Radiating patch and miniaturized multiband omnidirectional antenna

Abstract

The application relates to a radiation patch, which comprises a metal sheet and first and third grooves arranged on the metal sheet; a plurality of the first grooves are arranged in a ring array, the first grooves are semicircular structures, and the straight ends of the first grooves are communicated through a ring-shaped second groove; a plurality of the third grooves are arranged in a ring array, one end of each third groove points to the center of the second groove, and the other end is communicated with the inner ring of the second groove; each first groove is tangent to the outer ring of the second groove; the metal sheet is further provided with a plurality of fourth grooves arranged in a ring array, and the fourth grooves correspond to the first grooves one by one; one end of each fourth groove is communicated with the straight end of the corresponding first groove, and the other end is communicated with the outer ring of the second groove; two adjacent third grooves are further communicated through a fifth groove, and the fifth grooves are sequentially communicated to form a ring-shaped groove. The application can expand the bandwidth of an antenna, improve the omnidirectionality of the antenna and reduce the size of the antenna.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of communication antennas, in particular to a radiation patch and a miniaturized multi-band omnidirectional antenna. BACKGROUND

[0002] With the continuous progress of communication technology, the requirements for communication systems and devices are also getting higher and higher. Antennas are mainly used for transmitting and receiving signals and energy, and are a necessary component in communication systems. Traditional microstrip antennas face the challenge of complex communication environment. In order to adapt to the continuous development of communication technology, the antenna is also required to have better radiation performance characteristics. Traditional microstrip antennas have the disadvantages of narrow bandwidth and single frequency band. With the development of 5G / 6G wireless communication technology, the research direction of antennas mainly develops towards multi-band and miniaturization, in order to meet the demand of modern wireless communication environment for high frequency and wide bandwidth of large data transmission capacity and quality. The traditional microstrip antenna has not adapted to the actual application.

[0003] In summary, the main problems of the current traditional microstrip antenna are:

[0004] 1. The antenna has a large electrical size and a complex structure, resulting in high processing cost.

[0005] 2. The frequency band of the antenna is single, which cannot meet the demand of modern wireless communication for wide bandwidth and large data transmission capacity.

[0006] 3. The omnidirectionality of the antenna is poor, and it can only receive and send signals in a single direction, with limited coverage area and unable to receive signals from all directions.

[0007] How to design a microstrip antenna by a new method and improve the utilization and application ability of the antenna is an urgent problem to be solved at present. SUMMARY

[0008] Therefore, it is necessary to provide a radiation patch and a miniaturized multi-band omnidirectional antenna to expand the bandwidth of the antenna, improve the omnidirectionality of the antenna, and reduce the size of the antenna.

[0009] A radiation patch, comprising a metal sheet and a plurality of first grooves arranged in a ring array on the metal sheet, wherein each of the first grooves is a semi-elliptical structure, and the straight ends of the first grooves are communicated through a second groove.

[0010] A plurality of third grooves arranged in a ring array, wherein one end of each of the third grooves points to the center of the second groove, and the other end communicates with the inner ring of the second groove.

[0011] A plurality of third grooves arranged in a ring array, wherein one end of each of the third grooves points to the center of the second groove, and the other end communicates with the inner ring of the second groove.

[0012] In one embodiment, each of the first grooves is tangent to the outer ring of the second grooves.

[0013] In one embodiment, the metal sheet further comprises: a plurality of fourth grooves arranged in a ring array, and each of the fourth grooves corresponds to one of the first grooves.

[0014] One end of each of the fourth grooves is communicated with the straight end of the corresponding first groove, and the other end is communicated with the outer ring of the second grooves.

[0015] In one embodiment, two adjacent third grooves are further communicated through a fifth groove, and each of the fifth grooves is sequentially communicated to form a ring groove.

[0016] In one embodiment, two adjacent third grooves are communicated through a plurality of fifth grooves to form a plurality of ring grooves, and each of the ring grooves is arranged in layers.

