UWB antenna array

Abstract

The invention provides a UWB antenna array. The antenna array comprises: two antenna assemblies; wherein each antenna assembly comprises an annular monopole antenna and a microstrip feeder connected with the annular monopole antenna; the ground plane defect graph structure is arranged between the antenna assemblies; the ground plane defect pattern structures are symmetrically arranged relative to a center line between the two antenna assemblies; the ground plane defect pattern structure comprises at least one defect pattern branch and at least one slot hole, and the slot hole comprises at least one defect pattern branch. The antenna array provided by the invention can simultaneously meet the requirements of small antenna body distance, high isolation and relatively wide working bandwidth.

Description

Technical Field

[0001] The present invention relates to the technical field of antenna design, and in particular to a UWB antenna array. Background Art

[0002] With the vigorous development of wireless communication technology, ultra-wideband (UWB) wireless communication technology has gained wide attention for its advantages such as wide frequency band and low power consumption. In some cases, there is a need to measure the single-plane incident angle of the UWB system. In response to this demand, the UWB system calculates the incident angle by measuring the phase difference of the signal reaching each antenna in the array. The isolation between antennas directly affects the quality of the measured signal. At the same time, due to the high operating frequency of the UWB system, the half-wavelength required for the antenna spacing is relatively small. In this case, both the antenna body distance and high isolation are required, so there are high requirements for the design of the antenna array. At the same time, the small spacing also limits the size of the antenna body, which has a great impact on the working bandwidth of the antenna. Therefore, it is currently necessary to design an antenna array that can simultaneously meet the requirements of small antenna body distance, high isolation and wide working bandwidth. Summary of the invention

[0003] In order to at least partially solve the problems existing in the prior art, the present invention provides a UWB antenna array.

[0004] A UWB antenna array, the antenna array comprising: two antenna components; wherein each antenna component comprises a ring-shaped monopole antenna and a microstrip feeder connected to the ring-shaped monopole antenna; a ground plane defect pattern structure arranged between the antenna components; the ground plane defect pattern structure is symmetrically arranged relative to the midline between the two antenna components; and the ground plane defect pattern structure comprises at least one defect pattern branch and at least one slot, wherein the slot comprises at least one defect pattern branch.

[0005] Exemplarily, the defect pattern branch is a T-shaped ground plane defect pattern; the ground plane defect pattern structure includes a slot and three T-shaped ground plane defect pattern branches arranged outside the slot; wherein a T-shaped ground plane defect pattern branch is also arranged in the slot.

[0006] Exemplarily, the slot is a square slot; the square slot is used to achieve decoupling of a common signal path between the two antenna components; wherein the long axis of the square slot is parallel to the long axis of the microstrip feed line.

[0007] Exemplarily, the three T-shaped ground plane defect pattern branches are all arranged on the outer side of the first end of the square slot and are evenly distributed along the width direction of the square slot.

[0008] Exemplarily, a T-shaped ground plane defect pattern branch is arranged on the inner side of the second end of the square slot, and the T-shaped ground plane defect pattern branch is arranged in the center of the width direction of the square slot.

[0009] Exemplarily, the T-shaped ground plane defect pattern includes an axial portion, a transverse portion and two longitudinal portions; the axial portion is arranged at a fixed point outside the first end of the square slot and extends from the fixed point toward a target direction, the transverse portion is arranged perpendicularly relative to the axial portion to form a T-shaped structure with the axial portion, and the two longitudinal portions are respectively arranged on both sides of the transverse portion and parallel to the axial portion; wherein the target direction is parallel to the direction of the microstrip feeder toward the annular monopole antenna.

[0010] Exemplarily, the annular monopole antenna is a structure that is symmetrically folded inwardly to form an I-shaped cavity therein.

[0011] Exemplarily, the length of the annular monopole antenna is 3 mm, the width is 4 mm, and the width of a single side folded inward is 1.35 mm.

[0012] Exemplarily, the antenna array also includes a floor; in the floor, a V-shaped groove is arranged near the connection between the annular monopole antenna and the microstrip feeder; wherein the maximum width of the V-shaped groove is greater than the width of the annular monopole antenna and the microstrip feeder; the annular monopole antenna forms a larger bandwidth through the coupling of the annular graphic structure thereon with the V-shaped groove.

