PCB antenna and intelligent street lamp system

Abstract

The utility model provides a PCB antenna and an intelligent street lamp system, and relates to the technical field of antennas, and the PCB antenna comprises a coaxial cable, a rigid PCB, and a first radiation unit, a second radiation unit and a first reference ground which are respectively arranged on the rigid PCB. The central conductor of the coaxial cable is electrically connected with the second radiation unit through the first radiation unit, and the external conductor of the coaxial cable is electrically connected with the first reference ground. The coaxial cable, the first radiation unit and the second radiation unit generate resonance in a first frequency band. The first reference ground is located in a gap between the first radiation unit and the second radiation unit, and the first reference ground is coupled with the first radiation unit and the second radiation unit to generate resonance in a second frequency band. According to the design, the overall size of the PCB antenna is reduced, the cost is reduced, the PCB antenna can adapt to a small-space installation environment, signal transmission and receiving in multiple frequency ranges can be supported at the same time, the bandwidth of the PCB antenna is improved, and the requirements in multiple communication scenes are met.

Description

Technical Field

[0001] This application relates to the field of antenna technology, and more specifically, to a PCB antenna and a smart street light system. Background Technology

[0002] As a key infrastructure in smart city construction, smart streetlights integrate multiple functions such as lighting, monitoring, and communication, achieving multi-pole integration, optimizing the use of public spaces, improving lighting management efficiency, and promoting energy conservation and emission reduction, bringing significant social and economic benefits. With the rapid development of smart cities, the smart streetlight industry has risen rapidly, and the importance of antenna systems has become increasingly prominent. By integrating PCB antennas, smart streetlights can achieve functions such as precise positioning, centralized management, real-time status query, and strategy adjustment.

[0003] However, most common PCB antennas currently use the Cable+FPC (Flexible Printed Circuit Board) form, which usually requires a large area and a certain clearance area to achieve their performance. They generally suffer from problems such as large size, large space occupation, and high cost. Smart streetlights have less space and often cannot provide an ideal installation environment, making it difficult to balance the performance, cost, and size of the antenna. Utility Model Content

[0004] The purpose of this application is to provide a PCB antenna and a smart street light system to address the shortcomings of the prior art.

[0005] To achieve the above objectives, the technical solutions adopted in the embodiments of this application are as follows:

[0006] In one aspect of this application, a PCB antenna is provided, including a coaxial cable, a rigid PCB board, and a first radiating element, a second radiating element, and a first reference ground respectively disposed on the rigid PCB board, wherein the first reference ground is located in the gap between the first radiating element and the second radiating element.

[0007] The center conductor of the coaxial cable is electrically connected to the second radiating unit via the first radiating unit, and the outer conductor of the coaxial cable is electrically connected to the first reference ground.

[0008] The coaxial cable, the first radiating element, and the second radiating element resonate in the first frequency band, and the first reference ground is coupled to the first radiating element and the second radiating element to resonate in the second frequency band.

[0009] Optionally, the coaxial cable, the first radiating unit, and the second radiating unit together form a first resonant path for generating resonance in the first frequency band. The length of the first resonant path is equal to one-quarter wavelength of the first frequency band, and the length of the first reference ground is less than one-quarter wavelength of the first frequency band.

[0010] Optionally, the first radiating element, the first reference ground, and the second radiating element are arranged in parallel and spaced apart along the first direction on a rigid PCB board.

[0011] Optionally, the length of the second radiating element along the second direction is greater than the length of the first radiating element along the second direction, and the second direction is perpendicular to the first direction.

[0012] Optionally, the spacing between the first reference ground and the first radiating element is equal to the width of the first reference ground along the first direction, and / or the spacing between the first reference ground and the second radiating element is equal to the width of the first reference ground along the first direction.

[0013] Optionally, the PCB antenna also includes a third radiating element disposed on a rigid PCB board. The first radiating element is electrically connected to the second radiating element through the third radiating element, and the first radiating element and the third radiating element resonate in the third frequency band.

[0014] Optionally, the first radiating element and the third radiating element together form a third resonant path for generating resonance in the third frequency band, the length of which is equal to one-quarter wavelength of the third frequency band.

