of the embodiment of the present invention is fed. Since only the phase is different from that of working condition two, the equivalent circuit is consistent with working condition two.

[0050] Figure 4 When feeding the antenna of the embodiment of the present invention, S 11 The simulation results are as follows. Under the working condition 1 of "y-direction linear polarization / y-direction linear polarization (010)", the dual-band transparent flexible antenna covers 2.4GHz~6.5GHz, the reflection coefficient is less than 10dB, and the relative bandwidth is 92%. Under the working condition 2 of "x-direction linear polarization / left-hand circular polarization (100)", it covers 2.24GHz~3.16GHz, 5.18GHz-6.5GHz, the reflection coefficient is less than 10dB, and the relative bandwidth is 34% and 22.6% respectively. Under the working condition 3 of "x-direction linear polarization / right-hand circular polarization (001)", it covers 2.25GHz~3.16GHz, 5.20GHz~6.5GHz, the reflection coefficient is less than 10dB, and the relative bandwidth is 33.7% and 22.2% respectively.

[0051] Figure 5 The simulation results of the actual far-field gain changing with frequency when feeding the antenna of the embodiment of the present invention. It can be seen that under the working condition 1 of "linear polarization in the y direction / linear polarization in the y direction (010)", the gains of the antenna at 2.5 GHz and 5.8 GHz are 4.36 dBi and 5.28 dBi respectively. Under the working condition 2 of "linear polarization in the x direction / left-hand circular polarization (100)", the gains of the antenna at 2.5 GHz and 5.8 GHz are 5.20 dBi and 5.33 dBi respectively. Under the working condition 3 of "linear polarization in the x direction / right-hand circular polarization (001)", the gains of the antenna at 2.5 GHz and 5.8 GHz are 5.25 dBi and 6.06 dBi respectively.

[0052] Figure 6 When feeding the antenna of the embodiment of the present invention, the circular polarization axis ratio results. It can be seen that under the working condition 1 of "linear polarization in the y direction / linear polarization in the y direction (010)", the circular polarization axis ratio of the antenna is above 35dB in the entire working frequency band, and the antenna is a linear polarization radiation mode. Under the working condition 2 of "linear polarization in the x direction / left-hand circular polarization (100)" and the working condition 3 of "linear polarization in the x direction / right-hand circular polarization (001)", the circular polarization axis ratio of 5.8GHz is less than 3dB, and the circular polarization bandwidth is 5.4GHz to 6.4GHz, indicating that this frequency band has good circular polarization performance.

[0053] Figure 7 When feeding the antenna of the embodiment of the present invention, the "y-direction linear polarization / y-direction linear polarization (010)" working condition 1 has xoz and yoz plane radiation patterns at different frequencies. Since the antenna is symmetrical on both sides and uses a coplanar waveguide feeding method, the far-field radiation pattern of the antenna is symmetrical up and down and left and right.

[0054] Figure 8a The embodiment of the present invention adopts the xoz and yoz plane radiation patterns at different frequencies of the working condition 2 of "x-direction linear polarization / / left-hand circular polarization (100)"; Figure 8b The embodiment of the present invention adopts the xoz and yoz plane radiation diagrams of the circular polarization component at 5.8GHz under the second working condition of "x-direction linear polarization / / left-hand circular polarization (100)". As can be seen from the figure, when θ = 0°, the left-hand circular polarization LHCP component is much larger than the right-hand circular polarization RHCP component, so the polarization mode of the θ = 0° antenna is left-hand circular polarization LHCP. When θ = 180°, the left-hand circular polarization LHCP component is much smaller than the right-hand circular polarization RHCP component, so the polarization mode of the θ = 180° antenna is right-hand circular polarization RHCP. The polarization mode when θ = 0° is taken by default in the present invention.

[0055] Figure 9a The embodiment of the present invention adopts the xoz and yoz plane radiation patterns at different frequencies under the working condition of "x-direction linear polarization / right-hand circular polarization (001)". Figure 9b The embodiment of the present invention adopts the xoz and yoz plane radiation diagram of the circular polarization component at 5.8GHz under the working condition three of "x-direction linear polarization / right-hand circular polarization (001)". It can be seen from the figure that when θ=0°, the right-hand circular polarization RHCP component is much larger than the left-hand circular polarization LHCP component, so the polarization mode of the θ=0° antenna is right-hand circular polarization RHCP.

[0056] The material of the polarization adjustable dual-frequency transparent flexible antenna provided by the present invention includes an ITO indium tin oxide conductive flexible film with PET polyester as the base material, the square resistance of the transparent material is 6 ohms, the overall thickness of the antenna is 0.188mm, and the transmittance is 87%. After optimized design, the specific geometric parameters are: antenna width W = 68.9mm, antenna length L = 96.7mm, distance dc from the center point of the circular patch 5 to the long side L = 28mm, center distance d between two circular patches 5 = 41.2mm, radius R1 of the annular gap 6 = 23mm, radius R2 of the circular patch 5 = 13mm, arc radius R3 of the lower edge of the curved branch of the T-type feeder 4 = 14.9mm, arc radius R4 of the upper edge of the curved branch of the T-type feeder 4 = 14.9mm, and arc radius R5 of the upper edge of the curved branch of the T-type feeder 4 = 14.9mm. R4=13.5mm, the vertical patch length lf1 of the T-type feed line 4=11.0mm, the length lf2 of the one-way power splitting line 8=49.2mm, the feeding branch width wf0 of the one-way power splitting line 8=5mm, the vertical patch width wf1 of the T-type feed line 4=4.0mm, the width wf2 of the one-way power splitting line 8=8mm, the feeding branch length wg of the one-way power splitting line 8=3.6mm, and the gap spacing gf between the one-way power splitting line 8 and the antenna ground 3=0.3mm.

[0057] Zinc oxide can also be used as a flexible conductive material. Chemical etching or plasma etching is used to remove unnecessary oxide materials, leaving only the portion forming the antenna pattern. After etching is completed, the substrate is cleaned and dried to remove residual etching solution and other impurities.

[0058] The antenna can not only adapt to the structure of different vehicles and achieve flexible deployment, but also improve directivity and anti-interference by controlling the polarization direction of electromagnetic waves. The dual-band design enables the antenna to simultaneously support Bluetooth, Wifi and ISM industrial science and medical frequency band communication standards, providing a wider range of spectrum resources to meet the needs of various communication scenarios. In addition, the transparent characteristics of the antenna described in the present invention ensure that it will not obstruct the driver's line of sight and avoid potential safety hazards during driving. The antenna can be used for robots and drones with flexibility and transparency, and the antenna described in this application can also be used for wearable devices.

[0059] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A polarization adjustable dual-band transparent flexible antenna, characterized in that: The antenna is made of a flexible conductive material and comprises an antenna ground (3) and two circular patches (5). An annular gap (6) is provided between the circular patch (5) and the antenna ground (3). A T-shaped feeder (4) and a one-to-two power splitter (8) are provided on one side of the circular patch (5). A switching diode is respectively connected between the two T-shaped feeders (4) and the one-to-two power splitter (8); a switching diode is respectively connected between the antenna ground (3) and the two ends of the one-to-two power splitter (8); and a feeding branch of the one-to-two power splitter (8) is connected to a coaxial connector (1).

2. The polarization-adjustable dual-band transparent flexible antenna according to claim 1, characterized in that: The center distance of the circular patch (5) is greater than the diameter of the circular patch (5).

3. The polarization-adjustable dual-band transparent flexible antenna according to claim 1, characterized in that: The switch diode comprises a first switch diode (21), a second switch diode (22), a third switch diode (71), and a fourth switch diode (72); the first switch diode (21) and the third switch diode (71) are symmetrically arranged, the second switch diode (22) and the fourth switch diode (72) are symmetrically arranged, the positive electrodes of the first switch diode (21) and the second switch diode (22) are connected to a one-to-two power distribution line (8), the negative electrode of the first switch diode (21) is connected to an antenna ground (3), and the negative electrode of the second switch diode (22) is connected to a T-type feeder (4).

4. The polarization-adjustable dual-band transparent flexible antenna according to claim 3, characterized in that: Working condition 1: when the first switch diode (21) and the third switch diode (71) are disconnected and the second switch diode (22) and the fourth switch diode (72) are connected, the current is coupled and fed to the two circular patches (5) through the one-to-two power splitter (8); the working frequency is 2.4 GHz to 6.5 GHz, and at the same time, far-field radiation with linear polarization in the y direction is formed in this frequency band; Working condition 2: when the first switch diode (21) is connected and the second switch diode (22), the third switch diode (71) and the fourth switch diode (72) are disconnected, the current feeds the two circular patches (5) via the one-to-two power splitter (8); the device operates at 2.5 GHz and 5.8 GHz, and simultaneously forms x-direction linear polarization far-field radiation at 2.5 GHz and forms left-hand circular polarization radiation at 5.8 GHz; Working condition three: when the third switch diode (71) is connected and the first switch diode (21), the second switch diode (22) and the fourth switch diode (72) are disconnected, the current feeds the two circular patches (5) through the one-to-two power distribution line (8), operates at 2.5 GHz and 5.8 GHz, and simultaneously forms x-direction linear polarization far-field radiation at 2.5 GHz and right-hand circular polarization radiation at 5.8 GHz.

5. The polarization-adjustable dual-band transparent flexible antenna according to claim 1, characterized in that: The longitudinal section of the T-shaped feeder (4) is connected to the one-to-two power splitter (8), the transverse section of the T-shaped feeder (4) is coupled to the circular patch (5), and the transverse section of the T-shaped feeder (4) is arc-shaped.

6. The polarization-adjustable dual-band transparent flexible antenna according to claim 1, characterized in that: It is made by etching process, laser engraving process or mask deposition process.

7. The polarization-adjustable dual-band transparent flexible antenna according to claim 1, characterized in that: PET polyester is used as the substrate, and the flexible conductive material is ITO indium tin oxide conductive flexible film, the square resistance does not exceed 6Ω, and the transmittance is not less than 87%.

8. The polarization-adjustable dual-band transparent flexible antenna according to claim 1, characterized in that: The one-to-two power distribution line (8) and the antenna ground (3) are made of the same material and formed in the same manner, and there is a gap between the one-to-two power distribution line (8) and the antenna ground (3).

9. The polarization-adjustable dual-band transparent flexible antenna according to claim 1, characterized in that: The two circular patches (5) and the T-shaped feeder (4) are arranged symmetrically about the perpendicular midline of the line connecting the centers of the circular patches.

10. A wireless communication device, characterized in that: A polarization-adjustable dual-frequency transparent flexible antenna as described in any one of claims 1 to 9 is adopted.

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