[0017] In one embodiment, the size of the semi-elliptical structure is:

[0018] S=0.5πab

[0019] In the formula, S is the area of the semi-elliptical structure, π is the circular constant, a is the major axis of the semi-elliptical structure, and b is the minor axis of the semi-elliptical structure.

[0020] A miniaturized multi-band omnidirectional antenna comprises: a radiation patch, a dielectric substrate, a feed microstrip line, and a ground plate.

[0021] The radiation patch and the feed microstrip line are arranged on the front surface of the dielectric substrate, and the ground plate is arranged on the dielectric substrate.

[0022] The feed microstrip line is connected to one end of the radiation patch, and the feed microstrip line has a rectangular structure.

[0023] In one embodiment, the number of ground plates is two, and the two ground plates are symmetrically arranged on both sides of the feed microstrip line.

[0024] In one embodiment, the ground plate has a rectangular structure, and two adjacent edges of the ground plate are respectively coincident with two adjacent edges of the dielectric substrate.

[0025] In one embodiment, the gap between the feed microstrip line and the ground plate is in the range of 0.1mm-0.5mm.

[0026] The radiation patch and the miniaturized multi-band omnidirectional antenna can expand the bandwidth of the antenna, improve the omnidirectionality of the antenna and reduce the size of the antenna, solve the problems of single frequency band, poor omnidirectionality and large size of the traditional microstrip antenna, and meet the practical application of the microstrip antenna in wireless communication. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a schematic diagram of a radiation patch in an embodiment;

[0028] Figure 2 is a schematic diagram of a radiation patch in an embodiment;

[0029] Figure 3 is a schematic diagram of a radiation patch in an embodiment;

[0030] Figure 4 is a comparison diagram of S11 parameters in an embodiment;

[0031] Figure 5 is a comparison diagram of gain in an embodiment;

[0032] Figure 6 is a front view of a miniaturized multi-band omnidirectional antenna in an embodiment;

[0033] Figure 7 is a back view of a miniaturized multi-band omnidirectional antenna in an embodiment;

[0034] Figure 8 is a return loss curve diagram of a miniaturized multi-band omnidirectional antenna in an embodiment;

[0035] Figure 9 is an E-plane radiation pattern of a miniaturized multi-band omnidirectional antenna at 0.87 GHz in an embodiment;

[0036] Figure 10 is an H-plane radiation pattern of a miniaturized multi-band omnidirectional antenna at 0.87 GHz in an embodiment;

[0037] Figure 11 is an E-plane radiation pattern of a miniaturized multi-band omnidirectional antenna at 1.73 GHz in an embodiment;

[0038] Figure 12 is an H-plane radiation pattern of a miniaturized multi-band omnidirectional antenna at 1.73 GHz in an embodiment;

[0039] Figure 13 is an E-plane radiation pattern of a miniaturized multi-band omnidirectional antenna at 2.4 GHz in an embodiment;

[0040] Figure 14 H-plane radiation pattern at 2.4GHz for one embodiment of a miniaturized multi-band omni-directional antenna.

[0041] FIG. numbers:

[0042] Metal sheet 1, first slot 11, second slot 12, third slot 13, fourth slot 14, fifth slot 15, dielectric substrate 2, feed microstrip line 3, ground plate 4. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not used to limit the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts fall within the scope of protection of the present application.

[0044] It should be noted that all directionality indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative position relationship, movement condition, etc. between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the directionality indications also change accordingly.

[0045] In addition, the description such as "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple groups" is at least two groups, such as two groups, three groups, etc., unless otherwise specifically limited.

[0046] In the present application, unless otherwise specifically defined and limited, the terms "connection", "fixation" and the like should be understood in a broad sense, for example, "fixation" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection, or physical connection, or wireless communication connection; can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements or the interaction relationship between two elements, unless otherwise specifically limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0047] In addition, the technical solutions among the various embodiments of the present application can be combined with each other, but it must be based on the fact that a person skilled in the art can realize it, and when the combination of technical solutions appears contradictory or cannot be realized, it should be considered that the combination of technical solutions does not exist and is not within the protection scope required by the present application.

[0048] As shown in the drawings, Figure 1 The present application provides a radiation patch, which comprises a metal sheet 1 and is provided with the following on the metal sheet 1 in an embodiment:

[0049] A plurality of first grooves 11 arranged in a ring array, the first grooves 11 are semicircular structures, and the straight ends of each first groove 11 are communicated through a ring-shaped second groove 12; preferably, each first groove 11 is tangent to the outer ring of the second groove 12.

[0050] A plurality of third grooves 13 arranged in a ring array, one end of each third groove 13 points to the center of the second groove 12, and the other end communicates with the inner ring of the second groove 12.

[0051] As shown in the drawings, Figure 2 Preferably, the metal sheet 1 is further provided with: a plurality of fourth grooves 14 arranged in a ring array, and the fourth grooves 14 correspond one-to-one to the first grooves 11; one end of the fourth groove 14 communicates with the straight end of the corresponding first groove 11, and the other end communicates with the outer ring of the second groove 12.

[0052] As shown in the drawings, Figure 3 Further preferably, the two adjacent third grooves 13 are also communicated through a fifth groove 15, and each fifth groove 15 is sequentially connected to form a ring-shaped groove; the two adjacent third grooves 13 are communicated through a plurality of fifth grooves 15 to form a plurality of ring-shaped grooves, and each ring-shaped groove is nested layer by layer.

[0053] It should be noted that the straight end of the first groove 11 can be the major axis of the semicircular structure, or the minor axis.

[0054] In the present embodiment, the grooves (first groove, second groove, third groove, fourth groove and fifth groove) arranged in a ring array on the radiation patch are centrally symmetric and uniformly distributed, in the microwave band, this periodic groove (artificial electromagnetic structure) can support the electromagnetic mode of surface plasmon, which is a surface electromagnetic wave formed by the interaction of electromagnetic field and free electrons on the metal surface, which can break through the diffraction limit of electromagnetic wave, realize the subwavelength confinement of electromagnetic wave, significantly reduce the size of electromagnetic structure, and exhibit low loss characteristics, which is beneficial to realize the miniaturization and multi-band of microwave circuits, devices and systems.

[0055] Surface plasmons can excite localized surface wave modes on a metal sheet, confining electromagnetic waves to a grooved metal ring structure, significantly reducing the electrical size of the structure. Furthermore, by changing the geometry of the metal surface, its dispersion characteristics can be flexibly controlled, thereby obtaining miniaturized, multi-band microwave devices.

[0056] Unlike existing technologies that primarily utilize localized surface plasmons in the near field (mainly used in sensors, miniaturized resonators, filters, etc.), this application uses locally excited artificial surface plasmons to apply their far-field radiation characteristics to radiating patches in the field of microstrip antennas. This results in radiating patches possessing both excellent radiation and omnidirectional characteristics, and further, a miniaturized multi-band omnidirectional antenna based on artificial surface plasmons is designed.

[0057] The aforementioned radiating patch features grooves designed on a metal sheet, thereby exciting artificial surface plasmons. This expands the antenna's bandwidth, improves its omnidirectionality, and reduces its size, solving the problems of traditional microstrip antennas, such as limited bandwidth, poor omnidirectionality, and large size. Furthermore, the first groove has a semi-elliptical structure, which not only lowers the operating frequency and enables miniaturization but also further enhances the antenna's radiation capability and increases its gain, thus meeting the practical application requirements of microstrip antennas in wireless communication.

[0058] In one embodiment, the dimensions of the semi-elliptical structure are:

[0059] S = 0.5πab

[0060] In the formula, S is the area of ​​the semi-elliptical structure, π is pi, a is the major axis of the semi-elliptical structure, and b is the minor axis of the semi-elliptical structure.

