Compact omnidirectional broadband high-efficiency full-duplex binary antenna pair based on dipole antenna

Abstract

The invention discloses a compact omnidirectional broadband high-efficiency full-duplex binary antenna pair based on a dipole antenna, which relates to the technical field of dipole antennas, and comprises a near-field resonance parasitic structure, a first dielectric substrate, two Egypt battle axe dipoles, a second dielectric substrate and two feed dipoles, the near-field resonance parasitic structure is arranged on the upper surface of the first dielectric substrate, the two Egypt battle axe dipoles are arranged on the lower surface of the first dielectric substrate, and the two feed dipoles are arranged on the lower surface of the second dielectric substrate; the lower surface of the first dielectric substrate is fixedly connected with the upper surface of the second dielectric substrate; the antenna has the advantages of miniaturization, low profile, high isolation, high efficiency, stable omnidirectional performance and wide working bandwidth, and can be applied to a high-performance indoor terminal communication WiFi antenna system with a compact size.

Description

Technical Field

[0001] The present invention relates to the technical field of dipole antennas, and particularly to a compact omnidirectional broadband high-efficiency full-duplex dual-antenna pair based on dipole antennas. Background Art

[0002] With the rapid development of wireless local area networks and the explosive growth of intelligent terminals, the demand for indoor base stations and WLAN antenna technology shows a trend of co-evolution. In view of the high requirements for signal full coverage after routers and wireless terminals access indoor terminal devices, omnidirectional antennas have received wide attention in indoor wireless communication. On the one hand, with the continuous development of wireless communication, the congestion of spectrum resources has become a bottleneck restricting its further development. On the other hand, the explosive growth of users and devices requires improving the efficiency of communication systems to maintain good data rates or even reach higher rates, and in-band full-duplex systems have the potential to improve the spectrum efficiency and communication rate of next-generation wireless communication networks. In addition, under the trend of miniaturization and integration of mobile communication devices, the structural design of mobile terminals continues to evolve towards compactness and miniaturization, and this morphological change has led to severe spatial constraint challenges for antenna layout. Therefore, in modern wireless communication systems, researching compact omnidirectional broadband high-efficiency in-band full-duplex antennas that meet the above application requirements has great industrial attractiveness.

[0003] However, a compact omnidirectional broadband high-efficiency in-band full-duplex antenna needs to maintain a high isolation degree between antenna pairs. In related technologies, most methods such as physical separation, using polarization diversity, loading resonators between antenna elements, and near-field cancellation technology are used to solve the high isolation degree problem. Physical separation reduces coupling by directly increasing the distance between the transmitting and receiving antennas, but it will cause the antenna size to be too large; polarization diversity reduces coupling by making the transmitting and receiving antennas in an orthogonal polarization state, but it is not conducive to maintaining the consistency of transmission and reception; loading structures such as resonators (such as tunable resonators and electromagnetic bandgap structures) between antennas to reduce coupling will increase the complexity and loss of the antenna and reduce the overall system efficiency. In addition, the near-field cancellation technology reduces the coupling between ports by placing the receiving antenna at the near-field zero point of the transmitting antenna. Although this method can effectively reduce coupling, the antenna design complexity is relatively high.

[0004] In view of the above problems, antenna shaping, path cancellation, and common-mode - differential-mode cancellation and other methods are also used in related technologies for in-band full-duplex dual-antenna pairs with a compact spacing. However, although the above methods can achieve good decoupling, they still have problems such as narrow impedance bandwidth and decoupling bandwidth, and deterioration of the omnidirectional performance of the antenna, and it is difficult to be applicable to the applications of indoor terminals.

[0005] Therefore, there is an urgent need for a simple, miniaturized, high-efficiency, and low-cost omnidirectional in-band full-duplex WiFi antenna technology. Summary of the Invention

[0006] In view of this, the present invention provides a compact omnidirectional broadband high-efficiency full-duplex dipole antenna pair to solve the technical problems existing in the related art.

