Wideband low-coupling parasitic radiation microstrip antenna applied to wireless sensing of Internet of Things

Abstract

The invention relates to the field of wireless data transmission antennas of the Internet of Things, in particular to a broadband low-coupling parasitic radiation microstrip antenna for wireless sensing application of the Internet of Things, which comprises an upper-layer dielectric substrate and a lower-layer dielectric substrate, and the upper-layer dielectric substrate and the lower-layer dielectric substrate are tightly attached to each other. Three circular feed via holes are distributed in the lower layer dielectric substrate, the lower surface of the lower layer dielectric substrate is covered with the metal grounding plate, three circular holes and a rectangular gap are formed in the metal grounding plate, the circle centers of the three circular holes in the metal grounding plate coincide with the circle centers of the three circular feed via holes in the lower layer dielectric substrate, and the rectangular gap is formed between the three circular holes in the metal grounding plate and the circular feed via holes in the lower layer dielectric substrate. The radiuses of the three circular holes in the metal grounding plate are larger than the radiuses of the three circular feed via holes, the upper surface of the lower dielectric substrate is provided with three rectangular metal patches, and the three rectangular metal patches are respectively orthogonal to the three rectangular gaps in the grounding plate. And the centers of the three circular feed through holes are respectively positioned on the middle lines of the long sides of the three rectangular metal patches. The upper surface of the upper-layer dielectric substrate is provided with six separated arc-shaped metal parasitic radiation units, and the upper surface of the upper-layer dielectric substrate is provided with three groups of circular metal columns. High-isolation broadband resonance and multi-unit cooperative work antenna equipment is realized through slot feeding, a separation arc parasitic patch radiation technology, a space diversity technology and a three-group metal column isolation technology.

Description

Technical Field

[0001] The present invention relates to the field of intelligent network wireless data transmission antennas, and in particular to a broadband low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications. Background Art

[0002] The Internet of Things (IoT), or "the Internet of Everything," is considered the next wave of the information industry following computers and the Internet, and a crucial component of the next generation of information technology. The IoT combines various information sensing devices with networks to form a vast network, enabling real-time interconnection, information exchange, and intelligent services among people, machines, and objects. The interconnection of everything is another major revolution in human science and technology, breaking the temporal and spatial constraints of human control over various resources.

[0003] Artificial intelligence technologies, represented by DeepSeek and ChapGTP, have experienced rapid development, garnering widespread attention and rapidly integrating with numerous industries. The deep integration of AI and IoT systems is bringing intelligence to every aspect of these systems, forming a new type of intelligent internet of things (IoT). In the AI ​​era, countless IoT devices will need to be capable of autonomous decision-making and distributed execution, representing a new type of terminal intelligence. However, the foundation of intelligent decision-making relies on big data analysis, meaning that intelligent terminal devices must communicate big data with the cloud in a timely manner. High-quality antenna equipment is essential for high-speed big data transmission and is crucial for future intelligent terminals to make informed decisions. In IoT systems, multimodal information collection will continue to play a crucial role, and antenna equipment with excellent signal coverage and data carrying capacity is crucial to the overall performance of IoT systems. Currently, antennas used in IoT wireless communication systems are single antennas, such as stand-alone sub-antennas or single-patch radiating planar antennas, which cannot meet the requirements for high-speed data transmission. In the coming IoT era, high-performance antennas capable of carrying multimodal, high-capacity data transmission are needed to adapt to the complex and changing signal requirements of the IoT environment, improve interoperability between intelligent terminals, and ensure accurate and real-time big data analysis within these terminals.

[0004] Disadvantages of existing technologies: (1) Antenna devices in the IoT information collection system all use a single antenna for data transmission. Single-antenna structure devices cannot achieve large data transmission and cannot adapt to the IoT system's demand for real-time transmission of large data. (2) When deploying a multi-unit antenna structure in a limited space, the energy coupling between the antenna ports of each unit is very serious, resulting in large signal interference and low transmission efficiency, making it difficult to achieve high-speed transmission of large data. As a result, the unit antennas in the device system cannot work normally independently. (3) Although the antenna devices that currently realize wireless transmission of collected data in the IoT system have a wide signal coverage, the resonant bandwidth of the single sub-antenna is relatively narrow. This type of narrowband antenna device cannot meet the IoT's requirements for large data transmission. Summary of the Invention