[0061] The semi-elliptical structure can further reduce the antenna frequency while keeping the overall antenna size unchanged, thus further miniaturizing the antenna. This means that the I / λ (electrical size) can be further reduced, where I is the antenna size and λ is the antenna's operating wavelength. At the same time, it can also improve impedance matching and further increase the antenna's gain in the high-frequency band.

[0062] like Figure 4 The S11 parameter comparison chart shown is as follows: Figure 5 The gain comparison diagram shown demonstrates that the semi-elliptical structure in this application can improve the antenna gain and overall performance.

[0063] like Figure 6 to Figure 7 As shown, this application also provides a miniaturized multi-band omnidirectional antenna, including: a radiating patch, a dielectric substrate 2, a feed microstrip line 3, and a ground plane 4;

[0064] The radiation patch and the feeding microstrip line 3 are arranged on the front surface of the dielectric substrate 2, the feeding microstrip line 3 is connected to one end of the radiation patch, and the feeding microstrip line 3 has a rectangular structure.

[0065] The floor 4 is arranged on the dielectric substrate 2, and specifically, the floor 4 can be arranged on the front surface or the back surface of the dielectric substrate 2.

[0066] Specifically, the overall size of the antenna is 54mm*84mm*3.066mm, the thickness of the dielectric substrate is 3.048mm, and the material of the dielectric substrate is F4B, the dielectric constant of which is 2.94, and the loss tangent is 0.001.

[0067] The diameter of the metal sheet is 54.36mm, and the thickness is 0.018mm; the 1 / 2 elliptical structure of the first slot has a major axis diameter of 6mm, a minor axis diameter of 5mm, and an area of 47.12mm 2 ; the diameter of the second slot is 28mm, and the ring width is 2mm; the length of the third slot and the fourth slot is 8mm, which forms a periodic rectangular array slot with the center of the metal sheet as the origin and at an interval of 7.2°, and is arranged in a circle; the number of the first slot, the third slot and the fourth slot is not limited, and preferably, the number is 10-40, and further preferably, the number is 20.

[0068] The metal feeding microstrip line is used for feeding, and has a length of 29.11mm and a width of 7.38mm.

[0069] Preferably, the floor 4 is arranged on the front surface of the dielectric substrate 2, and the number of the floor 4 is two, and the two floors 4 are symmetrically distributed on both sides of the feeding microstrip line 3.

[0070] In one embodiment, the floor has a size of 23.31mm*27.95mm.

[0071] In this embodiment, the circular metal sheet with slots constitutes the radiation patch, the artificial surface plasmon mode of the radiation patch is excited to form multiple frequency bands, which is actually a standing wave mode, the microstrip line of the coplanar waveguide feed transmits electromagnetic waves, the electromagnetic waves are divided into two forward waves and reverse waves with the same frequency and opposite directions at the terminal of the microstrip line, the forward waves and the reverse waves meet each other after passing through the same path, and interfere with each other to form a standing wave, and the resonant frequency of the antenna and the circumference of the radiation patch satisfy the following relationship:

[0072] 2πR=n*λg

[0073] n=1,2,3……

[0074] In the formula, R is the radius of the circular radiation patch, n is the mode order (the mode order corresponds to the number of the type of electromagnetic mode corresponding to the resonance, and the larger the number, the higher the order, 1 is low order, and above 2 is high order), and λg is the operating wavelength (i.e., the wavelength of the electromagnetic wave) corresponding to the resonant frequency.

[0075] In the embodiment, the size of the antenna is smaller than that of the prior art; the feeding mode adopts a coplanar waveguide feeding, which is beneficial to enhancing the feeding efficiency and feeding effect of the antenna, reducing the signal loss of the feeding end, thereby increasing the gain and radiation efficiency of the antenna, and ensuring the reception quality of the signal; in combination with the structure of the artificial surface plasmon and the structure of the printed monopole antenna with the coplanar waveguide feeding, the effects of miniaturization, multi-band, high gain and omnidirectional radiation are realized; the excitation microstrip feeding is placed on the upper surface of the dielectric board to overcome the defect that the antenna gain is very small (such as 1.22dBi at about 2.4GHz) due to the serious dielectric loss of the existing antenna at a high frequency band, and the omnidirectionality is maintained.

