A low-temperature anti-jitter liquid metal reconfigurable antenna and a reconfiguration method thereof

Abstract

The present invention discloses a low-temperature anti-shake liquid metal reconfigurable antenna and a reconstruction method thereof, which belongs to the field of reconfigurable antennas and includes a liquid metal container, a patch antenna radiator, a back cavity gap structure, a liquid metal channel and a metal floor. The top of the liquid metal container is connected with a liquid metal injection valve and a discharge valve; the liquid metal container is directly connected to the patch antenna radiator and the metal floor; the liquid metal channel is located inside the liquid metal container and the liquid metal channel is directly connected to the patch antenna radiator and the metal floor; the back cavity gap structure is etched on the patch antenna radiator. The liquid metal part in the present invention only serves as a "switch" for switching the working state of the antenna radiator. When the temperature changes, the thermal expansion and contraction effect of the liquid metal will not affect the size of the established antenna, and even if the liquid metal solidifies in the channel, it will not have an adverse effect on the working state of the antenna.

Description

Technical Field

[0001] The invention belongs to the field of reconfigurable antennas, and relates to a low-temperature anti-jitter liquid metal reconfigurable antenna and a reconstruction method thereof. Background Art

[0002] In order to realize the vision of communication anytime and anywhere, giant low-orbit satellite constellations are being deployed in full swing. Once completed, high-speed communication in remote areas such as deserts, rainforests, and polar regions will become a reality. However, challenges also arise from opportunities, and more and more requirements are put forward for antenna design, including but not limited to multi-band / multi-polarization antenna radiation patterns, integration of multiple antennas in a limited space, heat dissipation, etc. Reconfigurable antennas, especially reconfigurable antennas based on liquid metal, are one of the alternative solutions to solve the integration of multiple antennas. Through external drive control means, the functions of multiple antennas can be realized, such as polarization switchable, frequency switchable, etc.

[0003] Compared with the water antenna, which is also a liquid antenna, the dielectric constant of water is higher and the efficiency of the antenna is low, while the high conductivity of liquid metal can ensure the efficiency of the antenna; secondly, compared with the melting point of the water antenna at zero degrees Celsius, the melting point of liquid metals such as gallium metal alloys can be as low as minus 28 degrees Celsius. Gallium indium tin alloy can always be in liquid state at room temperature and can meet most application scenarios of the antenna. That is, the temperature application range of liquid metal is wider and it is more suitable for communications in medium and high dimensional areas.

[0004] In order to realize a reconfigurable antenna based on liquid metal, the existing technology usually treats liquid metal as an antenna radiator or feeder to realize the switchable antenna radiation state. However, the size of the antenna directly determines the working frequency band of the antenna. When the temperature changes, the liquid metal will inevitably undergo thermal expansion and contraction. At the same time, the existing liquid metal antennas mostly use microfluidic technology. Even a small volume change will be amplified and reflected in the size of the antenna radiator or antenna feeder, causing unexpected changes to the working state of the antenna. For example, when liquid metal is used as the dipole arm of a dipole antenna, under the microfluidic process, the thermal expansion and contraction of the liquid metal will significantly lengthen / shorten the dipole arm of the dipole antenna, and the antenna working frequency band will be frequency-shifted. In addition, when the existing liquid metal reconfigurable antenna works below the freezing point, the liquid metal will condense into a solid state, and the liquid metal will undergo significant volume expansion, which will not only bring unexpected changes to the working state of the antenna, but also have the risk of damaging the microfluidic channel and causing permanent damage. Finally, due to the fluidity of liquid metal, when liquid metal is used as an antenna radiator or feeder, in order to achieve continuous coordination, the liquid metal usually does not fill the entire microchannel. When the antenna posture changes, such as rotation, jitter, or shaking, the liquid metal serving as the antenna radiator / antenna feeder may be cut off or change position, causing the antenna to fail to work, poor matching, and reduced gain. Therefore, the practical scenarios of such antennas are very limited.