[0007] The present invention provides a compact omnidirectional broadband high-efficiency full-duplex dipole antenna pair, including: a near-field resonant parasitic structure, a first dielectric substrate, two Egyptian axe dipoles, a second dielectric substrate, and two feeding dipoles;

[0008] The near-field resonant parasitic structure is disposed on the upper surface of the first dielectric substrate, the two Egyptian axe dipoles are both disposed on the lower surface of the first dielectric substrate, and the two feeding dipoles are both disposed on the lower surface of the second dielectric substrate; the lower surface of the first dielectric substrate is fixedly connected to the upper surface of the second dielectric substrate.

[0009] In an optional embodiment, copper layers are covered on the upper surface of the first dielectric substrate and the lower surface of the second dielectric substrate; a copper layer is covered on the lower surface of the first dielectric substrate or the upper surface of the second dielectric substrate; the near-field resonant parasitic structure is printed on the copper layer on the upper surface of the first dielectric substrate; the two feeding dipoles are printed on the copper layer on the lower surface of the second dielectric substrate; the two Egyptian axe dipoles are printed on the copper layer on the lower surface of the first dielectric substrate or the upper surface of the second dielectric substrate.

[0010] In an optional embodiment, the near-field resonant parasitic structure includes two comb-shaped strips distributed symmetrically and a connecting strip with a left-right symmetric shape; both ends of the connecting strip are respectively connected to a comb-shaped strip.

[0011] In an optional embodiment, the comb-shaped strip is composed of multiple short strips and a long strip passing through the midpoints of the multiple short strips; the number of short strips is 2n - 1, and they are arranged at intervals from top to bottom in sequence. The midpoint of each short strip is located on the same vertical line, and the vertical line coincides with the long strip; the comb-shaped strip is a vertically symmetric structure, and the horizontal symmetry axis coincides with the nth short strip; the lengths and widths of the first to nth short strips are all different.

[0012] In an alternative embodiment, the connecting strip includes two edge connecting strips symmetrically distributed up and down, two series-connected first intermediate connecting strips and second intermediate connecting strips located between the two edge connecting strips; the edge connecting strip includes a first bent portion, a second bent portion, an intermediate connecting portion, a third bent portion and a fourth bent portion; the edge connecting strip is a left-right symmetric structure, and the vertical symmetry axis coincides with the midpoint of the intermediate connecting portion; one end of the first bent portion is connected to the long strip on the left, and the other end is perpendicularly connected to one end of the second bent portion; both ends of the intermediate connecting portion are respectively perpendicularly connected to the other end of the second bent portion and one end of the third bent portion; the other end of the third bent portion is connected to one end of the fourth bent portion, and the other end of the fourth bent portion is connected to the long strip on the right; one end of the first intermediate connecting strip is connected to the nth short strip on the left, one end of the second intermediate connecting strip is connected to the nth short strip on the right, and the other end of the first intermediate connecting strip is connected to the other end of the second intermediate connecting strip; the lengths and widths of the first bent portion, the second bent portion, the intermediate connecting portion and the first intermediate connecting strip are all different; the lengths and widths of the first intermediate connecting strip and the second intermediate connecting strip are the same.

[0013] In an alternative embodiment, it further includes: a first capacitor, a second capacitor and a third capacitor; the first capacitor is connected in series in the internal network of the intermediate connecting portion located above, the second capacitor is connected in series in the internal network of the intermediate connecting portion located below, and both ends of the third capacitor are respectively connected to the other end of the first intermediate connecting strip and the other end of the second intermediate connecting strip.

[0014] In an alternative embodiment, both the first dielectric substrate and the second dielectric substrate are made of F4BM220 material, with a relative dielectric constant of 2.2 and a loss tangent of 0.001.

[0015] In an alternative embodiment, there is a first gap between the two Egyptian battle-axe dipoles, and they are symmetrically distributed left and right; each Egyptian battle-axe dipole includes a vertical arm and two top hat structures; the two top hat structures are respectively arranged at both ends of the vertical arm; a first slit is provided at the midpoint of the vertical arm;

[0016] There is a second gap between the two feeding dipoles, and they are symmetrically distributed left and right; a second slit is provided at the midpoint of each feeding dipole;

[0017] Both the first slit and the second slit coincide with the horizontal center line of the first dielectric substrate.