[0015] Optionally, the third radiating unit has a tip protruding in a direction away from the second radiating unit, and the distance between the tip and the coaxial cable is greater than or equal to the distance between the end of the first radiating unit closest to the third radiating unit and the coaxial cable.

[0016] Optionally, the PCB antenna also includes a second reference ground disposed on a rigid PCB board, and the outer conductor of the coaxial cable is electrically connected to the first reference ground via the second reference ground;

[0017] The second reference ground, the first radiating element, and the first reference ground are arranged in parallel and spaced apart along the first direction on a rigid PCB board.

[0018] In another aspect of this application, a smart street light system is provided, including a street light and a PCB antenna of any of the above types, wherein the coaxial cable of the PCB antenna is electrically connected to the main board of the street light.

[0019] The beneficial effects of this application include:

[0020] This application provides a PCB antenna and a smart street light system. The PCB antenna includes a coaxial cable, a rigid PCB board, and a first radiating element, a second radiating element, and a first reference ground, respectively disposed on the rigid PCB board. The center conductor of the coaxial cable is electrically connected to the first and second radiating elements via the first radiating element, and the outer conductor of the coaxial cable is electrically connected to the first reference ground. The coaxial cable, the first radiating element, and the second radiating element resonate in a first frequency band. The first reference ground is located within the gap between the first and second radiating elements and is coupled to the first and second radiating elements to resonate in the second frequency band. By using a rigid PCB board with a high dielectric constant and through a reasonable circuit layout, the coaxial cable not only acts as a conductor for signal transmission but also participates in the resonance process, thereby effectively reducing the overall size of the PCB antenna, lowering the cost, and enabling the PCB antenna to adapt to small-space installation environments. Furthermore, through this multi-band resonant design, the PCB antenna can simultaneously support signal transmission and reception in multiple frequency ranges, increasing the bandwidth of the PCB antenna, reducing the voltage standing wave ratio to below 3.0, and increasing the radiation efficiency to over 30%, meeting the needs of smart street light systems in various communication scenarios. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is one of the structural schematic diagrams of a PCB antenna provided in the embodiments of this application;

[0023] Figure 2 This is a second schematic diagram of the structure of a PCB antenna provided in an embodiment of this application;

[0024] Figure 3 A voltage standing wave ratio (VSWR) curve of a PCB antenna provided in an embodiment of this application;

[0025] Figure 4 The radiation efficiency curve of a PCB antenna provided in this application embodiment.

[0026] Icons: 1-Coaxial cable; 2-Rigid PCB board; 31-First radiating unit; 32-Second radiating unit; 33-Third radiating unit; 41-First reference ground; 42-Second reference ground; a-First direction; b-Second direction. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. It should be noted that, unless otherwise specified, the various features in the embodiments of this application can be combined with each other, and the combined embodiments are still within the protection scope of this application.

[0029] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0030] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and 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 should not be construed as a limitation on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0031] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0032] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0033] One aspect of this application provides a PCB antenna suitable for devices with complex structures and limited space, such as smart street light systems. Figure 1 As shown, the PCB antenna includes a coaxial cable 1, a rigid PCB board 2, and a first radiating element 31, a second radiating element 32, and a first reference ground 41 respectively disposed on the rigid PCB board 2. One end of the center conductor of the coaxial cable 1 is electrically connected to the second radiating element 32 through the first radiating element 31, and the other end is electrically connected to the main board of the smart street light system. One end of the outer conductor of the coaxial cable 1 is connected to the first reference ground 41, and the other end is connected to the reference ground on the main board. This connection method can ensure impedance consistency, thereby significantly improving signal transmission efficiency.

[0034] Specifically, by employing a rigid PCB board 2 with a high dielectric constant and a reasonable circuit layout, the coaxial cable 1 can not only perform signal transmission but also participate in the resonance process, resonating with the first radiating element 31 and the second radiating element 32 in the first frequency band. This effectively reduces the overall size of the PCB antenna, significantly lowering manufacturing and installation costs. It also allows the PCB antenna to adapt to small-space installation environments, avoiding the space-consuming problem of existing technologies that require larger radiating elements and reference grounds to achieve multi-band signal transmission and reception. Furthermore, the rigid PCB board 2 offers superior structural stability, facilitating installation and fixation, and improving installation consistency and reliability.