[0005] In order to expand the application scope of antennas, overcome the attitude and temperature limitations of traditional reconfigurable antennas, and enable low-orbit satellite constellations to be truly widely used in various scenarios, such as detection communications in remote areas and high-latitude areas, the present invention discloses a low-temperature anti-jitter liquid metal reconfigurable antenna, including a cavity-backed slot antenna and a patch antenna and a reconstruction method thereof. Compared with existing liquid metal-based reconfigurable antennas, the present invention has a wider range of application scenarios and is not limited by antenna attitude and low-temperature environments. Summary of the invention

[0006] The purpose of the present invention is to provide a low-temperature anti-shake liquid metal reconfigurable antenna and a reconstruction method thereof, which solves the problem that the traditional liquid metal reconfigurable antenna is subject to posture and temperature restrictions when in use.

[0007] The technical solution adopted by the present invention is as follows:

[0008] A low-temperature anti-shake liquid metal reconfigurable antenna comprises a liquid metal container, a patch antenna radiator, a back cavity gap structure, a liquid metal channel and a metal floor, wherein the top of the liquid metal container is connected to a liquid metal injection valve and a liquid metal discharge valve;

[0009] The liquid metal container is directly connected to the patch antenna radiator and the metal floor;

[0010] The liquid metal channel is located inside the liquid metal container and the liquid metal channel is directly connected to the patch antenna radiator and the metal floor;

[0011] The back cavity gap structure is etched on the patch antenna radiator;

[0012] When the liquid metal channel is filled with liquid metal, the liquid metal is in full contact with the patch antenna radiator and the metal floor, forming a cavity-backed slot antenna structure, and the antenna working mode is the cavity-backed slot antenna mode;

[0013] When the liquid metal is exhausted from the liquid metal channel, the patch antenna radiator and the metal floor cannot form a closed state through the liquid metal, and the antenna working mode is the patch antenna mode.

[0014] The present invention realizes the switching between the patch antenna and the back cavity slot antenna by injecting or draining the liquid metal, so as to achieve the characteristics of antenna polarization reconfiguration or frequency reconfiguration; unlike the traditional liquid metal reconfigurable antenna which uses liquid metal as the antenna radiator, the liquid metal part in the present invention only serves as a "switch" to switch the working state of the antenna radiator. The thermal expansion and contraction effect of the liquid metal when the temperature changes will not affect the size of the established antenna, and even if the liquid metal solidifies in the channel, it will not have a negative impact on the working state of the antenna. Since in the two working states of the antenna, the liquid metal in the liquid metal channel only exists in two states: full and drained, that is, the working state of the antenna will not be affected by changes in the antenna posture such as rotation, shaking, etc.

[0015] Furthermore, the radiation forms of the cavity-backed slot antenna and the patch antenna both adopt a coaxial feeding method, and when reconfigured, they are switched to corresponding coaxial connectors.

[0016] In order to ensure that the antenna still has good matching performance under the expansion and contraction effect, the reconfigurable antenna does not use liquid metal reconstruction feeder. Both antenna radiation forms adopt coaxial feeding. When reconstructing, the frequency polarization reconfigurable antenna needs to switch to the corresponding coaxial connector.

[0017] Furthermore, the slit modes of the back cavity slot structure include but are not limited to vertical slit / polarization, horizontal slit / polarization, and 45-degree slit / polarization.

[0018] The slitting method of the back cavity slot structure is not unique, and thus the polarization method achieved is also not unique. The slitting methods include but are not limited to vertical slitting, horizontal slitting, and 45-degree slitting. The polarization methods include but are not limited to vertical polarization, horizontal polarization, and 45-degree polarization. Vertical slitting corresponds to horizontal polarization, horizontal slitting corresponds to vertical polarization, +45-degree slit corresponds to -45-degree polarization, and -45-degree slit corresponds to +45-degree polarization. During design, the corresponding reconfigurable method can be selected according to the actual application scenario.