[0018] In an alternative embodiment, the rotation angle of the top hat structure of the Egyptian tomahawk dipole is 40°, the outer diameter and inner diameter are 35 mm and 35 mm respectively, the lengths of the first gap and the second gap are both 51 mm, the length of the first slot is 0.5 mm; the length of the second slot is 0.75 mm.

[0019] In an alternative embodiment, the lengths, widths and heights of the first dielectric substrate and the second dielectric substrate are 80 mm, 70.4 mm and 0.254 mm respectively, and the thicknesses of the copper layer on the upper surface of the first dielectric substrate, the copper layer on the lower surface of the second dielectric substrate, and the copper layer on the lower surface of the first dielectric substrate or the upper surface of the second dielectric substrate are all 0.017 mm.

[0020] The embodiments of the present invention have the following beneficial effects:

[0021] 1) Wideband performance: By adding a near-field resonant parasitic structure to the upper layer of the Egyptian tomahawk dipole and superimposing multiple adjacent resonant modes, the bandwidth of the antenna is extended. The -10 dB impedance bandwidth of the antenna is 1.24 - 1.55 GHz;

[0022] 2) High isolation performance: By loading connection strips with multiple series capacitors, a new coupling path is introduced, and high isolation performance is achieved without any complex decoupling network. The isolation bandwidth between the two ports is 1.27 - 1.52 GHz, and the maximum isolation can reach 50 dB; the antenna pair avoids the introduction of a complex decoupling network, thereby effectively reducing the design complexity and energy loss.

[0023] 3) Omnidirectional radiation pattern performance: The antenna pair maintains a good omnidirectional radiation pattern within the operating bandwidth.

[0024] 4) Miniaturized design: The antenna pair has a compact structure, and the overall size is 0.33×0.29×0.002λ L 3 , which is suitable for indoor terminal communication scenarios with limited size.

[0025] 5) Simple and multifunctional: By loading connection strips with series capacitors between two comb-shaped strips, the comb-shaped strip on the upper layer and the connection strip as a whole can be regarded as a near-field resonant parasitic structure. This structure can not only broaden the bandwidth of the antenna pair, effectively decouple, but also improve the omnidirectional performance of the antenna, and the structure of this antenna is simple and does not require any decoupling network. Description of the Drawings

[0026] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the accompanying drawings required for the description of the specific embodiments or the prior art. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0027] Figure 1 is an exploded view of the structure of a compact omnidirectional broadband high-efficiency full-duplex dual antenna pair based on a dipole antenna according to an embodiment of the present invention;

[0028] Figure 2 is a schematic structural diagram of a near-field resonant parasitic structure according to an embodiment of the present invention;

[0029] Figure 3 is an axonometric view of a compact omnidirectional broadband high-efficiency full-duplex dual antenna pair based on a dipole antenna according to an embodiment of the present invention;

[0030] Figure 4 is a schematic structural diagram of an Egyptian tomahawk dipole according to an embodiment of the present invention;

[0031] Figure 5 is a schematic structural diagram of a feeding dipole according to an embodiment of the present invention;

[0032] Figure 6 is a graph of reflection coefficient and isolation coefficient according to an embodiment of the present invention;

[0033] Figure 7 is a graph of efficiency according to an embodiment of the present invention;

[0034] Figure 8 is the radiation pattern of the antenna pair at 1.275 GHz in the plane when the single port is excited according to an embodiment of the present invention;

[0035] Figure 9 is the radiation pattern of the antenna pair at 1.4 GHz in the plane when the single port is excited according to an embodiment of the present invention;

[0036] Figure 10 is the radiation pattern of the antenna pair at 1.52 GHz in the plane when the single port is excited according to an embodiment of the present invention.

