Planar antenna and terminal

Abstract

The invention relates to the technical field of antennas, and discloses a planar antenna and a terminal. The planar antenna comprises a radiator, at least two graphene assemblies and an adjusting device. Wherein the radiator is located in a first plane, the radiator feeds in an electric signal through a feeding point located at a first position so as to generate a first current along a first direction, and the first direction is parallel to the first plane. In the second direction, the radiator comprises a first radiation edge and a second radiation edge which are located on the two sides of the feeding point, and the second direction is parallel to the first plane and perpendicular to the first direction. The two graphene components are respectively connected with the radiator in an insulating manner, the orthographic projection of one of the two graphene components in the first plane is at least partially overlapped with the first radiation edge, and the orthographic projection of the other graphene component in the first plane is at least partially overlapped with the second radiation edge. The adjusting device is connected with the two graphene assemblies and used for adjusting the square resistance values of the two graphene assemblies. The planar antenna can realize continuous regulation and control of the polarization state.

Description

Technical Field

[0001] The present application relates to the field of antenna technology, and in particular to a planar antenna and a terminal. Background Art

[0002] With the development of satellite communication technology and backscatter communication technology, multi-polarization reconfigurable antennas are widely used in terminals such as vehicle-mounted navigation equipment and smart home devices. At present, in highly integrated and miniaturized terminals, multi-polarization reconfigurable antennas can adjust multiple polarization characteristics through a radiator. Multi-polarization reconfigurable antennas reconstruct the polarization state of antenna radiation waves and eliminate the effects of signal fading caused by multipath effects, which effectively solves problems such as polarization mismatch in wireless communications, thereby improving the system's anti-interference ability in complex and changing environments.

[0003] However, the current multi-polarization reconfigurable antenna can only realize discrete changes in several typical polarization states, such as linear polarization, left hand circularly polarization (LHCP) or right hand circularly polarization (RHCP), with poor adjustment effect and limited scope of application. Summary of the invention

[0004] In order to solve the above technical problems, the present application provides a planar antenna and a terminal. The present application is introduced from multiple aspects below, and the implementation methods and beneficial effects of the following multiple aspects can be referenced to each other.

[0005] In a first aspect, the present application provides a planar antenna. Specifically, the planar antenna includes a radiator, at least two graphene components and an adjustment device. The radiator is located in a first plane, and the radiator is fed with an electrical signal through a feeding point located at a first position so as to generate a first current along a first direction, and the first direction is parallel to the first plane. Along the second direction, the radiator includes a first radiating edge and a second radiating edge located on both sides of the feeding point, and the second direction is parallel to the first plane and perpendicular to the first direction. The two graphene components are respectively insulated and connected to the radiator, and the orthographic projection of one of the two graphene components in the first plane at least partially overlaps with the first radiating edge, and the orthographic projection of the other graphene component in the first plane at least partially overlaps with the second radiating edge. The adjustment device is connected to the two graphene components for adjusting the square resistance values ​​of the two graphene components.

[0006] In the embodiment of the present application, graphene components with different square resistance values ​​can cause the potential to change in the second direction, thereby generating a current along the second direction. The current along the second direction interacts with the first current along the first direction, which can change the distribution characteristics of the current on the radiator, thereby changing the polarization state of the planar antenna. Therefore, by gradually adjusting the square resistance values ​​of the two graphene components, continuous regulation of right-handed elliptical polarization, linear polarization, and left-handed circular elliptical polarization can be achieved.

[0007] In a possible implementation of the first aspect, along the first direction, the ratio between the distance between the two graphene components and the size of the radiator is 0 to 0.5, for example, 0, 0.1, 0.2, etc. Thus, the planar antenna can achieve continuous regulation between right-hand circular polarization, right-hand elliptical polarization, linear polarization, left-hand elliptical polarization and left-hand circular polarization, further expanding the scope of application.

[0008] In a possible implementation of the first aspect, along the second direction, the ratio between the distance between the two graphene components and the size of the radiator is 0.5 to 1, for example, 0.5, 0.6, 0.7, etc., thereby further improving the continuous control effect between right-hand circular polarization, right-hand elliptical polarization, linear polarization, left-hand elliptical polarization and left-hand circular polarization of the planar antenna.

[0009] In a possible implementation of the first aspect, the adjustment device is used to transmit a first voltage to one of the two graphene components and transmit a second voltage to the other graphene component, and the adjustment device can control the magnitude of the first voltage and the magnitude of the second voltage to adjust the square resistance of the two graphene components, thereby effectively improving the effect of continuously adjustable polarization state of the planar antenna.

[0010] In a possible implementation of the first aspect above, the regulating device includes a voltage controller and a DC bias line, and the voltage controller is connected to the two graphene components through the DC bias line.

[0011] According to the implementation mode of the present application, the regulating device can realize the regulation of the square resistance of the two graphene components through the voltage controller and the DC bias line. The control method is simple and the wiring complexity is small.

[0012] In a possible implementation of the first aspect, the number of graphene components is four, the orthographic projections of the four graphene components in the first plane do not overlap with each other, and the four graphene components are respectively the first graphene component, the second graphene component, the third graphene component and the fourth graphene component. Among them, the orthographic projections of the first graphene component and the third graphene component in the first plane overlap at least partially with the first radiation edge, the orthographic projections of the second graphene component and the fourth graphene component in the first plane overlap at least partially with the second radiation edge, and, along the first direction, the first graphene component is farther away from the fourth graphene component than the third graphene component, and the second graphene component is closer to the first graphene component than the fourth graphene component. The regulating device is used to deliver a first voltage to the first graphene component and the fourth graphene component, and deliver a second voltage to the second graphene component and the third graphene component.

[0013] The four graphene components can further improve the current distribution characteristics on the radiator, thereby further enhancing the effect of continuous control of the polarization state of the planar antenna.

[0014] In a possible implementation of the first aspect, along the first direction, the ratio of the distance between the first graphene component and the second graphene component to the size of the radiator is 0-0.5, for example, 0, 0.1, 0.2, etc.; the ratio of the distance between the third graphene component and the fourth graphene component to the size of the radiator is 0-0.5, for example, 0, 0.1, 0.2, etc. Also, along the second direction, the ratio of the distance between the first graphene component and the second graphene component to the size of the radiator is 0.5-1, for example, 0.5, 0.6, 0.7, etc.; the ratio of the third graphene component and the fourth graphene component to the size of the radiator is 0.5-1, for example, 0.5, 0.6, 0.7, etc.

[0015] Based on this, the above-mentioned planar antenna can achieve continuous control between right-hand circular polarization, right-hand elliptical polarization, linear polarization, left-hand elliptical polarization and left-hand circular polarization, further improving the effect of continuous control of the polarization state and expanding the scope of application.

[0016] In a possible implementation of the first aspect, the square resistance of the graphene component varies in the range of 1 ohm / sq to 1 Mohm / sq, thereby further improving the control effect of the polarization state of the planar antenna.

[0017] In a possible implementation of the first aspect above, the graphene component includes a layer of graphene, or includes multiple layers of graphene stacked along a third direction, and a separator paper is provided between two adjacent layers of graphene, and the third direction is perpendicular to the first plane.

[0018] According to the implementation mode of the present application, the diaphragm paper is usually soaked in ionic liquid to further expand the range of variation of the square resistance of the graphene component, thereby improving the control effect of the polarization state of the planar antenna.

[0019] In a possible implementation of the first aspect above, the planar antenna includes a first dielectric plate and a ground plane, and the radiator, the first dielectric plate and the ground plane are stacked in sequence along a third direction, and the third direction is perpendicular to the first plane; the graphene component is located on the side of the radiator facing away from the first dielectric plate, and an insulating layer is provided between the graphene component and the radiator, or the graphene component is located between the first dielectric plate and the ground plane, and the graphene component and the ground plane are insulated and connected.

[0020] In a possible implementation of the first aspect, a second dielectric plate is provided between the graphene assembly and the ground plate, so that the graphene assembly and the ground plate can be insulated from each other and avoid mutual interference between the graphene assembly and the ground plate.

[0021] In a possible implementation of the first aspect above, a shape of an orthographic projection of the graphene component in the first plane includes any one or more of a rectangle, a circle, a sector or a polygon.

[0022] In a possible implementation of the first aspect, the shape of the radiator includes any one or more of a rectangle, a circle, or a polygon.

[0023] In a possible implementation of the first aspect above, the planar antenna is a patch antenna or a planar inverted-F antenna.

[0024] The second aspect of the present application provides a planar antenna. Specifically, the planar antenna includes a radiator, a graphene component and an adjustment device. The radiator is located in a first plane, and the radiator is fed with an electrical signal through a feeding point located at a first position so as to generate a first current along a first direction, and the first direction is parallel to the first plane. Along the second direction, the radiator includes a first radiating edge and a second radiating edge located on both sides of the feeding point, and the second direction is parallel to the first plane and perpendicular to the first direction. The graphene component is insulated from the radiator, and the orthographic projection of the graphene component in the first plane at least partially overlaps with the first radiating edge or the second radiating edge. The adjustment device is connected to the graphene component for adjusting the square resistance value of the graphene component.

[0025] In the embodiment of the present application, graphene components with different square resistance values ​​can cause the potential to change in the second direction, thereby generating a current along the second direction. The current along the second direction interacts with the first current along the first direction, which can change the distribution characteristics of the current on the radiator, thereby changing the polarization state of the planar antenna. Therefore, by gradually adjusting the square resistance value of the graphene component, it is possible to achieve continuous regulation of linear polarization, left-handed elliptical polarization, and left-handed circular polarization, or to achieve continuous regulation of linear polarization, right-handed elliptical polarization, and left-handed elliptical polarization.

[0026] The third aspect of the present application provides a terminal, which includes a housing and any one of the planar antennas described in the first aspect, a possible implementation of the first aspect, and the second aspect, wherein the planar antenna is disposed on the housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figures 1A to 1D A schematic diagram showing the electric field intensity vector of an electromagnetic wave propagating along the positive Z direction in an embodiment of the present application is shown;

[0028] Figure 2A An exemplary application scenario 1 of the planar antenna in an embodiment of the present application is shown;

[0029] Figure 2B The second exemplary application scenario of the planar antenna in the embodiment of the present application is shown;

[0030] Figure 3A Shows a schematic diagram of the structure of a planar antenna in some embodiments;

[0031] Figure 3B A schematic diagram of the structure of a feeding network in a planar antenna in some embodiments is shown;

[0032] FIG. 4A to FIG. 4D Shows schematic structural diagrams of several planar antennas in other embodiments;

[0033] Figure 5A and Figure 5B The schematic diagram of the structure of the planar antenna in the embodiment of the present application is shown, wherein: Figure 5A is the top view of the planar antenna. Figure 5B This is an exploded diagram of a planar antenna;

[0034] FIG. 6A to FIG. 6C An exemplary distribution diagram of the current on the radiator of the planar antenna in different polarization states in an embodiment of the present application is shown;

[0035] Fig. 7A according to Figure 5A A schematic diagram of the axial ratio of the planar antenna in the embodiment of the present application when working in circular polarization and linear polarization states is shown;

[0036] Figure 7B according to Figure 5A A schematic diagram of reflection coefficients when the planar antenna in an embodiment of the present application works in circular polarization and linear polarization states is shown;

[0037] Figure 7C according to Figure 5A A schematic diagram showing the radiation efficiency of the planar antenna in the embodiment of the present application when operating in circular polarization and linear polarization states;

[0038] Fig. 8A and Figure 8B An exemplary arrangement of four graphene components in an embodiment of the present application is shown, wherein: Fig. 8A is a top view of the planar antenna 10, Figure 8B This is an exploded diagram of a planar antenna;

[0039] 9A to 9C An exemplary distribution diagram of the current on the radiator of the planar antenna in different polarization states in an embodiment of the present application is shown;

[0040] Fig. 10A according to Fig. 8A and Figure 8B A schematic diagram of the axial ratio of the planar antenna in the embodiment of the present application when working in left-hand circular polarization, right-hand circular polarization and linear polarization states is shown;

[0041] Fig. 10B according to Fig. 8A and Figure 8B A schematic diagram of reflection coefficients when the planar antenna in an embodiment of the present application works in left-hand circular polarization, right-hand circular polarization and linear polarization states is shown;

[0042] Fig. 10C according to Fig. 8A and Figure 8B A schematic diagram showing the radiation efficiency of the planar antenna in the embodiment of the present application when operating in left-hand circular polarization, right-hand circular polarization and linear polarization states;

[0043] Fig. 10D according to Fig. 8A and Figure 8B A schematic diagram showing a continuous change in the axial ratio of a planar antenna in an embodiment of the present application is shown;

[0044] Fig.11A according to Figure 3A and Figure 3B A schematic diagram of the axial ratio of a planar antenna in some embodiments is shown;

[0045] Fig. 11B according to Figure 4C Schematic diagrams of axial ratios of planar antennas in other embodiments are shown;

[0046] Fig. 12A according to Fig. 8Aand Figure 8B A schematic diagram of the axial ratio of the planar antenna in the embodiment of the present application when operating in circular polarization is shown;

[0047] Fig. 12B according to Fig. 8A and Figure 8B A schematic diagram of reflection coefficient when the planar antenna in an embodiment of the present application works in circular polarization is shown;

[0048] Fig. 12C according to Fig. 8A and Figure 8B A schematic diagram showing the radiation efficiency of the planar antenna in the embodiment of the present application when working in circular polarization is shown;

[0049] Fig.13A An exemplary layout mode 1 of the graphene assembly in the embodiment of the present application is shown;

[0050] Fig. 13B The second exemplary layout of the graphene assembly in the embodiment of the present application is shown;

[0051] Fig.14A according to Fig. 8A , Fig.13A and Fig. 13B A schematic diagram of the axial ratio of the planar antenna in different graphene component layouts in an embodiment of the present application is shown;

[0052] Fig. 14B according to Fig. 8A , Fig.13A and Fig. 13B A schematic diagram of the reflection coefficient of the planar antenna in different graphene component layouts in an embodiment of the present application is shown;

[0053] Fig. 14C according to Fig. 8A , Fig.11A and Fig. 11B A schematic diagram showing the radiation efficiency of the planar antenna in different graphene component layouts in an embodiment of the present application is shown;

[0054] Fig.15 shows exemplary configurations of graphene components in other embodiments of the present application;

[0055] Fig.16 A schematic structural diagram of a planar antenna including a graphene component in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0056] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0057] It should be understood that the "multiple" mentioned in this application refers to two or more. In the description of this application, unless otherwise specified, " / " means or, for example, A / B can mean A or B; "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in order to facilitate the clear description of the technical solution of this application, the words "first" and "second" are used to distinguish between the same items or similar items with basically the same functions and effects. Those skilled in the art can understand that the words "first" and "second" do not limit the quantity and execution order, and the words "first" and "second" do not limit them to be different.

[0058] To facilitate understanding of the technical solution of the present application, some concepts or terms involved in the present application are first explained.

[0059] Polarization of antenna: The polarization of an antenna is defined by the spatial orientation of the electric field intensity vector of the electromagnetic wave radiated by the antenna in the direction of maximum radiation. It is a parameter that describes the spatial orientation of the electromagnetic wave vector radiated by the antenna. Since the electric field and magnetic field of electromagnetic waves have a constant relationship, the spatial orientation of the electric field intensity vector is generally used as the polarization direction of the electromagnetic wave radiated by the antenna. The polarization of antennas is divided into linear polarization, circular polarization and elliptical polarization. Linear polarization is further divided into horizontal polarization and vertical polarization. (Elliptical) circular polarization is further divided into left-hand (elliptical) circular polarization and right-hand (elliptical) circular polarization.

[0060] Specifically, Figures 1A to 1D FIG. 1 is a schematic diagram showing the electric field intensity vector of an electromagnetic wave propagating along the positive Z direction in an embodiment of the present application. Figures 1A to 1D , in three-dimensional space, the electric field intensity vector of the electromagnetic wave propagating along the positive Z direction is Includes two components and and The instantaneous value in the time domain is shown as follows:

[0061]

[0062]

[0063] Among them, E Xm for The amplitude of the electromagnetic wave, w is the frequency of the electromagnetic wave, k is the wave number, for The phase, E Ym for The amplitude of for According to the phase. and Due to the relative relationship between amplitude and phase, electromagnetic waves present different polarization states.

[0064] For example, refer to Figure 1B ,when and When the phase difference is an integer multiple of π, the resultant electric field vector The orthographic projection in the XOY plane is a straight line, and the electromagnetic wave is a linearly polarized wave. Accordingly, the antenna works in a linearly polarized state. It can be understood that the XOY plane is a plane perpendicular to the propagation direction of the electromagnetic wave (i.e., the positive Z direction). If the ground is used as the reference plane, the linearly polarized wave can be divided into vertically polarized waves and horizontally polarized waves. Specifically, when the electric field vector When the electromagnetic wave is perpendicular to the ground, it is a vertically polarized wave; when the electric field vector When the electromagnetic wave is parallel to the ground, it is a horizontally polarized wave.

[0065] For example, refer to Figure 1C ,when and When the phase difference is 90° and the amplitude is equal, the resultant electric field vector The orthographic projection in the XOY plane is a circle, and the electromagnetic wave is a circularly polarized wave. Accordingly, the antenna works in a circularly polarized state. In which, looking along the propagation direction of the electromagnetic wave (i.e., the positive Z direction), the synthesized electric field vector The projection in the XOY plane rotates clockwise, and the electromagnetic wave is a right-hand circularly polarized wave; conversely, looking along the propagation direction of the electromagnetic wave (i.e., the positive Z direction), the synthetic electric field vector The projection in the XOY plane rotates counterclockwise, and the electromagnetic wave is a left-hand circularly polarized wave.

[0066] For example, refer to Figure 1D ,when and When the phase difference and amplitude are other cases, the resultant electric field vector The orthographic projection in the XOY plane is an ellipse, and the electromagnetic wave is an elliptically polarized wave. Accordingly, the antenna works in an elliptically polarized state. Similarly, looking along the propagation direction of the electromagnetic wave (i.e., the positive Z direction), the synthesized electric field vector The projection in the XOY plane rotates clockwise, and the electromagnetic wave is a right-handed elliptically polarized wave; conversely, looking along the propagation direction of the electromagnetic wave (i.e., the positive Z direction), the synthesized electric field vector The projection in the XOY plane rotates counterclockwise, and the electromagnetic wave is a left-handed elliptically polarized wave.

[0067] The ratio between the major axis a and the minor axis b of an elliptically polarized wave is the axial ratio. Generally speaking, when the axial ratio is less than 3dB (for example, the axial ratio is 0dB or 1dB), the electromagnetic wave can be approximately regarded as a circularly polarized wave; when the axial ratio is between 3dB and 10dB (for example, the axial ratio is 3dB or 4dB), the electromagnetic wave is an elliptically polarized wave; when the axial ratio is greater than 10dB (for example, the axial ratio is 30dB or 40dB), the electromagnetic wave can be approximately regarded as a linearly polarized wave.

[0068] The implementation methods of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0069] The embodiments of the present application are used to provide a planar antenna and a terminal including the planar antenna. The terminal provided in the present application may include but is not limited to a vehicle-mounted terminal, a smart home terminal (e.g., a smart TV, a smart switch, a smart speaker, etc.), a mobile phone, a tablet computer, a laptop computer, a wireless headset (e.g., a true wireless stereo (TWS) headset, etc.), a wearable device (e.g., a smart watch, a smart bracelet, a smart helmet, a smart glasses, smart jewelry, etc.), an augmented reality (AR) / virtual reality (VR) device, and any terminal with a wireless communication function, and the present application does not specifically limit this.

[0070] For example, the terminal may be a ceiling speaker, and the planar antenna may be applied to the ceiling speaker. Figure 2A FIG. 1 shows an exemplary application scenario 1 of the planar antenna 10 in an embodiment of the present application. Figure 2A For example, the planar antenna 10 can be integrated into a reader 20 and installed at the bottom of a housing 11 of the ceiling speaker 1. The planar antenna 10 is used to realize communication between the reader 20 and a passive tag 30, thereby realizing the function of sensing indoor objects.

[0071] Specifically, after the passive tag 20 enters the magnetic field generated by the reader 30, the reader 30 can activate the passive tag 20 through the radio frequency excitation signal emitted by the planar antenna 10. The passive tag 20 can modulate the object identification information stored in itself onto the radio frequency signal through the backscatter communication technology to send the reflected signal to the reader 30 through the planar antenna 10. After the reader 30 demodulates the received reflected signal, it is sent to the central information system for relevant data processing, thereby realizing the recognition and perception of the indoor objects by the ceiling speaker 1, and meeting the intelligent requirements of the ceiling speaker 1.

[0072] Exemplarily, the passive tag 20 usually works in a circular polarization state, that is, the electromagnetic wave emitted by the passive tag 20 is a circularly polarized wave (eg, a left-hand circularly polarized wave or a right-hand circularly polarized wave).

[0073] In order to communicate normally with the passive tag 20, in some cases, the planar antenna 10 is a linearly polarized antenna. However, the polarization state of the linearly polarized antenna and the polarization state of the passive tag 20 are not completely matched, so there will be a 3dB loss in the signal transmission process, and the communication distance between the planar antenna 10 and the passive tag 20 is limited.

[0074] For another example, the terminal may be a vehicle, and the planar antenna may be used in the vehicle. Figure 2B FIG. 2 shows an exemplary application scenario 2 of the planar antenna 10 in an embodiment of the present application. Figure 2B The vehicle 2 includes a planar antenna 10 integrated on a housing 40 on the roof. The planar antenna 10 can be used to implement communication between the vehicle 2 and the satellite 3 to determine the precise location of the vehicle 1 and provide a navigation function. The satellite 2 can include, but is not limited to, any one or more of a global navigation satellite system (GNSS) satellite, a Beidou navigation satellite system (BDS) satellite, or a Tiantong satellite.

[0075] Among them, the polarization states of different satellite communication systems are different. For example, the L1 band and L5 band of the global satellite navigation system are both right-hand circular polarization. The Beidou satellite navigation system is a dual-frequency dual-polarization combination (that is, the uplink band is left-hand circular polarization, and the downlink band is right-hand circular polarization). The uplink and downlink bands of the Tiantong satellite are both left-hand circular polarization.

[0076] In order to realize the communication between the vehicle 2 and the satellite 3, in some cases, a plurality of planar antennas with different polarization states may be arranged on the vehicle 2. However, the plurality of planar antennas 10 will occupy a large layout space, which is not conducive to the high integration and miniaturization development of the vehicle 2.

[0077] In order to avoid the above-mentioned signal transmission loss and the problem of excessive space occupation, in other cases, the planar antenna 10 can be a polarization reconfigurable antenna.

[0078] For example, the feeding structure can be switched by a switch or a switch-like device to stimulate different current modes on the antenna radiator, thereby enabling the antenna to produce different polarization states and realize polarization reconfiguration of the antenna.

[0079] Figure 3A Schematic diagrams of the structures of the planar antenna 10a in some embodiments are shown. Figure 3BFIG. 2 shows a schematic diagram of the structure of a feeding network 200a in a planar antenna 10a in some embodiments. Figure 3A and Figure 3B The planar antenna 10a includes a radiator 100a and a feeding network 200a connected to each other. The feeding network 200a includes six microstrip lines 210a and eight positive-intrinsic negative diodes (PINs) 220a. By changing the on-off state of the eight diodes 220a, different feeding modes can be realized to stimulate currents with different directions and phase differences, thereby realizing the polarization state switching of left-hand circular polarization, right-hand circular polarization, -45° linear polarization and +45° linear polarization.

[0080] However, in the above-mentioned planar antenna 10a, the on-off combinations of the eight diodes 220a are limited, and only the discrete transformation of the above-mentioned typical polarization states can be realized, and the application scenarios are limited, and the polarization matching requirements in various application scenarios cannot be met.

[0081] For another example, the current distribution characteristics on the radiator can be changed by changing the shape of the radiator, so that the planar antenna can produce different polarization states, thereby realizing the polarization reconfiguration of the antenna.

[0082] FIG. 4A to FIG. 4D Schematic diagrams of the structures of several planar antennas 10b in other embodiments are shown. Figure 4A As shown, gaps G1 can be respectively opened at the four corners of the radiator 100b of the planar antenna 10b, and switches 200b can be set. By controlling the on and off of the switches 200b, the shape of the radiator 100b can be changed, thereby achieving different polarization effects. Figure 4B As shown, gaps G1 can also be opened at the four corners of the radiator 100b of the planar antenna 10b, and diodes 300b can be set. The shape of the radiator 100b can be changed by controlling the on and off of the diodes 300b, thereby achieving different polarization effects. Figure 4C As shown, gaps G1 can be opened at two corners of the planar antenna 10b, and diodes 300b can be set. The shape of the radiator 100b can be changed by controlling the on and off of the diodes 300b, thereby achieving different polarization effects. Figure 4D As shown, the four corners of the radiator 100b can also be cut off and replaced with graphene 400b. Graphene 400b is a material with variable conductivity. By adjusting the conductive and insulating properties of graphene 400b, the shape of the radiator 100b can be changed, thereby achieving different polarization effects.

[0083] However, in the above-mentioned planar antenna 10b, whether controlling the on and off of the switch 200b or the diode 300b, or adjusting the conductivity of the graphene 400b, the radiator 100b can only achieve a few limited shape changes, so the planar antenna 10b can still only achieve discrete transformations of a few typical polarization states.

[0084] In order to solve the problem of discontinuous polarization state transformation mentioned above, the present application provides a planar antenna that can achieve continuous control of right-handed elliptical polarization, linear polarization, and left-handed elliptical polarization states, which will be described in detail below with reference to the accompanying drawings.

[0085] It can be understood that the planar antenna provided in the present application may include but is not limited to any one of a patch antenna or a planar inverted F-shaped antenna (PIFA). For ease of description, the planar antenna is a patch antenna as an example for introduction below.

[0086] Figure 5A and Figure 5B The schematic diagram of the structure of the planar antenna 10 in the embodiment of the present application is shown, wherein: Figure 5A is a top view of the planar antenna 10, Figure 5B is an exploded view of the planar antenna 10. Figure 5A and Figure 5B The planar antenna 10 includes a radiator 100 , at least two graphene components 200 and an adjustment device 300 .

[0087] The radiator 100 is located in the first plane S0. The radiator 100 may include a feeding point P1 located at a first position. The feeding point P1 is a feeding connection point between the feed line 400 and the radiator 100. For example, when the planar antenna 10 is fed by side feeding, the feed line 400 may be connected to the midpoint of the side 101 of the radiator 100, and the feeding point P1 is located at the midpoint of the side 101 of the radiator 100 (i.e., the first position). When the feed line 400 feeds the radiator 100 via the feeding point P1, a first current I1 may be generated on the radiator 100. The current direction of the first current I1 is the A direction (as the first direction). The A direction is parallel to the first plane S0.

[0088] It should be noted that the first current I1 distributed on the radiator 100 may include multiple current directions, and there may be slight differences between the multiple current directions, and they are not strictly the same, but there is a direction that can roughly represent the overall current distribution. In this embodiment, the current direction of the first current I1 (i.e., direction A) refers to the approximate current direction of the first current I1.

[0089] Along the B direction (as the second direction), the radiator 100 further includes a first radiating edge 110 and a second radiating edge 120 located at opposite sides of the feeding point P1. The B direction is parallel to the first surface S0 and perpendicular to the A direction.

[0090] The graphene component 200 is insulated from the radiator 100 , that is, the radiator 100 and the graphene component 200 are insulated from each other, thereby preventing the graphene component 200 from interfering with the radiation of the radiator 100 .

[0091] The two graphene components 200 may be a first graphene component 200a and a second graphene component 200b, wherein the orthographic projection S1 of the first graphene component 200a in the first plane S0 at least partially overlaps with the first radiation edge 110, and the orthographic projection S2 of the second graphene component 200b in the first plane S0 at least partially overlaps with the second radiation edge 120.

[0092] The adjustment device 300 is connected to the first graphene component 200a and the second graphene component 200b to adjust the square resistance of the first graphene component 200a and the square resistance of the second graphene component 200b. Graphene components 200 with different square resistances absorb energy in the A direction (i.e., energy fed by the feeder 400 to the radiator 200) to different degrees, thus causing the potential to change in the B direction, thereby generating a current in the B direction (e.g., the second current I2 described below). The current in the B direction interacts with the first current I1 in the A direction, which can change the distribution characteristics of the current on the radiator 100, thereby changing the polarization state of the planar antenna 10.

[0093] FIG. 6A to FIG. 6C FIG. 1 shows an exemplary distribution diagram of the current on the radiator 100 of the planar antenna 10 in different polarization states in the embodiment of the present application. FIG. 6A to FIG. 6C , the radiator 100 is rectangular, and the first radiating side 110 and the second radiating side 120 are two opposite sides of the rectangular radiator 100 along the direction B. The orthographic projection S1 of the first graphene component 200a in the first plane S0 can be located at the lower right corner of the radiator 100, and the orthographic projection S2 of the second graphene component 200b in the first plane S0 can be located at the lower left corner of the radiator 100.

[0094] like Fig. 6A As shown, when the square resistance of the first graphene component 200a is the same as the square resistance of the second graphene component 200b, there is no potential difference in the B direction, and the current distributed on the radiator 200 is the first current I1 along the A direction. At this time, the electromagnetic wave radiated by the radiator 200 is a linearly polarized wave. The planar antenna 10 works in a linearly polarized state.

[0095] like Figure 6BAs shown, when the square resistance of the first graphene component 200a is greater than the square resistance of the second graphene component 200b, the energy absorbed by the first graphene component 200a in the A direction is greater than the energy absorbed by the second graphene component 200b in the A direction. Therefore, a second current I2 can be generated on the radiator 100. The second current I2 flows from the first radiation edge 110 to the second radiation edge 120 along the B direction. At this time, within a phase period, the current vector synthesized by the superposition of the first current I1 and the second current I2 rotates in a clockwise direction. Therefore, the electromagnetic wave radiated by the radiator 200 can be a left-handed elliptically polarized wave. The planar antenna 10 can operate in a left-handed elliptically polarized state.

[0096] like Figure 6C As shown, when the square resistance of the first graphene component 200a is less than the square resistance of the second graphene component 200b, the energy absorbed by the first graphene component 200a in the A direction is less than the energy absorbed by the second graphene component 200b in the A direction. Therefore, a second current I2 can be generated on the radiator 100. The second current I2 flows from the second radiation edge 120 to the first radiation edge 110 along the B direction. At this time, within a phase cycle, the current vector synthesized by the superposition of the first current I1 and the second current I2 rotates counterclockwise. Therefore, the electromagnetic wave radiated by the radiator 200 can be a right-handed elliptically polarized wave. The planar antenna 10 can operate in a right-handed elliptically polarized state.

[0097] It can be understood that as the difference between the square resistance of the first graphene component 200a and the square resistance of the second graphene component 200b gradually increases from a negative value to a positive value, the polarization state of the planar antenna 10 will continuously change from right-handed elliptical polarization, linear polarization to elliptical polarization, thereby realizing the function of continuous reconstruction of the polarization of the planar antenna 10.

[0098] The above-mentioned planar antenna 10 can achieve continuous control of right-handed elliptical polarization, linear polarization, and left-handed circular elliptical polarization by adjusting the square resistance of the first graphene component 200a and the square resistance of the second graphene component 200b, and has good working performance.

[0099] Secondly, the first graphene component 200a and the second graphene component 200b are disposed near the radiator 100, and no additional slits or corner cuts are required on the radiator 100, which will not damage the structure of the radiator 100. For example, FIG. 4A to FIG. 4D The structure of the radiator 100b of the planar antenna 10b shown will be destroyed, and the original structure is greatly modified, which affects the working stability of the planar antenna 10b. In the present application, the polarization continuous reconstruction of the planar antenna 10 can be achieved by changing the square resistance value of the first graphene component 200a and the square resistance value of the second graphene component 200b, and the structure of the radiator 100 will not be changed.

[0100] In addition, the first graphene component 200a and the second graphene component 200b do not directly participate in radiation and do not introduce additional losses, so while achieving continuous polarization reconstruction, it also ensures that the planar antenna 10 can have good working performance. For example, Figure 3A and Figure 3B In the planar antenna 10a shown, the feed network 200a is formed by cascading six microstrip lines 210a and eight diodes 220a. This will result in a large loss in the feed network 200a, thereby affecting the radiation efficiency of the planar antenna 10a. For example, FIG. 4A to FIG. 4D In the planar antenna 10b shown, the switch 200b or the diode 300b may easily affect the radiation efficiency of the planar antenna 10b. The graphene 400b directly used as a part of the radiator 100b may also cause losses, thereby affecting the radiation efficiency of the planar antenna 10b.

[0101] Finally, the above-mentioned planar antenna 10 has a simple structure, a low profile, is easy to integrate, has a low manufacturing cost, and has good reliability. Figure 3A and Figure 3B The overall size of the feeding network 200 of the planar antenna 10a shown is relatively large and the design is complex, so the planar antenna 10a is difficult to be integrated into a terminal with limited space. FIG. 4A to FIG. 4C In the planar antenna 10b shown, control devices such as the switch 200b or the diode 300b need to be connected across the gap G1, and the overall structure is relatively complex, which increases the manufacturing cost and has poor structural reliability. In the present application, the first graphene component 200a and the second graphene component 200b are arranged close to the radiator 100, which will not occupy too much thickness space of the planar antenna 10. The overall structure of the planar antenna 10 is relatively compact and simple, which is conducive to the high integration and miniaturization of the terminal, with low cost and good reliability.

[0102] Continue reading Figure 5A In some embodiments of the present application, along the A direction, the ratio between the distance between the first graphene component 200a and the second graphene component 200b and the size of the radiator 100 can be 0 to 0.5, for example, 0, 0.1, 0.2, etc. In this way, by adjusting the square resistance of the first graphene component 200a and the square resistance of the second graphene component 200b, a larger second current (not shown) can be generated. In this way, the planar antenna 10 can achieve continuous regulation between right-hand circular polarization, right-hand elliptical polarization, linear polarization, left-hand elliptical polarization and left-hand circular polarization, further expanding the scope of application.

[0103] In order to further improve the continuous control effect between the right-hand circular polarization, right-hand elliptical polarization, linear polarization, left-hand elliptical polarization and left-hand circular polarization of the planar antenna 10, along the B direction, the ratio of the distance between the first graphene component 200a and the second graphene component 200b to the size of the radiator 100 can be 0.5 to 1, for example, 0.5, 0.6, 0.7, etc.

[0104] To facilitate understanding of the polarization effect of the planar antenna 10 , the following describes the corresponding axial ratio, reflection coefficient, radiation efficiency, etc. when the planar antenna 10 works in circular polarization and linear polarization states.

[0105] For example, Fig. 7A according to Figure 5A A schematic diagram of the axial ratio of the planar antenna 10 in the embodiment of the present application when operating in circular polarization and linear polarization states is shown. Figure 7B according to Figure 5A A schematic diagram of reflection coefficients when the planar antenna 10 in the embodiment of the present application works in circular polarization and linear polarization states is shown. Figure 7C according to Figure 5A The schematic diagram of the radiation efficiency of the planar antenna 10 in the embodiment of the present application when it works in circular polarization and linear polarization states is shown. It should be noted that: FIG. 7A to FIG. 7C Shown are various parameters of the planar antenna 10 when the center frequency is 1.60 GHz.

[0106] refer to Fig. 7A When the planar antenna 10 works in a circular polarization state, the axial ratio can be less than 3 dB, for example, the minimum axial ratio is about 2 dB, and the circular polarization effect of the planar antenna 10 is good. When the planar antenna 10 works in a linear polarization state, the axial ratio can be greater than 60 dB, for example, the maximum axial ratio is about 70 dB, and the linear polarization effect of the planar antenna 10 is good.

[0107] refer to Figure 7B , the reflection coefficient curve of the planar antenna 10 working in the circular polarization state is close to the reflection coefficient curve of the planar antenna 10 working in the linear polarization state. Therefore, when the planar antenna 10 switches between the circular polarization state and the linear polarization state, its reflection coefficient will not fluctuate greatly, thereby effectively ensuring the working stability of the planar antenna 10 and improving the working performance of the planar antenna 10.

[0108] refer to Figure 7C Whether working in a circular polarization state or a linear polarization state, the planar antenna 10 can maintain good radiation efficiency and good working performance. For example, when the planar antenna 10 works in a circular polarization state, the radiation efficiency is approximately greater than 0.3. When the planar antenna 10 works in a linear polarization state, the radiation efficiency is approximately greater than 0.4.

[0109] In addition, the planar antenna 10 has the advantage of a stable radiation pattern during the continuous regulation of the polarization state, that is, the radiation direction of the planar antenna 10 does not change with the change of the polarization state, and the planar antenna 10 has good radiation stability.

[0110] The above-mentioned planar antenna 10, by rationally arranging the first graphene component 200a and the second graphene component 200b, can realize continuous regulation of multiple polarization states such as left-hand circular polarization, left-hand elliptical polarization, linear polarization, right-hand circular elliptical polarization, right-hand circular polarization and their intermediate states, meet the working requirements in various application scenarios, effectively improve the working performance and expand the scope of application. For example, when the above-mentioned planar antenna 10 is applied to Figure 2A When the planar antenna 1 is used in the ceiling speaker 1, it can be well matched with various polarization states of the passive tag 30. At the same time, the planar antenna 10 also has the advantages of stable radiation pattern and low profile, so it can effectively solve the problem of short communication distance between the reader 20 and the passive tag 30 due to polarization mismatch, and it is also easy to be integrated in the ceiling speaker 1. For another example, when the planar antenna 10 is applied to Figure 2B When in the vehicle 2 shown, the polarization states required by various satellite communication standards can be achieved without occupying too much layout space. At the same time, the planar antenna 10 also has the advantages of low profile and easy integration, which is conducive to achieving highly integrated and miniaturized development.

[0111] Continue reading Figure 5A In some embodiments of the present application, the adjustment device 300 can transmit a first voltage V1 to the first graphene component 200a and a second voltage V2 to the second graphene component 200b. By controlling the magnitude of the first voltage V1 and the second voltage V2, the square resistance of the first graphene component 200a and the square resistance of the second graphene component 200b can be adjusted, thereby achieving continuous adjustment of the polarization state of the planar antenna 10.

[0112] Exemplarily, the regulating device 300 may include a voltage controller 310 and a DC bias line 320. The voltage controller 310 is connected to the first graphene component 200a and the second graphene component 200b through the DC bias line 320, so as to be able to deliver a first voltage V1 to the first graphene component 200a and a second voltage V2 to the second graphene component 200b.

[0113] Combination Figure 5A and Fig. 7A When the first voltage V1 and the second voltage V2 are both 0V, the square resistance of the first graphene component 200a and the square resistance of the second graphene component 200b are both 3000 ohm / sq. At this time, the planar antenna 10 can work in a linear polarization state, and the axial ratio of the planar antenna 10 is about greater than 40 dB.

[0114] When the first voltage V1 is 0V and the second voltage V2 varies between 0 and 5V, the polarization state of the planar antenna 10 can be continuously changed between linear polarization, left-handed elliptical polarization and left-handed circular polarization. For example, when the first voltage V1 is 0V and the second voltage V2 is 5V, the square resistance of the first graphene component 200a is 3000ohm / sq, and the square resistance of the second graphene component 200b is 400ohm / sq. At this time, the planar antenna 10 can work in the left-handed circular polarization state, and the axial ratio of the planar antenna 10 is less than about 3dB.

[0115] Conversely, when the first voltage V1 varies between 0 and 5V and the second voltage is 0V, the polarization state of the planar antenna 10 can be continuously changed between linear polarization, right-hand elliptical polarization and right-hand circular polarization. For example, when the first voltage V1 is 5V and the second voltage V2 is 0V, the square resistance of the first graphene component 200a is 400ohm / sq, and the square resistance of the second graphene component 200b is 3000ohm / sq. At this time, the planar antenna 10 can work in the right-hand circular polarization state, and the axial ratio of the planar antenna 10 is less than about 3dB.

[0116] The adjusting device 300 can accurately adjust the square resistance of the first graphene component 200a and the square resistance of the second graphene component 200b through voltage, thereby effectively improving the effect of continuous adjustment of the polarization state of the planar antenna 10. In addition, the adjusting device 300 has a small routing complexity and a simple structure. For example, Figure 3A and Figure 3B The planar antenna 10a shown needs to control the on and off of eight diodes 220a. Figure 4A The planar antenna 10b shown also requires complex control lines to control the on and off of multiple diodes 200b respectively. However, the adjustment device 300 in the present application can adjust the square resistance of the first graphene component 200a and the square resistance of the second graphene component 200b through the voltage controller 310 and the DC bias line 320, and the control method is simple and the wiring complexity is small.

[0117] In some embodiments of the present application, the number of graphene components 200 may be four, and the four graphene components 200 can make the current synthesized by the first current I1 and the second current I2 more evenly distributed on the radiator 100, thereby further improving the effect of continuous regulation of the polarization state of the planar antenna 10. Fig. 8A and Figure 8B An exemplary arrangement of four graphene components 200 in an embodiment of the present application is shown, wherein: Fig. 8A is a top view of the planar antenna 10, Figure 8B FIG. 1 is an exploded view of the planar antenna 10. Fig. 8A and Figure 8B, the four graphene components 200 are respectively a first graphene component 200a, a second graphene component 200b, a third graphene component 200c and a fourth graphene component 200d. Among them, the orthographic projection S1 of the first graphene component 200a in the first plane S0, the orthographic projection S2 of the second graphene component 200b in the first plane S0, the orthographic projection S3 of the third graphene component 200c in the first plane S0 and the orthographic projection S4 of the fourth graphene component 200d in the first plane S0 do not overlap with each other.

[0118] The orthographic projection S1 of the first graphene component 200a in the first plane S0 and the orthographic projection S3 of the third graphene component 200c in the first plane S0 respectively overlap with the first radiation edge 110 in part; the orthographic projection S2 of the second graphene component 200b in the first plane S0 and the orthographic projection S4 of the fourth graphene component 200d in the first plane S0 respectively overlap with the second radiation edge 120 in part. In addition, along the A direction, the first graphene component 200a is farther away from the fourth graphene component 200d than the third graphene component 200c; the second graphene component 200b is closer to the first graphene component 200a than the fourth graphene component 200d.

[0119] Exemplarily, the radiator 100 is rectangular, and the first radiating side 110 and the second radiating side 120 are two opposite sides of the rectangular radiator 100 along the B direction. The orthographic projection S1 of the first graphene component 200a in the first plane S0 may be located at the lower right corner of the radiator 100, and the orthographic projection S2 of the second graphene component 200b in the first plane S0 may be located at the lower left corner of the radiator 100. The orthographic projection S3 of the third graphene component 200b in the first plane S0 may be located at the upper right corner of the radiator 100. The orthographic projection S4 of the fourth graphene component 200d in the first plane S0 may be located at the upper left corner of the radiator 100.

[0120] Similarly, the square resistance values ​​of the first graphene component 200a, the second graphene component 200b, the third graphene component 200c and the fourth graphene component 200d can be adjusted by the adjustment device 300 to change the distribution characteristics of the current on the radiator 100, thereby changing the polarization state of the planar antenna 10.

[0121] 9A to 9C FIG. 1 shows an exemplary distribution diagram of the current on the radiator 100 of the planar antenna 10 in different polarization states in the embodiment of the present application. For example, Fig. 9A As shown, when the square resistance of the first graphene component 200a is the same as that of the second graphene component 200b, there is no potential difference in the B direction, and the current distributed on the radiator 200 is the first current I1 along the A direction. The planar antenna 10 operates in a linear polarization state.

[0122] like Fig. 9B As shown, when the square resistance of the first graphene component 200a is greater than the square resistance of the second graphene component 200b, and the square resistance of the third graphene component 200c is less than the square resistance of the fourth graphene 200d. A second current I2 can be generated on the radiator 100. The second current I2 in the lower half of the radiator 100 flows from the first radiation edge 110 to the second radiation edge 120 along the B direction. The second current I2 in the upper half of the radiator 100 flows from the second radiation edge 120 to the first radiation edge 110 along the B direction. At this time, within a phase period, the current vector synthesized by the superposition of the first current I1 and the second current I2 rotates clockwise. The planar antenna 10 can operate in a left-handed elliptical polarization state.

[0123] like Fig. 9C As shown, when the square resistance of the first graphene component 200a is less than the square resistance of the second graphene component 200b, and the square resistance of the third graphene component 200c is greater than the square resistance of the fourth graphene 200d. A second current I2 can be generated on the radiator 100. The second current I2 in the lower half of the radiator 100 flows from the second radiation edge 120 to the first radiation edge 110 along the B direction. The second current I2 in the upper half of the radiator 100 flows from the first radiation edge 110 to the second radiation edge 120 along the B direction. At this time, within a phase period, the current vector synthesized by the superposition of the first current I1 and the second current I2 rotates counterclockwise. The planar antenna 10 can operate in a right-handed elliptical polarization state.

[0124] Continue reading Fig. 8A and Figure 8B Similarly, in some embodiments of the present application, along the A direction, the ratio between the distance between the first graphene component 200a and the second graphene component 200b and the size of the radiator 100 may be 0-0.5, for example, 0, 0.1, 0.2, etc.; the ratio between the distance between the third graphene component 200c and the fourth graphene component 200d and the size of the radiator 100 may be 0-0.5, for example, 0, 0.1, 0.2, etc. And, along the B direction, the ratio between the distance between the first graphene component 200a and the second graphene component 200b and the size of the radiator 100 may be 0.5-1, for example, 0.5, 0.6, 0.7, etc.; the ratio between the distance between the third graphene component 200c and the fourth graphene component 200d and the size of the radiator 100 may be 0.5-1, for example, 0.5, 0.6, 0.7, etc. Thereby, the planar antenna 10 can realize continuous regulation among right-hand circular polarization, right-hand elliptical polarization, linear polarization, left-hand elliptical polarization and left-hand circular polarization, further improving the effect of continuous regulation of polarization state and expanding the scope of application.

[0125] The regulating device 300 can also adjust the square resistance of the first graphene component 200a, the second graphene component 200b, the third graphene component 200c and the fourth graphene component 200d by voltage.

[0126] Specifically, the adjustment device 300 can transmit the first voltage V1 to the first graphene component 200a and the fourth graphene component 200d, and transmit the second voltage V2 to the second graphene component 200b and the third graphene component 200c. By controlling the magnitude of the first voltage V1, the square resistance of the first graphene component 200a and the square resistance of the fourth graphene component 200d can be adjusted; by controlling the magnitude of the second voltage V2, the square resistance of the second graphene component 200b and the square resistance of the third graphene component 200c can be adjusted, thereby achieving continuous regulation of the polarization state of the planar antenna 10.

[0127] Exemplarily, when the first voltage V1 and the second voltage V2 are both 0 V, the square resistance of the first graphene component 200a, the square resistance of the second graphene component 200b, the square resistance of the third graphene component 200c, and the square resistance of the fourth graphene component 200d are all 3000 ohm / sq. At this time, the axial ratio of the planar antenna 10 is approximately greater than 40 dB, and the planar antenna 10 can work in a linear polarization state.

[0128] When the first voltage V1 is 0V and the second voltage V2 varies between 0 and 5V, the polarization state of the planar antenna 10 can be continuously changed between linear polarization, left-handed elliptical polarization and left-handed circular polarization. For example, when the first voltage V1 is 0V and the second voltage V2 is 5V, the square resistance of the first graphene component 200a and the square resistance of the fourth graphene component 200d are both 3000ohm / sq, and the square resistance of the second graphene component 200b and the square resistance of the third graphene are both 400ohm / sq. At this time, the axial ratio of the planar antenna 10 is approximately less than 3dB, and the planar antenna 10 can work in a left-handed circular polarization state.

[0129] Conversely, when the first voltage V1 varies between 0 and 5V and the second voltage is 0V, the polarization state of the planar antenna 10 can be continuously changed between linear polarization, right-handed elliptical polarization and right-handed circular polarization. For example, when the first voltage V1 is 5V and the second voltage V2 is 0V, the square resistance of the first graphene component 200a and the square resistance of the fourth graphene component 200d are both 400ohm / sq, and the square resistance of the second graphene component 200b and the third graphene component 200c is 3000ohm / sq. At this time, the planar antenna 10 can work in the right-handed circular polarization state.

[0130] Fig. 10A according to Fig. 8A and Figure 8BA schematic diagram of the axial ratio of the planar antenna 10 in the embodiment of the present application when operating in left-hand circular polarization, right-hand circular polarization and linear polarization states is shown. Fig. 10B according to Fig. 8A and Figure 8B A schematic diagram of reflection coefficients when the planar antenna 10 in the embodiment of the present application works in left-hand circular polarization, right-hand circular polarization and linear polarization states is shown. Fig. 10C according to Fig. 8A and Figure 8B A schematic diagram of the radiation efficiency of the planar antenna 10 in the embodiment of the present application when operating in left-hand circular polarization, right-hand circular polarization and linear polarization states is shown. Fig. 10D according to Fig. 8A and Figure 8B The schematic diagram of the continuous change of the axial ratio of the planar antenna 10 in the embodiment of the present application is shown. It should be noted that: FIG. 10A to FIG. 10D Shown are various operating parameters of the planar antenna 10 when the center frequency is 1.60 GHz.

[0131] refer to Fig. 10A When the planar antenna 10 works in the left-hand circular polarization state and the right-hand circular polarization state, the minimum axial ratio can be less than 3dB, and the circular polarization effect of the planar antenna 10 is good. When the planar antenna 10 works in the linear polarization state, the axial ratio can be greater than 60dB, and the linear polarization effect of the planar antenna 10 is good.

[0132] refer to Fig. 10B , the reflection coefficient curve of the planar antenna 10 working in the left-hand circular polarization state, the reflection coefficient curve of the planar antenna 10 working in the right-hand circular polarization state, and the reflection coefficient curve of the planar antenna 10 working in the linear polarization state are relatively close. Therefore, when the planar antenna 10 continuously switches between the left-hand circular polarization state, the right-hand circular polarization state, and the linear polarization state, the reflection coefficient will not fluctuate greatly, thereby effectively ensuring the working stability of the planar antenna 10 and improving the working performance of the planar antenna 10.

[0133] refer to Fig. 10C Whether working in a left-hand circular polarization state, a right-hand circular polarization state, or a linear polarization state, the planar antenna 10 can maintain good radiation efficiency and good working performance. For example, when the planar antenna 10 works in a left-hand circular polarization state or a right-hand circular polarization state, the radiation efficiency is approximately greater than 0.2. For another example, when the planar antenna 10 works in a linear polarization state, the radiation efficiency is approximately greater than 0.3.

[0134] refer to Fig. 10D, when the first voltage V1 remains unchanged at 0V and the second voltage V2 gradually decreases from 5V to 0V, the square resistance of the first graphene component 200a and the square resistance of the fourth graphene component 200d both remain unchanged at 3000ohm / sq, and the square resistance of the second graphene component 200b and the square resistance of the third graphene component 200c both increase successively by 400ohm / sq, 800ohm / sq, 1000ohm / sq, 1500ohm / sq, 2000ohm / sq, and 3000ohm / sq. At this time, the axial ratio of the planar antenna 10 also gradually increases. The polarization state of the planar antenna 10 can gradually change to left-handed circular polarization, left-handed elliptical polarization, and linear polarization in sequence, and the effect of continuous regulation of the polarization state of the planar antenna 10 is good.