[0019] Furthermore, the liquid metal container surrounds the patch antenna radiator and is 0.5 mm higher than the patch antenna radiator.

[0020] Furthermore, the liquid metal channel that determines the operating frequency band of the cavity-backed slot antenna mode is always located outside the patch antenna radiator and in direct contact with the patch antenna radiator, and the liquid metal channel includes various sizes.

[0021] The liquid metal channel that determines the working frequency band of the cavity-backed slot antenna is always located outside the patch antenna radiator and in direct contact with it, and the size of the liquid metal channel is not unique, that is, the corresponding reconstructed frequency band can be selected by adjusting the liquid metal channel.

[0022] Furthermore, the patch antenna radiator has a width of 7 mm in the x-direction, and the back cavity slot structure has a length of 4.5 mm in the y-direction and is offset from the center by 0.3 mm.

[0023] The method for reconfiguring a low-temperature anti-jitter liquid metal reconfigurable antenna comprises the following steps:

[0024] When the antenna is reconstructed, liquid metal is injected into or exhausted from the liquid metal channel in the liquid metal container by injection or extrusion;

[0025] When the liquid metal channel is filled with liquid metal, the liquid metal is in full contact with the patch antenna radiator and the metal floor, forming a cavity-backed slot antenna structure, and the antenna works in the cavity-backed slot antenna mode;

[0026] When the liquid metal is exhausted from the liquid metal channel, the patch antenna radiator and the metal floor cannot form a closed state through the liquid metal, and the antenna works in the patch antenna mode.

[0027] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0028] 1. A low-temperature anti-shake liquid metal reconfigurable antenna realizes switching between a patch antenna and a back cavity slot antenna by injecting or draining liquid metal, solving the problem of posture and temperature limitations of existing traditional reconfigurable antennas in certain application scenarios. The implementation method of the present invention is simple and has strong reliability.

[0029] 2. Compared with the existing liquid metal reconfigurable antenna, the present invention has a wider application scenario, is not limited by the antenna posture and low temperature environment, and has good robustness. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative work, among which:

[0031] Figure 1 A three-dimensional view of a low-temperature anti-shake liquid metal reconfigurable antenna according to the present invention;

[0032] Figure 2 An exploded diagram of a liquid metal container 101, a liquid metal channel 201, a liquid metal injection / discharge valve and a metal floor of a low-temperature anti-shake liquid metal reconfigurable antenna according to the present invention;

[0033] Figure 3 This is a cross-sectional view of a low-temperature anti-jitter liquid metal reconfigurable antenna of the present invention;

[0034] Figure 4 The present invention discloses several selectable slotting modes for a low-temperature anti-jitter liquid metal reconfigurable antenna.

[0035] Markings in the figure: 101-liquid metal container, 102-patch antenna radiator, 103-back cavity gap structure, 201-liquid metal channel, 202-injection valve, 203-discharge valve, 301-metal floor, 401-coaxial connector. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical scheme and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, that is, the embodiments described are only part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0037] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0038] It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0039] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0040] Example 1

[0041] A preferred embodiment of the present invention provides a low-temperature anti-shake liquid metal reconfigurable antenna, comprising a liquid metal container 101, a patch antenna radiator 102, a back cavity gap structure 103, a liquid metal channel 201 and a metal floor 301. The top of the liquid metal container 101 is connected to a liquid metal injection valve 202 and a discharge valve 203;

[0042] The liquid metal container 101 is directly connected to the patch antenna radiator 102 and the metal floor 301;

[0043] The liquid metal channel 201 is located inside the liquid metal container 101 and the liquid metal channel 201 is directly connected to the patch antenna radiator 102 and the metal floor 301;

[0044] The back cavity gap structure 103 is etched on the patch antenna radiator 102;

[0045] When the liquid metal channel 201 is filled with liquid metal, the liquid metal is in full contact with the patch antenna radiator 102 and the metal floor 301 to form a cavity-backed slot antenna structure, and the antenna working mode is a cavity-backed slot antenna mode;

[0046] When the liquid metal is exhausted from the liquid metal channel 201 , the patch antenna radiator 102 and the metal floor 301 cannot form a closed state through the liquid metal, and the antenna working mode is the patch antenna mode.