[0037] Reference numerals:

[0038] 1. Near-field resonant parasitic structure; 11. Comb-shaped strip; 111. Short strip; 112. Long strip; 12. Connecting strip; 121. Edge connecting strip; 1211. First bending part; 1212. Second bending part; 1213. Intermediate connecting part; 1214. Third bending part; 1215. Fourth bending part; 122. First intermediate connecting strip; 123. Second intermediate connecting strip; 2. First dielectric substrate; 3. Egyptian tomahawk dipole; 31. Vertical arm; 311. First slit; 32. Top hat structure; 4. Second dielectric substrate; 5. Feeding dipole; 51. Second slit. Detailed implementation manners

[0039] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0040] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0041] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can also be the internal communication of two elements. It can be a wireless connection or a wired connection. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0042] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0043] Figure 1A compact omnidirectional broadband high-efficiency full-duplex dual-antenna pair based on a dipole antenna according to an embodiment of the present invention can be used in a high-performance indoor terminal communication WiFi antenna system with a compact size. The antenna adopts a compact design and realizes miniaturization, high isolation, wide bandwidth, and omnidirectional radiation performance by adding a near-field resonant parasitic structure, meeting the requirements of omnidirectionality, wide bandwidth, and miniaturization for WiFi antennas in indoor terminal communication. Specifically, it includes: a near-field resonant parasitic structure 1, a first dielectric substrate 2, two Egyptian tomahawk dipoles 3, a second dielectric substrate 4, and two feeding dipoles 5.

[0044] Specifically, the near-field resonant parasitic structure 1 is disposed on the upper surface of the first dielectric substrate 2, the two Egyptian tomahawk dipoles 3 are both disposed on the lower surface of the first dielectric substrate 2, and the two feeding dipoles 5 are both disposed on the lower surface of the second dielectric substrate 4; the lower surface of the first dielectric substrate 2 and the upper surface of the second dielectric substrate 4 are fixedly connected.

[0045] It should be noted that, as Figure 2 shown, the first dielectric substrate 2 and the second dielectric substrate 4 have the same size, with a length, width, and height of l sub , w sub and h1, respectively.

[0046] In an optional implementation manner, copper layers are covered on the upper surface of the first dielectric substrate 2 and the lower surface of the second dielectric substrate 4; a copper layer is covered on the lower surface of the first dielectric substrate 2 or the upper surface of the second dielectric substrate 4; the copper layer on the upper surface of the first dielectric substrate 2 is printed with the near-field resonant parasitic structure 1 for realizing the broadening of the antenna bandwidth, the realization of high isolation, and the improvement of omnidirectional performance; the copper layer on the lower surface of the second dielectric substrate 4 is printed with two feeding dipoles 5; the copper layer on the lower surface of the first dielectric substrate 1 or the upper surface of the second dielectric substrate 4 is printed with two Egyptian tomahawk dipoles 3.

[0047] Among them, as Figure 2 shown, the thickness of all the above copper layers is h2.

[0048] It should be noted that a copper layer is shared between the first dielectric substrate 2 and the second dielectric substrate 4. For example, when a copper layer is covered on the lower surface of the first dielectric substrate 2, a layer of PP glue can be applied to the upper surface of the second dielectric substrate 4. At this time, the upper surface of the second dielectric substrate 4 can be adhesively fixed to the copper layer on the lower surface of the first dielectric substrate 2 through the PP glue to form an integral body; similarly, when a copper layer is covered on the upper surface of the second dielectric substrate 4, a layer of PP glue can be applied to the lower surface of the first dielectric substrate 4. At this time, the lower surface of the first dielectric substrate 2 can be adhesively fixed to the copper layer on the upper surface of the second dielectric substrate 4 through the PP glue to form an integral body.

[0049] In an alternative embodiment, the length, width, and height of the first dielectric substrate 2 and the second dielectric substrate 4 are 80 mm, 70.4 mm, and 0.254 mm respectively, and the thickness of the copper layer on the upper surface of the first dielectric substrate 2, the copper layer on the lower surface of the second dielectric substrate 4, and the copper layer on the lower surface of the first dielectric substrate 2 or the upper surface of the second dielectric substrate 4 is 0.017 mm.