[0076] The application is not limited to the specific shape of the floor 4, which can be a rectangular structure, an arc-shaped structure, etc.

[0077] Preferably, the floor 4 is of a rectangular structure, and two adjacent edges of the floor 4 coincide with two adjacent edges of the dielectric substrate 2.

[0078] Preferably, the gap between the feeding microstrip line 3 and the floor 4 is in the range of 0.1mm-0.5mm.

[0079] Further preferably, the gap between the feeding microstrip line 3 and the floor 4 is 0.3mm. At this time, the signal coupling effect is good, the antenna performance is good, and the process is easy to process.

[0080] In the embodiment, a corrugated metal resonant ring structure is formed by periodically grooving the circular radiation patch, the entire corrugated grooved metal ring circular radiation patch can effectively excite a local surface plasmon, and the coplanar waveguide feeding can effectively excite a local artificial surface plasmon. This local artificial surface plasmon is equivalent to a standing wave bound on the surface of the grooved metal structure, can form multiple different resonant modes, thereby realizing three operating frequency bands, generating three operating frequency points, and the three resonant frequency points being located at 0.875GHz, 1.735GHz and 2.42GHz, respectively, thereby forming a multi-band antenna, and the lowest order resonant mode being 0.87GHz, further reducing the electrical size of the antenna. The antenna has stable radiation performance, further excites the far-field characteristics, forms an omnidirectional radiation performance, and presents omnidirectionality at the three resonant frequency points, can receive signals from all directions, and can be applied in the fields of antennas, Internet of Things, etc. The application has the advantages of simple structure, easy manufacturing, low cost, stable radiation performance, and potential application in multiple fields of communication technology, and can be applied in the fields of wireless communication, Internet of Things, etc.

[0081] The present application carries out numerical verification by using electromagnetic simulation software CST, simulates and analyzes and optimizes the miniaturized multi-band omnidirectional antenna based on artificial surface plasmon, changes the structure form of the traditional printed monopole antenna, adds artificial surface plasmon structure, scans the parameters of the antenna structure to make the performance of the antenna optimal, and mainly analyzes and tests the impedance matching performance and bandwidth of the antenna by using the CST software, as shown in Figure 8 Figure 8 It can be seen from the return loss curve of the antenna that the antenna presents multi-band working characteristics (S11 <=-10dB), and the resonant frequency points are respectively 0.87GHz, 1.73GHz and 2.42GHz, the three working frequency bands are respectively 0.79-0.94GHz (150MHz), 1.55-1.86GHz (310MHz) and 2.27-2.48GHz (210MHz), and the antenna has obviously wider working bandwidth at each resonant mode; moreover, the S11 of each resonant frequency is below-25dB, the impedance matching performance of the antenna is better, and the quality factor is higher.

[0082] The radiation characteristics of the antenna are analyzed by the E-plane and H-plane patterns of each resonant frequency point, as shown in Figure 9 to Figure 14 The E-plane and H-plane patterns of the antenna designed by the present application at three resonant frequency points are provided, and it can be seen from the figure that the omnidirectionality of the antenna is good, the E-plane presents an 8-shaped pattern, and the H-plane presents a full circular pattern, which proves that the antenna is omnidirectional and can receive signals from all directions.

[0083] Specifically, Figure 9 the E-plane radiation pattern of 0.87GHz, Figure 10 the H-plane radiation pattern of 0.87GHz, and the gain is 0.676dBi; Figure 11 the E-plane radiation pattern of 1.73GHz, Figure 12 the H-plane radiation pattern of 1.73GHz, and the gain is 1.1dBi; Figure 13 the E-plane radiation pattern of 2.4GHz, Figure 14 the H-plane radiation pattern of 2.4GHz, and the gain is 2.94dBi.

