An antenna and communication device

Abstract

The application discloses an antenna and a communication device, the antenna comprises upper and lower conductors which do not directly contact and have the same extension direction, the upper conductor comprises a radiation section and a resonant patch in sequence along the extension direction; the lower conductor comprises multiple second substructures which are separated in sequence along the extension direction, the radiation section at the first end of the upper conductor and the second substructure at the first end of the lower conductor are connected with the center feeding line and the ground of the feeding coaxial line respectively, the feeding coaxial line feeds the upper and lower conductors, and electromagnetic waves are emitted outward through the upper and lower conductors to realize the omnidirectional broadband radiation characteristic. The application retains the broadband characteristic of the leaky wave antenna and maintains the advantages of high efficiency and high radiation efficiency of the resonant antenna, and realizes the WLAN double-frequency broadband omnidirectional full coverage.

Description

Technical Field

[0001] This invention belongs to the field of wireless communication technology, and particularly relates to an antenna and a communication device. Background Technology

[0002] Wireless local area networks (WLANs) have diverse service scenarios and are widely used in indoor or outdoor environments. To achieve point-to-multipoint communication, antennas with omnidirectional radiation capabilities are required. For home router applications, the IEEE 802.11ax protocol (WiFi 6) specifies two operating frequency bands for WLAN: 2.4 GHz (2.4-2.484 GHz) and 5 GHz (5.15-5.835 GHz). Although traditional dipole arrays can achieve omnidirectional radiation, they suffer from narrowband limitations, only supporting applications in the 2.4 GHz band and unable to cover the 5 GHz band, nor can they support dual-band WLAN applications.

[0003] Classical leaky wave antennas typically have a whip-like shape and, as traveling wave antennas, possess broadband characteristics. However, they suffer from difficulties in miniaturization, lower-than-standard wide-side radiation effects, and generally cannot achieve omnidirectional radiation. Furthermore, leaky wave antennas based on strongly dispersive waveguide designs struggle to maintain stable beam pointing over a wide frequency range. Summary of the Invention

[0004] Purpose of the invention: One purpose of this invention is to provide an antenna with omnidirectional broadband radiation characteristics that can operate in both 2.4G and 5G dual-band frequencies.

[0005] Another object of the present invention is to provide a communication device.

[0006] Technical solution: The antenna of the present invention includes an upper conductor and a lower conductor that extend in the same direction but do not directly contact each other. The upper conductor includes a radiating segment and a resonant patch in sequence along the extension direction. The lower conductor includes a plurality of spaced-apart second substructures in sequence along the extension direction. The radiating segment at the first end of the upper conductor and the second substructure at the first end of the lower conductor are respectively connected to the center feed line of the feeding coaxial line and ground. The feeding coaxial line feeds the upper conductor and the lower conductor, and electromagnetic waves are emitted outward through the upper conductor and the lower conductor to achieve omnidirectional broadband radiation characteristics.

[0007] Optionally, the radiating segment can be a strip.

[0008] Optionally, the radiating section includes a feeding section and a modulation period, the modulation period including a plurality of periodic first substructures arranged sequentially along the extension direction, each first substructure including a comb line and a strip line.

[0009] Optionally, the periodic structure length of the multiple periodic first substructures is p, p = 1 / 4λ ~ λ, and the spacing width between adjacent second substructures of the lower conductor is d, d = 1 / 4λ ~ λ, and p > d, where λ is the wavelength corresponding to the operating frequency band of the antenna.

[0010] Optionally, the upper conductor and the lower conductor are separated by a dielectric substrate or an air layer.

[0011] Optionally, the length of the radiating segment is l, where l = 3 / 4λ to 3λ, and λ is the wavelength corresponding to the operating frequency band of the antenna.

[0012] Optionally, the multiple second substructures of the lower conductor are directly separated by air or electrically connected by narrow wires, and the spacing between adjacent second substructures of the lower conductor is d, where d = 1 / 4λ ~ λ, and λ is the wavelength corresponding to the operating frequency band of the antenna.

[0013] Optionally, the antenna can operate in the 2.4 GHz and 5 GHz frequency bands.

[0014] Optionally, the feed segment at the first end of the upper conductor includes a microstrip line with a trapezoidal size for connection to the feed coaxial line.