[0050] The overall structure of the embodiment of the present invention is composed of a first dielectric substrate 2, a second dielectric substrate 4, and three copper layers, and the overall size is 80 mm × 70.4 mm × 0.559 mm, that is, 0.33 × 0.29 × 0.002λ L 3, where λ L is the wavelength of the antenna in free space calculated based on the lowest frequency f L within the antenna bandwidth as the standard, and c is the speed of light.

[0051] In an alternative embodiment, as Figure 3 shown, the near-field resonant parasitic structure 1 includes two comb-shaped strips 11 distributed symmetrically and a connecting strip 12 with a left-right symmetric shape; both ends of the connecting strip 12 are respectively connected to one comb-shaped strip 11.

[0052] In an alternative embodiment, the comb-shaped strip 11 is composed of multiple short strips 111 and a long strip 112 passing through the midpoints of the multiple short strips; the number of short strips 111 is 2n - 1, and they are arranged at intervals from top to bottom in sequence. The midpoint of each short strip 111 is located on the same vertical line, and the vertical line coincides with the long strip 112; the comb-shaped strip 11 is a vertically symmetric structure, and the horizontal symmetry axis coincides with the nth short strip; the lengths and widths of the 1st to nth short strips are all different.

[0053] Preferably, n is taken as 4 and the interval distances are equal. The lengths of the short strips 111 from top to bottom are l1, l2, l3, and l4 in sequence, and the widths are w1, w2, w3, and w4 in sequence. Since the comb-shaped strip 11 is a vertically symmetric structure, the lengths and widths of each short strip in the lower symmetric part are the same as those in the upper symmetric part, which will not be elaborated here. The length and width of the long strip 112 are l9 and w9 respectively. Since the two comb-shaped strips 11 are distributed symmetrically left and right, the lengths and widths of the short strips 111 and the long strip 112 of the comb-shaped strip 11 on the left are the same as those of the corresponding short strips 111 and the long strip 112 at the corresponding positions of the comb-shaped strip 11 on the right, which will not be elaborated here.

[0054] In an alternative embodiment, the connecting strip 12 includes two edge connecting strips 121 symmetrically distributed up and down, two series-connected first intermediate connecting strips 122 and a second intermediate connecting strip 123 located between the two edge connecting strips; the edge connecting strip 121 includes a first bending portion 1211, a second bending portion 1212, an intermediate connecting portion 1213, a third bending portion 1214 and a fourth bending portion 1215; the edge connecting strip 121 is a left-right symmetric structure, and the vertical symmetry axis coincides with the midpoint of the intermediate connecting portion 1213; one end of the first bending portion 1211 is connected to the long strip 112 on the left, and the other end is perpendicularly connected to one end of the second bending portion 1212; both ends of the intermediate connecting portion 1213 are respectively perpendicularly connected to the other end of the second bending portion 1212 and one end of the third bending portion 1214; the other end of the third bending portion 1214 is connected to one end of the fourth bending portion 1215, and the other end of the fourth bending portion 1215 is connected to the long strip 112 on the right; one end of the first intermediate connecting strip 122 is connected to the nth short strip on the left, one end of the second intermediate connecting strip 123 is connected to the nth short strip on the right, and the other end of the first intermediate connecting strip 122 is connected to the other end of the second intermediate connecting strip 123; the lengths and widths of the first bending portion 1211, the second bending portion 1212, the intermediate connecting portion 1213 and the first intermediate connecting strip 122 are all different; the lengths and widths of the first intermediate connecting strip 122 and the second intermediate connecting strip 123 are the same.

[0055] Specifically, the length and width of the first bending portion 1211 are l6 and w6 respectively, the length and width of the second bending portion 1212 are l7 and w7 respectively, and the length and width of the intermediate connecting portion 1213 are l8 and w8 respectively. The lengths and widths of the first intermediate connecting strip 122 and the second intermediate connecting strip 123 are both l5 and w5. Since the two edge connecting strips 121 are symmetrically distributed up and down and the edge connecting strip 121 is a left-right symmetric structure, the dimensions of other parts are not described herein again.

[0056] In an alternative embodiment, the compact omnidirectional broadband high-efficiency full-duplex dipole antenna pair further includes: a first capacitor C1, a second capacitor C2 and a third capacitor C3; the first capacitor C1 is connected in series in the internal network of the intermediate connecting portion 1213 located above, the second capacitor C2 is connected in series in the internal network of the intermediate connecting portion 1213 located below, and both ends of the third capacitor C3 are respectively connected to the other end of the first intermediate connecting strip 122 and the other end of the second intermediate connecting strip 123.

[0057] In the embodiment of the present invention, by loading a near-field resonant parasitic structure 1 on the upper surface of the first dielectric substrate 2, broadband, high isolation, and omnidirectional performance of the antenna pair can be achieved. Specifically, by loading two comb-shaped strips above the Egyptian tomahawk dipole, new resonant modes are introduced to broaden the bandwidth; a connecting strip with a series capacitor is added between the two comb-shaped strips to introduce a new coupling path, thereby achieving high isolation performance of the antenna pair. The connecting strip with the loaded series capacitor resonates in the horizontal direction, which can effectively correct the radiation pattern of the antenna and achieve good omnidirectional performance.

[0058] In an alternative embodiment, both the first dielectric substrate 2 and the second dielectric substrate 4 are made of F4BM220 material, with a relative dielectric constant of 2.2 and a loss tangent of 0.001.

[0059] In an alternative embodiment, as Figure 4 shown, there is a first gap between the two Egyptian tomahawk dipoles 3, and they are symmetrically distributed left and right; each Egyptian tomahawk dipole includes a vertical arm 31 and two top hat structures 32; the two top hat structures 32 are respectively arranged at both ends of the vertical arm 31; a first slit 311 is provided at the midpoint of the vertical arm 31 to facilitate the effective excitation of the Egyptian tomahawk dipole 3.

[0060] As Figure 5 shown, there is a second gap between the two feeding dipoles 5, and they are symmetrically distributed left and right; a second slit 51 is provided at the midpoint of each feeding dipole;

[0061] Both the first slit 311 and the second slit 51 coincide with the horizontal center line of the first dielectric substrate 2.

[0062] Specifically, the distance of the first gap of the Egyptian tomahawk dipole 3 is R d , the rotation angle of the top hat structure is a, the outer diameter and inner diameter are R1 and R2 respectively. The width of the vertical arm of the Egyptian tomahawk dipole is w 10 , the length of the first slit 311 is L1. The feeding dipole 5 is used to feed the entire antenna pair, and its structure is symmetric up and down. The length and width of the feeding dipole 5 are 2L2 - L3 and w 11 , the length of the second slit 51 is L3, and the distance of the second gap is also R d , and the distances of the first gap and the second gap are equal.

[0063] In an alternative embodiment, the rotation angle of the top hat structure of the Egyptian tomahawk dipole is 40°, the outer diameter and inner diameter are 35 mm and 34 mm respectively, the lengths of the first gap and the second gap are both 51 mm, the length of the first slit is 0.5 mm; the length of the second slit is 0.75 mm.

[0064] In summary, the embodiments of the present invention have the following beneficial effects:

[0065] 1) Wideband performance: By adding a near-field resonant parasitic structure to the upper layer of the Egyptian tomahawk dipole and superimposing multiple adjacent resonant modes, the bandwidth of the antenna is expanded. The -10 dB impedance bandwidth of the antenna is 1.24 - 1.55 GHz;

[0066] 2) High isolation performance: By loading connection strips with multiple series capacitors, a new coupling path is introduced, and high isolation performance is achieved without any complex decoupling network. The isolation bandwidth between the two ports is 1.27 - 1.52 GHz, and the maximum isolation can reach 50 dB; The antenna pair avoids the introduction of a complex decoupling network, thereby effectively reducing the design complexity and energy loss.

[0067] 3) Omnidirectional radiation pattern performance: The antenna pair maintains a good omnidirectional radiation pattern within the operating bandwidth.

[0068] 4) Miniaturized design: The antenna pair has a compact structure, and the overall size is 0.33×0.29×0.002λ L 3 , which is suitable for indoor terminal communication scenarios with limited size.

[0069] 5) Simple and multifunctional: By loading connection strips with series capacitors between two comb-shaped strips, the comb-shaped strip on the upper layer and the connection strip as a whole can be regarded as a near-field resonant parasitic structure. This structure can not only broaden the bandwidth of the antenna pair, effectively decouple, but also improve the omnidirectional performance of the antenna. Moreover, the structure of this antenna is simple and does not require any decoupling network.

[0070] Specifically, the optimal dimensions of each parameter in the embodiments of the present invention are shown in Table 1:

[0071] Table 1

[0072]

[0073]

[0074]

[0075] Through the above geometric parameter optimization, the antenna pair satisfies |S11| ≤ -10 dB within the frequency range of 1.24 - 1.55 GHz, and the maximum isolation of 50 dB can be achieved between the transceiver ports.

[0076] To verify the technical effects of the embodiments of the present invention, according to the designed structure and set parameters above, the HFSS software is used to simulate the performance of the compact omnidirectional broadband high-efficiency full-duplex dual antenna pair based on the dipole antenna, and the simulation results are as follows:

[0077] Reflection coefficient and isolation performance: As Figure 6 shown, the antenna pair satisfies the matching performance of |S11| ≤ -10 dB within the frequency range of 1.24 - 1.55 GHz, and at the same time achieves a high isolation bandwidth of |S21| < -20 dB within the frequency range of 1.27 - 1.52 GHz, with the maximum isolation degree reaching 50 dB.

[0078] Efficiency performance: As Figure 7 shown, the efficiency of the antenna pair is greater than 80% within the overlapping bandwidth of the impedance bandwidth and the isolation bandwidth.

[0079] Pattern performance: As Figures 8 - 10 shown, when the antenna pair is excited by a single port, it exhibits good omnidirectional characteristics, and the non-circularity of the antenna is less than 3 dB.

[0080] The present invention realizes high isolation, high efficiency, miniaturization, wide bandwidth and omnidirectional performance through an optimized near-field resonant parasitic structure and radiator structure, and is especially suitable for WiFi antennas for omnidirectional coverage of indoor terminal communication.

[0081] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A compact omnidirectional broadband high-efficiency full-duplex dual antenna pair based on dipole antennas, characterized in that Including: A near-field resonant parasitic structure, a first dielectric substrate, two Egyptian tomahawk dipoles, a second dielectric substrate, and two feeding dipoles; The near-field resonant parasitic structure is disposed on the upper surface of the first dielectric substrate, the two Egyptian tomahawk dipoles are both disposed on the lower surface of the first dielectric substrate, and the two feeding dipoles are both disposed on the lower surface of the second dielectric substrate; the lower surface of the first dielectric substrate and the upper surface of the second dielectric substrate are fixedly connected.

2. The compact omnidirectional broadband high-efficiency full-duplex dual antenna pair based on a dipole antenna according to claim 1, wherein The upper surface of the first dielectric substrate and the lower surface of the second dielectric substrate are both covered with a copper layer; the lower surface of the first dielectric substrate or the upper surface of the second dielectric substrate is covered with a copper layer; the near-field resonant parasitic structure is printed on the copper layer on the upper surface of the first dielectric substrate; Two feeding dipoles are printed on the copper layer on the lower surface of the second dielectric substrate; Two Egyptian tomahawk dipoles are printed on the copper layer on the lower surface of the first dielectric substrate or the upper surface of the second dielectric substrate.

3. The compact omnidirectional broadband high-efficiency full-duplex dipole antenna pair according to claim 1, characterized in that The near-field resonant parasitic structure includes two comb-shaped strips distributed symmetrically and a connecting strip with a left-right symmetric shape; both ends of the connecting strip are respectively connected to one comb-shaped strip.

