Directional antenna and electronic device

Abstract

The application relates to the technical field of antennas, and provides a directional antenna and an electronic device, the directional antenna comprising a reflecting plate, a dielectric substrate arranged on the reflecting plate, and at least one slot antenna array arranged on the dielectric substrate, the dielectric substrate having a first surface and a second surface arranged oppositely; the slot antenna array is arranged on the first surface of the dielectric substrate, and the slot antenna array comprises a plurality of radiation units arranged in an array, each radiation unit comprising a first slot and a second slot arranged oppositely in parallel, and a third slot connected between the first slot and the second slot. The application not only has low manufacturing cost, but also can improve the gain of the directional antenna by improving the structure of the radiation unit.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and more particularly to a directional antenna and electronic device. Background Technology

[0002] As the carrier of information transmission and reception in a wireless communication system, the antenna is one of the key components of the system, and its performance directly affects the technical specifications of the wireless communication system.

[0003] Among the many types of antennas, directional antennas have many advantages over other types. Directional antennas are used to receive signals from a source in a specific direction or to transmit signals in a specific direction. Gain is the most fundamental factor determining the performance of a directional antenna; high gain helps conserve the energy required for signal transmission.

[0004] In related technologies, especially in a series of wireless products such as wireless bridges, the requirements for antennas are quite special. High-gain directional antennas are needed for long-distance point-to-point communication. Therefore, there is an urgent need to provide a directional antenna with high gain. Summary of the Invention

[0005] The first aspect of the present invention provides a directional antenna to overcome at least one of the above-mentioned technical defects in the prior art, which not only has low manufacturing cost, but also improves the gain of the directional antenna by improving the structure of the radiating element.

[0006] A second aspect of the present invention provides an electronic device.

[0007] A first aspect of the present invention provides a directional antenna, comprising a reflector, a dielectric substrate disposed on the reflector, and at least one slot antenna array disposed on the dielectric substrate, wherein:

[0008] The dielectric substrate has a first surface and a second surface disposed opposite to each other;

[0009] The slot antenna array is disposed on the first surface of the dielectric substrate. The slot antenna array includes a plurality of radiating elements arranged in an array. Each radiating element includes a first slot and a second slot arranged in parallel with each other. A third slot connects the first slot and the second slot.

[0010] According to a directional antenna provided by the present invention, a radiating groove is connected to one side of the first slot and / or the second slot, the radiating groove being located on the side of the first slot or the second slot away from the third slot.

[0011] According to a directional antenna provided by the present invention, the radiating slot has a first radiating edge and a second radiating edge disposed opposite to each other;

[0012] The first radiating edge and the second radiating edge are arranged at an angle to each other, the first ends of the first radiating edge and the second radiating edge are connected to each other, and the second ends of the first radiating edge and the second radiating edge are both connected to the side of the first gap or the second gap.

[0013] According to a directional antenna provided by the present invention, the distance between the second end of the first radiating edge and the second end of the second radiating edge is less than the length of the side of the first slot or the second slot.

[0014] According to a directional antenna provided by the present invention, a third radiating edge is connected between the first end of the first radiating edge and the second end of the second radiating edge;

[0015] The third radiating edge is parallel to the side of the first gap or the second gap, and the first radiating edge, the second radiating edge and the third radiating edge together form a virtual trapezoidal structure.

[0016] According to the present invention, a directional antenna further includes a microstrip feeder assembly for feeding the directional antenna, the microstrip feeder assembly including a plurality of microstrip feeder wires, the position of each microstrip feeder wire corresponding one-to-one with the position of each radiating element;

[0017] The two adjacent microstrip feed lines are arranged opposite each other, and the two adjacent microstrip feed lines are connected by a branch transmission line. The two adjacent branch transmission lines are connected by a trunk transmission line, and the trunk transmission line is provided with a power supply interface.

[0018] According to a directional antenna provided by the present invention, the branch transmission line and the trunk transmission line are connected by an impedance matching stub.

[0019] According to a directional antenna provided by the present invention, the reflector is disposed on one side of the second surface of the dielectric substrate, and a gap is left between the reflector and the second surface of the dielectric substrate.

[0020] According to a directional antenna provided by the present invention, a plurality of radiating elements arranged in an array are disposed on a patch body, and the spacing between two adjacent radiating elements is 30mm to 40mm;

[0021] The length of the dielectric substrate is 120mm to 160mm, and the width of the dielectric substrate is 30mm to 50mm.

[0022] A second aspect of the present invention provides an electronic device, including a device body and a directional antenna as described in any of the preceding claims, wherein the directional antenna is applied to the device body.