[0035] The rigid PCB board 2 preferably uses the common FR-4 material. FR-4 typically has a dielectric constant between 4.0 and 4.5, which contributes to the stability of antenna resonance and signal transmission performance. It also has strong bending resistance, maintaining the stability of the antenna structure during installation and use. Furthermore, it is low in cost and easy to mass-produce, making it suitable for cost-sensitive applications such as smart streetlights. In addition to FR-4, the rigid PCB board 2 can also be made of other rigid materials with high dielectric constant and low loss characteristics, such as ceramic substrates, PTFE substrates, and metal composite substrates, depending on the actual application requirements.

[0036] Furthermore, the first reference ground 41 is located between the first radiating element 31 and the second radiating element 32, and can resonate in the second frequency band through electromagnetic coupling with both. This arrangement can also generate certain parasitic currents. These parasitic currents form new radiation paths, which can increase the bandwidth of the second frequency band, expand the radiation range of the PCB antenna, optimize the radiation pattern, and improve the overall radiation efficiency of the antenna system.

[0037] Overall, this PCB antenna design features small size, low cost, and excellent performance. Its multi-band resonant design significantly improves the bandwidth of the PCB antenna, reduces the voltage standing wave ratio (VSWR) to below 3.0, and increases radiation efficiency to over 30%, thus achieving a balance between performance and cost. In smart street light systems, this PCB antenna can meet various functional requirements such as data transmission, status monitoring, and real-time control, ensuring the stability and efficiency of multi-band communication in smart street light systems.

[0038] Optionally, in the prior art, the coaxial cable 1 typically serves only as a conductor for signal transmission and does not directly participate in the antenna's resonance process. To achieve multi-band signal transmission and reception, traditional antenna designs require large radiating elements and a reference ground. Therefore, in this embodiment, the length of the first reference ground 41 is set to be less than a quarter wavelength of the first frequency band, allowing the coaxial cable 1 to participate in the resonance process.

[0039] Specifically, the coaxial cable 1, the first radiating element 31, and the second radiating element 32 are organically combined to form a first resonant path. The total length of the first resonant path is precisely designed to be one-quarter wavelength of the first frequency band. By introducing the coaxial cable 1 into the resonant path, the antenna can generate electromagnetic wave resonance using the conductor portion of the coaxial cable 1, thereby reducing the design size of the first radiating element 31 and the second radiating element 32. To ensure the stability of the resonant path, the coaxial cable 1 must be kept straight to avoid bending that would degrade the resonant performance.

[0040] It should be noted that, since the lengths of coaxial cable 1, the first radiating element 31, and the second radiating element 32 are interrelated, the arrangement length of any one component will affect the other components. Therefore, it is necessary to adjust the lengths of all three or two simultaneously to ensure that the total length of the first resonant path is always equal to one-quarter wavelength of the first frequency band. By adjusting the physical dimensions and relative positions of coaxial cable 1, the first radiating element 31, and the second radiating element 32, precise control of antenna performance can be achieved, thereby adapting to the needs of different equipment environments.

[0041] Optionally, such as Figure 1As shown, the PCB antenna also includes a third radiating element 33 disposed on the rigid PCB board 2, and the first radiating element 31 is electrically connected to the second radiating element 32 via the third radiating element 33. At this time, the coaxial cable 1, the first radiating element 31, the third radiating element 33, and the second radiating element 32 can resonate in the first frequency band, while the first radiating element 31 and the third radiating element 33 can resonate in the third frequency band. The ingenious combination of different radiating elements can achieve efficient signal transmission and reception in multiple frequency bands, while significantly improving the antenna's bandwidth performance to meet various communication needs. The first frequency band has a longer wavelength and a lower corresponding frequency, while the third frequency band has a shorter wavelength and a higher corresponding frequency. For example, the first frequency band is 700-960MHz, and the third frequency band is 1710-1880MHz. The two frequency bands do not overlap to ensure that signals in different frequency bands do not interfere with each other. Furthermore, by allocating different communication tasks to different frequency bands, it can be ensured that each frequency band is fully utilized, thereby improving overall communication efficiency.