[0005] In order to overcome the shortcomings of antenna equipment in existing Internet of Things information collection systems that cannot achieve high-speed data transmission in a timely manner, the present invention designs a broadband, low-coupling parasitic radiation microstrip antenna for intelligent Internet of Things wireless sensing applications. This antenna device can well solve the problems of narrow antenna bandwidth, small number of antenna units, and severe coupling between multiple antennas in the existing technology.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: a broadband low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications, comprising an upper dielectric substrate and a lower dielectric substrate, the upper dielectric substrate and the lower dielectric substrate being tightly fitted together, three circular feed vias distributed in the lower dielectric substrate, the lower surface of the lower dielectric substrate being covered with a metal ground plate, the metal ground plate having three circular holes and a rectangular gap, the three circular holes in the metal ground plate coinciding with the centers of the three circular feed vias in the lower dielectric substrate, the radius of the three circular holes in the metal ground plate being greater than the radius of the three circular feed vias, three rectangular metal patches on the upper surface of the lower dielectric substrate, the three rectangular metal patches being orthogonal to the three rectangular gaps in the ground plate, the centers of the three circular feed vias being located on the midlines of the long sides of the three rectangular metal patches, six separate arc-shaped metal parasitic radiation units being provided on the upper surface of the upper dielectric substrate, and three groups of circular metal columns being provided on the upper surface of the upper dielectric substrate.

[0007] Preferably, the upper dielectric substrate and the lower dielectric substrate are made of the same material, have the same thickness, width and height, and are both made of polytetrafluoroethylene FR4 with a dielectric constant of 4.4 and a loss tangent of 0.02.

[0008] Preferably, the metal patch ground plate is closely attached to the lower surface of the lower dielectric substrate, has the same length and width as the lower surface of the lower dielectric substrate, and is relatively thin. The metal ground plate is made of copper or silver to enhance conductivity and ensure signal transmission efficiency.

[0009] Preferably, the six separated arc-shaped metal patches are located on the upper surface of the upper dielectric substrate, the center of the circle formed by the inner and outer arc edges of the six separated arc-shaped metal patches coincides with the center of the upper dielectric substrate, and the six separated arc-shaped metal patches form six arc-shaped gaps with exactly the same width in the radial direction.

[0010] Preferably, the three groups of identical metal posts are located in three arc-shaped gaps formed by six separate arc-shaped metal patches, with two separate arc-shaped metal patches between each two groups of metal posts. The metal posts have a diameter of 1-3 mm, a height of 2-8 cm, and a number of 4-10, evenly spaced, and all located within the gaps. These metal posts effectively suppress coupling between the gaps, improve isolation, and ensure stable and independent operation of the unit antenna structure.

[0011] Preferably, the metal pillars are made of highly conductive material with a smooth surface to reduce signal loss. The bottom of each metal pillar is tightly bonded to the upper dielectric substrate.

[0012] Preferably, the three circular vias in the lower dielectric substrate, the three circular non-metallic areas in the metal ground plate that are cocentric with the vias and have a radius greater than the radius of the vias, the three rectangular non-metallic patches in the metal ground plate, and the three rectangular metal patches on the upper surface of the lower dielectric substrate together constitute three completely identical feeding structures.

[0013] Preferably, the feeding structure is composed of a circular non-metallic area in the metal ground plate, a rectangular non-metallic gap in the ground plate, a circular via hole and a rectangular metal patch.

[0014] Preferably, the three rectangular metal patches on the upper surface of the lower dielectric substrate are respectively parallel to the gaps formed by the six separated arc-shaped parasitic metal patches, and there is a group of circular metal columns between every two rectangular metal patches.

[0015] Preferably, the three circular vias in the lower dielectric substrate are located on the midline of the long axes of the three rectangular metal patches and away from the center of the upper surface of the lower dielectric substrate. The diameter of the circular vias is 1~2 mm to ensure that the core signal line of the SMA connector is electrically connected to the metal patch.

[0016] Preferably, the radius of the three circular non-metallic areas in the metal ground plate is 3-5 mm, and the centers of the circles coincide with the centers of the via holes.

[0017] Preferably, the long sides of the three rectangular non-metallic areas in the metal ground plate are respectively perpendicular to the long sides of the three rectangular metal patches on the upper surface of the lower dielectric substrate, and are perpendicular to the gaps formed by the six separated arc-shaped metal patches, and are close to the center of the metal ground plate.

[0018] Preferably, the metal patches are made of copper or silver, and all the metal patches on the dielectric substrate are processed using circuit board etching technology. The circuit board etching technology ensures high precision of the metal patches, a smooth surface, and reduces signal interference.

[0019] The present invention provides a broadband, low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications. It has the following beneficial effects:

[0020] This invention achieves broadband resonance through slot feeding and separated arc-shaped parasitic patch radiation technology. The effective radiation absolute bandwidth is 2.01 GHz (4.93 GHz to 6.94 GHz), and the relative bandwidth reaches 33.9%, making it a broadband radiating antenna. Broadband antennas are more suitable for high-speed data transmission.

[0021] This invention utilizes spatial diversity technology and a shared dielectric substrate and ground plane to deploy three independently fed element antennas within a relatively small planar space, creating a three-element microstrip antenna device. This multi-element antenna is more capable of supporting high-speed, multimodal data transmission.

[0022] By placing three sets of metal columns within the gaps formed by three separate curved metal patches, this invention effectively suppresses the coupling of radiated energy between the antenna elements, improving the isolation between the three antenna elements. This ultimately led to the design of the antenna being declared a three-element, low-coupling, parasitic radiation microstrip antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The figure is a perspective structural diagram illustrating an antenna device according to the present invention.

[0024] Figure 2 The figure is a schematic top view of the structure of the antenna device of the present invention according to the content of the invention.

[0025] Figure 3 The figure is a schematic diagram of the back structure of the antenna device of the present invention according to the invention content.

[0026] Figure 4 The curves of port parameters varying with frequency obtained by numerical analysis of the finite element method for the antenna device designed for the present invention are shown in Figure 1. Curve a shows the variation of the port reflection coefficient with frequency, and curve b shows the variation of the coupling system between different ports with frequency.

[0027] Figure 5 The frequency obtained by numerical calculation and analysis of the finite element method for the antenna device designed for the present invention f = 5.45 GHz, phi is the long-range radiation gain curve of the unit antenna in the range of 0 to 360°.

[0028] Figure markings: 10-metal ground plate, 11-bottom dielectric substrate, 12-upper dielectric substrate, 13-first arc-shaped metal patch, 14-second arc-shaped metal patch, 15-third arc-shaped metal patch, 16-fourth arc-shaped metal patch, 17-fifth arc-shaped metal patch, 18-sixth arc-shaped metal patch, 19-first group of metal cylinders, 20-second group of metal cylinders, 21 third group of metal cylinders, 22-first circular non-metallic patch, 23-first rectangular metal patch, 24-first circular via, 25-first rectangular non-metallic patch, 26-second rectangular non-metallic patch, 27-second rectangular metal patch, 28-second circular via, 29-second non-metallic circular patch, 30-third rectangular non-metallic patch, 31-third metal patch, 32-third circular non-metallic patch, 33-third circular via. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the specification of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0030] Example:

[0031] Please see the attached Figure 1-3 The embodiment of the present invention provides a broadband low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications, including an upper dielectric substrate 12 and a lower dielectric substrate 11. The upper dielectric substrate 12 and the lower dielectric substrate 11 are tightly attached to each other. The upper dielectric substrate 12 and the lower dielectric substrate 11 are made of the same material and have the same thickness, width and height. The specific dimensions can be, but are not limited to, length L = 80±2% mm, width W = 80±2% mm, thickness h = 1.6±1% mm, and are both made of polytetrafluoroethylene FR4 with a dielectric constant of 4.4 and a loss tangent of 0.02. Metal patch structures are processed on the upper surface of the upper dielectric substrate 12 and the upper and lower surfaces of the lower dielectric substrate 11 using circuit board printing technology. A metal ground plate 10 is fixedly connected to the bottom of the lower dielectric substrate 11. The material of the metal ground plate 10 can be, but is not limited to, copper or silver. The specific dimensions of the metal ground plate 10 are length L = 80 ± 2% mm, width W= 80 ± 2% mm. Metal ground plane 10 contains three circular holes 22, 29, and 32, each with a radius of 1.2 ± 1% mm and a height of h = 1.6 ± 1% mm. The centers of circular holes 22, 29, and 32 are 23 ± 2% mm from the center of the metal ground plane. Metal ground plane 10 also contains rectangular slots 25, 26, and 30, each with a length of 16 ± 2% mm and a width of 2 ± 1% mm. The geometric centers of slots 25, 26, and 30 are 16.6 ± 2% mm from the center of metal ground plane 10. The three circular non-metallic areas 22, 29, and 32 in metal ground plane 10 have a radius of 2 ± 1% mm and their geometric centers are also 23 ± 2% mm from the center of the metal ground plane. Three rectangular metal patches 23, 27, and 31 are processed on the upper surface of the lower dielectric substrate 11 to serve as the feed signal lines of the three units of the antenna of the present invention. The length is 22±2% mm and the width is 2±1% mm. The inner short sides of the three rectangular metal patches 23, 27, and 31 are 10±2% mm away from the geometric center of the upper surface of the lower dielectric substrate 11.

[0032] The upper surface of the upper dielectric substrate 12 is machined with six separate curved metal patches 13, 14, 15, 16, 17, and 18. The inner radius is 5.6 ± 1% mm, and the outer radius is 32 ± 2% mm. There are gaps of 3 ± 1% mm between adjacent curved metal patches, forming a total of six gaps of equal width. Feed structures are deployed beneath three of these gaps, while three groups of metal pillars 19, 20, and 21 are arranged in the remaining three gaps. Each group of metal pillars consists of eight, with spacing between adjacent pillars of 3 ± 1% mm. The innermost pillar is 5.8 ± 2% mm from the geometric center of the upper surface of the upper dielectric substrate 12. Each pillar has a radius of 0.3 ± 1% mm and a height of 10 ± 2% mm.

[0033] When testing the antenna designed in this invention, an SMA connector is soldered. The SMA connector's metal core is connected to the rectangular microstrip signal lines 23, 27, and 31 through the circular vias in the lower dielectric substrate. The SMA connector's outer grounding metal structure is then connected to the metal ground plate 10 on the back of the lower dielectric substrate 11. Testing is then ready. The SMA connector is a commonly used connector for microwave device testing and will not be described in detail here.

[0034] 4-5, the three-dimensional electromagnetic simulation software HFSS is used to simulate and analyze the broadband low-coupling parasitic radiation microstrip antenna designed for intelligent network wireless sensing applications. It is found that the port reflection coefficient of the antenna is less than -10 dB in the 4.93 ~ 6.84 GHz band, the relative bandwidth is 33.9%, and the absolute bandwidth is 2.01 GHz. In the entire resonant frequency band, the port isolation Sij (i≠j) is less than -15dB, which can well meet practical requirements. That is, the present invention relates to a broadband high-isolation resonant antenna device. At the same time, f = 5.48 GHz frequency, theta = 26°, the far-field radiation gain is 4.04 dBi, demonstrating that the antenna designed in this invention is a high-gain antenna device. In summary, the invented antenna device can well meet the needs of high-capacity, multi-source data wireless transmission in the complex environments of the future intelligent network.

[0035] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A broadband low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications, comprising an upper dielectric substrate (12) and a lower dielectric substrate (11), characterized in that: The upper dielectric substrate (12) and the lower dielectric substrate (11) are tightly fitted together, three circular feed holes (24, 28, 33) are distributed in the lower dielectric substrate (11), the lower surface of the lower dielectric substrate (11) is covered with a metal grounding plate (10), the metal grounding plate (10) has three circular holes (22, 29, 32) and rectangular gaps (25, 26, 30), the three circular holes (22, 29, 32) in the metal grounding plate (10) and the three circular feed holes (24, 28, 33) in the lower dielectric substrate (11) have a central axis. The three circular holes (22, 29, 32) in the metal grounding plate (10) have radii greater than the radii of the three circular feed holes (24, 28, 33). The upper surface of the lower dielectric substrate (11) has three rectangular metal patches (23, 27, 31). The three rectangular metal patches (23, 27, 31) are respectively orthogonal to the three rectangular gaps (25, 26, 30) in the grounding plate (10). The centers of the three circular feed holes (24, 28, 33) are respectively located on the midlines of the long sides of the three rectangular metal patches (23, 27, 31). The upper surface of the upper dielectric substrate (12) is provided with six separated arc-shaped metal parasitic radiation units (13, 14, 15, 16, 17, 18). The upper surface of the upper dielectric substrate (12) is provided with three groups of circular metal columns (19, 20, 21).

2. The broadband low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications according to claim 1, characterized in that: The upper dielectric substrate (12) and the lower dielectric substrate (11) are made of the same material, have the same thickness, width and height, and are both made of polytetrafluoroethylene FR4 with a dielectric constant of 4.4 and a loss tangent of 0.

02.

3. The broadband low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications according to claim 1, characterized in that: The metal patch ground plate (10) is closely attached to the lower surface of the lower dielectric substrate (11), and has the same length and width as the lower surface of the lower dielectric substrate (11). The metal ground plate (10) is relatively thin. The metal ground plate (10) is made of copper or silver to enhance electrical conductivity and ensure signal transmission efficiency.

4. The broadband low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications according to claim 1, characterized in that: The six separated arc-shaped metal patches (13, 14, 15, 16, 17, 18) are located on the upper surface of the upper dielectric substrate (12); the center of the circle formed by the inner and outer arc edges of the six separated arc-shaped metal patches (13, 14, 15, 16, 17, 18) coincides with the center of the upper dielectric substrate (12); and the six separated arc-shaped metal patches (13, 14, 15, 16, 17, 18) form six arc-shaped gaps with exactly the same width in the radial direction.

5. The broadband low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications according to claim 1, characterized in that: The three groups of identical metal columns (19, 20, 21) are respectively located in three arc-shaped gaps formed by six separated arc-shaped metal patches (13, 14, 15, 16, 17, 18). There are two separated arc-shaped metal patches (13, 14, 15, 16, 17, 18) between each two groups of metal columns (19, 20, 21). The metal columns (19, 20, 21) have a diameter of 1 to 3 mm, a height of 2 to 8 cm, and a number of 4 to 10. They are evenly spaced and all located within the gaps. The metal columns (19, 20, 21) effectively suppress coupling between gaps, improve isolation, and ensure that the unit antenna structure operates stably and independently. The metal columns (19, 20, 21) are made of highly conductive material and have a smooth surface, which reduces signal loss. The bottom of each metal column (19, 20, 21) is tightly bonded to the upper dielectric substrate (12).

6. The broadband low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications according to claim 1, characterized in that: The three circular vias (24, 28, 33) in the lower dielectric substrate (11), the three circular non-metallic areas (22, 29, 32) in the metal grounding plate (10) that are co-centered with the vias and have a radius greater than the via radius, the three rectangular non-metallic patches (25, 26, 30) in the metal grounding plate (10), and the three rectangular metal patches (23, 27, 31) on the upper surface of the lower dielectric substrate (11) together constitute three identical feeding structures. The one feeding structure is composed of a circular non-metallic area (22, 29, 32) in the metal grounding plate (10), a rectangular non-metallic gap (25, 26, 30) in the grounding plate (10), a circular via (24, 28, 33), and a rectangular metal patch (23, 27, 31).

7. The broadband low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications according to claim 1, characterized in that: The three rectangular metal patches (23, 27, 31) on the upper surface of the lower dielectric substrate (11) are respectively parallel to the gaps formed by the six separated arc-shaped parasitic metal patches (13, 14, 15, 16, 17, 18), and a group of circular metal columns (19, 20, 21) are provided between every two rectangular metal patches (23, 27, 31).

8. The broadband low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications according to claim 1, characterized in that: The three circular vias (24, 28, 33) in the lower dielectric substrate (11) are located on the long axis center lines of the three rectangular metal patches (23, 27, 31) and away from the center of the upper surface of the lower dielectric substrate (11). The diameters of the circular vias (24, 28, 33) are 1-2 mm. In order to ensure that the core signal line of the SMA connector is electrically connected to the metal patches, the radius of the three circular non-metallic areas (22, 29, 32) in the metal ground plate (10) is 3-5 mm, and the centers of the circles coincide with the centers of the vias (24, 28, 33).

9. The broadband low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications according to claim 1, characterized in that: The long sides (25, 26, 30) of the three rectangular non-metallic areas in the metal grounding plate (10) are respectively perpendicular to the long sides of the three rectangular metal patches (23, 27, 31) on the upper surface of the lower dielectric substrate (11), and are also perpendicular to the gaps formed by the six separated arc-shaped metal patches (13, 14, 15, 16, 17, 18), and are close to the center of the metal grounding plate (10).

10. The broadband low-coupling parasitic radiation microstrip antenna for intelligent network wireless sensing applications according to claim 1, characterized in that: The metal patches (13, 14, 15, 16, 17, 18, 23, 27, 31) are all made of copper or silver. The metal patches (13, 14, 15, 16, 17, 18, 23, 27, 31) on the surfaces of the dielectric substrates (11, 12) are all processed using circuit board etching technology. The circuit board etching technology ensures high precision of the metal patches, a smooth surface, and reduces signal interference.

Images