[0084] ​In summary, the application performs periodic grooving on a circular radiation patch to form an artificial surface plasmon radiation structure, that is, a plasmon resonance structure. According to multiple resonance modes generated by surface electromagnetic waves bound on the periodically structured metal surface, the antenna generates multiple resonance operating frequency points, so that the antenna can cover multiple operating frequency bands, thereby forming a multi-band antenna, improving the ability to adapt to the environment, and effectively reducing the electrical size of the antenna. Using a coplanar waveguide feed, the feed loss is reduced, and the gain of the antenna is effectively improved. The antenna has stable radiation performance and good omnidirectionality in the operating frequency band range. The antenna has the advantages of simple structure, easy processing, low cost, multiple frequency bands, small size, stable antenna performance, good omnidirectionality, and can be applied to multiple communication fields such as antennas, Internet of Things, radars and the like.

[0085] The technical features of the above embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above embodiments are described, but as long as the combinations of the technical features do not contradict, they should be considered as falling within the scope of the present disclosure.

[0086] The above embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present application. It should be pointed out that, for ordinary skilled persons in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A radiation patch, characterized by, The metal sheet and the first groove arranged on the metal sheet comprise: A plurality of first grooves arranged in a ring array, the first grooves are semicircular structures, and the straight ends of each first groove are communicated through a ring-shaped second groove; A plurality of third grooves arranged in a ring array, one end of each third groove points to the center of the second groove, and the other end communicates with the inner ring of the second groove; The metal sheet further comprises: a plurality of fourth grooves arranged in a ring array, and the fourth grooves correspond to the first grooves one by one, and correspond to the third grooves one by one; one end of the fourth groove communicates with the straight end of the corresponding first groove, and the other end communicates with the outer ring of the second groove; The adjacent two third grooves are also communicated through a fifth groove, and each fifth groove is sequentially communicated to form a ring-shaped groove; The first groove, the second groove, the third groove, the fourth groove and the fifth groove arranged on the radiation patch and arranged in a ring array are centrally symmetrically and uniformly distributed; Periodic grooving is performed on the circular radiation patch to form an artificial surface plasmon radiation structure, so that the antenna can cover multiple working frequency bands to form a multi-band antenna.

2. The radiating patch of claim 1, wherein, The adjacent two third grooves are communicated through a plurality of fifth grooves to form a plurality of ring-shaped grooves, and each ring-shaped groove is sleeved layer by layer.

3. The radiating patch of any one of claims 1 or 2, wherein, The size of the semicircular structure is: ， wherein S is the area of the semi-elliptical structure, is the ratio of the circumference of a circle to its diameter, a is the major axis of the semi-elliptical structure, b is the minor axis of the semi-elliptical structure.

4. A miniaturized multi-band omni-directional antenna, characterized by, Comprise: The radiation patch, the dielectric substrate, the feed microstrip line and the ground plate according to any one of claims 1 to 3; The radiation patch and the feed microstrip line are arranged on the front surface of the dielectric substrate, and the ground plate is arranged on the dielectric substrate; The feed microstrip line is connected to one end of the radiation patch, and the feed microstrip line is a rectangular structure.

5. The compact multi-band omni-directional antenna according to claim 4, wherein, The number of the ground plate is two, and the two ground plates are symmetrically distributed on both sides of the feed microstrip line.

6. The miniaturized multi-band omni-directional antenna according to claim 5, characterized in that, The ground plate is a rectangular structure, and two adjacent edges of the ground plate coincide with two adjacent edges of the dielectric substrate.

7. The compact multi-band omni-directional antenna according to claim 6, wherein, The gap between the feed microstrip line and the ground plate is 0.1mm-0.5mm.

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