[0015] The present invention also provides a communication device, including a radio frequency circuit and the antenna, wherein the radio frequency circuit is used for communication using the antenna.

[0016] Beneficial effects: Compared with the prior art, the significant technical effects of this invention are as follows: In the 2.4G band, the antenna is in a pure resonant mode; in the 5G band, since the comb line supports artificial surface plasmon slow waves and the stripline supports quasi-TEM waves, there is a mode mismatch between the two. According to the mode modulation leaky wave theory, the periodic design of the mode mismatch will excite higher-order spatial harmonics. When the modulation period is designed to meet the condition that the spatial harmonics are fast waves, the guided wave can radiate outward in the form of a leaky wave. At the same time, the resonant patch also radiates to the wide side, consistent with the leaky wave radiation, further enhancing the antenna's radiation performance in the wide side direction. As a special LWA, the antenna combines the advantages of broadband, miniaturization, and high efficiency by utilizing hybrid leaky wave and resonant operation; the application of the mode modulation leaky wave method enables the proposed LWA to achieve effective wide-side radiation. Attached Figure Description

[0017] Figure 1 This is an exploded view of the antenna provided in an embodiment of the present invention;

[0018] Figure 2 This is a schematic diagram of the right-side structure of the antenna provided in an embodiment of the present invention;

[0019] Figure 3 A top view of the antenna structure provided in an embodiment of the present invention;

[0020] Figure 4 This is a bottom view schematic diagram of the antenna structure provided in an embodiment of the present invention;

[0021] Figure 5 Antenna pattern in the 2.4 GHz band provided for embodiments of the present invention;

[0022] Figure 6 Antenna pattern in the 5G band provided in this embodiment of the invention;

[0023] Figure 7 An exploded view of the antenna provided in a preferred embodiment of the present invention;

[0024] Figure 8 This is a right-side view of the antenna structure provided in a preferred embodiment of the present invention;

[0025] Figure 9 This is a top view of the antenna structure provided in a preferred embodiment of the present invention;

[0026] Figure 10 This is a bottom view schematic diagram of the antenna structure provided in a preferred embodiment of the present invention;

[0027] Figure 11 This is a top view of the antenna modulation period structure provided in a preferred embodiment of the present invention;

[0028] Figure 12 Antenna pattern in the 2.4 GHz band provided for a preferred embodiment of the present invention;

[0029] Figure 13 The antenna pattern in the 5G band provided in a preferred embodiment of the present invention;

[0030] Figure 14 This is a schematic diagram illustrating an application scenario of the preferred embodiment of the present invention as a home router antenna;

[0031] Figure 15 for Figure 14 The S-parameter curve of the home router antenna is shown below.

[0032] Figure 16 for Figure 14 The three-dimensional radiation patterns of the home router antenna are shown in the simulation and measurement; where (a) is the simulated three-dimensional radiation pattern of the 2.4G band, (b) is the simulated three-dimensional radiation pattern of the 5G band, (c) is the measured three-dimensional radiation pattern of the 2.4G band, and (d) is the measured three-dimensional radiation pattern of the 5G band.

[0033] Figure 17 for Figure 14The two-dimensional radiation diagrams of the home router antenna in the 2.4 GHz band are shown in the simulation and measurement; where (a) is the measured two-dimensional radiation diagram and (b) is the simulated two-dimensional radiation diagram.

[0034] Figure 18 for Figure 14 The diagram shows the simulated and measured two-dimensional radiation patterns of a home router antenna in the 5G band; where (a) is the two-dimensional radiation pattern of the 5.15GHz e-plane, (b) is the measured two-dimensional radiation pattern of the 5.5GHz e-plane, (c) is the simulated two-dimensional radiation pattern of the 5.85GHz e-plane, (d) is the two-dimensional radiation pattern of the 5.15GHz h-plane, (e) is the measured two-dimensional radiation pattern of the 5.5GHz h-plane, and (f) is the measured two-dimensional radiation pattern of the 5.85GHz h-plane.

[0035] Figure 19 for Figure 14 The diagram shows the antenna efficiency of a home router, based on both simulation and measurement.

[0036] In the diagram: 100 - upper conductor; 300 - lower conductor; 110 - stripline; 101 - feed segment; 102 - combline; 103 - stripline; 104 - resonant patch; 301 - narrow wire; 110 - first substructure; 310 - second substructure; 400 - metal ground plane; 1 - first feed coaxial line; 2 - second feed coaxial line. Detailed Implementation

[0037] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0038] To facilitate understanding, the application scenarios of the antennas involved in the embodiments of this invention will first be explained. The antennas provided in the embodiments of this invention are suitable for 2.4G and 5G dual-band router applications, especially in home routers. The antennas involved in the embodiments of this invention can be used as access point antennas and can be connected to radio frequency circuits via feed lines.

[0039] The antenna of this invention includes an upper conductor and a lower conductor that extend in the same direction but are not in direct contact. The upper conductor includes a radiating segment and a resonant patch sequentially along its extension direction. The lower conductor includes multiple spaced-apart second substructures sequentially along its extension direction. The radiating segment at the first end of the upper conductor and the second substructure at the first end of the lower conductor are respectively connected to the center feed line of the feed coaxial line and ground. The feed coaxial line feeds the upper and lower conductors, and electromagnetic waves are emitted outward through the upper and lower conductors to achieve omnidirectional broadband radiation characteristics. The radiating segment is a stripline or includes a feed segment and a modulation period. The modulation period includes multiple periodic first substructures arranged sequentially along the extension direction, and each first substructure includes a comb line and a stripline.

[0040] The length of the radiating section is l, where l = 3 / 4λ ~ 3λ, and λ is the wavelength corresponding to the operating frequency band of the antenna.

[0041] First refer to Figures 1 to 4 , Figure 1 This is an exploded view of the antenna provided in an embodiment of the present invention. Figures 2 to 4 The diagrams show the right-view, top-view, and bottom-view structural schematics of the antenna provided in the embodiments of the present invention. (Combined with...) Figures 1 to 4 As shown, the antenna provided in this embodiment of the invention may include an upper conductor 100 and a lower conductor 300, both extending in the same direction and separated by a dielectric substrate or air. The upper conductor 100 includes a stripline 110 and a resonant patch 104 along its extension direction. The first end of the stripline is connected to a coaxial feed line. The resonant patch receives and radiates the electromagnetic energy remaining after passing through the stripline. The lower conductor 300 includes multiple second substructures 310 separated by cutouts along its extension direction. Adjacent second substructures can be directly separated by air or electrically connected by narrow wires. The second substructure at the first end of the lower conductor is connected to the coaxial feed line. The resonant patch at the second end of the upper conductor and the second substructure at the second end of the lower conductor are open circuits. The lower conductor serves as the antenna's ground plane, which can optimize antenna matching performance.

[0042] The spacing between the multiple second substructures of the lower conductor is d, where d = 1 / 4λ ~ λ, and λ is the wavelength corresponding to the operating frequency band of the antenna, so that the antenna has a good matching state in the operating frequency band.

[0043] In practical applications, the antenna can be installed perpendicular to the ground. The stripline 110 at the first end of the upper conductor 100 and the second substructure 310 at the first end of the lower conductor 300 can be used to connect to the center feed line and ground of the feed coaxial line, feeding energy into the upper conductor 100 and the lower conductor 300 through the feed coaxial line. Within the WLAN dual-band, the antenna can be considered a monopole antenna, and the end-loaded resonant patch 104 can be considered as the end capacitive load of the monopole antenna to improve port matching conditions. Figure 5 and Figure 6 The antenna radiation patterns of the antenna provided in the embodiments of the present invention are shown in the 2.4G and 5G frequency bands. The antenna can achieve omnidirectional broadband radiation within the WLAN operating frequency band.

[0044] Classical leaky wave antennas typically have a whip-like shape and, as traveling wave antennas, possess broadband characteristics. However, they also suffer from challenges in miniaturization, lower wide-side radiation effects than standard antennas, and the inability to achieve omnidirectional radiation. Furthermore, the beam pointing of leaky wave antennas designed based on strongly dispersive waveguides is difficult to maintain stably over a wide frequency range. This invention provides another preferred solution that, while maintaining omnidirectional broadband radiation characteristics, fully utilizes the broadband features of the leaky wave antenna and improves antenna efficiency through a resonant structure, achieving dual-band omnidirectional radiation in both the 2.4 GHz and 5 GHz bands. The preferred solution is described below.

[0045] refer to Figures 7 to 10 , Figure 7 An exploded view of the antenna provided in an embodiment of the present invention is shown. Figures 8 to 10 The following are schematic diagrams of the antenna structure provided in the embodiments of the present invention, viewed from the right, top, and bottom. Figure 11 This is a top-view structural diagram of a single modulation cycle of the antenna. (Combined with...) Figures 7 to 11 As shown, the antenna provided in this embodiment of the invention may include an upper conductor 100 and a lower conductor 300, both conductors extending in the same direction and separated by a dielectric substrate or air. The upper conductor 100, along its extension direction, sequentially includes a feed segment 101 at a first end, a modulation period in the middle, and a resonant patch 104 at a second end. The feed segment may include a microstrip line with trapezoidal dimensions, used to connect to the center feed line of the coaxial feed line. The modulation period may include multiple periodic first substructures 110, arranged sequentially along the extension direction. Each first substructure includes a comb line 102 and a strip line 103. The resonant patch receives and radiates the electromagnetic energy remaining after passing through multiple periodic first substructures. The lower conductor 300, along its extension direction, sequentially includes multiple second substructures 310 separated by cutouts. Adjacent second substructures may be directly separated by air or electrically connected by narrow wires. The second substructure at the first end of the lower conductor is used to connect to the ground of the coaxial feed line. The resonant patch at the second end of the upper conductor and the second substructure at the second end of the lower conductor are open circuits. The lower conductor serves as the antenna's ground plane, optimizing antenna matching. This structure retains both the broadband characteristics of a leaky antenna and the high efficiency of a resonant antenna, achieving omnidirectional and full-coverage dual-band WLAN with the advantages of broadband bandwidth and high radiation efficiency.

[0046] The coaxial feed line feeds both the upper and lower conductors. In the modulation period of the upper conductor, striplines and comblines alternate, allowing electromagnetic waves to propagate along the upper conductor. The quasi-TEM wave supported by the striplines and the surface slow wave supported by the comblines form a periodic mode modulation, generating wide-side omnidirectional leakage radiation. Simultaneously, the self-cancellation capability of the naturally reflected waves from the mode modulation promotes effective wide-side leakage radiation. Electromagnetic waves are emitted outward through the gaps in the comblines of multiple first substructures of the upper conductor and the resonant patch at the second end of the upper conductor. The periodic modulation leakage radiation and the end resonant radiation form a hybrid radiation mode. The antenna can simultaneously possess the broadband characteristics of a leakage antenna and the high efficiency of a resonant antenna, exhibiting omnidirectional broadband radiation characteristics. This makes the antenna promising for applications in multi-band wireless local area networks and other wireless communication systems, especially in special cases requiring omnidirectional broadband radiation effects.

[0047] The end-resonant structure (resonant patch) at the second end of the upper conductor can be circular, elliptical, or polygonal. The end-resonant structure can have various shapes, offering greater flexibility and facilitating practical selection. The multiple second substructures of the lower conductor are completely separated by the aforementioned perforations. The surface waves guided by the comb lines are called artificial surface plasmons, which do not require a complete ground plane like microstrip lines. This ensures omnidirectional radiation of electromagnetic waves in the azimuth plane, providing a wide coverage area. The multiple second substructures of the lower conductor are connected by narrow wires, constructing a complete ground plane for better matching of the antenna port.

[0048] The periodic structure length of the multiple periodic first substructures of the modulation period in the middle of the upper conductor is p, where p = 1 / 4λ ~ λ, and λ is the wavelength corresponding to the operating frequency band of the antenna. That is, p includes the length of a comb line 102 and a strip line 103. According to the theory of periodic modulation modes, the radiation angle of the antenna in the operating frequency band is in the wide side direction.

[0049] The spacing between the multiple second substructures of the lower conductor is d, where d = 1 / 4λ ~ λ, and λ is the wavelength corresponding to the operating frequency band of the antenna, so that the antenna has a good matching state in the operating frequency band.

[0050] And p > d, that is, the periodic structure length p of multiple periodic first substructures is greater than the spacing width d between multiple second substructures of the lower conductor.

[0051] The present invention also provides a communication device, which may include a radio frequency circuit and one or more antennas as described above, wherein the radio frequency circuit is used for communication using the antennas.

[0052] The antenna described in this invention has omnidirectional broadband radiation characteristics, making the communication equipment very suitable for 2.4G and 5G dual-band router applications.

[0053] In practical applications, the antenna can be installed perpendicular to the ground. The feed section 101 of the upper conductor 100 and the second substructure at the first end of the lower conductor 300 can be connected to the feed coaxial line. Energy is fed into the upper conductor 100 and the lower conductor 300 through the feed coaxial line. In the 2.4 GHz band, the total length of the antenna is comparable to the operating wavelength, and it can be regarded as a slender monopole operating in a pure resonant state. At this time, the end-loaded resonant patch 104 can be regarded as the end capacitive load of the monopole antenna to improve the port matching conditions. In the 5 GHz band, since the comb line 102 supports artificial surface plasmon slow waves and the stripline 103 supports quasi-TEM waves, there is a mode mismatch between the two. According to the mode modulation leakage theory, the periodic design of the mode mismatch will excite higher-order spatial harmonics. When the modulation period is designed to meet the condition that the spatial harmonics are fast waves, the guided wave can radiate outward in the form of a leakage wave. At the same time, the resonant patch 104 also radiates towards the wide side (i.e., towards the side of the leaky antenna), consistent with the leaky radiation, further enhancing the antenna's radiation performance in the wide side direction.

[0054] Figure 12 This diagram illustrates the three-dimensional antenna radiation pattern of the antenna provided in the embodiment of the present invention in the 2.4 GHz band. In actual use, the antenna is placed perpendicular to the ground. The feed section 101 of the upper conductor 100 is connected to the center feed line of the feed coaxial line, and the second substructure at the first end of the lower conductor 300 is connected to the ground (i.e., the outer conductor) of the feed coaxial line. Energy is fed into the upper conductor 100 and the lower conductor 300 through the feed coaxial line. When electromagnetic waves are input from the port, a standing wave is formed, with only two anti-phase field distribution states within one wave period, which can be switched quickly. At this time, the antenna is equivalent to a third-order resonant mode dipole, which can realize a typical dipole radiation pattern with a length of 1 to 1.5λ (λ is the operating wavelength), and has... Figure 12 The antenna pattern shown is suitable for omnidirectional wide-side radiation applications. However, when a strong main beam exists along the wide side, two distinct sidelobes inevitably form on either side of the main beam. This results in a reduction in energy along the main beam, thus reducing the antenna gain in the azimuth direction. However, in 2.4G Wi-Fi mode, this antenna gain is acceptable in applications. Compared to the 5G band, the electromagnetic wave wavelength of the 2.4G band is longer, naturally providing better signal coverage.

[0055] Figure 13This diagram illustrates the three-dimensional antenna radiation pattern of the antenna provided in the 5G band according to an embodiment of the present invention. In actual use, the antenna is placed perpendicular to the ground. The feed section 101 of the upper conductor 100 is connected to the center feed line of the feed coaxial line, and the second substructure at the first end of the lower conductor 300 is connected to the ground (i.e., the outer conductor) of the feed coaxial line. Energy is fed into the upper conductor 100 and the lower conductor 300 through the feed coaxial line. In the mode-tuning leakage region of the antenna, i.e., at the periodic first substructure 110 of the upper conductor 100, the antenna exhibits a typical TWM state, i.e., the equiphase surface moves forward with the wave. Unlike traditional leaky antennas, electromagnetic waves enter the resonant patch 104 through the leakage structure. This part behaves as a typical patch antenna, also radiating in the wide-side direction, which is consistent with leaky radiation. Based on the hybrid radiation scheme, the antenna significantly improves antenna efficiency while fully utilizing the broadband and high directivity of the leaky antenna. The resulting antenna radiation pattern is shown below. Figure 7 As shown, the antenna achieves highly directive omnidirectional coverage in the wide-side direction.

[0056] refer to Figure 14 , Figure 14 This diagram illustrates an application scenario where the antenna provided in this embodiment of the invention is used as a home router antenna. The metal base, serving as the metal floor 400 for the two antennas, is designed to be the size of a standard 200mm × 140mm router. Two identical antennas are symmetrically mounted at two corners of the metal floor 400 and fixed to it via separate coaxial feed SMAs, referred to as the first feed coaxial line 1 and the second feed coaxial line 2, respectively. The center feed line of the feed coaxial line is connected to the feed segment 101 of the upper conductor 100 of the antenna, and the outer conductor (ground) of the feed coaxial line is connected to the lower conductor 300, which serves as the ground plane. Hereinafter, the first feed coaxial line 1 is defined as port 1, and the second feed coaxial line 2 as port 2. Furthermore, in the description of this invention, the definition of the xoy axis has been... Figure 14 The annotations are for easy description in subsequent analysis.

[0057] Figure 15 for Figure 14The diagram shows the S-parameter curves of a home router antenna. S-parameters are network parameters based on the relationship between incident and reflected waves, suitable for microwave circuit analysis. They describe the circuit network using the reflected signal at a device port and the signal transmitted from that port to another. For a two-port network, the four S-parameters are: Sij represents the energy injected from port j and measured at port i. For example, S11 is defined as the square root of the ratio of the energy reflected from port 1 to the input energy, often simplified to the ratio of the equivalent reflected voltage to the equivalent incident voltage. The physical meanings of each parameter and the characteristics of special networks are as follows: S11—Reflection coefficient of port 1 (input return loss) when port 2 is matched; S22—Reflection coefficient of port 2 (output return loss) when port 1 is matched; S12—Transmission coefficient from port 2 to port 1 when port 1 is matched; S21—Transmission coefficient from port 1 to port 2 when port 2 is matched. Where S11 and S22 are port reflection coefficients; S12 and S21 are port transmission coefficients. Port matching means that there is no reflection at that port.

[0058] like Figure 15 As shown, the simulated reflection coefficients (|S11| and |S22|) and transmission coefficients (|S21| and |S12|) of the two antennas are precisely coincident. Based on the simulated port matching status, the simulated |S11| achieves a value less than -10dB in both the 2.4G and 5G bands specified by IEEE 802.11ax (WiFi 6). Simultaneously, due to the large spacing between the two antennas, their mutual interference is relatively small, remaining below -25dB in both the 2.4G and 5G bands. In actual measurements, due to differences in the fabrication consistency and installation process of the two antennas, their S-parameters are not perfectly matched as in the simulation results, but their trend is consistent with the simulation results, simultaneously meeting the requirements of both the 2.4G and 5G operating bands. Only in the 5G band is the interference between the two slightly reduced, with |S21| (|S12|) reaching a maximum of -21dB. These results demonstrate that this scheme successfully achieves a dual-band design for 2.4G and 5G in terms of port performance indicators.

[0059] Figure 16 for Figure 14 The image shows simulated and measured three-dimensional radiation patterns of a home router antenna at 2.4 GHz and 5.5 GHz. Figure 16 As shown in (a) to (d), when the two feed ports are powered separately, they exhibit similar radiation characteristics, both achieving omnidirectional radiation over a wide side. Particularly in the 5G band, due to its shorter operating wavelength, the radiation characteristics are least affected by the metal floor 400, exhibiting higher directivity, which is beneficial for enhancing 5G band WiFi signal coverage.

[0060] Figure 17 for Figure 14The image shows a simulated and measured two-dimensional xoy plane radiation pattern of a home router antenna in the 2.4 GHz band. Figure 17 As shown in (a) and (b), due to the longer operating wavelength in the 2.4G band, the antenna is more susceptible to the influence of the metal ground plane 400. Two orthogonal polarization components (φ-polarization and θ-polarization) coexist. However, for practical dual-band routers, the requirements for radiation pattern distribution in the 2.4G band are generally not as strict as those in the 5G band. In practical applications, such radiation effect is good.

[0061] Figure 18 for Figure 14 The image shows a two-dimensional radiation pattern of a home router antenna in the 5G band, both simulated and measured. Figure 18 As shown in (a) to (f), due to the hybrid operating scheme of leakage and resonant radiation, the home router antenna exhibits omnidirectional radiation capability in the 5G band while maintaining good beam pointing stability. At the three frequency points of 5.15GHz, 5.5GHz, and 5.85GHz, the measured radiation angles are -2.5°, 1°, and 3.5°, respectively, essentially remaining along the wide side, making it very suitable for router applications. This result demonstrates that the hybrid leakage and resonant scheme further reduces the dispersion effect of leakage radiation, which is one of the advantages of the antenna provided in this embodiment compared to traditional leakage antennas.

[0062] Figure 19 for Figure 14 The diagram shows the antenna efficiency of a home router antenna, based on simulation and measurement. Antenna efficiency refers to the ratio of radiated power to input power, and is an important indicator of antenna performance. The difference between total efficiency and radiation efficiency lies in whether port matching is considered. Most end-matched leaky antennas have high radiation efficiency, but some energy is absorbed by the end load. Therefore, unless the antenna is made longer to maximize energy radiation, their total efficiency is usually low, which is detrimental to the miniaturization design of leaky antennas. The antenna provided in this embodiment replaces the end-matching load with a resonant patch, avoiding the above problem and thus achieving higher antenna efficiency. Figure 19 As shown, in the simulation, the antenna's radiation efficiency and overall efficiency remained above 90% in both the 2.4 GHz and 5 GHz bands. And... Figure 14 In the actual home router antenna measurements shown, the total radiation efficiency of the two antennas was 83.1% and 81.5% in the 2.4 GHz band, and 86.5% and 86.1% in the 5 GHz band, respectively, which is better than other antennas used in WLAN systems.

[0063] In summary, the antenna of this invention features broadband and omnidirectional radiation, retaining the broadband characteristics of a leaky antenna while maintaining the advantages of high efficiency and high radiation efficiency of a resonant antenna, thus achieving broadband omnidirectional and full coverage for dual-band WLAN.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An antenna, characterized by, It includes an upper conductor and a lower conductor that do not directly contact each other and extend in the same direction. The upper conductor includes a radiation section and a resonant patch in sequence along the extension direction. The radiation section includes a feed section and a modulation period. The modulation period includes multiple periodic first substructures arranged in sequence along the extension direction. Each first substructure includes a comb line and a strip line. The lower conductor includes multiple spaced second substructures along its extension direction. These second substructures are directly separated by air or electrically connected by narrow wires. The radiating section at the first end of the upper conductor and the second substructure at the first end of the lower conductor are connected to the center feed line of the feeding coaxial line and ground, respectively. The feeding coaxial line feeds the upper and lower conductors, and electromagnetic waves are emitted outward through the upper and lower conductors. In the 2.4G band, the antenna is in pure resonant mode. In the 5G band, the comb line supports artificial surface plasmon slow waves, the strip line supports quasi-TEM waves, and the guided wave radiates outward in the form of a leaky wave. At the same time, the resonant patch radiates to the wide side, achieving omnidirectional broadband radiation characteristics.

2. The antenna according to claim 1, characterized in that, The periodic structure length of the multiple periodic first substructures is p, p = 1 / 4λ ~ λ, and the spacing width between adjacent second substructures of the lower conductor is d, d = 1 / 4λ ~ λ, and p > d, where λ is the wavelength corresponding to the operating frequency band of the antenna.

3. The antenna according to claim 1, characterized in that, The upper conductor and the lower conductor are separated by a dielectric substrate or an air layer.

4. The antenna according to claim 1, characterized in that, The length of the radiating segment is , =3 / 4λ~3λ, where λ is the wavelength corresponding to the operating frequency band of the antenna.

5. The antenna according to claim 1, characterized in that, The spacing width between adjacent second substructures of the lower conductor is d, where d = 1 / 4λ ~ λ, and λ is the wavelength corresponding to the operating frequency band of the antenna.

6. The antenna according to claim 1, characterized in that, The feed section at the first end of the upper conductor includes a microstrip line with a trapezoidal size, used to connect to the feed coaxial line.

7. A communication device, characterized in that, It includes a radio frequency circuit and an antenna as described in any one of claims 1 to 6, wherein the radio frequency circuit is used for communication using the antenna.

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