[0047] Figure 1The present invention is a three-dimensional view of a low-temperature anti-shake liquid metal reconfigurable antenna (the liquid metal injection valve 202 and the discharge valve 203 are omitted in the figure), which mainly includes a liquid metal container 101, a patch antenna radiator 102 and a back cavity gap structure 103; there are three layers of dielectric substrates and two layers of prepreg, and the bottom dielectric substrate only plays the role of supporting the metal floor 301, so low-cost FR-4 is used as the dielectric substrate; the material of the liquid metal container 101 is PDMS, and it is spin-coated from the metal floor to the patch antenna based on 3D printing technology. The line radiator 102, the liquid metal injection valve 202 and the discharge valve 203 are located on the top of the liquid metal container 101. The liquid metal container 101 surrounds the patch antenna radiator 102 and is 0.5mm higher than the patch antenna radiator. The liquid metal container 101 is directly connected to the patch antenna radiator 102 and the metal floor 301. At the same time, the back cavity gap structure 103 is etched on the patch antenna radiator 102. The width of the patch antenna radiator 102 in the x direction is 7mm, and the length of the back cavity gap structure 103 is 4.5mm and offset from the center by 0.3mm.

[0048] Figure 2 It is an exploded view of a liquid metal container 101, a liquid metal channel 201, a liquid metal injection / exhaust valve and a metal floor 301 of a low-temperature anti-shake liquid metal reconfigurable antenna of the present invention.

[0049] Figure 3 The partial positional relationship of the liquid metal container 101, the liquid metal channel 201, the injection valve 202, the discharge valve 203 and the metal floor 301 is shown, wherein the liquid metal channel 201 is located inside the liquid metal container 101 and is directly connected to the patch antenna radiator 102 and the metal floor 301. When the antenna is reconstructed, it is only necessary to inject / drain the liquid metal into the liquid metal channel 201 in the liquid metal container 101 by means of a syringe / extrusion. When the liquid metal channel 201 is filled with liquid metal, the liquid metal is in full contact with the patch antenna radiator 102 and the metal floor layer to form a back cavity slot antenna structure, and the antenna works in the back cavity slot antenna mode; when the liquid metal channel 201 is completely drained of liquid metal, the patch antenna radiator 102 and the metal floor layer cannot form a closed state through the liquid metal, and the antenna works in the patch antenna mode.

[0050] Figure 3This is a cross-sectional view of a low-temperature anti-jitter liquid metal reconfigurable antenna of the present invention (the liquid metal injection / exhaust valve is omitted in the figure); the back cavity slot antenna and the patch antenna are both fed by a coaxial probe, and when reconfigured, they are switched to the corresponding coaxial connector 401; in the processing, the metallized through-hole method is used for simulation, and the dotted lines in the figure are the coaxial feeding probe (thin) and the coaxial feeding shell (thick), respectively, wherein the coaxial feeding probe of the patch antenna passes through three layers of dielectrics and is in direct contact with the patch antenna radiator 102, the coaxial feeding probe of the back cavity slot antenna passes through the middle layer dielectric and the bottom layer dielectric, and is not in direct contact with the patch antenna radiator 102 and the metal floor, and the coaxial feeding shells of the patch antenna and the back cavity slot antenna are located in the bottom layer dielectric, in direct contact with the metal floor, and are fixed by the bottom coaxial connector 401 pad. When reconfiguring the antenna, it is only necessary to switch to the corresponding feeding channel.