[0013] Exemplarily, the microstrip feed line runs through the length of the floor, and the length of the microstrip feed line is 16.2 mm.

[0014] The UWB antenna array provided by the present invention comprises two antenna components arranged at intervals, wherein each antenna component comprises a circular monopole antenna and a microstrip feeder connected to the circular monopole antenna. This arrangement of the antennas allows the two antennas to be close in distance and to achieve a larger working bandwidth, thereby simultaneously meeting the requirements of small size and wide bandwidth. At the same time, a ground plane defect pattern structure is arranged between the antenna components. The ground plane defect pattern structure is symmetrically arranged relative to the midline between the two antenna components. The ground plane defect pattern structure can improve the isolation between the dual antennas. Therefore, the antenna array provided by the present solution can simultaneously meet the requirements of small distance between antenna bodies, high isolation and wider working bandwidth.

[0015] A series of simplified concepts are introduced in the summary of the invention, which will be further described in detail in the detailed description. The summary of the invention does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the scope of protection of the claimed technical solution.

[0016] The advantages and features of the present invention are described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The following drawings of the present invention are used as part of the present invention for understanding the present invention. The embodiments of the present invention and their description are shown in the drawings to explain the principle of the present invention. In the drawings,

[0018] Figure 1 is a schematic structural diagram of an antenna array according to an exemplary embodiment of the present invention;

[0019] Figure 2 is a schematic structural diagram of an antenna array according to another exemplary embodiment of the present invention;

[0020] Figure 3 is a diagram showing simulation test results of an antenna array according to an exemplary embodiment of the present invention;

[0021] Figure 4 Schematic diagram of an antenna array radiation pattern according to an exemplary embodiment of the present invention.

[0022] The above drawings include the following reference numerals:

[0023] 10. Antenna assembly; 11. Ring monopole antenna; 12. Microstrip feed line; 13. Feeding point; 20. Ground plane defect pattern structure; 21. Defect pattern branch; 22. Slot; 30. Floor; 40. V-shaped groove. DETAILED DESCRIPTION

[0024] In the following description, a large amount of details are provided so that the present invention can be thoroughly understood. However, it will be appreciated by those skilled in the art that the following description only exemplarily illustrates a preferred embodiment of the present invention, and the present invention can be implemented without one or more such details. In addition, in order to avoid confusion with the present invention, some technical features well known in the art are not described in detail.

[0025] See also Figure 1 , providing a UWB antenna array. The antenna array provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0026] A UWB antenna array includes: two antenna components 10; each antenna component 10 includes a circular monopole antenna 11 and a microstrip feeder 12 connected to the circular monopole antenna 11; a ground plane defect pattern structure 20 is arranged between the antenna components 10; the ground plane defect pattern structure 20 is symmetrically arranged relative to the midline between the two antenna components 10; and the ground plane defect pattern structure 20 includes at least one defect pattern branch 21 and at least one slot 22, wherein the slot 22 includes at least one defect pattern branch 21.

[0027] The UWB system operates at a high frequency, so the half-wavelength required for antenna spacing is relatively small, so the spacing between antenna components needs to be reduced. Further, the antenna array includes two antenna components 10, and the spacing between antenna components 10 is small, which can meet the high operating frequency requirements of the UWB system.

[0028] Exemplarily, the loop-shaped monopole antenna 11 is a MIMO (Multiple-inMultiple-out) type antenna. MIMO is a radio antenna technology that uses multiple antennas at the transmitter and receiver to provide multiple signal paths to carry data. MIMO can achieve beamforming, transmit diversity and receive diversity.

[0029] Exemplarily, the ring monopole antenna 11 is a structure that is folded inwardly and symmetrically to form an I-shaped cavity inside. The folded structure of the antenna can reduce the size of the antenna and meet the small size requirements of the antenna array. Of course, the ring monopole antenna 11 can also be other folded structures such as folded in half.

[0030] Exemplarily, the length of the annular monopole antenna 11 is 3 mm, the width is 4 mm, and the width of a single side folded inward is 1.35 mm.

[0031] Exemplarily, the annular monopole antenna 11 is connected to a microstrip feeder 12 to achieve transmission of antenna signals. The microstrip feeder 12 may have a relatively long length to improve the flexibility of antenna array signal transmission.

[0032] The antenna array may also include a ground 30. The antenna assembly 10 may be stacked on the ground 30. Further, the microstrip feeder 12 runs through the length of the ground 30, and the length L1 of the microstrip feeder is 16.2 mm and the width W1 is 3.3 mm. Such a configuration allows the microstrip feeder 12 to have a feeding point 13 at the end thereof to be connected to the system RF routing outside the antenna array.

[0033] For example, the floor 30 can be structurally changed to form a DGS (Defected Ground Structure). The design of the defective ground structure can make the isolation between antennas higher, so as to reduce the phase interference of system measurement and increase the angle measurement accuracy. At the same time, because the reference ground plane under the antenna body is relatively complete, the antenna body is not affected by other metal objects under the antenna, and the characteristic of being able to be deployed close to other objects is achieved.

[0034] Exemplarily, DGS is a ground plane defect pattern structure arranged between antenna components and is symmetrically arranged relative to the midline between the antenna components. It can effectively balance the two antenna components while isolating the two antenna components, thereby ensuring the directivity of the antenna array.

[0035] Exemplarily, the antenna array as a whole may be a symmetrical structure, that is, the antenna components and the ground plane defect pattern structure are symmetrical about a certain straight line.

[0036] Exemplarily, the ground plane defect pattern structure 20 includes at least one defect pattern branch 21 and at least one slot 22. The defect pattern branches 21 may be odd or even. The defect pattern branches 21 may be symmetrically arranged between the two antenna components. The slots 22 may be odd or even. The slots 22 may also be symmetrically arranged between the two antenna components. Further, the defect pattern branches 21 are connected to the slots 22 to improve the isolation between the antenna components as a whole. Exemplarily, the defect pattern branches 21 may be T-shaped, triangular, or other structures.

[0037] Exemplarily, in the floor 30, a V-slot 40 (V-slot) is provided adjacent to the connection between the annular monopole antenna 11 and the microstrip feeder 12; wherein the maximum width of the V-slot 40 is greater than the width of the annular monopole antenna 11 and the microstrip feeder 12; the annular monopole antenna 11 forms a larger bandwidth through the coupling of the annular graphic structure thereon with the V-slot 40. The operating bandwidth of the antenna is defined as a set of frequency points within which the antenna space and circuit parameter performance are within the required limits defined by the user. With this arrangement, the operating bandwidth of the antenna array is relatively high, meeting the requirements of angle measurement. In other embodiments, the slot may also be in other shapes such as U-shaped, rectangular, etc. The embodiments of the present application do not limit the specific shape of the slot.

[0038] Exemplarily, the substrate of the antenna array is FR4, which has a relative dielectric constant of 4.4, a dielectric loss angle of 0.02, and a total thickness of 1.6 mm.

[0039] Exemplarily, after the antenna array design parameters are optimized, the generated antenna array design is printed on a circuit board for manufacturing. The manufactured antenna array can be used for single-plane incident angle measurement of a UWB system in a small device.

[0040] The UWB antenna array provided by the present invention includes two antenna components arranged at intervals, wherein each antenna component includes a circular monopole antenna and a microstrip feeder connected to the circular monopole antenna. This arrangement of the antennas allows the two antennas to be close in distance and achieve a larger working bandwidth, which can simultaneously meet the requirements of small size and wide bandwidth; at the same time, a ground plane defect pattern structure is arranged between the antenna components; the ground plane defect pattern structure is symmetrically arranged relative to the midline between the two antenna components; the isolation between the dual antennas can be improved by the ground plane defect pattern structure, therefore, the antenna array provided by this solution can simultaneously meet the requirements of small antenna body distance, high isolation and wide working bandwidth. The antenna array that meets the above requirements can reliably measure the single-plane incident angle of the UWB system in a small device.

[0041] For example, Figure 1 As shown, the defect pattern branch 21 is a T-shaped ground plane defect pattern (T-shaped branch); the ground plane defect pattern structure 20 includes a slot 22 and three T-shaped ground plane defect pattern branches 21 arranged outside the slot 22; wherein a T-shaped ground plane defect pattern branch 21 is also arranged in the slot 22. The three T-shaped ground plane defect pattern branches 21, the slot 22, and the T-shaped ground plane defect pattern branch 21 in the slot 22 are all symmetrically arranged about the midline between the two antenna components. Further, the three T-shaped ground plane defect pattern branches 21 and the T-shaped ground plane defect pattern branch 21 in the slot 22 can be structures with the same shape and size. Furthermore, the width of the inner side of the slot 22 can be 7.7 mm, which is larger than the size of the T-shaped ground plane defect pattern branch 21.

[0042] Exemplarily, the slot 22 is a rectangular slot; the rectangular slot is used to achieve decoupling of a shared signal path between two antenna assemblies 10; wherein the long axis of the rectangular slot is parallel to the long axis of the microstrip feed line 12.

[0043] Exemplarily, the three T-shaped ground plane defect pattern branches 21 are all arranged outside the first end of the square slot and are evenly distributed along the width direction of the square slot, wherein the width direction of the square slot can be parallel to the line between the midpoints of the two antenna components.

[0044] Exemplarily, a T-shaped ground plane defect pattern branch 21 is disposed on the inner side of the second end of the square slot, and the T-shaped ground plane defect pattern branch 21 is disposed in the center in the width direction of the square slot.

[0045] The symmetrical structure of the square slot and the T-shaped ground plane defect pattern branch 21 can effectively balance the two antenna components while isolating the two antenna components, thereby ensuring the directivity of the antenna array.

[0046] Exemplarily, the T-shaped ground plane defect pattern includes an axis portion, a transverse portion, and two longitudinal portions; the axis portion is arranged at a fixed point outside the first end of the square slot and extends from the fixed point to a target direction, the transverse portion is arranged perpendicularly relative to the axis portion to form a T-shaped structure with the axis portion, and the two longitudinal portions are arranged on both sides of the transverse portion and are parallel to the axis portion; wherein the target direction is parallel to the direction of the microstrip feeder 12 toward the annular monopole antenna 11. Exemplarily, the side of the fixed point can be aligned with the extension direction of the side of the square slot.

[0047] In the above embodiment, the ground plane defect pattern structure 20 includes three T-shaped branches and a square slot with a T-shaped branch, which is used for decoupling the shared signal path between the dual antennas.

[0048] For example, Figure 2 The following are examples of the dimensions of the antenna array. D1 = 15.6, D2 = 0.7, D3 = 2.6, D4 = 5.0, L = 20.0, L1 = 16.2, L2 = 3.0, L3 = 1.3, L4 = 0.3, L5 = 1.9, L6 = 2.3, L7 = 14.6, W = 50, W1 = 3.3, W2 = 4.0, W3 = 0.4, W4 = 1.3, W5 = 2.6, W6 = 0.5, W7 = 7.7. The units of these dimensions are all mm.

[0049] like Figure 3 As shown, Figure 2 The simulated S-parameters and realized gain of the antenna array at different frequencies. 11 |. Based on this result, it can be determined that the antenna array achieves the gain of the proposed antenna. Moreover, in the frequency band range of 7.7 to 14.3 GHz, the simulated |S 11 | is less than -10dB, and the relative bandwidth formed is about 60%, that is, the antenna array achieves a wide working bandwidth. The simulated gain in the required working frequency band is about 4dBi. That is, the working frequency range of the antenna array is 7.7 to 14.3GHz. At the same time, the isolation between the two antennas is greater than 25dB in the entire working band. In addition, Figure 4 As shown, Figure 4(a), (b) and (c) show the radiation patterns of different antennas in the XOZ and YOZ directions respectively. The radiation pattern of the antenna shows that the gain directly above the flat antenna is relatively average and the directivity is good. Both simulation and measurement show that the antenna array provided by the present invention is easy to integrate into the circuit board, and its isolation is significantly better than that of the ordinary microstrip line antenna array.

[0050] Therefore, according to the dual antenna array in the form described in the present invention, it is possible to achieve a planar incident angle measurement application suitable for UWB systems with high isolation, frequency range and stable radiation pattern. Due to its overall size and processing materials, it has a wide range of applicable characteristics such as low cost, small size and anti-interference, and is particularly suitable for the application of UWB systems for high incident angle measurement accuracy equipment. At the same time, this design also has the characteristics of being able to be deployed close to other objects because the reference ground plane under the antenna body is intact and is not affected by other metal objects under the antenna.

