Directional diagram reconfigurable liquid transparent antenna applied to ocean communication

Abstract

The invention provides a directional diagram reconfigurable liquid transparent antenna applied to ocean communication. The antenna is composed of a hexagonal star-shaped radiation cavity, an inverted L-shaped feed probe and a liquid ground. Through design and processing, besides a feed structure, the whole antenna realizes full transparency, has a good optical stealth effect, and has more application scenes. By utilizing the liquidity of liquid, distilled water is injected into different cavities, and the electric field distribution of the radiation cavity is changed, so that different patterns are generated. The antenna can realize a reconfigurable function of a directional diagram at 2.22-2.63 GHz, has five states of directional diagram switching modes, namely + / -15 degrees, + / -35 degrees and 0 degree, has better impedance matching and radiation directivity, and has a good optical stealth effect due to the transparent appearance.

Description

Technical Field

[0001] This invention belongs to the field of antenna technology, specifically a pattern-reconfigurable liquid transparent antenna for marine communications. Background Technology

[0002] Antennas are important radio frequency front-end components in microwave wireless power transmission, wireless communication and other fields. They are used to receive and radiate electromagnetic waves and realize the conversion between electromagnetic waves and guided waves.

[0003] With the rapid development of technology, the requirements for transmission rates and communication capacity in current communication systems are becoming increasingly stringent, necessitating that antennas possess the ability to cope with complex scenarios. The emergence of reconfigurable antennas allows for the transformation of antenna functions without altering the antenna structure.

[0004] Secondly, radiation pattern is a crucial indicator in antenna design. In today's complex communication environments, the ability to flexibly switch radiation directions is paramount. Pattern-reconfigurable antennas, which achieve directional changes without altering the antenna's structure, have become a hot research topic.

[0005] By loading distilled water, a transparent liquid antenna with a reconfigurable radiation pattern is created, giving the entire antenna a certain degree of stealth.

[0006] The paper "A Novel Pattern Reconfigurable Antenna Based On Liquid Metal" proposes a novel coaxial-fed reconfigurable antenna based on liquid metal. By injecting liquid metal into different shell layers, the antenna state can be switched, thereby exciting four radiation states: a +z-axis beam state, a conical omnidirectional beam state, and two directional beam states. Furthermore, the antenna structure is simple and does not require the assistance of other complex feed structures or parasitic structures.

[0007] The paper "A Radiation Pattern Reconfigurable Fabry–Pérot Antenna Based on Liquid Metal" proposes a novel beam-controllable Fabry-Pérot (FP) antenna employing a liquid metal partial reflective surface (PRS). The PRS can be divided into three distinct liquid metal-filled regions. By injecting liquid metal into specific regions, the antenna beam direction and 3 dB beamwidth can be controlled independently, providing a simple control method for FP antennas with reconfigurable radiation patterns.

[0008] The paper "Frequency and Pattern Reconfigurable Antenna Using Double Layer Petal Shaped Parasitic Structure" proposes a frequency and pattern reconfigurable antenna employing a double-layer petal-shaped parasitic structure loaded with PIN diodes. Its double-layer parasitic structure enables mode reconfigurability over a wider frequency range. The antenna's operating frequency is continuously tuned, and the radiation pattern is controllable, scanning from 0° to 360° in 25.7° increments.

[0009] Therefore, based on the above technical background and literature description, the purpose of this invention is to propose a pattern-reconfigurable liquid transparent antenna for marine communications. Summary of the Invention

[0010] Addressing the specific antenna requirements of wireless communication systems and microwave wireless power transfer, this invention aims to propose a pattern-reconfigurable liquid-transparent antenna for marine communications. This antenna employs a dual-layer structure, comprising a top hexagonal star-shaped radiating cavity, an inverted L-shaped feed probe, and a bottom water tray. The hexagonal star-shaped radiating cavity and the bottom water tray are connected by six transparent pillars. The inverted L-shaped feed probe passes through the bottom water tray and resides in the air layer between the hexagonal star-shaped radiating cavity and the bottom water tray. By injecting distilled water into different parts of the hexagonal star-shaped cavity, this antenna achieves pattern deflections of ±35°, ±15°, and 0°. Simultaneously, its high transparency provides a degree of stealth, making it valuable for research in marine communications.

[0011] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0012] To target the desired angle, a hexagonal star-shaped radiation cavity was designed, consisting of seven parts: a regular hexagonal radiation cavity and six equilateral triangular radiation cavities. By injecting water into different cavities to change the electric field, the radiation direction was switched.

[0013] Furthermore, a circular base is formed by filling the central cavity with distilled water, creating a water-filled base. Located 19mm from the top hexagonal star-shaped radiation cavity, it serves a reflective function.

[0014] Furthermore, the inverted L-shaped feed probe passes through the bottom water pan and is located in the air layer between the hexagonal star-shaped radiation cavity and the bottom water pan, serving as a radiation source.

[0015] The beneficial effects of the above-described solution in this invention are as follows:

[0016] Except for the feeding section, this invention achieves full transparency and also enables ±35°, ±15°, and 0° pattern deflection. This antenna has a novel structure, low cost, and advantages such as multiple radiation states, good radiation pattern directivity, high transparency, and good relative bandwidth. Attached Figure Description

[0017] Figure 1 This is the front view of an embodiment of the present invention.

[0018] Figure 2 This is a diagram of the hexagonal star-shaped radiation cavity structure in an embodiment of the present invention.

[0019] Figure 3 This is a diagram of the inverted L-shaped probe structure with power supply in an embodiment of the present invention.

[0020] Figure 4 These are reflection coefficient diagrams for antenna states 1 and 2 in this embodiment of the invention.

[0021] Figure 5 These are reflection coefficient diagrams for antenna states 3 and 5 in this embodiment of the invention.

[0022] Figure 6 This is a reflection coefficient diagram under antenna state 4 in this embodiment of the invention.

[0023] Figure 7 This is the radiation pattern of the antenna in state 1 at 2.4 GHz in this embodiment of the invention.

[0024] Figure 8 This is the radiation pattern of the antenna in state 2 at 2.4 GHz in this embodiment of the invention.

[0025] Figure 9 This is the radiation pattern of the antenna in state 3 at 2.4 GHz in this embodiment of the invention.

[0026] Figure 10 This is the radiation pattern of the antenna in state 4 at 2.4 GHz in this embodiment of the invention.

[0027] Figure 11 This is the radiation pattern of the antenna in state 5 at 2.4 GHz in this embodiment of the invention.

[0028] The diagram shows: 1. Front view structure; 2. Hexagonal star-shaped radiating cavity structure; 3. Feed inverted L-shaped probe structure; 4. Reflection coefficient diagrams for antenna states 1 and 2; 5. Reflection coefficient diagrams for antenna states 3 and 5; 6. Reflection coefficient diagram for antenna state 4; 7. Radiation pattern of antenna at 2.4 GHz in state 1; 8. Radiation pattern of antenna at 2.4 GHz in state 2; 9. Radiation pattern of antenna at 2.4 GHz in state 3; 10. Radiation pattern of antenna at 2.4 GHz in state 4; 11. Radiation pattern of antenna at 2.4 GHz in state 5. Detailed Implementation

[0029] The present invention will be further described in conjunction with the accompanying drawings and specific embodiments:

[0030] To clearly illustrate the technical solutions in the embodiments of the present invention, specific examples are provided below to illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0031] A pattern-reconfigurable liquid-transparent antenna for marine communications has been developed. The antenna employs a two-layer structure, comprising a top hexagonal star-shaped radiating cavity, an inverted L-shaped feed probe, and a bottom water tray. The hexagonal star-shaped radiating cavity and the bottom water tray are connected by six transparent pillars. The inverted L-shaped feed probe passes through the bottom water tray and resides in the air layer between the hexagonal star-shaped radiating cavity and the bottom water tray. This antenna achieves pattern deflections of ±35°, ±15°, and 0°. Simultaneously, its high transparency provides a degree of stealth, making it valuable for research in marine communications.

[0032] The top hexagonal star-shaped radiating cavity is divided into seven parts, consisting of a central regular hexagonal radiating cavity and six equilateral triangular radiating cavities. Asymmetric water injection into the triangular cavities disrupts the structural symmetry, leading to amplitude and phase imbalances in the orthogonal degenerate modes. Under ideal symmetry, the antenna only excites a single HEM. mold.

[0033] This allows for the switching of radiation patterns. The outer side of the regular hexagonal radiation cavity is 37mm long and 10mm high, while the inner side is 34.5mm long and 5.2mm high.

[0034] The inverted L-shaped feed structure is made of copper, passes through the bottom water tray, and reaches the air layer between the two layers. The vertical portion of the probe is 28 mm high, and the horizontal portion is 16 mm long. The feed position is selected at 46.25 mm from the center of the bottom water tray.

[0035] The chassis is formed by injecting distilled water. The chassis has an outer radius of 65mm, an inner cavity radius of 61mm, an outer height of 7mm, and an inner cavity height of 2.8mm. Water filling the cavity structure creates a reflective effect. Six cylinders support the upper and lower sections. The bottom radius of each cylinder is 3mm, and its height is 19mm. This 19mm also represents the height of the air layer between the top hexagonal radiation cavity and the bottom water tray.

[0036] The overall design makes the antenna more compact. Table 1 lists the relevant parameters of this invention.

[0037] Table 1. Parameters of a pattern-reconfigurable liquid transparent antenna

[0038] All relevant parameters of this invention are shown in Table 1.

[0039] Furthermore, when excited by the inverted L-shaped probe, the inverted L-shaped probe effectively excited the basic HEM. In this mode, the vertical portion of the probe couples energy into the fluid medium, while the horizontal extension provides the necessary magnetic coupling to establish a horizontal magnetic dipole equivalent current, ensuring the electric field vector is horizontally aligned within the cavity. This antenna achieves pattern deflections of ±35°, ±15°, and 0°.

[0040] Brief working principle of the invention:

[0041] To achieve the antenna pattern reconstruction function, distilled water is injected into different cavities of the hexagonal star-shaped radiating cavity, and an inverted L-shaped probe below the hexagonal star-shaped radiating cavity is used as a feed source.

[0042] The inverted L-shaped probe effectively excited the basic HEM. In this mode, the vertical portion of the probe couples energy into the medium liquid, while the horizontal extension provides the necessary magnetic coupling to establish a horizontal magnetic dipole equivalent current, so that the electric field vector is horizontally aligned in the cavity.

[0043] The deflection of the radiation pattern is mainly due to the disruption of structural symmetry caused by asymmetric water injection into the triangular cavity, leading to an imbalance in the amplitude and phase of the orthogonal degenerate modes. Under ideal symmetry, the antenna only excites a single HEM. mold.

[0044] HEM The mode is excited inside the antenna, equivalent to a horizontal magnetic dipole. The mirrored currents on the high-dielectric-constant liquid base are in the same direction. When the air layer height approaches zero, the source and mirrored magnetic currents directly superimpose, achieving maximum gain. Although the gain is higher when the air layer height is small, the hexagonal radiating cavity is tightly attached to the bottom water basin, confining the energy to the near field, resulting in an extremely narrow bandwidth and drastic changes in input impedance, leading to a complete deterioration of impedance matching, making it impossible to achieve 50 ohms. The proposed antenna has an air layer height of 19mm, retaining most of the gain and, more importantly, achieving good impedance matching. This represents an engineering compromise.

[0045] In laboratory settings, syringes are typically used for water injection to fill different cavities for convenience and efficiency. In industrial applications, a microfluidic pump control system can be considered to inject liquid into a hexagonal star-shaped radiating cavity, thereby achieving rapid filling of different cavities with liquid.

[0046] The injection fluid used is distilled water, which is colorless, odorless, environmentally friendly, and readily available. In this invention, the use of distilled water also ensures excellent light transmission for the entire antenna.

[0047] Liquid is injected into the bottom water tray, making the entire liquid water tray act as a high-dielectric reflector. When electromagnetic waves radiate downwards, they are effectively reflected upwards upon reaching the bottom liquid water tray, enhancing the energy in the main radiation direction and preventing energy leakage.

[0048] In laboratory settings, a syringe is used for convenient and quick liquid injection into the bottom liquid tray. In industrial applications, a microfluidic pump control system can also be considered to inject liquid into the bottom liquid tray. The bottom liquid tray only needs to be injected once.

[0049] Similarly, distilled water is the preferred choice for filling the liquid in the bottom liquid tray, which can also bring good results to the entire antenna application.

[0050] The bottom liquid water tray serves as a high-dielectric reflector to replace the metal ground, providing a new solution for fully transparent, all-dielectric antenna systems.

Claims

1. A pattern-reconfigurable liquid transparent antenna for marine communications, characterized in that: The antenna adopts a double-layer structure, the main body of which includes a top hexagonal star-shaped radiating cavity (2), an inverted L-shaped feed probe (3), and a bottom water tray (1). The hexagonal star-shaped radiating cavity (2) and the bottom water tray (1) are connected by six transparent pillars, and the inverted L-shaped feed probe (3) passes through the bottom water tray (1) and is located in the air layer between the hexagonal star-shaped radiating cavity (2) and the bottom water tray (1). This antenna achieves pattern deflection of ±35°, ±15°, and 0°. At the same time, the high transparency achieves a certain stealth effect, which has certain research value in marine communications.

2. The pattern-reconfigurable liquid transparent antenna for marine communication according to claim 1, characterized in that: The top hexagonal radiation cavity (2) is divided into seven parts, consisting of a central regular hexagonal radiation cavity (2) and six equilateral triangular radiation cavities (2). The radiation pattern is switched by injecting distilled water into different cavities. The outer side of the regular hexagonal radiation cavity is 37 mm long and the height is 10 mm, while the inner side is 34.5 mm long and the height is 5.2 mm.

3. A pattern-reconfigurable liquid transparent antenna for marine communication according to claim 1, characterized in that: The inverted L-shaped feed structure (3) is made of copper and passes through the bottom water tray (1) to reach the air layer between the two layers. The vertical part of the probe is 28 mm high and the horizontal part is 16 mm long. The power supply location should be 46.25mm from the center of the bottom water tray.

4. A pattern-reconfigurable liquid transparent antenna for marine communication according to claim 1, characterized in that: The chassis (1) is formed by injecting distilled water. The outer radius of the chassis is 65 mm, the inner radius is 61 mm, the height is 7 mm, and the inner cavity height is 2.8 mm. After water is injected into the cavity structure, a reflective effect is achieved.

5. A pattern-reconfigurable liquid transparent antenna for marine communication according to claim 1, characterized in that: Six cylinders support the upper and lower parts. The bottom radius of the cylinders is 3mm and the height is 19mm. At the same time, 19mm is also the height of the air layer between the top hexagonal star-shaped radiation cavity (2) and the bottom water plate (1).

6. A pattern-reconfigurable liquid transparent antenna for marine communication according to claim 1, characterized in that: Except for the power supply section, everything is made of transparent resin through 3D printing, achieving transparency and giving the entire antenna a certain degree of stealth effect.

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