[0023] The directional antenna provided by this invention comprises a reflector on one side of a dielectric substrate and at least one slot antenna array on the other side. This slot antenna array includes multiple radiating elements arranged in an array. Each radiating element includes a first slot and a second slot arranged relatively parallel to each other, with a third slot connecting the first and second slots. By improving the structure of the radiating elements, the gain of the directional antenna can be increased, and it can also adapt to different transmission environments, enabling dual-band switching transmission, i.e., switching between the 2.4GHz and 5GHz frequency bands. For example, in urban areas where 2.4GHz interference is severe, the 5GHz band can be selected to improve communication stability, while in suburban areas where wireless interference is less, the 2.4GHz band can be used to ensure a longer transmission distance.

[0024] Furthermore, at least one side of the first and second slits is connected to a radiating slot, which is located on the side of the first or second slit facing away from the third slit. This is equivalent to protruding the first slit outwards to form a radiating slot, making the area of ​​the improved first slit larger than the area of ​​the original first slit; or protruding the second slit outwards to form a radiating slot, making the area of ​​the improved second slit larger than the area of ​​the original second slit; or simultaneously protruding the first and second slits outwards to form radiating slots respectively. In this way, multiple spacings are formed in the first or second slit, each corresponding to a different frequency point, thereby effectively expanding the bandwidth of the directional antenna and improving its gain. Moreover, the directional antenna structure provided by this invention is relatively compact, easy to process, and has a low manufacturing cost.

[0025] The electronic device provided by the present invention, having the aforementioned directional antenna, possesses all the advantages described above. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the structure of the directional antenna provided in an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the structure of a single radiating element in a directional antenna provided in an embodiment of the present invention;

[0029] Figure 3 This is one of the front views of the dielectric substrate in the directional antenna provided in the embodiments of the present invention;

[0030] Figure 4 This is a second front view of the dielectric substrate in the directional antenna provided in this embodiment of the invention;

[0031] Figure 5 This is a rear view of the dielectric substrate in the directional antenna provided in an embodiment of the present invention;

[0032] Figure 6 yes Figure 1 The frequency response diagram of the reflection parameters of the directional antenna is shown.

[0033] Figure 7 yes Figure 1 The far-field radiation pattern (5.2 GHz) of the directional antenna shown;

[0034] Figure 8 yes Figure 1 The antenna center gain-frequency response diagram for the directional antenna from 5.0 GHz to 5.8 GHz is shown (radiation direction is: );

[0035] Figure 9 yes Figure 1 The far-field radiation pattern (2.44 GHz) of the directional antenna shown;

[0036] Figure 10 yes Figure 1 The diagram shows the antenna center gain-frequency response from 2.40 GHz to 2.48 GHz for the directional antenna shown (radiation direction is: );

[0037] Figure 11 This is a schematic diagram of the directional antenna structure before the improvement of the embodiment of the present invention;

[0038] Figure 12 This is a comparison diagram of the reflection parameters and frequency characteristics of the directional antenna before the improvement of the embodiment of the present invention;

[0039] Figure 13 This is a diagram showing the 2.44GHz gain effect of the directional antenna before the improvement in this embodiment of the invention;

[0040] Figure 14 This is a graph showing the 5.2GHz gain effect of the directional antenna before the improvement in this embodiment of the invention.

[0041] Figure label:

[0042] 100. Dielectric substrate; 101. Connecting hole;

[0043] 200, Patch body; 201, Radiation unit; 2011, First gap; 2012, Second gap; 2013, Third gap; 2014, Radiation slot; 2014-1, First radiation edge; 2014-2, Second radiation edge; 2014-3, Third radiation edge;

[0044] 300. Microstrip feeder assembly; 301. Microstrip feeder line; 302. Branch transmission line; 303. Trunk transmission line; 304. Impedance matching stub;

[0045] 400. Reflector. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0047] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.

[0048] In the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0049] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0050] With the development of wireless communication technology, the popularization of wireless networks, and the diversification of application scenarios, WIFI technology is also constantly developing and improving.

[0051] Currently, most wireless products use single-band 2.4GHz Wi-Fi for wireless transmission, such as wireless mice, wireless keyboards, USB wireless network adapters, and wireless routers. 2.4GHz wireless transmission offers relatively good penetration and a relatively long coverage distance; however, its widespread availability makes it susceptible to interference from other devices. In this context, the 5GHz band offers a cleaner channel and faster speeds, but its signal penetration is weaker than the 2.4GHz band, limiting its coverage area.

[0052] Combining the advantages and disadvantages of the two frequency bands mentioned above, namely the 2.4GHz band and the 5GHz band, dual-band WIFI devices that combine the two bands can not only provide good wireless connectivity, but also achieve good indoor and outdoor signal coverage and higher bandwidth. They play a more powerful role in wireless networks, serving multiple purposes such as data transmission, network connectivity, and security protection, bringing users a better wireless experience.

[0053] The most important medium for wireless communication is the antenna used to transmit and receive electromagnetic signals. Designing a high-performance dual-band antenna for dual-band Wi-Fi devices is one of the key factors that determines the communication performance of the device.

[0054] Commonly used Wi-Fi antennas can be categorized by their operating frequency into single-band antennas (only operating in the 2.4GHz or 5GHz band) and dual-band antennas (supporting both 2.4GHz and 5GHz bands simultaneously). They can also be classified by their radiation range into omnidirectional antennas and directional antennas. The form factor of the antenna varies depending on the application scenario. With the advent of the Internet of Things era, the demand for network performance is increasing, and multi-band, high-gain, and miniaturization are becoming the trends for antennas, especially in wireless routers, wireless bridges, wireless cameras, and other wireless products. Wireless bridges, in particular, have unique antenna requirements, needing to use high-gain directional antennas for long-distance point-to-point communication.

[0055] From the perspective of antennas, the amplitude of the antenna's scattering parameters (S-parameters) reflects the magnitude of the power loss of the input antenna. Generally speaking, the frequency range where S11 < -10dB is defined as the antenna's working bandwidth (also known as the resonant frequency band). The smaller S11 is than -10dB, the higher the antenna gain will be, and the farther the transmission distance will be under the same conditions.

[0056] Therefore, for the needs of long-distance dual-band communication, its operating bandwidth can fully cover both frequency bands (2.40-2.48GHz or 5.0GHz-5.8GHz), that is, within the 2.40-2.48GHz and 5.0GHz-5.8GHz frequency bands, the antenna gain S11 < -10dB. The smaller the value of S11, the higher the antenna gain. Therefore, this invention provides a directional antenna, mainly used in wireless devices for long-distance (3km or 5km) point-to-point communication, such as wireless bridges.

[0057] Figure 1 This is a schematic diagram of the structure of the directional antenna provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a single radiating element in a directional antenna provided in an embodiment of the present invention.

[0058] See Figure 1 and Figure 2 This invention provides a directional antenna, which includes a dielectric substrate 100, a slot antenna array, a reflector 400, and a microstrip feed assembly 300. The dielectric substrate 100 is disposed on the reflector 400, and the slot antenna array is disposed on the dielectric substrate 100.

[0059] The dielectric substrate 100 is the main support structure for supporting and fixing the slot antenna array, the reflector 400, and the microstrip feed assembly 300. The dielectric constant and size of the dielectric substrate 100 have a certain influence on the frequency and radiation direction of the directional antenna.

[0060] In some embodiments of the present invention, the dielectric substrate 100 may be an FR-4 board with a length of 120mm to 160mm and a width of 30mm to 50mm, and the cross-sectional thickness of the dielectric substrate 100 is less than 2mm. The FR-4 board is a double-sided copper-clad PCB board made of epoxy resin and glass cloth laminated together. The dielectric constant of commonly used PCB boards relative to air is 4.2-4.7. The dielectric constant of the FR-4 board changes with temperature, and its maximum variation can reach 20% within the temperature range of 0-70 degrees Celsius. Changes in the dielectric constant can lead to a 10% change in circuit delay; the higher the temperature, the greater the delay. The dielectric constant also changes with signal frequency; the higher the frequency, the lower the dielectric constant. The classic value of the dielectric constant of the FR-4 board is 4.4. The dielectric substrate 100 may also be a general-purpose printed circuit board (PCB) board with uniform dielectric constant and a basically consistent thickness.

[0061] The shape of the dielectric substrate 100 is not specifically limited and can be circular, rectangular, square, etc. In this embodiment of the invention, a rectangular dielectric substrate 100 is used as an example for description. The dielectric substrate 100 has a first surface and a second surface arranged back to back, that is, the first surface and the second surface are located on opposite sides of the dielectric substrate 100.

[0062] The slot antenna array is disposed on a patch body 200, which is located on the first surface of the dielectric substrate 100. The length of the patch body 200 can be the same as the length of the dielectric substrate 100, i.e., 120mm to 160mm; the width of the patch body 200 can be the same as the width of the dielectric substrate 100, i.e., 30mm to 50mm. The slot antenna array includes multiple radiating elements 201 arranged in an array. Each radiating element 201 includes a first slot 2011 and a second slot 2012 arranged relatively parallel to each other. A third slot 2013 connects the first slot 2011 and the second slot 2012.

[0063] Furthermore, a radiation groove 2014 is connected to one side of at least one of the first gap 2011 and the second gap 2012, and the radiation groove 2014 is located on the side of the first gap 2011 or the second gap 2012 that is away from or far away from the third gap 2013.

[0064] That is, the radiation groove 2014 can be connected to the side of the first gap 2011 away from the third gap 2013, and the radiation groove 2014 is connected to the first gap 2011, which is equivalent to increasing the area of ​​the first gap 2011.

[0065] The radiation slot 2014 can also be connected to the side of the second slot 2012 away from the third slot 2013. The radiation slot 2014 is connected to the second slot 2012, which is equivalent to increasing the area of ​​the second slot 2012.

[0066] The radiation slot 2014 can also be connected to the side of the first slot 2011 away from the third slot 2013 and the side of the second slot 2012 away from the third slot 2013 at the same time. This is equivalent to the first slot 2011 and the second slot 2012 expanding in the direction away from the third slot 2013 at the same time. That is, the area of ​​the first slot 2011 and the second slot 2012 both increase compared to before the improvement.

[0067] The microstrip feed assembly 300 is used to feed the directional antenna. After the dimensions of the dielectric substrate 100 and the radiating element 201 are determined, the microstrip feed assembly 300 converts the overall output impedance of the directional antenna of this embodiment into a standard impedance of 50Ω.

[0068] In this embodiment of the invention, the patch body 200 and the microstrip feed assembly 300 are disposed back-to-back on opposite sides of the dielectric substrate 100. When the directional antenna is in operation, it utilizes the radiating element 201 of the patch body 200 to leak electromagnetic waves, achieving radiation and reception functions through the electromagnetic field distribution on the dielectric substrate 100. When the directional antenna receives an electromagnetic wave signal, the patch body 200 generates an induced current, thereby converting the signal into an electrical signal output. When the directional antenna transmits a signal, the patch body 200 generates a current, thereby radiating electromagnetic waves.

[0069] It is understood that the directional antenna provided in this embodiment of the invention, by setting a reflector 400 on one side of the dielectric substrate 100 and setting at least one slot antenna array on the other side of the dielectric substrate 100, includes a plurality of radiating elements 201 arranged in an array. Each radiating element 201 includes a first slot 2011 and a second slot 2012 arranged in parallel, and a third slot 2013 connects the first slot 2011 and the second slot 2012. By improving the structure of the radiating elements, the gain of the directional antenna can be improved, and it can also adapt to different transmission environments to achieve dual-band switching transmission, that is, switching between the 2.4GHz band and the 5GHz band. For example, in urban areas where the 2.4GHz band has severe interference, the 5GHz band is selected to improve communication stability, while in suburban areas where there is less wireless interference, the 2.4GHz band is used to ensure a longer transmission distance.

[0070] Furthermore, a radiating slot 2014 is connected to one side of at least one of the first slot 2011 and the second slot 2012. The radiating slot 2014 is located on the side of the first slot 2011 or the second slot 2012 opposite to the third slot 2013. This is equivalent to protruding the first slot 2011 outward to form the radiating slot 2014, making the area of ​​the improved first slot 2011 larger than the area of ​​the original first slot 2011; or protruding the second slot 2012 outward to form the radiating slot 2014, making the area of ​​the improved second slot 2012 larger than the area of ​​the original second slot 2012; or simultaneously protruding the first slot 2011 and the second slot 2012 outward to form radiating slots 2014 respectively. In this way, multiple spacings are formed in the first slot 2011 or the second slot 2012, and these multiple spacings correspond to multiple different frequency points, thereby effectively expanding the bandwidth of the directional antenna and improving its gain. Furthermore, the directional antenna structure provided by this invention is relatively compact, easy to process, and has a low manufacturing cost.

[0071] Continue reading Figure 1 and Figure 2 Based on the above embodiments, the directional antenna provided in this embodiment of the invention has a radiating slot 2014 with a first radiating edge 2014-1 and a second radiating edge 2014-2 arranged opposite to each other. The first radiating edge 2014-1 and the second radiating edge 2014-2 are arranged at an angle to each other, which can be understood as being greater than 0° and less than 90°. For example, the angle can be 15°, 20°, 25°, 30°, 35°, 45°, or 60°, etc. The first ends of the first radiating edge 2014-1 and the second radiating edge 2014-2 are connected to each other, and the second ends of both the first radiating edge 2014-1 and the second radiating edge 2014-2 are connected to the side of the first slot 2011 or the second slot 2012.

[0072] Essentially, the first radiating edge 2014-1 and the second radiating edge 2014-2 together form a virtual triangular structure. That is, when the radiating slot 2014 is located on the side of the first slot 2011 away from the third slot 2013, a triangular region is formed between the first radiating edge 2014-1, the second radiating edge 2014-2, and the extended side lines of the first slot 2011. Thus, multiple spacings are formed within the first slot 2011, each corresponding to a different frequency point, effectively expanding the bandwidth of the directional antenna and improving its gain.

[0073] When the radiation groove 2014 is located on the side of the second gap 2012 away from the third gap 2013, the structural configuration of the radiation groove 2014 is the same as that of the radiation groove 2014 located on the side of the first gap 2011, and will not be described in detail here.

[0074] Continue reading Figure 1and Figure 2 The distance between the second end of the first radiating edge 2014-1 and the second end of the second radiating edge 2014-2 is less than the length of the side of the first gap 2011 or the second gap 2012.

[0075] When the radiating slot 2014 is located on the side of the first slot 2011 away from the third slot 2013, the shape formed by the combination of the radiating slot 2014 and the first slot 2011 can be a combination structure of virtual rectangle and virtual triangle. This setting increases the number of different spacings in the first slot 2011, further effectively expanding the bandwidth of the directional antenna and improving the gain of the directional antenna.

[0076] Of course, the distance between the second end of the first radiating edge 2014-1 and the second end of the second radiating edge 2014-2 can be equal to the side length of the first gap 2011, which is equivalent to one side of the first gap 2011 forming one side of a virtual triangle.

[0077] Continue reading Figure 2 Based on the above embodiments, the difference is that a third radial edge 2014-3 is connected between the first radial edge 2014-1 and the second radial edge 2014-2. The third radial edge 2014-3 is parallel to the side of the first gap 2011 or the second gap 2012. The first radial edge 2014-1, the second radial edge 2014-2 and the third radial edge 2014-3 enclose a virtual trapezoidal region.

[0078] In the directional antenna provided by the present invention, the first slot 2011 and the second slot 2012 are arranged in parallel, and the third slot 2013 is vertically connected between the first slot 2011 and the second slot 2012, so that the first slot 2011, the second slot 2012 and the third slot 2013 form a region with a shape similar to "I". The radiation slot 2014 can be arranged on one side of the "I" shaped slot region, or the radiation slot 2014 can be symmetrically arranged on both sides of the "I" shaped slot region.

[0079] When the radiating slot 2014 is positioned on one side of the "I"-shaped slot region, that is, when the radiating slot 2014 is located on the side of the first slot 2011 away from the third slot 2013, the shape of the radiating element 201 is similar to the shape formed by the combination of the "I"-shaped slot region and the virtual trapezoidal region. This arrangement allows for more different spacings to be formed in the first slot 2011, further effectively expanding the bandwidth of the directional antenna and improving its gain.

[0080] When the shape of the radiation groove 2014 is a virtual trapezoidal region, similar to the virtual triangular region of the radiation groove 2014 described above, the distance between the second end of the first radiation edge 2014-1 and the second end of the second radiation edge 2014-2 can be less than the length of the side of the first gap 2011 or the second gap 2012. The distance between the second end of the first radiation edge 2014-1 and the second end of the second radiation edge 2014-2 can also be equal to the length of the side of the first gap 2011 or the second gap 2012.

[0081] Continue reading Figure 1 and Figure 2 In order to further improve the gain of the directional antenna, multiple radiating elements 201 are arranged in an array along the length of the patch body 200. For example, two, three or four radiating elements 201 are arranged at equal intervals, and the spacing between two adjacent radiating elements 201 is 30mm to 40mm.

[0082] The following detailed explanation uses the example of four equally spaced radiating elements 201 arranged along the length of the patch body 200 as an example.

[0083] Figure 3 This is one of the front views of the dielectric substrate in the directional antenna provided in the embodiments of the present invention.

[0084] Continue reading Figure 1 and Figure 2 And see also Figure 3 The radiating unit 201 can be formed by etching on the dielectric substrate 100, or it can be attached to the dielectric substrate 100 by means of a patch having the radiating unit 201.

[0085] During the manufacturing process, four I-shaped grooves are first cut at equal intervals into a rectangular metal patch with a length l of 120mm to 160mm and a width w of 30mm to 50mm to form a radiating unit 201. The shape and size of this metal patch, i.e., the patch body 200, are the same as those of the dielectric substrate 100. Then, the metal patch with the radiating unit 201 is attached to the first surface of the dielectric substrate 100.