[0042] Optionally, the coaxial cable 1, the first radiating element 31, the third radiating element 33, and the second radiating element 32 together form a first resonant path for generating resonance in the first frequency band. The length of the first resonant path is designed to match a quarter wavelength of the first frequency band to ensure that the antenna can achieve efficient resonance in the first frequency band and achieve optimal signal transmission and reception performance. The first radiating element 31 and the third radiating element 33 together form a third resonant path for generating resonance in the third frequency band. The length of the third resonant path is equal to a quarter wavelength of the third frequency band, thus ensuring that the antenna also has excellent resonance performance in the third frequency band. This multi-path segmented resonance method can effectively reduce the physical size of the antenna, making it more suitable for complex devices with limited space. At the same time, the clear division of labor between paths can reduce interference between frequency bands, improve the antenna's signal transmission efficiency and bandwidth utilization, and ultimately achieve the design goals of high performance, multi-functionality, and miniaturization.

[0043] Optionally, such as Figure 1 As shown, the third radiating unit 33 has a protruding tip that protrudes away from the second radiating unit 32. This protruding design helps to form a larger length in a limited space. The distance between the tip and the coaxial cable 1 is greater than or equal to the distance between the end of the first radiating unit 31 near the third radiating unit 33 and the coaxial cable 1, which can effectively prevent electromagnetic interference problems caused by excessive proximity between components.

[0044] Specifically, the spacing between each radiating element in the antenna structure and the coaxial cable 1 directly affects electromagnetic coupling and signal transmission quality. If the spacing between the tip of the third radiating element 33 and the coaxial cable 1 is too small, it may lead to excessive electromagnetic coupling or parasitic interference, thereby affecting the antenna's resonant performance and signal transmission efficiency. Therefore, by designing the spacing between the tip of the third radiating element 33 and the coaxial cable 1 to be greater than or equal to the spacing between one end of the first radiating element 31 and the coaxial cable 1, unnecessary electromagnetic interference can be effectively suppressed, ensuring stable and efficient signal transmission between each radiating element and the coaxial cable 1. Furthermore, this spacing design can optimize the electromagnetic field distribution, ensuring a moderate electromagnetic energy density at the tip of the third radiating element 33, and avoiding energy loss or signal distortion caused by excessive coupling.

[0045] It should be noted that the distance between the tip of the third radiating unit 33 and the coaxial cable 1 refers to the perpendicular distance between the tip of the third radiating unit 33 and the coaxial cable 1. That is, the length of the perpendicular line drawn from the tip of the third radiating unit 33 to the coaxial cable 1 is the distance between the tip of the third radiating unit 33 and the coaxial cable 1. Similarly, the distance between the end of the first radiating unit 31 closest to the third radiating unit 33 and the coaxial cable 1 refers to the perpendicular distance between the end of the first radiating unit 31 closest to the coaxial cable 1 and the coaxial cable 1. That is, the length of the perpendicular line drawn from the end of the first radiating unit 31 closest to the coaxial cable 1 is the distance between the end of the first radiating unit 31 closest to the third radiating unit 33 and the coaxial cable 1.

[0046] Optionally, such as Figure 1 As shown, the first radiating unit 31, the first reference ground 41 and the second radiating unit 32 are arranged in parallel and spaced apart along the first direction a on the rigid PCB board 2, thereby effectively utilizing space resources and enhancing the coupling effect of the resonant path.

[0047] Specifically, the third radiating unit 33 and the first radiating unit 31 are connected sequentially along the second direction b. The second direction b is perpendicular to the first direction a, and this perpendicular connection expands the simple linear structure into a multi-dimensional combined layout. The third radiating unit 33 and the second radiating unit 32 are connected by a connecting conductor, so that the multiple radiating units as a whole form a U-shaped groove. Among them, the first radiating unit 31 and the third radiating unit 33 serve as one sidewall of the U-shaped groove, the second radiating unit 32 serves as the other sidewall of the U-shaped groove, and the connecting conductor forms the bottom wall of the U-shaped groove. The U-shaped groove design is not only compact, but also has the advantage of enhanced coupling effect, making the overall structure more suitable for the needs of miniaturized devices.