[0051] In the description of the present invention, it is necessary to understand that the orientation or positional relationship indicated by directional words such as "front", "back", "up", "down", "left", "right", "lateral", "longitudinal", "vertical", "horizontal", "top", "bottom", etc. is usually 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. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present invention; the directional words "inside" and "outside" refer to the inside and outside relative to the contour of each component itself.

[0052] For ease of description, regional relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the regional positional relationship between one or more components or features shown in the figure and other components or features. It should be understood that regional relative terms include not only the orientation of the components as described in the figure, but also different orientations in use or operation. For example, if the components in the accompanying drawings are inverted as a whole, the components "above other components or features" or "above other components or features" will include the situation where the components are "below other components or structures" or "below other components or structures". Therefore, the exemplary term "above" may include both "above" and "below". In addition, these components or features may also be positioned at other different angles (e.g., rotated 90 degrees or other angles), and this article is intended to include all of these situations.

[0053] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, parts, components and / or combinations thereof.

[0054] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein.

[0055] The present invention has been described by the above embodiments, but it should be understood that the above embodiments are only for the purpose of example and description, and are not intended to limit the present invention to the scope of the described embodiments. In addition, it can be understood by those skilled in the art that the present invention is not limited to the above embodiments, and more variations and modifications can be made according to the teachings of the present invention, and these variations and modifications all fall within the scope of the protection claimed by the present invention. The protection scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A UWB antenna array, characterized in that: include: Two antenna assemblies; wherein each antenna assembly comprises a ring monopole antenna and a microstrip feeder connected to the ring monopole antenna; A ground plane defect pattern structure is arranged between antenna components; the ground plane defect pattern structure is symmetrically arranged relative to the midline between the two antenna components; and the ground plane defect pattern structure includes at least one defect pattern branch and at least one slot, wherein the slot includes at least one defect pattern branch.

2. The UWB antenna array according to claim 1, wherein the defect pattern branch is a T-shaped ground plane defect pattern; The ground plane defect pattern structure comprises a slot and three T-shaped ground plane defect pattern branches arranged outside the slot; wherein a T-shaped ground plane defect pattern branch is also arranged in the slot.

3. The UWB antenna array according to claim 2, characterized in that: The slot is a square slot; the square slot is used to achieve decoupling of a shared signal path between the two antenna components; Wherein, the long axis of the square slot is parallel to the long axis of the microstrip feed line.

4. The UWB antenna array according to claim 3, characterized in that: The three T-shaped ground plane defect pattern branches are all arranged on the outer side of the first end of the square slot and are evenly distributed along the width direction of the square slot.

5. The UWB antenna array according to claim 4, characterized in that: A T-shaped ground plane defect pattern branch is arranged on the inner side of the second end of the square slot, and the T-shaped ground plane defect pattern branch is arranged in the center in the width direction of the square slot.

6. The UWB antenna array according to claim 4, characterized in that: The T-shaped ground plane defect pattern comprises an axial portion, a transverse portion and two longitudinal portions; The shaft portion is arranged at a fixed point outside the first end of the square slot and extends from the fixed point toward a target direction, the transverse portion is arranged perpendicularly relative to the shaft portion to form a T-shaped structure with the shaft portion, and the two longitudinal portions are respectively arranged on both sides of the transverse portion and parallel to the shaft portion; wherein the target direction is parallel to the direction of the microstrip feeder toward the annular monopole antenna.

7. The UWB antenna array according to any one of claims 1 to 6, characterized in that: The annular monopole antenna is a structure that is folded inwardly and symmetrically to form an I-shaped cavity inside.

8. The UWB antenna array according to claim 7, characterized in that: The length of the annular monopole antenna is 3 mm, the width is 4 mm, and the width of a single side folded inward is 1.35 mm.

9. The UWB antenna array according to any one of claims 1 to 6, characterized in that: The antenna array also includes a floor; In the floor, a V-shaped groove is provided near the connection between the annular monopole antenna and the microstrip feeder; wherein the maximum width of the V-shaped groove is greater than the width of the annular monopole antenna and the microstrip feeder; the annular monopole antenna forms a larger bandwidth through the coupling of the annular graphic structure thereon with the V-shaped groove.

10. The UWB antenna array according to claim 9, characterized in that: The microstrip feed line runs through the length of the floor, and the length of the microstrip feed line is 16.2 mm.

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