[0086] The spacing x between the four "I"-shaped slots is 30mm to 40mm, meaning the spacing between two adjacent radiating elements 201 is 30mm to 40mm. This spacing ensures improved gain while avoiding unnecessary sidelobes. If the spacing x between the four "I"-shaped slots is greater than this range, the beamwidth will increase, but the gain will decrease. If the spacing x between the four "I"-shaped slots is less than this range, unnecessary sidelobes will be generated, forming sidelobe clutter.

[0087] Continue reading Figure 3The dimensions of the radiating element 201 are described in detail below. To clearly illustrate the corresponding dimensions of the radiating element 201, letters a to I are used to represent the dimensions of the radiating element 201. Here, a is the length of the first slit 2011, ranging from 20mm to 40mm; b is the length of the third slit 2013, ranging from 8mm to 16mm; c is the length of the second slit 2012, ranging from 8mm to 16mm; d is the distance between the second end of the first radiating edge 2014-1 and the second end of the second radiating edge 2014-2, ranging from 15mm to 25mm; e is the length of the third radiating edge 2014-3, ranging from 1mm to 6mm; f is the width of the first slit 2011, ranging from 3mm to 9mm; and g is the distance between the first slit 2011 and the second slit 2012, ranging from 1mm to 6mm. h is the width of the second gap 2012, and the value of h ranges from 3mm to 9mm. i is the width of the radiation groove 2014, and the value of i ranges from 3mm to 10mm. m is the distance between the first gap 2011 and the upper edge of the patch body 200, and the value of m ranges from 5mm to 12mm.

[0088] To simplify the design of the directional antenna, the lengths of the first slot 2011 and the second slot 2012 are equal, i.e., a = c. The values ​​of a and c affect the shift of the high-frequency harmonic frequency point to the low frequency. When the values ​​of a and c are increased, the high-frequency harmonic frequency point shifts to the low frequency, and the resonance amplitude decreases.

[0089] Furthermore, the values ​​of b, e, and i also affect the shift of high-frequency harmonic frequencies towards lower frequencies. Keeping the values ​​of a and c constant while increasing the values ​​of b, e, and i will cause the high-frequency harmonic frequencies to shift towards lower frequencies, resulting in a decrease in the resonance amplitude. The values ​​of b, d, and m will affect the magnitude and amplitude of the low-frequency resonant point.

[0090] In this embodiment of the invention, by adjusting the various dimensional parameters of the above-mentioned radiating element 201 and the thickness of the dielectric substrate 100, the resonance amplitude of both the 2.4GHz band (2.40GHz~2.48GHz) and the 5GHz band (5.0GHz~5.8GHz) is determined to be below -10dB, thereby meeting the high gain requirement of the directional antenna.

[0091] Figure 4 This is a rear view of the second embodiment of the directional antenna provided in this invention.

[0092] See Figure 4Based on the above embodiments, the microstrip feeder assembly 300 includes a plurality of microstrip feeder lines 301, the position of each microstrip feeder line 301 corresponding one-to-one with the position of each radiating unit 201. Adjacent microstrip feeder lines 301 are arranged opposite to each other, and adjacent microstrip feeder lines 301 are connected by branch transmission lines 302. Adjacent branch transmission lines 302 are connected by trunk transmission lines 303, and the trunk transmission lines 303 are provided with a feeder interface.

[0093] Additionally, an impedance matching stub 304 connects the branch transmission line 302 and the main transmission line 303. This allows for impedance matching and adjustment of the microstrip feed assembly 300.

[0094] That is, the microstrip feed assembly 300 serves as a microstrip feed source, fulfilling the function of matching a 50-ohm coaxial cable. The microstrip feed assembly 300 has multiple impedance matching stubs, i.e., multiple microstrip feed wires 301. In this embodiment of the invention, the number of microstrip feed wires 301 corresponds to the number of radiating units 201. When there are four radiating units 201 arranged in an array, the number of microstrip feed wires 301 is four. These four microstrip feed wires 301 serve as matching stubs, playing a role in impedance matching. At the end of the microstrip feed assembly 300, part of the energy is consumed in the microstrip feed wires 301 that serve as matching stubs, and the other part is coupled to the hollowed-out metal patch through the "I"-shaped slot area. The radiating units 201 on the metal patch, i.e., the patch body 200, radiate the signal outward.

[0095] Figure 5 This is a rear view of the dielectric substrate in the directional antenna provided in an embodiment of the present invention.

[0096] See Figure 5 Based on the above embodiments, the difference is that the reflector 400 is disposed on one side of the second surface of the dielectric substrate 100 and has a certain gap with the second surface of the dielectric substrate 100 so that the reflector 400 can reflect electromagnetic waves. That is, the reflector 400 is added below the dielectric substrate 100, and the dielectric substrate 100 is fixedly connected to the reflector 400 through the connection hole 101.