[0048] The first reference ground 41 is designed between the two sidewalls of the U-shaped slot, making full use of the internal space of the U-shaped slot to ensure that the first reference ground 41 can participate efficiently in the resonance process. Through this compact layout, the first reference ground 41 can form stronger electromagnetic coupling and parasitic radiation with the first radiating element 31 and the second radiating element 32, which can further improve the transmission and reception efficiency of the second frequency band signal. Furthermore, the U-shaped slot design can provide a uniform electromagnetic field distribution, laying the foundation for the antenna's stable performance. For example, the second frequency band is 1880-2170MHz, which does not overlap with either the first or third frequency bands.

[0049] Optionally, such as Figure 1 As shown, the first radiating element 31, the second radiating element 32, and the first reference ground 41 are all designed as a linear structure extending along the second direction b. The linear structure has a continuous linear layout, which makes it easier to achieve resonance compared to a zigzag structure, ensuring efficient signal transmission and reception. Furthermore, the length of the second radiating element 32 along the second direction b is greater than the lengths of the first radiating element 31 and the first reference ground 41 along the second direction b. This length difference design enables multi-band signal transmission and reception, improving the antenna's bandwidth and operating efficiency.

[0050] To better accommodate the aforementioned linear layout, the shape of the rigid PCB board 2 has been adaptively optimized and can be designed as a rectangular structure with an extension extending along the second direction b. The rectangular structure design should fully consider the length, position, and spacing relationship between each radiating element and the reference ground, thereby achieving compact and efficient space utilization. Specifically, the length of the rectangular structure body along the second direction b is equal to or slightly greater than the sum of the lengths of the first radiating element 31, the third radiating element 33, and the first reference ground 41 along the second direction b, minus the overlap length between the first reference ground 41 and the first radiating element 31 and the third radiating element 33. This design optimizes the space of the rigid PCB board 2 and ensures the effective distribution of radiating elements and the reference ground, facilitating a rational structural layout.

[0051] Meanwhile, the width of the rectangular structure body along the first direction a is designed to be the sum of the widths of each radiating element (first radiating element 31, second radiating element 32, and third radiating element 33) along the first direction a, plus the spacing between the first radiating element 31 and the second radiating element 32. This width design not only ensures the independence between each radiating element and avoids unnecessary interference, but also ensures the stability and transmission efficiency of the overall antenna structure. Furthermore, the extension on the rectangular structure can further optimize space utilization; its length is designed to be the length of the second radiating element 32 along the second direction b minus the length of the rectangular structure body along the second direction b. This structural form ensures the extension length of the second radiating element 32 in the second direction b, thereby meeting the resonance requirements of the second frequency band.

[0052] In traditional technologies, to achieve signal transmission in the first frequency band (700-960MHz), the second frequency band (1880-2170MHz), and the third frequency band (1710-1880MHz), flexible printed circuit boards (FPCs) are typically used as antenna substrates. Furthermore, since the coaxial cable 1 does not participate in resonance, approximately 1100mm is required. 2 Only a certain area is needed to guarantee signal transmission across the three frequency bands mentioned above. This design occupies a large installation space, making it unsuitable for deployment in space-constrained devices and limiting the flexibility of application scenarios.

[0053] For example, such as Figure 2 As shown, in this embodiment, a coaxial cable 1 with an impedance of 50 ohms and a length of 42.44 mm is used; FR-4 material is selected as the substrate of the rigid PCB board 2, with a dielectric constant of 4.4, a thickness of 0.8 mm, a width of 16.48 mm along the first direction a, and a length of 44.3 mm along the second direction b (including the length of the rectangular structure body and the length of the extension). Through the above design, as... Figure 3 and Figure 4 As shown, the antenna can cover the first frequency band (700-960MHz), the second frequency band (1880-2170MHz), and the third frequency band (1710-1880MHz), meeting the needs of multi-band signal transmission and reception. The voltage standing wave ratio (VSWR) can be reduced to below 3.0, exhibiting excellent impedance matching performance, effectively reducing signal reflection and improving transmission efficiency. The radiation efficiency reaches over 30%, ensuring effective signal radiation across multiple frequency bands and enhancing the system's communication coverage and stability. Furthermore, the area of ​​the rigid PCB board 2 is only approximately 400mm². 2 With a size reduction of over 60%, it can greatly save installation space and is suitable for size-constrained equipment environments, such as streetlights and IoT terminals.

[0054] Optionally, the spacing between the first reference ground 41 and the first radiating element 31 is equal to the width of the first reference ground 41 along the first direction a, and / or, the spacing between the first reference ground 41 and the second radiating element 32 is equal to the width of the first reference ground 41 along the first direction a. This structural layout, by precisely controlling the spacing between the radiating element and the reference ground, can optimize the coupling effect between the radiating element and the reference ground, and improve the overall resonant performance.

[0055] Specifically, the spacing between the radiating element and the reference ground plays a crucial role in the antenna's coupling effect. An appropriate spacing helps strengthen the electromagnetic coupling between the radiating element and the reference ground, thus affecting the antenna's resonance performance in the second frequency band. Preferably, the spacing between the first reference ground 41 and the first radiating element 31 is equal to the width of the first reference ground 41 itself, and the spacing between the first reference ground 41 and the second radiating element 32 is set to be equal to the width of the first reference ground 41 along the first direction a, further enhancing the electromagnetic coupling effect in the second frequency band and ensuring resonance performance. It should be understood that the width of the first reference ground 41 along the first direction a determines the required spacing between the first radiating element 31 and the second radiating element 32. This spacing design not only meets the resonance requirements in the second frequency band but also reduces signal interference and transmission loss in the antenna structure.

[0056] Optionally, such as Figure 1 As shown, the PCB antenna also includes a second reference ground 42 disposed on the rigid PCB board 2. The outer conductor of the coaxial cable 1 is electrically connected to the second reference ground 42. The second reference ground 42 is electrically connected to the first reference ground 41 through a connecting conductor, forming a complete circuit path. Specifically, the second reference ground 42, the connecting conductor, and the first reference ground 41 are combined to form a U-shaped groove, wherein the second reference ground 42 and the first reference ground 41 serve as the two sidewalls of the U-shaped groove, and the connecting conductor serves as the bottom wall of the U-shaped groove.

[0057] This U-shaped groove is opposite to and interlocked with the U-shaped groove formed by the radiating units (including the first radiating unit 31 and the second radiating unit 32). That is, the second reference ground 42, the first radiating unit 31, the first reference ground 41, and the second radiating unit 32 together present a structural layout that is parallel and spaced apart along the first direction a. This ingenious spatial layout design achieves high integration, effectively utilizing the limited space of the PCB board, thereby improving structural compactness and the rationality of the overall design. At this time, the first radiating unit 31 is arranged inside the U-shaped groove formed by the reference grounds (first reference ground 41 and second reference ground 42), while the first reference ground 41 is located inside the U-shaped groove formed by the radiating units (first radiating unit 31 and second radiating unit 32), coupling with the radiating units to generate resonance in the second frequency band. The second reference ground 42, the connecting conductor, and the first reference ground 41 together form a second resonant path for generating resonance in the second frequency band. The length of the second resonant path is equal to one-quarter wavelength of the second frequency band.

[0058] Another aspect of this application provides a smart street light system, including a street light and any of the aforementioned PCB antennas. The PCB antenna is threaded or snapped onto the side wall of the street light, which can reduce installation costs and facilitate integration. The coaxial cable 1 of the PCB antenna is electrically connected to the main board of the street light. Specifically, one end of the center conductor of the coaxial cable 1 is electrically connected to the second radiating unit 32 through the first radiating unit 31, and the other end is electrically connected to the main board of the street light. One end of the outer conductor of the coaxial cable 1 is connected to the first reference ground 41, and the other end is connected to the reference ground on the main board of the street light. Since the smart street light system uses the aforementioned PCB antenna, it also has the same beneficial effects as the PCB antenna, which will not be elaborated further here.

[0059] It should be noted that since coaxial cable 1 participates in resonance in the antenna system, its placement needs to avoid metal devices or other structural components that may interfere with the propagation of electromagnetic waves. Metal materials may cause electromagnetic wave reflection or shielding, interfering with signal transmission and even affecting the antenna's resonance state. Therefore, in the antenna design of the smart street light system, to ensure that coaxial cable 1 can effectively participate in resonance and maintain optimal performance, and to minimize interference, the connection point between coaxial cable 1 and the rigid PCB board 2 should be located at the edge of the rigid PCB board 2, and the connection point between coaxial cable 1 and the street light main board should be designed at the edge of the main board.

[0060] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A PCB antenna, characterized in that, It includes a coaxial cable (1), a rigid PCB board (2), and a first radiating unit (31), a second radiating unit (32), and a first reference ground (41) respectively disposed on the rigid PCB board (2), wherein the first reference ground (41) is located in the gap between the first radiating unit (31) and the second radiating unit (32); The center conductor of the coaxial cable (1) is electrically connected to the second radiation unit (32) via the first radiation unit (31), and the outer conductor of the coaxial cable (1) is electrically connected to the first reference ground (41). The coaxial cable (1), the first radiating unit (31) and the second radiating unit (32) resonate in the first frequency band, and the first reference ground (41) is coupled to the first radiating unit (31) and the second radiating unit (32) to resonate in the second frequency band.

2. The PCB antenna according to claim 1, characterized in that, The coaxial cable (1), the first radiating unit (31), and the second radiating unit (32) together form a first resonant path for generating resonance in the first frequency band. The length of the first resonant path is equal to one-quarter wavelength of the first frequency band, and the length of the first reference ground (41) is less than one-quarter wavelength of the first frequency band.

3. The PCB antenna according to claim 1 or 2, characterized in that, The first radiating element (31), the first reference ground (41) and the second radiating element (32) are arranged in parallel and spaced apart along the first direction (a) on the rigid PCB board (2).

4. The PCB antenna according to claim 3, characterized in that, The length of the second radiating element (32) along the second direction (b) is greater than the length of the first radiating element (31) along the second direction (b), and the second direction (b) is perpendicular to the first direction (a).

5. The PCB antenna according to claim 3, characterized in that, The distance between the first reference ground (41) and the first radiation element (31) is equal to the width of the first reference ground (41) along the first direction (a), and / or the distance between the first reference ground (41) and the second radiation element (32) is equal to the width of the first reference ground (41) along the first direction (a).

6. The PCB antenna according to claim 1 or 2, characterized in that, The PCB antenna also includes a third radiating unit (33) disposed on the rigid PCB board (2). The first radiating unit (31) is electrically connected to the second radiating unit (32) through the third radiating unit (33). The first radiating unit (31) and the third radiating unit (33) resonate in the third frequency band.

7. The PCB antenna according to claim 6, characterized in that, The first radiating element (31) and the third radiating element (33) together form a third resonant path for generating resonance in the third frequency band, the length of which is equal to one-quarter wavelength of the third frequency band.

8. The PCB antenna according to claim 6, characterized in that, The third radiating unit (33) has a tip that protrudes in a direction away from the second radiating unit (32), and the distance between the tip and the coaxial cable (1) is greater than or equal to the distance between the end of the first radiating unit (31) near the third radiating unit (33) and the coaxial cable (1).

9. The PCB antenna according to claim 1 or 2, characterized in that, The PCB antenna also includes a second reference ground (42) disposed on the rigid PCB board (2), and the outer conductor of the coaxial cable (1) is electrically connected to the first reference ground (41) via the second reference ground (42); The second reference ground (42), the first radiation unit (31) and the first reference ground (41) are arranged in parallel and spaced apart along the first direction (a) on the rigid PCB board (2).

10. A smart street light system, characterized in that, The invention includes a street lamp and a PCB antenna as described in any one of claims 1 to 9, wherein the coaxial cable (1) of the PCB antenna is electrically connected to the mainboard of the street lamp.

Images