A wideband miniaturized terminal omnidirectional antenna

Abstract

This invention discloses a broadband miniaturized omnidirectional antenna for terminals, belonging to the field of communication antenna technology. It includes: an impedance matching feed circuit comprising an inductor and a capacitor fixedly mounted on a circuit board, one end of which is fixedly connected to a connector; a multi-stage capacitor module comprising multiple metal capacitor rings, one end of which is fixedly connected to the impedance matching feed circuit; and a radiating module comprising a first radiating element and a second radiating element arranged at relatively intervals, both fixedly connected to the multi-stage capacitor module. Both the first and second radiating elements have through-slots, and these slots have the same shape but opposite orientations. This invention provides a broadband miniaturized omnidirectional antenna for terminals that, while miniaturizing the antenna structure, ensures high bandwidth and high gain communication characteristics, effectively achieving antenna collapse and easy storage, and meeting the communication requirements of VHF / UHF band omnidirectional radiating antennas.

Description

Technical Field

[0001] This invention belongs to the field of communication antenna technology, specifically relating to a broadband miniaturized omnidirectional terminal antenna. Background Technology

[0002] With the rapid development of wireless communication systems and terrestrial VHF / UHF mid- and long-band communication, terrestrial communication systems are placing increasing demands and higher requirements on the performance of VHF / UHF antennas used for data communication based on actual usage requirements. In general terrestrial communication systems, such as vehicle-mounted and handheld communication, to ensure data communication capacity and reliable transmission and reception, and considering the complex communication environment, it is necessary to select VHF / UHF band horizontal omnidirectional radiating antennas with a wide operating frequency bandwidth and high gain. Furthermore, considering the limitations of the installation environment and the need for a good user experience, most existing VHF / UHF band omnidirectional radiating antennas adopt the dipole antenna form. Given the limited installation space and operating environment, most existing VHF / UHF band omnidirectional antenna products use biconical, symmetrical dipole, or monopole antenna designs to achieve omnidirectional radiation. However, these designs suffer from a series of drawbacks, including narrow operating bandwidth, large size, and being bulky and difficult to handle. While some methods for widening the operating bandwidth and achieving miniaturization can improve antenna performance to some extent, they do not fundamentally solve the problems. Furthermore, the following issues remain: First, while symmetrical dipole designs can achieve the resonant frequency, the electrical dimensions are only 0.5 times the maximum wavelength. 1. The narrow operating bandwidth cannot meet the requirements of miniaturization and wide bandwidth. 2. The antenna adopts a helical monopole design, which can reduce the size to a certain extent, but the small metal ground makes it difficult to operate at low frequencies and the operating bandwidth is narrow. 3. The antenna adopts a symmetrical biconical dipole design, which can broaden the bandwidth to a certain extent, but the lateral size is large and bulky. 4. Although the matching feed network technology built with independent resistors, inductors, capacitors and other components can achieve a certain wide bandwidth design, the feed network design is complex, the actual product standing wave matching and debugging is difficult, the feed network loss is large and prone to recurrence.

[0003] Based on the design methods of omnidirectional antennas, they can be classified into two categories: one type uses electric field rotation, and the other type uses spatial electric field superposition to achieve omnidirectional coverage of the antenna radiation field. The main difference between these two types lies in the different ways of achieving the same average power at every point in the far field of the antenna.

[0004] In practical engineering applications, the most commonly used omnidirectional antennas in the VHF / UHF bands are the two basic types: dipole antennas and monopole antennas. Considering mechanical structure, dipole and monopole antennas are simple in structure, easy to implement, and offer strong flexibility in form. For dipole antennas, to ensure high gain, their electrical length must be at least half the wavelength corresponding to the lowest operating frequency; while for monopole antennas, based on the image principle, to ensure high gain, their electrical length must be at least one-quarter the wavelength corresponding to the lowest operating frequency, and the metal ground must be infinitely large. In actual design, due to antenna size requirements, omnidirectional antennas often choose the monopole form and are designed for miniaturization.

[0005] Furthermore, simple monopole antennas cannot achieve a wide bandwidth. In the VHF / UHF bands, which belong to the medium and long wavebands, the vertical height of a monopole antenna is limited by the antenna structure size requirements due to the long wavelengths. This results in the antenna height being much smaller than the wavelength, leading to very low radiation resistance and relatively high loss resistance, thus resulting in very low radiation efficiency. Secondly, the antenna's input resistance is very small while its input reactance is very large, resulting in a high Q value and a sharp resonant curve, further limiting the antenna's operating bandwidth. Summary of the Invention

[0006] In response to one or more of the above-mentioned defects or improvement needs of the prior art, the present invention provides a broadband miniaturized terminal omnidirectional antenna that can ensure the antenna has high bandwidth and high gain communication characteristics as much as possible while achieving antenna structure miniaturization, thereby effectively realizing antenna collapse and easy storage, and meeting the communication requirements of VHF / UHF band omnidirectional radiating antennas.

[0007] To achieve the above objectives, the present invention provides a broadband miniaturized omnidirectional terminal antenna, comprising:

[0008] An impedance matching power supply circuit includes at least one inductor and at least one capacitor fixedly mounted on a circuit board, one end of which is fixedly connected to a connector for receiving and transmitting excitation power.

[0009] A multi-stage capacitor module; it includes at least one metal capacitor ring, one end of which is fixedly connected to the end of the impedance matching feed circuit away from the connector, for optimizing the impedance matching characteristics of the omnidirectional antenna and receiving and transmitting the excitation feed.

[0010] The radiation module includes a first radiating element and a second radiating element arranged at relatively intervals. Both are fixedly connected to the end of the multi-stage capacitor module away from the impedance matching power supply circuit. At the same time, the first radiating element and the second radiating element are provided with slots that penetrate the radiating element. The slots on the two are the same in shape and arranged in opposite directions to form the coupling structure of the radiation module, which is used to receive the excitation power supply to generate an excitation signal and complete horizontal omnidirectional radiation.

[0011] As a further preferred embodiment of the present invention, the slots are arranged in a triangular pattern on the first radiating oscillator and the second radiating oscillator.

[0012] As a further preferred embodiment of the present invention, an insulating interlayer is provided between the first radiating oscillator and the second radiating oscillator, which has the same shape as the first radiating oscillator and the second radiating oscillator, and is used for isolation between the first radiating oscillator and the second radiating oscillator.

[0013] As a further preferred embodiment of the present invention, the first radiating oscillator and the second radiating oscillator are made of thin steel tape measure material, and the insulating interlayer is made of thin polytetrafluoroethylene.

[0014] As a further preferred embodiment of the present invention, one end of the first radiating oscillator and the second radiating oscillator are fixed with a cap, and the other end is fixedly connected to the multi-stage capacitor module with a first fixing block and a second fixing block.

[0015] As a further preferred embodiment of the present invention, the cap is a T-shaped structure, which is used to improve the resonance matching of the omnidirectional antenna.

[0016] As a further preferred embodiment of the present invention, a protective cover is provided on the outside of the radiation module, the first fixing block and the second fixing block. The cover is made of heat-shrinkable material and is used to wrap and seal the radiation module, the first fixing block and the second fixing block.

[0017] As a further preferred embodiment of the present invention, the multi-stage capacitor module includes a plurality of metal capacitor rings, and the impedance characteristics of the multi-stage capacitor module are adjusted by adjusting the size of each of the metal capacitor rings.

[0018] As a further preferred embodiment of the present invention, the impedance matching feed circuit includes a plurality of inductors and a plurality of capacitors fixedly mounted on a circuit board, which adjusts the bandwidth of the omnidirectional antenna by adjusting the inductance and / or capacitance values ​​of each of the inductors and / or capacitors.

[0019] As a further preferred embodiment of the present invention, a protective sleeve is provided on the outside of the impedance matching power supply circuit and the multi-stage capacitor module to protect the impedance matching power supply circuit and the multi-stage capacitor module.

[0020] The aforementioned improved technical features can be combined with each other as long as they do not conflict with each other.

[0021] In summary, the beneficial effects of the above-described technical solutions conceived by this invention compared with the prior art include:

[0022] (1) The present invention provides a broadband miniaturized omnidirectional terminal antenna, which can effectively receive and adjust the excitation feed transmitted by the connector by setting an impedance matching feed circuit connected to the connector. At the same time, the excitation feed is received by a multi-stage capacitor module with at least one metal capacitor ring, and the excitation feed is further adjusted. Then, the adjusted excitation feed is stably transmitted to the radiating module. The radiating module has slots with the same shape and opposite arrangement on the first and second radiating elements, which not only improve the current flow path on the first and second radiating elements, but also form a symmetrical coupling structure, converting the feed circuit into a stable feed signal electromagnetic wave. Under the premise of miniaturizing the antenna structure, the antenna can be ensured to have high bandwidth and high gain communication characteristics as much as possible.

[0023] (2) The present invention provides a broadband miniaturized omnidirectional antenna for terminals. By using thin rigid tape measure material to fabricate two amplitude elements and thin polytetrafluoroethylene (PTFE) to fabricate an isolation interlayer, the omnidirectional antenna not only possesses high structural strength and signal transmission stability but also reduces its overall size, achieving the effects of easy collapse and storage. Simultaneously, by setting a T-shaped non-metallic cap, the first and second radiating elements can generate capacitance with the cap, thereby improving antenna resonance matching and suppressing antenna standing wave characteristics. Furthermore, by adjusting multiple metal structures of different widths and depths in the multi-stage capacitor module, the multi-stage capacitor module can generate a capacitive effect, forming a multi-stage capacitor loop to optimize the low-frequency impedance characteristics of the omnidirectional antenna. In addition, by setting and adjusting the capacitors and inductors in the impedance matching feed circuit, the impedance characteristics of the antenna can be easily improved over multiple frequency bands and a wide bandwidth, thereby achieving a broadband antenna design.

[0024] (3) The broadband miniaturized omnidirectional antenna of the present invention has a simple structure, high stability, and convenient use. It adopts a stable coupling structure by using a first radiating element and a second radiating element arranged opposite each other, and corresponding slots on the first radiating element and the second radiating element. This not only reduces the size of the omnidirectional antenna, but also ensures the stable transmission of the excitation signal electromagnetic wave. Furthermore, by adjusting the size of each metal capacitor ring in the multi-stage capacitor module, the impedance characteristics of the omnidirectional antenna are significantly optimized, thereby improving the impedance matching characteristics of the omnidirectional antenna. At the same time, by designing the corresponding capacitors and inductors in the impedance matching feed circuit, the impedance characteristics of the omnidirectional antenna can be improved in multiple frequency bands and a wide frequency range. This not only enables the bandwidth design of the antenna, but also ensures that the loss of the impedance matching feed circuit is small, thereby achieving the high gain design of the omnidirectional antenna. It has excellent economic benefits and promotional value. Attached Figure Description

[0025] Figure 1 This is a three-dimensional view of the internal structure of a broadband miniaturized terminal omnidirectional antenna according to the present invention;

[0026] Figure 2 This is a three-dimensional view of the internal structure of a broadband miniaturized terminal omnidirectional antenna from another perspective in this invention;

[0027] Figure 3 This is a three-dimensional view of the internal structure of a broadband miniaturized terminal omnidirectional antenna from another perspective in this invention.

[0028] Figure 4 This invention relates to a broadband miniaturized omnidirectional terminal antenna. Figure 3 Enlarged view of a portion of point A in the middle;

[0029] Figure 5 This is a three-dimensional view of the overall structure of a broadband miniaturized terminal omnidirectional antenna according to the present invention;

[0030] Figure 6 This is a schematic diagram of the first radiating element structure of a broadband miniaturized terminal omnidirectional antenna in this invention;

[0031] Figure 7 This is a schematic diagram of the cap structure of a broadband miniaturized terminal omnidirectional antenna in this invention;

[0032] Figure 8 This is a schematic diagram of a multi-stage capacitor module structure for a broadband miniaturized terminal omnidirectional antenna in this invention;

[0033] Figure 9 This is a front view of the impedance matching feed circuit of a broadband miniaturized terminal omnidirectional antenna in this invention;

[0034] Figure 10 This is a rear view of the impedance matching feed circuit of a broadband miniaturized terminal omnidirectional antenna in this invention.

[0035] Figure 11 This is a schematic diagram of the antenna standing wave of a broadband miniaturized omnidirectional antenna in this invention;

[0036] Figure 12 This is a schematic diagram of the gain direction of two different cross sections at the center frequency of a broadband miniaturized terminal omnidirectional antenna in this invention.

[0037] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically:

[0038] 1. Connector; 2. Impedance matching power supply circuit; 3. Banana plug; 4. Multi-stage capacitor module; 5. First fixing block; 6. Second fixing block; 7. First radiating oscillator; 8. Second radiating oscillator; 9. Insulating interlayer; 10. Cap; 11. Protective sleeve; 12. Protective cover; 13. Inductor L1; 14. Inductor L2; 15. Inductor L3; 16. Capacitor C1; 17. Capacitor C2; 18. Capacitor C3; 19. Capacitor C4. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0040] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention 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. