Multi-band filter array antenna

Abstract

The present invention relates to a multi-band filter array antenna. It comprises: a single-layer structure of localized surface plasmons (LSPs) and surface wave transmission gratings, and an antenna patch assembly; the LSPs are polygonal, with first dielectric units arranged along the sides of the polygon; the number of surface wave transmission gratings corresponds to the number of first dielectric units, with second dielectric units arranged along a single side of the long side of the surface wave transmission grating, with each second dielectric unit positioned opposite a first dielectric unit; the number of antenna patch assemblies is one less than the number of surface wave transmission gratings; the ports of each surface wave transmission grating are extended and connected to each antenna patch assembly, and the ports of the surface wave transmission gratings not connected to the antenna patch assembly serve as output ports. The present invention combines the LSPs and surface wave transmission gratings as a multi-band filter, which is then connected to the antenna patch assembly to form a multi-band filter array antenna, capable of obtaining the required multi-frequency signals at the output end.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a multi-band filtering array antenna. Background Art

[0002] With the advancement of wireless communication technology, the demand for device miniaturization and integration is increasing. Microcommunication networks (MCNs), as an advanced wireless communication technology, play an important role in multiple key areas, such as wireless sensing, health monitoring, extracorporeal communication, and navigation. The successful implementation of these applications depends largely on the effective integration of wireless technology into microdevices. Antennas and filters play a crucial role in these devices. They not only transmit wireless signals but also protect the devices from interference from external signals and ensure normal operation within the target frequency band.

[0003] Traditional technologies typically use separate antenna and filter designs, but this type of design is no longer able to meet the needs of modern applications. To address this issue, filter antennas have been proposed that integrate the functions of antennas and filters into a single component.

[0004] Currently, large-scale and in-depth research on filter antennas has been conducted both domestically and internationally. For example, in the field of dual-band filter antennas, there are antennas that achieve compact 5G millimeter-wave applications by using two repeated square resonators and a T-shaped feeder; switchable dual-band filter antennas and reconfigurable tri-polarization filter antennas implemented using T-shaped wire piles and PIN diodes; and flexible energy-autonomous filter antennas and wearable dual-band filter monopole antennas designed for ethanol detection and wireless communications. However, most of these designs and research use multi-layer structures or require complex feed networks. Summary of the Invention

[0005] Based on this, it is necessary to provide a multi-band filter array antenna with a low profile, single-layer structure and a simple feeding network to address the above technical problems.

[0006] A multi-band filtering array antenna, comprising: a localized surface plasma, a surface wave transmission grating and an antenna patch assembly;

[0007] The localized surface plasmon and the surface wave transmission grating are a single-layer structure;

[0008] The LSPM is polygonal, and the first dielectric unit is arranged along the side length of the polygon;

[0009] The number of the surface wave transmission gratings corresponds to the number of the first dielectric units, and a second dielectric unit is provided on one side of the long side of the surface wave transmission grating, and each second dielectric unit is positioned opposite to each first dielectric unit;

[0010] The number of the antenna patch components is one less than the number of the surface wave transmission gratings; the ports of each surface wave transmission grating are extended and connected to each antenna patch component respectively, and the ports of the surface wave transmission gratings that are not connected to the antenna patch components are used as output ends.

[0011] In one embodiment, the first dielectric unit includes a plurality of dielectric sheets; the dielectric sheets are arranged periodically and vertically inwardly along the sides of the polygon to form comb-shaped first periodic grooves.

[0012] In one embodiment, the first periodic grooves include a middle section, a left section, and a right section; the periodic grooves of the middle section have the same vertical inward extension height, the periodic grooves of the left section have a vertical inward extension height that gradually increases from the left end toward the middle section, and the periodic grooves of the right section have a vertical inward extension height that gradually increases from the right end toward the middle section.

[0013] In one embodiment, the periodic grooves of the left section and the periodic grooves of the right section have the same structure and are symmetrically arranged.

[0014] In one embodiment, the second dielectric unit includes a plurality of dielectric sheets; the dielectric sheets are arranged along the long side of the surface wave transmission grating at periodic intervals vertically inward on one side to form a comb-shaped second periodic groove.

[0015] In one embodiment, the second periodic grooves include a transmission section and a transition section; the periodic grooves of the transmission section have the same vertically inward extension height; the periodic grooves of the transition section have a vertically inward extension height that gradually increases from the port toward the transmission section, and are flush with the periodic groove height of the transmission section on the side close to the transmission section.

[0016] In one embodiment, the number of periodic grooves in the transmission segment is greater than or equal to the number of the first periodic grooves.

[0017] In one embodiment, the first periodic grooves and the second periodic grooves have the same width.

[0018] In one embodiment, the LS plasmon is an equilateral triangle.

[0019] In one embodiment, the antenna patch assembly includes a first antenna patch and a dielectric substrate that are stacked, wherein the first antenna patch located above is smaller than the dielectric substrate located below; and the port of the surface wave transmission grating is connected to the first antenna patch.

[0020] Compared with the existing technology, the multi-band filter array antenna provided by the present invention has the following effects:

[0021] 1. The multi-band filter array antenna proposed in this invention breaks through the design concept of traditional multi-layer filter antennas. By designing the localized surface plasmon and surface wave transmission grating into a single-layer structure with a low profile, the compact structure can significantly reduce the overall thickness and weight of the antenna. It is highly adaptable to antenna integration and application scenarios, and is particularly suitable for devices with high miniaturization and integration requirements.

[0022] 2. The single-layer structure design can reduce the interaction between layers, thereby effectively reducing these parasitic effects and improving the performance stability of the antenna.

[0023] 3. The number of first dielectric units can be flexibly adjusted based on demand, along with a corresponding number of second dielectric units. This approach improves the antenna's frequency band selectivity, enabling the formation of multiple localized surface wave resonant modes, thereby creating multiple frequency passbands and ultimately obtaining the desired multi-frequency signal. Furthermore, the antenna's operating frequency range is extended, adapting to a wider range of communication standards and application requirements.

[0024] 4. The multi-band filter array antenna feeding network proposed in the present invention is simple and can reduce signal loss. It can be more easily integrated with other systems or modules. In addition, it can achieve better matching and avoid reflection loss and standing wave problems caused by poor matching. It not only reduces design and manufacturing costs, but also facilitates subsequent debugging and maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0026] Figure 1 A schematic diagram of the structure of a multi-band filter array antenna in one embodiment;

[0027] Figure 2 A schematic diagram of a localized surface plasmon structure in one embodiment;

[0028] Figure 3 A schematic diagram of a surface wave transmission grating structure in one embodiment;

[0029] Figure 4 FIG. 1 is a schematic diagram of a simulated electric field distribution of a multi-band filter on an xoy plane in an embodiment; wherein, Figure 4 (a) is a schematic diagram of the simulated electric field distribution at a frequency of 2.45 GHz. Figure 4(b) is a schematic diagram of the simulated electric field distribution at a frequency of 4.45 GHz. Figure 4 (c) Schematic diagram of the simulated electric field distribution at 5 GHz frequency;

[0030] Figure 5 A schematic diagram of simulated S-parameters of a multi-band filter in one embodiment;

[0031] Figure 6 Schematic diagram of S11 parameter changes obtained through simulation of a single patch antenna assembly, a multi-band filter array antenna, and a multi-band filter array antenna on a human body in one embodiment;

[0032] Figure 7 A schematic diagram of actual gains obtained through simulation of a single patch antenna assembly, a multi-band filter array antenna, and a multi-band filter array antenna on a human body in one embodiment;

[0033] Figure 8 Schematic diagram of the simulated electric field distribution of a multi-band filter array antenna on the xoy plane in one embodiment; wherein, Figure 8 (a) is a schematic diagram of the simulated electric field distribution at a frequency of 2.45 GHz. Figure 8 (b) is a schematic diagram of the simulated electric field distribution at a frequency of 4.45 GHz. Figure 8 (c) Schematic diagram of the simulated electric field distribution at 5 GHz frequency;

[0034] Figure 9 A schematic diagram of actual S11 parameter changes obtained by measuring a single patch antenna assembly, a multi-band filter array antenna, and a multi-band filter array antenna on a human body in one embodiment;

[0035] Figure 10 FIG. 1 is a schematic diagram of simulation and measurement radiation of a multi-band filter array antenna in one embodiment; wherein, Figure 10 (a) is at 2.45GHz frequency, Schematic diagram of simulation and measurement radiation when Figure 10 (b) is at 2.45GHz frequency, Schematic diagram of simulation and measurement radiation when Figure 10 (c) is at 4.45GHz frequency, Schematic diagram of simulation and measurement radiation when Figure 10 (d) is at 4.45GHz frequency, Schematic diagram of simulation and measurement radiation when Figure 10 (e) is at 5 GHz frequency, Schematic diagram of simulation and measurement radiation when Figure 10 (f) is at 5GHz frequency, Schematic diagram of simulation and measurement radiation when ;

[0036] Figure 11 The actual gain measured for a single patch antenna assembly and a multi-band filter array antenna in one embodiment.

[0037] Description of reference numerals:

[0038] LSP 11, first dielectric unit 111, dielectric sheet 112, first periodic groove 113, middle section 114, left section 115, right section 116, surface wave transmission grating 22, second dielectric unit 221, port 222, second periodic groove 223, transmission section 224, transition section 225, antenna patch assembly 33, first antenna patch 331, dielectric substrate 332.

[0039] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to 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 intended to limit the present invention.

[0041] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0042] In addition, the terms "first," "second," and so on, used in this disclosure are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being described. Thus, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this disclosure, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0043] In the present invention, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; it can mean mechanical connection, electrical connection, physical connection, or wireless communication connection; it can mean direct connection or indirect connection through an intermediate medium; it can mean internal communication between two elements or interaction between two elements, unless otherwise specified. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] The following describes the embodiments of the present invention in detail with reference to the accompanying drawings.

[0045] See Figures 1 to 3 , shows a multi-band filtering array antenna according to an embodiment of the present invention, comprising: a localized surface plasmon (LSP) 11, a surface wave (SW) grating (22), and an antenna patch assembly (33). The LSP 11 and SW grating (22) are single-layer structures. The LSP 11 is polygonal, with first dielectric elements (111) arranged along the sides of the polygon. The number of SW gratings (22) corresponds to the number of first dielectric elements (111). A second dielectric element (221) is arranged along a single side of the long side of the SW grating (22), with each second dielectric element (221) positioned opposite a first dielectric element (111). The number of antenna patch assemblies (33) is one less than the number of SW gratings (22). The ports (222) of each SW grating (22) are extended and connected to respective antenna patch assemblies (33), and the ports (222) of the SW gratings (22) not connected to the antenna patch assemblies (33) serve as output ports.

[0046] It can be understood that the filtering antenna can achieve selective transmission of signals of specific frequencies while suppressing unnecessary signals, thereby enhancing the anti-interference ability of the device.

[0047] The present invention combines LSPM 11 with a surface wave transmission grating 22 to form a multi-band filter. The multi-band filter is then connected to an antenna patch assembly 33 to form a multi-band filter array antenna. Surface waves are transmitted through the second dielectric element 221 on the surface wave transmission grating 22. These surface waves occasionally interact with the first dielectric element 111 on the LSPM 11, forming multiple localized surface wave resonant modes and thus multiple frequency passbands. It can be seen that the number of first dielectric elements 111 can be flexibly set according to requirements, and second dielectric elements 221 can be set accordingly to the number of first dielectric elements 111 to achieve transmission of the required number of specific frequency signals. Ultimately, the desired multi-frequency signals are obtained at the output, while signals other than those required are filtered out.

[0048] Furthermore, the present invention breaks through the traditional design thinking of multi-layer filtering antennas. By designing the localized surface plasma and surface wave transmission grating as a single-layer structure with a low profile, the multi-band filter formed is also a single-layer structure. Its compact structure can significantly reduce the overall thickness and weight of the antenna, and is highly adaptable to antenna integration and application scenarios. It is particularly suitable for devices with high miniaturization and integration requirements, such as wearable devices. Due to its compact design, thin thickness, and light weight, it can provide greater design flexibility for wearable devices, thereby making wearable devices lighter and more comfortable while maintaining efficient wireless communication capabilities, providing new possibilities for the development of future wearable devices. In addition, the design of the single-layer structure can reduce the interaction between layers, thereby effectively reducing these parasitic effects and improving the performance stability of the antenna.

[0049] It is worth noting that, for ease of understanding, this embodiment Figures 1 to 3 The multi-band filter array antenna shown in the figure is specifically a three-bandpass multi-band filter array antenna. The present invention will specifically illustrate the scheme with a three-bandpass multi-band filter array antenna, but it does not constitute a specific limitation on the multi-band filter array antenna proposed in the present invention. It can also be set as a four-bandpass, five-bandpass, or even more-bandpass filter array structure according to needs. The number of passbands is related to the cutoff frequency of the localized surface plasmon unit structure. By designing the localized surface plasmon unit structure, the corresponding number of frequency band signals can be obtained. The specific structural principles are the same and will not be elaborated in detail later.

[0050] Specifically, see Figure 1 , which is a schematic diagram of a multi-band filter array antenna structure. To obtain a tri-band signal, the localized surface plasmon 11 is configured in a triangular shape, with first dielectric units 111 disposed along each of the three sides of the triangle. Three surface wave transmission gratings 22 are provided based on the number of first dielectric units 111. The surface wave transmission gratings 22 are elongated rectangular structures, with second dielectric units 221 disposed on one side of the long side of the surface wave transmission grating 22. The three second dielectric units 221 are positioned opposite the three first dielectric units 111. The number of antenna patch assemblies 33 is one less than the number of surface wave transmission gratings 22, i.e., two antenna patch assemblies 33 are provided. The ports 222 of the two surface wave transmission gratings 22 are extended and connected to the antenna patch assemblies 33, respectively. The port 222 of the surface wave transmission grating 22 not connected to the antenna patch assembly 33 is used as the output port.

[0051] See Figure 2, a schematic diagram of the LSP structure. The LSP 11 is an equilateral triangle. First dielectric units 111 are positioned on each of the three long sides of the triangle. These first dielectric units 111 comprise a plurality of dielectric sheets 112. These sheets 112 are periodically spaced vertically inward along the sides of the triangle to form comb-like first periodic grooves 113. These first periodic grooves 113 comprise a middle section 114, a left section 115, and a right section 116. The periodic grooves in the middle section 114 extend vertically inward to the same height, while the height of the periodic grooves in the left section 115 gradually increases from the left end toward the middle section 114. The height of the periodic grooves in the right section 116 gradually increases from the right end toward the middle section 114. Specifically, the number of periodic grooves in the left section 115 and the number of periodic grooves in the right section 116 are equal and symmetrically arranged.

[0052] It is worth noting that the dimensions of each part of the localized surface plasmon 11 can be adjusted. For example, the height of the periodic grooves in the middle section 114, the left section 115, and the right section 116 can be adjusted separately or simultaneously to meet the corresponding frequency band, number of passbands, adjustment of resonant modes, and impedance matching requirements. The number of dielectric plates 112 in the middle section 114, the left section 115, and the right section 116 can also be increased or decreased to form different numbers of periodic grooves to meet the corresponding localized resonant mode to surface wave propagation mode conversion requirements. Generally, the periodic grooves in the left section 115 and the right section 116 have the same structure and are symmetrical. The three corners of the equilateral triangle can be set to have a cross-section with a width of t1. By adjusting the width of t1, different adjustment resonant mode requirements can be met.

[0053] See Figure 3 , is a schematic diagram of the surface wave transmission grating structure. The surface wave transmission grating 22 is a long rectangular structure with a second dielectric unit 221 disposed on one side of the long side. The second dielectric unit 221 also includes a plurality of dielectric sheets 112. During arrangement, dielectric sheets 112 are periodically spaced vertically inward along the long side of the surface wave transmission grating 22 to form a comb-shaped second periodic groove 223. The second periodic groove includes a transmission section 224 and a transition section 225. The periodic grooves of the transmission section 224 extend vertically inward to the same height. The periodic grooves of the transition section 225 extend vertically inward to a height that gradually increases from the port 222 toward the transmission section 224 and is flush with the height of the periodic grooves of the transmission section 224 on the side close to the transmission section 224. The number of periodic grooves in the transmission section 224 is greater than or equal to the number of the first periodic grooves 113, so as to be compatible with the first periodic grooves 113.

[0054] Furthermore, the dielectric sheets 112 in the first dielectric unit 111 and the second dielectric unit 221 are periodically spaced and arranged at equal intervals, so that the first periodic grooves 113 and the second periodic grooves 223 have the same width. When the second dielectric unit 221 is positioned opposite the first dielectric unit 111, the openings of the first periodic grooves 113 and the openings of the second periodic grooves 223 are positioned opposite each other. This allows the first periodic grooves 113 and the second periodic grooves 223 to interact with each other during surface wave transmission, thereby exciting a resonant mode (i.e., a resonance mode).

[0055] The port 222 is the remaining width W3 on the short side of the long rectangular structure after the second dielectric unit 221 is provided on the surface wave transmission grating 22 . The port 222 with the width W3 is extended and connected to the antenna patch assembly.

[0056] It is worth noting that the dimensions of various components of the surface wave transmission grating 22 can be adjusted. For example, the heights of the periodic grooves in the transmission section 224 and the transition section 225 can be adjusted separately or simultaneously to accommodate different transmission frequency requirements. The number of dielectric plates 112 in the transmission section 224 and the transition section 225 can also be increased or decreased to form different numbers of periodic grooves to meet the conversion requirements of the local resonant mode and surface wave, as well as the impedance matching requirements between the surface wave transmission and the output port. Furthermore, the width W3 of the port 222 can also be adjusted to meet the corresponding impedance matching requirements. The localized surface plasmon 11 and the surface wave transmission grating 22 are preferably made of metal.

[0057] The antenna patch assembly 33 includes a stacked first antenna patch 331 and a dielectric substrate 332. The upper first antenna patch 331 is smaller than the lower dielectric substrate 332. Port 222 of the surface wave transmission grating 22 is connected to the first antenna patch 331. During connection, a notch with a depth of L4 and a width of W3 is defined on one side of the first antenna patch 331. Port 222 extends into the notch and connects to the first antenna patch 331. The first antenna patch 331 is a rectangular patch antenna, preferably made of metal. It has a low profile, a simple structure, and is easily compatible with PCMS. The dielectric substrate preferably has a dielectric constant of 2.2, a loss factor of 0.0009, and a thickness of 1.524 mm. The back of the dielectric substrate is a plain metal patch.

[0058] During use, the dimensions of the various components of the LSPS 11 and the surface wave transmission grating 22 are adjusted based on the frequency of the signal to be transmitted, and then connected to the antenna patch assembly 33. The antenna patch assembly 33 receives the radiated waves and converts them into surface waves within the two surface wave transmission gratings 22. The surface waves interact with the three first dielectric elements 111 in the triangular LSPS 11, exciting three resonant modes and forming three frequency passbands, ultimately resulting in a three-frequency signal at the output. In this way, a three-bandpass multi-band filter array antenna is implemented to filter out other interfering signals and capture only the three-frequency signals that need to be transmitted.

[0059] Similarly, when a quad-frequency signal needs to be obtained, the LSPC 11 can be set to a quadrilateral; when a multi-frequency signal needs to be obtained, the LSPC 11 can be set to a polygon, and then the surface wave transmission grating 22 and the antenna patch assembly 33 can be set accordingly.

[0060] In one of the embodiments, in order to verify the superiority of the multi-band filter array antenna proposed in the present invention, a three-bandpass multi-band filter array antenna structure is still used. By designing the dimensions of each component and based on the application scenario of the wearable communication system, simulation and experimental measurements are performed on the transmission frequencies of 2.45 GHz, 4.45 GHz and 5 GHz.

[0061] First, the multi-band filter formed by the combination of the localized surface plasmon 11 and the surface wave transmission grating 22 is modeled according to the pre-designed dimensions, and then a simulation is performed. The simulated electric field distribution obtained by the simulation is as follows: Figure 4 As shown in the figure, E Z represents the electric field intensity of the xoy plane along the z-axis direction; the results show that this method can effectively excite three artificial localized surface plasmon resonance modes, propagate surface waves, and perform three types of out-of-band suppression.

[0062] See Figure 5 , is a schematic diagram of simulated S-parameters for a multi-band filter. This multi-band filter is a three-bandpass multi-band filter. It can be seen that the three-bandpass multi-band filter designed in the present invention exhibits relatively good parameters at all three frequencies. Therefore, the three-bandpass multi-band filter designed in this embodiment can meet the design requirements of a three-bandpass multi-band filter array antenna.

[0063] After the three-bandpass multi-band filter meets the design requirements, a patch antenna assembly is selected, and the three-bandpass multi-band filter is connected to the antenna patch assembly 33 to form a three-bandpass multi-band filter array antenna. Then, a single patch antenna assembly, a three-bandpass multi-band filter array antenna, and a three-bandpass multi-band filter array antenna set on the human body are modeled and then simulated and verified. The S11 parameter changes obtained by simulation are as follows: Figure 6As shown in Figure 2, the simulation results show that there are three frequencies of resonance in the system.

[0064] In addition, the real gain of the multi-band filter array antenna is also a very important parameter. Therefore, in this embodiment, the real gain of three cases, a single patch antenna component, a three-band pass multi-band filter array antenna, and a three-band pass multi-band filter array antenna set on the human body, is simulated in the frequency range of 2 GHz to 5.5 GHz. The simulation results are as follows: Figure 7 As shown in the figure, the simulated actual gains of the triple-bandpass multi-band filter array antenna at the 2.45 GHz, 4.45 GHz, and 5 GHz resonant frequencies are 5.7 dBi, 6.27 dBi, and 8.49 dBi, respectively. Furthermore, there are three sharp passbands with values ​​greater than 0 dBi in the 2.38 GHz to 2.58 GHz, 4.3 GHz to 4.47 GHz, and 4.7 GHz to 5.3 GHz frequency bands.

[0065] When the three-bandpass multi-band filter array antenna is placed on the plane interface between air and human tissue (εr=50), the simulated electric field on the xoy plane is as follows: Figure 8 As shown in the figure, E Z represents the electric field intensity in the xoy plane along the z-axis. The results show that the triple resonant localized surface plasmon modes can be effectively excited, resulting in triple out-of-band suppression.

[0066] When the simulation results of the three-bandpass multi-band filter array antenna meet the requirements, the actual product is processed according to the dimensions obtained by simulation, and a series of experiments and tests are carried out. When the actual product is processed, printed circuit board technology is used, and the multi-band filter array antenna is made of F4B material. The S parameter measurement is designed by vector network analysis, such as Figure 9 Figure 1 shows the actual S11 parameter variation obtained by measuring a single patch antenna assembly, a multi-band filter array antenna, and a multi-band filter array antenna on a human body. Compared to a single patch antenna assembly, the multi-band filter array antenna has excellent S11 < -10 dB filtering performance at 2.45 GHz, 4.45 GHz, and 5 GHz. Except for 5 GHz, the filter bands in the measurement are similar to Figure 6 The difference is mainly attributed to the higher LSPR mode loss.

[0067] Furthermore, the measurement in the dark room and Normalized radiation pattern of a plane. Figure 10 , Figure 10 (a) Figure 10 (b) with Figure 10(c) shows the schematic diagrams of simulated and measured radiation at 2.45 GHz, 4.45 GHz, and 5 GHz frequencies, respectively. represents the yz plane, represents the xy plane. Although there are some errors due to additional cable loss, high modal loss, and measurement errors, the measured results are basically consistent with the simulation results. They have almost the same number of main lobes and side lobes. and The measurement results show that the triple-bandpass multi-band filter array antenna provides a wide angular coverage for signal transmission in the application scenarios of health monitoring and wearable communication systems. Figure 11 The measured achieved gains of a single patch antenna assembly and a triple-bandpass multi-band filter array antenna are shown, which agree well with the simulation results. Compared to the achieved gain of a single patch antenna, the proposed multi-band filter array antenna exhibits better out-of-band rejection within the desired frequency band.

[0068] In summary, the triple-bandpass multi-band filter array antenna in this embodiment achieves true gains of 5.53 dBi, 5.12 dBi, and 4.95 dBi at the 2.45 GHz, 4.45 GHz, and 5 GHz resonant frequencies, respectively. Furthermore, three sharp passbands with values ​​greater than 0 dBi exist in the 2.38 GHz to 2.53 GHz, 4.38 GHz to 4.5 GHz, and 4.63 GHz to 5.12 GHz bands. Test results demonstrate that this design exhibits excellent filtering performance, with three sharp passbands and high target out-of-band suppression, meeting the requirements for a triple-bandpass multi-band filter array antenna.

[0069] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The above-described embodiments merely illustrate several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that a person skilled in the art would be able to make numerous modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A multi-band filtering array antenna, characterized in that: include: Localized surface plasmon, surface wave transmission grating and antenna patch components; The localized surface plasmon and the surface wave transmission grating are a single-layer structure; The LSPC is polygonal, and the first dielectric unit is arranged along the side length of the polygon; The number of the surface wave transmission gratings corresponds to the number of the first dielectric units, and a second dielectric unit is provided on one side of the long side of the surface wave transmission grating, and each second dielectric unit is positioned opposite to each first dielectric unit; The number of the antenna patch components is one less than the number of the surface wave transmission gratings; the ports of each surface wave transmission grating are extended and connected to each antenna patch component respectively, and the ports of the surface wave transmission gratings that are not connected to the antenna patch components are used as output ends.

2. The multi-band filtering array antenna according to claim 1, wherein: The first dielectric unit includes a plurality of dielectric sheets; The dielectric sheets are periodically spaced vertically inwardly along the sides of the polygon to form first periodic grooves in a comb-like shape.

3. The multi-band filtering array antenna according to claim 2, wherein: The first periodic groove includes a middle section, a left section and a right section; The periodic grooves of the middle section extend vertically inwardly to the same height, the periodic grooves of the left section extend vertically inwardly to gradually increase in height from the left end to the middle section, and the periodic grooves of the right section extend vertically inwardly to gradually increase in height from the right end to the middle section.

4. The multi-band filtering array antenna according to claim 3, wherein: The periodic grooves of the left section and the periodic grooves of the right section have the same structure and are symmetrically arranged.

5. The multi-band filtering array antenna according to claim 1, wherein: The second dielectric unit includes a plurality of dielectric sheets; The dielectric sheets are periodically arranged vertically inwardly along the long side of the surface wave transmission grating on one side to form a comb-shaped second periodic groove.

6. The multi-band filtering array antenna according to claim 5, characterized in that: The second periodic groove includes a transmission section and a transition section; The periodic grooves of the transmission section extend vertically inwards at the same height; The vertically inwardly extending height of the periodic grooves of the transition section gradually increases from the port toward the transmission section, and is flush with the height of the periodic grooves of the transmission section on the side close to the transmission section.

7. The multi-band filtering array antenna according to claim 6, characterized in that: The number of the periodic grooves in the transmission section is greater than or equal to the number of the first periodic grooves.

8. The multi-band filtering array antenna according to any one of claims 2 to 7, characterized in that: The first periodic grooves and the second periodic grooves have the same width.

9. The multi-band filtering array antenna according to claim 1, wherein: The localized surface plasmon is an equilateral triangle.

10. The multi-band filtering array antenna according to claim 1, wherein: The antenna patch assembly includes a first antenna patch and a dielectric substrate that are stacked, wherein the first antenna patch located on the upper side is smaller than the dielectric substrate located on the lower side; A port of the surface wave transmission grating is connected to the first antenna patch.

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