4. The compact omnidirectional broadband high-efficiency full-duplex dipole antenna pair according to claim 3, characterized in that The comb-shaped strip is composed of multiple short strips and a long strip passing through the midpoints of the multiple short strips; the number of short strips is 2n - 1, and they are arranged at intervals from top to bottom in sequence, the midpoint of each short strip is located on the same vertical line, and the vertical line coincides with the long strip; the comb-shaped strip is a vertically symmetric structure, and the horizontal symmetry axis coincides with the nth short strip; the lengths and widths of the first to nth short strips are all different.

5. The compact omnidirectional broadband high-efficiency full-duplex dipole antenna pair according to claim 4, characterized in that The connecting strip includes two edge connecting strips distributed symmetrically up and down, two series-connected first intermediate connecting strips and second intermediate connecting strips located between the two edge connecting strips; the edge connecting strip includes a first bending part, a second bending part, an intermediate connecting part, a third bending part, and a fourth bending part; the edge connecting strip is a left-right symmetric structure, and the vertical symmetry axis coincides with the midpoint of the intermediate connecting part; one end of the first bending part is connected to the long strip on the left, and the other end is perpendicularly connected to one end of the second bending part; both ends of the intermediate connecting part are respectively perpendicularly connected to the other end of the second bending part and one end of the third bending part; the other end of the third bending part is connected to one end of the fourth bending part, and the other end of the fourth bending part is connected to the long strip on the right; one end of the first intermediate connecting strip is connected to the nth short strip on the left, one end of the second intermediate connecting strip is connected to the nth short strip on the right, and the other end of the first intermediate connecting strip is connected to the other end of the second intermediate connecting strip; the lengths and widths of the first bending part, the second bending part, the intermediate connecting part, and the first intermediate connecting strip are all different; the lengths and widths of the first intermediate connecting strip and the second intermediate connecting strip are the same.

6. The compact omnidirectional broadband high-efficiency full-duplex dipole antenna pair based on the dipole antenna according to claim 5, characterized in that It further includes: a first capacitor, a second capacitor and a third capacitor; the first capacitor is connected in series in the internal circuit of the middle connection part located above, the second capacitor is connected in series in the internal circuit of the middle connection part located below, and both ends of the third capacitor are respectively connected to the other end of the first middle connection strip and the other end of the second middle connection strip.

7. The compact omnidirectional broadband high-efficiency full-duplex dual antenna pair based on dipole antennas according to claim 1, characterized in that Both the first dielectric substrate and the second dielectric substrate are made of F4BM220 material, with a relative dielectric constant of 2.2 and a tangent of the loss angle of 0.

001.

8. The compact omnidirectional broadband high-efficiency full-duplex dipole antenna pair according to claim 1, characterized in that There is a first gap between the two Egyptian battle-axe dipoles, and they are symmetrically distributed left and right; each Egyptian battle-axe dipole includes a vertical arm and two top hat structures; the two top hat structures are respectively arranged at both ends of the vertical arm; a first slit is provided at the midpoint of the vertical arm; There is a second gap between the two feeding dipoles, and they are symmetrically distributed left and right; a second slit is provided at the midpoint of each feeding dipole; Both the first slit and the second slit coincide with the horizontal center line of the first dielectric substrate.

9. The compact omnidirectional broadband high-efficiency full-duplex dipole antenna pair according to claim 8, characterized in that, The rotation angle of the top hat structure of the Egyptian battle-axe dipole is 40°, the outer diameter and the inner diameter are 35 mm and 34 mm respectively, the lengths of both the first gap and the second gap are 51 mm, and the length of the first slit is 0.5 mm; the length of the second slit is 0.75 mm.

10. The compact omnidirectional broadband high-efficiency full-duplex dual antenna pair based on a dipole antenna according to claim 1, wherein, The lengths, widths and heights of the first dielectric substrate and the second dielectric substrate are 80 mm, 70.4 mm and 0.254 mm respectively, and the thicknesses of the copper layer on the upper surface of the first dielectric substrate, the copper layer on the lower surface of the second dielectric substrate, and the copper layer on the lower surface of the first dielectric substrate or the upper surface of the second dielectric substrate are all 0.017 mm.

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