[0135] For example, Fig.11A according to Figure 3A and Figure 3B A schematic diagram of the axial ratio of the planar antenna 10a in some embodiments is shown. Fig. 11B according to Figure 4C Schematic diagrams of the axial ratio of the planar antenna 10b in some other embodiments are shown. Fig.11A and Fig. 11B Although the minimum axial ratio of the planar antenna 10a and the planar antenna 10b is less than 3dB, the circular polarization can be controlled. However, the axial ratio of the planar antenna 10a and the planar antenna 10b cannot be gradually changed, and the planar antenna 10a and the planar antenna 10b can only achieve discrete changes in linear polarization and circular polarization, and the control effect is limited.

[0136] In the present application, the planar antenna 10 can realize continuous transformation of polarization state. Fig. 10D and Fig.11A , Fig. 11B The axial ratio of the planar antenna 10 provided in the present application can be continuously variable, thereby realizing continuous regulation of the polarization state, and the polarization regulation effect is good, which effectively expands the scope of application and can meet the working requirements in different application scenarios.

[0137] Continue reading Figure 5A , Figure 5B , Fig. 8A and Figure 8BIn some embodiments of the present application, the graphene component 200 may include multiple layers of graphene 210 stacked along the C direction (as the third direction). In addition, a separator paper 220 is provided between two adjacent layers of graphene 210. The separator paper 220 is usually soaked in an ionic liquid to further expand the range of variation of the square resistance value of the graphene component 200, thereby enhancing the regulation effect of the polarization state of the planar antenna 10. For example, the graphene component 200 may include two layers of graphene 210. A separator paper 220 is provided between the two layers of graphene 210. Alternatively, in other embodiments, the graphene component 200 may also include only one layer of graphene 210, which is not limited in the present application. Wherein, the C direction is perpendicular to the first plane S0.

[0138] In some embodiments of the present application, the square resistance value of the graphene component 200 can vary from 1ohm / sq to 1Mohm / sq, so as to further enhance the regulation effect of the polarization state of the planar antenna 10. Exemplarily, the square resistance value variation range of the graphene component 200 can be enhanced by improving the manufacturing process of the graphene component 200. For example, the preparation temperature and formula of the graphene 210 in the graphene component 200 are regulated. For another example, the composition of the ionic liquid in which the diaphragm paper 210 in the graphene component 200 is changed, and the present application does not limit this.

[0139] Exemplarily, when the first voltage V1 and the second voltage V2 are both 0 V, the square resistance of the first graphene component 200a, the square resistance of the second graphene component 200b, the square resistance of the third graphene component 200c, and the square resistance of the fourth graphene component 200d are all 1 Mohm / sq. At this time, the planar antenna 10 can work in a linear polarization state, and the axial ratio of the planar antenna 10 is approximately greater than 40 dB.

[0140] When the first voltage V1 is 0V and the second voltage V2 varies between 0 and 5V, the polarization state of the planar antenna 10 can continuously vary between linear polarization, left-handed elliptical polarization, and left-handed circular polarization. For example, when the first voltage V1 is 0V and the second voltage V2 is 5V, the square resistance of the first graphene component 200a and the square resistance of the fourth graphene component 200d are both 1Mohm / sq, and the square resistance of the second graphene component 200b and the square resistance of the third graphene are both 1ohm / sq. At this time, the planar antenna 10 can operate in a left-handed circular polarization state, and the axial ratio of the planar antenna 10 is approximately less than 3dB.

[0141] Conversely, when the first voltage V1 varies between 0 and 5V and the second voltage is 0V, the polarization state of the planar antenna 10 can continuously vary between linear polarization, right-hand elliptical polarization, and right-hand circular polarization. For example, when the first voltage V1 is 5V and the second voltage V2 is 0V, the square resistance of the first graphene component 200a and the square resistance of the fourth graphene component 200d are both 1Mohm / sq, and the square resistance of the second graphene component 200b and the third graphene component 200c is 1ohm / sq. At this time, the planar antenna 10 can operate in a right-hand circular polarization state, and the axial ratio of the planar antenna 10 is approximately less than 3dB.

[0142] Fig. 12A according to Fig. 8A and Figure 8B A schematic diagram of the axial ratio of the planar antenna 10 in the embodiment of the present application when operating in circular polarization is shown. Fig. 12B according to Fig. 8A and Figure 8B A schematic diagram of the reflection coefficient when the planar antenna 10 works in circular polarization in an embodiment of the present application is shown. Fig. 12C according to Fig. 8A and Figure 8B FIG. 1 is a schematic diagram showing the radiation efficiency of the planar antenna 10 in the embodiment of the present application when it works in circular polarization. It should be noted that: FIG. 12A to FIG. 12C The square resistance values ​​of the first graphene component 200a, the second graphene component 200b, the third graphene component 200c and the fourth graphene component 200d in the planar antenna 10 are all in the range of 1 ohm / sq to 1 Mohm / sq. FIG. 12A to FIG. 12C When the planar antenna 10 works in the circular polarization state, the minimum value of the axial ratio is about 1dB, and the polarization control effect of the planar antenna 10 is good; the minimum value of the reflection coefficient is about -15dB, and the working performance of the planar antenna 10 is good; the radiation efficiency is as high as 0.9, and the radiation efficiency of the planar antenna 10 is high.

[0143] Continue reading Figure 5A and Fig. 8A In this embodiment, when the radiator 100 is rectangular and the number of graphene components 200 is two, the orthographic projections (for example, orthographic projection S1 and orthographic projection S2) of the two graphene components 200 in the first plane S0 overlap at least partially with the two vertex corners of the radiator 100 respectively. The orthographic projections of the two graphene components 200 in the first plane S0 are symmetrically distributed with respect to the symmetry axis L1 of the radiator 100. When the number of graphene components 200 is four, the orthographic projections (for example, orthographic projections S1 to S4) of the four graphene components 200 in the first plane S0 overlap at least partially with the four vertex corners of the radiator 100 respectively. The orthographic projections of the four graphene components 200 in the first plane S0 are symmetrically distributed with respect to the symmetry axis L1 of the radiator 100. In other embodiments, the graphene components 200 may also be disposed at other positions.

[0144] For example, Fig.13A FIG. 1 shows an exemplary layout of the graphene assembly 200 in an embodiment of the present application. Fig.13A , the orthographic projections of the four graphene components 200 in the first plane S0 may respectively overlap at least partially with both ends of the first radiation edge 110 and both ends of the second radiation edge 120. For example, the orthographic projection S1 of the first graphene component 200a in the first plane S0 and the orthographic projection S3 of the third graphene component 200c in the first plane S0 respectively overlap at least partially with both ends of the first radiation edge 110; the orthographic projection S2 of the second graphene component 200b in the first plane S0 and the orthographic projection S4 of the fourth graphene component 200d in the first plane S0 respectively overlap at least partially with both ends of the second radiation edge 120.

[0145] Another example: Fig. 13B FIG. 2 shows an exemplary layout of the graphene assembly 200 in the embodiment of the present application. Fig. 13B , the orthographic projections of the four graphene components 200 in the first plane S0 may also be asymmetrically distributed relative to the symmetry axis L1 of the radiator 100. For example, the orthographic projection S1 of the first graphene component 200a in the first plane S0 is slightly offset along the A direction relative to the orthographic projection S2 of the second graphene component 200b in the first plane S0; the orthographic projection S3 of the third graphene component 200c in the first plane S0 is slightly offset along the A direction relative to the orthographic projection S4 of the fourth graphene component 200d in the first plane S0.

[0146] It is understandable that the above Fig.13A and Fig. 13B Only four graphene components 200 are used as an example to introduce the layout of the graphene components 200. When there are two graphene components 200, the above Fig.13A and Fig. 13B The layout is not described in detail.

[0147] Fig.14A according to Fig. 8A , Fig.13A and Fig. 13B A schematic diagram of the axial ratio of the planar antenna 10 in different graphene component 200 layouts in the embodiment of the present application is shown. Fig. 14B according to Fig. 8A , Fig.13A and Fig. 13B A schematic diagram of the reflection coefficient of the planar antenna 10 under different layouts of the graphene components 200 in the embodiment of the present application is shown. Fig. 14C according to Fig. 8A , Fig.13A and Fig. 13BFIG. 2 shows a schematic diagram of the radiation efficiency of the planar antenna 10 in different layouts of the graphene components 200 in the embodiment of the present application. FIG. 14A to FIG. 14C Whether the four graphene components 200 are respectively arranged at the four vertices of the radiator 100, or the four graphene components 200 are respectively arranged at the two ends of the first radiation edge 110 and the two ends of the second radiation edge 120, or the four graphene components 200 are asymmetrically distributed relative to the symmetry axis L1 of the radiator 100, the minimum value of the axial ratio of the planar antenna 10 in the circular polarization state is less than 3dB, the reflection coefficient is less than -10dB, and the radiation efficiency is greater than 0.2. Therefore, the planar antenna 10 can have a good effect of continuous polarization state regulation and good working performance, and has a wide range of applications.

[0148] Continue reading Figure 5B and Figure 8B In some embodiments of the present application, the planar antenna 10 further includes a first dielectric plate 500 and a ground plate 600. Along the C direction, the radiator 100, the first dielectric plate 500 and the ground plate 600 are stacked in sequence. The graphene component 200 may also be disposed between the first dielectric plate 500 and the ground plate 600, and the graphene component 200 and the ground plate 600 are insulated from each other to ensure that the graphene component 200 does not interfere with the ground plate 600. Exemplarily, a second dielectric plate 700 may be disposed between the graphene component 200 and the ground plate 600. The graphene component 200 may be insulated from the ground plate 600 through the second dielectric plate 7000.

[0149] or, Fig.15 FIG. 2 shows an exemplary configuration of the graphene assembly 200 in some other embodiments of the present application. Fig.15 The graphene component 200 may be located on the side of the radiator 100 facing away from the first dielectric plate 500. In addition, an insulating layer (not shown) is provided between the graphene component 200 and the radiator 100 so that the graphene component 200 can be insulated from the radiator 100. Fig.15 The axial ratio change, reflection coefficient and radiation efficiency of the planar antenna 10 shown in FIG. FIG. 10A to FIG. 10D And the related descriptions are not repeated here.

[0150] In some embodiments of the present application, the shape of the radiator 100 may include but is not limited to any one or more of a rectangular, circular or polygonal shape.

[0151] In some embodiments of the present application, the shape of the orthographic projection of the graphene component 200 in the first plane S0 (for example, the orthographic projections S1 to S4 described above) includes but is not limited to any one or more of a rectangle, a sector, a circle or a polygon.

[0152] It should be noted that the above embodiments are only illustrative of the planar antenna 10 including two or four graphene components 200, and those skilled in the art may make other modifications. For example, in other embodiments, the planar antenna 10 may also include only one graphene component 200. Fig.16 FIG. 2 shows a schematic diagram of a planar antenna 10 including a graphene component 200 in an embodiment of the present application. Fig.16 , the orthographic projection S of the graphene component 200 in the first plane S0 may at least partially overlap with the first radiation edge 110. The adjustment device 300 is connected to the graphene component 200 to adjust the square resistance of the graphene component 200, thereby achieving continuous regulation of the linear polarization, left-handed elliptical polarization, and left-handed circular polarization of the planar antenna 10. For the specific principle, please refer to Fig. 6A and Figure 6B And the related descriptions are not repeated here.

[0153] Alternatively, in other alternative embodiments, the orthographic projection S of the graphene component 200 in the first plane may also overlap at least partially with the second radiation edge 120. By adjusting the square resistance value of the graphene component 200, the linear polarization, right-handed elliptical polarization, and left-handed elliptical polarization of the planar antenna 10 can be continuously controlled. For the specific principle, please refer to Fig. 6A and Figure 6C And the related descriptions are not repeated here.

[0154] The above is an explanation of the implementation mode of the present application by specific specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Although the description of the present application will be introduced in conjunction with some embodiments, this does not mean that the features of this application are limited to the implementation mode. On the contrary, the purpose of introducing the application in conjunction with the implementation mode is to cover other options or modifications that may be extended based on the claims of the present application. The present application can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present application, some specific details are omitted in the description. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0155] In the description of the present application, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "outside", "inside", "circumferential", "radial", "axial" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0156] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "setting", "installation", "connection" and "fitting" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0157] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A planar antenna, characterized in that: It comprises a radiator, at least two graphene components and an adjusting device; wherein: The radiator is located in a first plane, and an electrical signal is fed into the radiator through a feeding point located at a first position so as to generate a first current along a first direction, wherein the first direction is parallel to the first plane; Along a second direction, the radiator includes a first radiating edge and a second radiating edge located on both sides of the feeding point, and the second direction is parallel to the first plane and perpendicular to the first direction; The two graphene components are respectively insulated and connected to the radiator, and an orthographic projection of one of the two graphene components in the first plane at least partially overlaps with the first radiation edge, and an orthographic projection of the other graphene component in the first plane at least partially overlaps with the second radiation edge; The adjusting device is connected to the two graphene components and is used to adjust the square resistance values ​​of the two graphene components.

2. The planar antenna according to claim 1, characterized in that: Along the first direction, a ratio between a distance between two graphene components and a size of the radiator is 0 to 0.

5.

3. The planar antenna according to claim 2, characterized in that: Along the second direction, a ratio between a distance between two graphene components and a size of the radiator is 0.5-1.

4. The planar antenna according to claim 1, characterized in that: The regulating device is used to transmit a first voltage to one of the two graphene components and transmit a second voltage to the other graphene component. The regulating device can control the magnitude of the first voltage and the second voltage to adjust the square resistance values ​​of the two graphene components.

5. The planar antenna according to claim 4, characterized in that: The regulating device comprises a voltage controller and a DC bias line, and the voltage controller is connected to the two graphene components through the DC bias line.

6. The planar antenna according to claim 1, characterized in that: The number of the graphene components is four, the orthographic projections of the four graphene components in the first plane do not overlap with each other, and the four graphene components are respectively a first graphene component, a second graphene component, a third graphene component and a fourth graphene component, wherein: The orthographic projections of the first graphene component and the third graphene component in the first plane overlap at least partially with the first radiation edge, respectively, and the orthographic projections of the second graphene component and the fourth graphene component in the first plane overlap at least partially with the second radiation edge, respectively, and, along the first direction, the first graphene component is farther away from the fourth graphene component than the third graphene component, and the second graphene component is closer to the first graphene component than the fourth graphene component; The regulating device is used to deliver a first voltage to the first graphene component and the fourth graphene component, and to deliver a second voltage to the second graphene component and the third graphene component.

7. The planar antenna according to claim 6, characterized in that: Along the first direction, a ratio of a distance between the first graphene component and the second graphene component to a size of the radiator is 0 to 0.5, and a ratio of a distance between the third graphene component and the fourth graphene component to the size of the radiator is 0 to 0.5; Along the second direction, a ratio of a distance between the first graphene component and the second graphene component to a size of the radiator is 0.5-1, and a ratio of a distance between the third graphene component and the fourth graphene component to a size of the radiator is 0.5-1.

8. The planar antenna according to claim 1, characterized in that: The square resistance value of the graphene component varies in the range of 1 ohm / sq to 1 Mohm / sq.

9. The planar antenna according to claim 1, characterized in that: The graphene assembly includes a layer of graphene, or includes multiple layers of graphene stacked along a third direction, and a separator paper is arranged between two adjacent layers of graphene, and the third direction is perpendicular to the first plane.

10. The planar antenna according to claim 1, characterized in that: The planar antenna comprises a first dielectric plate and a ground plate, wherein the radiator, the first dielectric plate and the ground plate are stacked in sequence along a third direction, and the third direction is perpendicular to the first plane; The graphene component is located on a side of the radiator facing away from the first dielectric plate, and an insulating layer is provided between the graphene component and the radiator; or, the graphene component is located between the first dielectric plate and the grounding plate, and the graphene component and the grounding plate are insulated and connected.

11. The planar antenna according to claim 10, characterized in that: A second dielectric plate is provided between the graphene component and the ground plate.

12. The planar antenna according to claim 1, characterized in that: The shape of the orthographic projection of the graphene component in the first plane includes any one or more of a rectangle, a circle, a sector or a polygon.

13. The planar antenna according to claim 1, characterized in that: The shape of the radiator includes any one or more of a rectangle, a circle or a polygon.

14. The planar antenna according to claim 1, characterized in that: The planar antenna is a patch antenna or a planar inverted-F antenna.

15. A planar antenna, characterized in that: It includes a radiator, a graphene component and an adjusting device; wherein: The radiator is located in a first plane, and an electrical signal is fed into the radiator through a feeding point located at a first position so as to generate a first current along a first direction, wherein the first direction is parallel to the first plane; Along a second direction, the radiator includes a first radiating edge and a second radiating edge located on both sides of the feeding point, and the second direction is parallel to the first plane and perpendicular to the first direction; The graphene component is insulated from the radiator, and an orthographic projection of the graphene component in the first plane at least partially overlaps with the first radiation edge or the second radiation edge; The adjusting device is connected to the graphene component and is used to adjust the square resistance value of the graphene component.

16. A terminal, characterized in that: The invention comprises a housing and the planar antenna according to any one of claims 1 to 15, wherein the planar antenna is arranged on the housing.

Images