[0051] Figure 4 The present invention provides several selectable slit methods for a low-temperature anti-jitter liquid metal reconfigurable antenna. The slit method of the back cavity slot structure 103 is not unique, and thus the polarization method achieved is also not unique, including but not limited to vertical slit / polarization, horizontal slit / polarization, 45-degree slit / polarization, etc.; the liquid metal channel 201 that determines the working frequency band of the back cavity slot antenna is always located outside the patch antenna radiator 102 and in direct contact with it, and the size of the liquid metal channel 201 is not unique, that is, the corresponding reconstructed frequency band can be selected by adjusting the liquid metal channel 201 during design.

[0052] In order to solve the problems of posture and temperature limitations of traditional reconfigurable antennas during use, the present invention designs an anti-jitter liquid metal reconfigurable antenna that can be used in low temperatures. The switching between the patch antenna and the back cavity slot antenna is achieved by injecting or discharging liquid metal to achieve the characteristics of reconfigurable antenna polarization or reconfigurable frequency. It has a wider range of application scenarios and is not limited by antenna posture or low temperature environment.

[0053] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions and improvements made by any technician familiar with the field within the spirit and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A low-temperature anti-shake liquid metal reconfigurable antenna, characterized in that: The device comprises a liquid metal container (101), a patch antenna radiator (102), a back cavity gap structure (103), a liquid metal channel (201) and a metal floor (301); the top of the liquid metal container (101) is connected to a liquid metal injection valve (202) and a liquid metal discharge valve (203); and the liquid metal container (101) surrounds the patch antenna radiator (102); The liquid metal container (101) is directly connected to the patch antenna radiator (102) and the metal floor (301); The liquid metal channel (201) is located inside the liquid metal container (101), and the liquid metal channel (201) is directly connected to the patch antenna radiator (102) and the metal floor (301); The back cavity gap structure (103) is etched on the patch antenna radiator (102); When the liquid metal channel (201) is filled with liquid metal, the liquid metal is in full contact with the patch antenna radiator (102) and the metal floor (301), forming a back cavity slot antenna structure, and the antenna working mode is a back cavity slot antenna mode; When the liquid metal is completely drained from the liquid metal channel (201), the patch antenna radiator (102) and the metal floor (301) cannot be closed by the liquid metal, and the antenna working mode is a patch antenna mode.

2. According to claim 1, a low-temperature anti-jitter liquid metal reconfigurable antenna is characterized in that: The radiation forms of the cavity-backed slot antenna and the patch antenna both adopt a coaxial feeding method, and when reconfiguring, they are switched to a corresponding coaxial connector (401).

3. The anti-jitter liquid metal reconfigurable antenna that can be used at low temperatures according to claim 1, characterized in that: The slit mode of the back cavity slot structure (103) includes vertical slit / polarization, horizontal slit / polarization or 45-degree slit / polarization.

4. The anti-jitter liquid metal reconfigurable antenna that can be used at low temperatures according to claim 1, characterized in that: The liquid metal container (101) is 0.5 mm higher than the patch antenna radiator (102).

5. The anti-jitter liquid metal reconfigurable antenna that can be used at low temperatures according to claim 1, characterized in that: The liquid metal channel (201) that determines the operating frequency band of the cavity-backed slot antenna mode is always located outside the patch antenna radiator (102) and is in direct contact with the patch antenna radiator (102).

6. A method for reconfiguring a low-temperature anti-jitter liquid metal reconfigurable antenna as claimed in any one of claims 1 to 5, characterized in that: The following steps are involved: When the antenna is reconstructed, liquid metal is injected into or exhausted from the liquid metal channel (201) in the liquid metal container (101) by injection or extrusion; When the liquid metal channel (201) is filled with liquid metal, the liquid metal is in full contact with the patch antenna radiator (102) and the metal floor (301), forming a back cavity slot antenna structure, and the antenna operates in a back cavity slot antenna mode; When the liquid metal is completely drained from the liquid metal channel (201), the patch antenna radiator (102) and the metal floor (301) cannot be closed by the liquid metal, and the antenna operates in a patch antenna mode.

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