[0097] By adding a reflector 400 below the dielectric substrate 100, good unidirectional radiation characteristics can be achieved, thereby improving the gain of the directional antenna. The gain of the directional antenna is greater than 10 dBi in the operating frequency band, and the maximum gain can reach 12.92 dBi.

[0098] The reflector 400 can be made of metal or a PCB board.

[0099] Figure 6 yes Figure 1The frequency response diagram of the reflection parameters of the directional antenna shown is presented; from Figure 6 It is known that this directional antenna can resonate in both the 2.4GHz band (2.40GHz~2.48GHz) and the 5GHz band (5.0GHz~5.8GHz) to achieve dual-band switching. Furthermore, the directional antenna has operating frequency bands with reflection coefficients below -10dB in the ranges of 2.36~2.65GHz, 3.27~3.6GHz, and 4.88~6.27GHz, fully covering the two required operating frequency bands, the 2.4GHz band and the 5GHz band.

[0100] Figure 7 yes Figure 1 The far-field radiation pattern (5.2 GHz) of the directional antenna shown; Figure 8 yes Figure 1 The diagram shows the center gain-frequency response of the directional antenna from 5.0 GHz to 5.8 GHz (radiation direction: θ = 0°). ).

[0101] Depend on Figure 7 and Figure 8 It can be seen that the directional antenna has good unidirectional radiation characteristics in the 2.4GHz band, and the E-plane and H-plane radiation patterns of the antenna element when operating at 2.4GHz have good symmetry. Adding a metal reflector 400 below the directional antenna achieves good unidirectional radiation characteristics and improves the gain of the directional antenna. The gain of the directional antenna is greater than 10dBi in the operating frequency band, with a maximum gain of 12.92dBi, making it suitable for broadband wireless communication systems.

[0102] Figure 9 yes Figure 1 The far-field radiation pattern (2.44 GHz) of the directional antenna shown; Figure 10 yes Figure 1 The diagram shows the center gain-frequency response of the directional antenna from 2.40 GHz to 2.48 GHz (radiation direction: θ = 0°). ).

[0103] Depend on Figure 9 and Figure 10 It can be seen that the directional antenna has good unidirectional radiation characteristics in the 5GHz band, and the E-plane and H-plane radiation patterns of the antenna element when operating at 5GHz have good symmetry. Adding a metal reflector 400 below the directional antenna achieves good unidirectional radiation characteristics and improves the gain of the directional antenna. The gain of the directional antenna is greater than 10dBi in the operating frequency band, with a maximum gain of 10.30dBi, making it suitable for broadband wireless communication systems.

[0104] Figure 11This is a schematic diagram of the directional antenna structure before the improvement of the embodiment of the present invention; Figure 12 This is a comparison diagram of the reflection parameters and frequency characteristics of the directional antenna before the improvement of the embodiment of the present invention; Figure 13 This is a diagram showing the 2.44GHz gain effect of the directional antenna before the improvement in this embodiment of the invention; Figure 14 This is a graph showing the 5.2GHz gain effect of the directional antenna before the improvement in this embodiment of the invention.

[0105] Depend on Figures 10 to 14 It can be seen that the unmodified and unimproved "I"-shaped gap area cannot achieve the WIFI dual-band (2.4GHz & 5GHz) standing wave effect of the improved "I"-shaped gap area with radiating groove 2014, and its resonance depth is much lower than that of the "I"-shaped gap area with radiating groove 2014, and it cannot achieve the high gain of WIFI dual-band (2.4GHz & 5GHz).

[0106] Therefore, the directional antenna provided in this embodiment of the invention, by providing at least one radiating element 201 in the patch body 200, each radiating element 201 includes a first slot 2011 and a second slot 2012 arranged in parallel, a third slot 2013 connecting the first slot 2011 and the second slot 2012, and a radiating slot 2014 connected to one side of at least one of the first slot 2011 and the second slot 2012, the radiating slot 2014 being located on the side of the first slot 2011 or the second slot 2012 facing away from the third slot 2013. In this way, multiple spacings are formed in the first slot 2011 or the second slot 2012, and these multiple spacings correspond to multiple different frequency points, thereby effectively expanding the bandwidth of the directional antenna and improving its gain.

[0107] Moreover, the directional antenna provided by this invention can adapt to different transmission environments. For example, in urban areas where the 2.4GHz band is heavily interfered with, the 5GHz band can be selected to improve communication stability, while in suburban areas where there is less wireless interference, the 2.4GHz band can be used to ensure a longer transmission distance.

