CPW feed high-gain transparent flexible antenna

Abstract

The utility model belongs to the technical field of antennas, and relates to a CPW feed high-gain transparent flexible antenna, which comprises a reflecting plate and an antenna body, the reflecting plate is positioned at a position 10mm right below the antenna body, the antenna body comprises a substrate and antenna units, and the four antenna units are orthogonally placed on the substrate. The grounding planes of the four antenna units are interconnected through a decoupling structure at the center of the antenna to form a common grounding plane, and the common grounding plane has a transparent and flexible structure and can be bent at an angle of 200 degrees, so that the common grounding plane is suitable for various applications, especially in the field of Internet of Things; a multi-input multi-output system is adopted, the working frequency range is 2.16-20 GHz, the wireless communication performance is improved, the highest efficiency can reach 51%, the peak gain is improved to 4 dBi by adopting a reflecting plate, and meanwhile, the antenna has diversity gain exceeding 9.988 dB and a low envelope correlation coefficient lower than 0.05.

Description

Technical Field

[0001] The utility model belongs to the technical field of antennas, and relates to a CPW-fed high-gain transparent flexible antenna. Background Technique

[0002] With the development of the new generation of communication technologies, the Internet of Things (IoT) has gained great momentum and changed the way we interact with the world. IoT technology relies to a large extent on the efficient data exchange between countless devices, so a powerful wireless communication solution is required. In this context, multiple-input multiple-output (MIMO) antennas play a key role. MIMO antennas enhance IoT data exchange by simultaneously transmitting and receiving data through multiple antennas, ensuring reliable and high-speed connections.

[0003] Ultra-wideband MIMO antennas perform excellently in the field of IoT. Ultra-wideband technology provides higher data rates, improved signal quality and reduced interference, and is very suitable for precise positioning services, asset tracking and smart homes. Their adaptability to various frequencies and wider bandwidths can meet the needs of various IoT devices, making them indispensable.

[0004] In addition, with the continuous diversification of IoT applications, the demand for transparent and flexible ultra-wideband MIMO antennas is increasing. These antennas can be seamlessly integrated into various surfaces, including glass, plastic and fabric. This adaptability is crucial for IoT applications such as wearable devices, smart packaging and even smart windows, where aesthetics, flexibility and transparency are essential. The future of IoT largely depends on the integration of transparent, flexible ultra-wideband MIMO antennas to provide ubiquitous, efficient and unobtrusive connections in an increasingly interconnected world.

[0005] Some MIMO antennas with flexible or transparent characteristics have been proposed. The dual-port MIMO antenna using a polyimide film substrate proposed in the literature "S. Virothu and M. Satya Anuradha, "Flexible CP diversity antenna for 5G cellular Vehicle-to-Everything applications," AEU-International Journal of Electronics and Communications, vol. 152, p. 154248, Jul. 2022." has a working frequency band of 3.23 - 6.26 GHz and can be applied to the 5G field; the literature "A. Desai, J. Kulkarni, M. M. Kamruzzaman, H. "H.T. Hsu, and A.A. Ibrahim, ""Interconnected CPW Fed Flexible 4-Port MIMO Antenna for UWB, X, and Ku Band Applications,"" IEEE Access, vol. 10, pp. 57641-57654, 2022" proposed a four-port MIMO antenna using a flexible FR-4 substrate, which can cover the ultra-wideband, X, and Ku bands; the two-port MIMO antenna using a soda-lime glass substrate proposed in the literature ""M.G.Nabi Alsath, P.D.Sowjanya, S.Kirubaveni, and n.Indu V, ""Optically Transparent MIMO Antenna with Polarisation Diversity for Vehicular Communications,"" International Journal of Electronics, pp. 1-17, 2023"" has a transparency of 72% and can provide a frequency band of 3.1-12 GHz, which can be used for automotive communications; in the literature ""K.K. So, B.J. Chen, and C.H. Chan, ""Microwave and Millimeter-Wave MIMO Antenna Using Conductive ITO Film,"" IEEE Access, vol. 8, pp. 207024-207033, 2020"", the four-port MIMO antenna using a glass substrate achieved an antenna transparency of 84%, and its operating frequency range is 4.9 GHz and 26 GHz, which is suitable for the field of 5G mobile intelligent communications; the literature ""A. Desai, M. Palandoken, J. Kulkarni, G. Byun, and T.K. Nguyen, ""Wideband Flexible / Transparent Connected-Ground MIMO Antennas for Sub-6 GHz 5G and WLAN Applications,"" IEEE Access, vol. 9, pp. 147003-147015, 2021"" introduced a four-port MIMO antenna using a Melinex substrate, with a frequency range of 2.2-6 GHz and an antenna transparency of 70%, suitable for Sub-6 5G and WLAN applications. Therefore, there is a need for transparent flexible ultra-wideband MIMO antennas with good isolation in the Internet of Things field at present, but there has been no report so far.However, these existing antennas do not meet the requirements of the Internet of Things (IoT) field. Therefore, there is an urgent need for a CPW-fed high-gain transparent flexible antenna to provide a transparent flexible ultra-wideband MIMO antenna with good isolation in the IoT field. Summary of the Invention

[0006] The purpose of the present invention is to overcome the shortcomings of the existing technology and design a CPW-fed high-gain transparent flexible antenna.

[0007] To achieve the above purpose, the CPW-fed high-gain transparent flexible antenna of the present invention includes a reflector and an antenna body. The reflector is located 10 mm directly below the antenna body. The antenna body includes a substrate and antenna elements. Four antenna elements are orthogonally placed on the substrate, and the ground planes of the four antenna elements are interconnected through a decoupling structure at the center of the antenna to form a common ground plane.

[0008] As a further technical solution of the present invention, the reflector uses a square ITO-PET reflector with a side length of 70 mm.

[0009] As a further technical solution of the present invention, the electrical size of the antenna body is 0.38λ0 × 0.38λ0, where λ0 represents the free space wavelength at 2.2 GHz.

[0010] As a further technical solution of the present invention, the substrate uses a PET film with a thickness of 0.125 mm. The length and width of the substrate are both 52 mm, and its relative dielectric constant ε r is 3.2, and the tangent loss tanδ is 0.022.

[0011] As a further technical solution of the present invention, the antenna element uses an ultra-wideband antenna. The conductive material of the ultra-wideband antenna is ITO material with a thickness of 0.01 mm, and the surface resistance is 5 Ω / sq.

[0012] As a further technical solution of the present invention, the antenna element includes a wire head, a wiring, a wire root, and an antenna ground plane; the wiring is in a gourd shape, and both ends of the wiring are connected to the wire head and the wire root respectively. The antenna ground plane is in a window structure, and four windows are opened on the antenna ground plane. The antenna ground plane is symmetrically arranged on both sides of the wiring and the wire root.

[0013] Compared with the existing technology, the present invention has the following beneficial effects:

[0014] (1) It has a transparent and flexible structure, with a transparency as high as 71.1%, and can be bent at an angle of 200°, making it suitable for various applications, especially in the Internet of Things (IoT) field;

[0015] (2) Adopt a multiple-input multiple-output (MIMO) system with a working frequency range of 2.16 to 20 GHz, which can improve wireless communication performance;

[0016] (3) The maximum efficiency of this antenna can reach 51%, and a reflector is adopted, which can increase the peak gain to 4 dBi. At the same time, it has a diversity gain (DG) of more than 9.988 dB and a low envelope correlation coefficient (ECC) of less than 0.05. Description of the Drawings

[0017] Figure 1 It is a structural diagram of the CPW-fed high-gain transparent flexible antenna described in the present invention.

[0018] Figure 2 It is a structural diagram of the antenna body described in the present invention.

[0019] Figure 3 It is a physical application diagram of the CPW-fed high-gain transparent flexible antenna described in the present invention.

[0020] Figure 4 It is the S-parameter simulation and measurement curve of the CPW-fed high-gain transparent flexible antenna described in the present invention.

[0021] Figure 5 It is the simulation and measurement results of the radiation efficiency and peak gain of the CPW-fed high-gain transparent flexible antenna described in the present invention.

[0022] Figure 6 It is the simulated and measured far-field radiation patterns of the CPW-fed high-gain transparent flexible antenna described in the present invention at 3 GHz, 10 GHz, and 18 GHz in the x-z and y-z planes. Detailed Embodiments

[0023] The present invention will be further described below through embodiments in conjunction with the drawings.

[0024] Embodiment 1:

[0025] As Figure 1 and Figure 2As shown in the figure, this embodiment provides a CPW-fed high-gain transparent flexible antenna, which includes a reflector 1 and an antenna body. The reflector 1 is located 10 mm directly below the antenna body. The antenna body includes a substrate 2 and antenna elements 3. Four antenna elements 3 are orthogonally placed on the substrate 2. The ground planes of the four antenna elements 3 are interconnected through a decoupling structure at the center of the antenna to form a common ground plane. The antenna element includes a wire head 31, a wire connection 32, a wire root 33, and an antenna ground plane 34. The wire connection 32 is in a gourd shape. The two ends of the wire connection 32 are respectively connected to the wire head 31 and the wire root 33. The antenna ground plane 34 is in a window structure. Four windows are opened on the antenna ground plane 34. The antenna ground plane 34 is symmetrically arranged on both sides of the wire connection 32 and the wire root 33.

[0026] Specifically, the reflector 1 is a square ITO-PET reflector with a side length of 70 mm.

[0027] Specifically, the electrical size of the antenna body is 0.38λ0×0.38λ0, where λ0 represents the free-space wavelength at 2.2 GHz.

[0028] Specifically, the substrate 2 is a PET film with a thickness of 0.125 mm. The length and width of the substrate 2 are both 52 mm, and its relative dielectric constant ε r is 3.2, and the tangent loss tanδ is 0.022.

[0029] Specifically, the antenna element 3 is a ultra-wideband antenna. The conductive material of the ultra-wideband antenna is ITO (indium tin oxide) material with a thickness of 0.01 mm, and the surface resistance is 5 Ω / sq.

[0030] As Figure 3 shown, when the CPW-fed high-gain transparent flexible antenna in this embodiment is in use, external connectors are installed on the four antenna elements, and the entire antenna is installed on the using device through the external connectors.

[0031] Embodiment 2:

[0032] This embodiment conducts a simulation test experiment on the CPW-fed high-gain transparent flexible antenna described in Embodiment 1. The results are as Figures 4 - 6 shown. As Figure 4 shown, in the simulation and measurement, S11 remains below -10 dB in the range of 2.16 - 20 GHz; in the measurement, it is below -10 dB in the range of 2 - 20 GHz. The simulated and measured values of S21, S31, and S41 are all below -20 dB in the entire operating frequency range, indicating significant element isolation, and the measurement results are in good agreement with the simulation results; Figure 5 It shows that the peak radiation efficiency of the antenna is 51%. The measured gain varies between -10.0 dBi and 4 dBi in the operating frequency range. Compared with other antennas using ITO materials, the gain is significantly improved; inFigure 6 Among them, one port of the antenna is excited, and the remaining ports are terminated with 50-ohm loads. The measurement results of the far-field radiation are in good agreement with the simulation results.

[0033] The above content is a further detailed description of the present utility model in combination with specific embodiments. It cannot be determined that the specific implementation of the present utility model is only limited to these descriptions. For those of ordinary skill in the technical field to which the present utility model belongs, without departing from the concept of the present utility model, several simple deductions or substitutions can still be made, and all should be regarded as belonging to the protection scope determined by the claims submitted for the present utility model.

Claims

1. A CPW-fed high-gain transparent flexible antenna, characterized in that: It includes a reflector and an antenna body. The reflector is located 10 mm below the antenna body. The antenna body includes a substrate and an antenna unit. Four antenna units are orthogonally placed on the substrate. The ground planes of the four antenna units are interconnected through a decoupling structure at the center of the antenna to form a common ground plane.

2. The CPW-fed high-gain transparent flexible antenna according to claim 1, characterized in that: The reflective plate is a square ITO-PET reflective plate with a side length of 70 mm.

3. The CPW-fed high-gain transparent flexible antenna according to claim 1, characterized in that: The electrical dimensions of the antenna body are 0.38λ0×0.38λ0, where λ0 represents the free space wavelength of 2.2 GHz.

4. The CPW-fed high-gain transparent flexible antenna according to claim 1, characterized in that: The substrate is a 0.125 mm thick PET film, the length and width of the substrate are both 52 mm, and its relative dielectric constant ε r is 3.2, and the tangent loss tanδ is 0.

022.

5. The CPW-fed high-gain transparent flexible antenna according to claim 1, characterized in that: The antenna unit adopts an ultra-wideband antenna, the conductive material of which is an ITO material with a thickness of 0.01 mm and a surface resistance of 5Ω / sq.

6. The CPW-fed high-gain transparent flexible antenna according to claim 1, characterized in that: The antenna unit includes a wire end, a wiring connection, a wire root and an antenna grounding plate; the wiring connection is a gourd-shaped structure, and the two ends of the wiring connection are respectively connected to the wire end and the wire root; the antenna grounding plate is a window structure, and four windows are opened on the antenna grounding plate. The antenna grounding plate is symmetrically arranged on both sides of the wiring connection and the wire root.

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