[0108] In the manufacturing process of the directional antenna provided in this embodiment of the invention, a metal patch is printed on the first surface (upper surface) of the dielectric substrate 100. The metal patch has a pre-cut structure, that is, four "I"-shaped slots are cut out at equal intervals on the metal patch to form a radiating element 201. A microstrip feed assembly 300 is printed on the second surface (lower surface) of the dielectric substrate 100 as a microstrip feed source. One end of the trunk transmission line 303 in the microstrip feed assembly 300 is connected to the outer core of the coaxial microstrip feed line 301 through a solder joint. The radiating element 201 is connected to the inner core of the coaxial microstrip feed line 301 through a solder joint.

[0109] The radiating element 201 mainly consists of an "I"-shaped slot region formed by a first slot 2011 and a second slot 2012 symmetrically arranged with the center of the third slot 2013 as the center of symmetry. One side of the "I"-shaped slot region is a radiating slot 2014 in the shape of a virtual trapezoid. A metal reflector 400 is attached below the antenna to obtain unidirectional radiation and improve the antenna gain.

[0110] The directional antenna provided in this invention has high gain and can be effectively applied to directional wireless transmission products, such as bridges, base stations, radar, and GPS devices. It is adaptable to different transmission environments; in urban areas where 2.4GHz band interference is severe, the 5GHz band can be used to improve communication stability, while in suburban areas with less wireless interference, the 2.4GHz band can be used to achieve longer transmission distances. Compared to traditional antennas, this invention achieves lower antenna costs by using a simple PCB manufacturing process and the less expensive FR-4 material, while maintaining high gain in both frequency bands.

[0111] The present invention also provides an electronic device, which includes a device body and a directional antenna as described above. The device body can be equipped with the directional antenna to realize wireless communication. The directional antenna can be used in Internet of Things, smart hardware products and products that need to transmit data via the Internet.

[0112] It should be noted that the technical solutions in the various embodiments of the present invention can be combined with each other, but the basis for such combination is that they can be implemented by those skilled in the art; when the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist, that is, it is not within the protection scope of the present invention.

[0113] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A directional antenna, characterized in that, The array includes a reflector, a dielectric substrate disposed on the reflector, and at least one slot antenna array disposed on the dielectric substrate, wherein: The dielectric substrate has a first surface and a second surface disposed opposite to each other; The slot antenna array is disposed on the first surface of the dielectric substrate. The slot antenna array includes a plurality of radiating elements arranged in an array. Each radiating element includes a first slot and a second slot arranged in parallel with each other. A third slot connects the first slot and the second slot. A radiation groove is connected to one side of the first gap and / or the second gap, and the radiation groove is located on the side of the first gap or the second gap away from the third gap; the radiation groove has a first radiation edge and a second radiation edge arranged opposite to each other; The first radiating edge and the second radiating edge are arranged at an angle to each other, the first ends of the first radiating edge and the second radiating edge are connected to each other, and the second ends of the first radiating edge and the second radiating edge are both connected to the side of the first gap or the second gap.

2. The directional antenna according to claim 1, characterized in that, The distance between the second end of the first radiating edge and the second end of the second radiating edge is less than the length of the side of the first gap or the second gap.

3. The directional antenna according to claim 1, characterized in that, A third radiating edge is connected between the first end of the first radiating edge and the first end of the second radiating edge; The third radiating edge is parallel to the side of the first gap or the second gap, and the first radiating edge, the second radiating edge and the third radiating edge enclose a virtual trapezoidal region.

4. The directional antenna according to claim 1, characterized in that, It also includes a microstrip feed assembly for feeding the directional antenna, the microstrip feed assembly including a plurality of microstrip feed lines, the position of each microstrip feed line corresponding one-to-one with the position of each of the radiating elements; The two adjacent microstrip feed lines are arranged opposite each other, and the two adjacent microstrip feed lines are connected by a branch transmission line. The two adjacent branch transmission lines are connected by a trunk transmission line, and the trunk transmission line is provided with a power supply interface.

5. The directional antenna according to claim 4, characterized in that, The branch transmission line and the trunk transmission line are connected by an impedance matching stub.

6. The directional antenna according to any one of claims 1 to 5, characterized in that, The reflector is located on one side of the second surface of the dielectric substrate and has a gap between it and the second surface of the dielectric substrate.

7. The directional antenna according to any one of claims 1 to 5, characterized in that, Multiple radiating units arranged in an array are disposed on the patch body, and the spacing between two adjacent radiating units is 30 mm to 40 mm; The length of the dielectric substrate is 120 mm to 160 mm, and the width of the dielectric substrate is 30 mm to 50 mm.

8. An electronic device, characterized in that, It includes a device body and a directional antenna as described in any one of claims 1 to 7, wherein the directional antenna is applied to the device body.

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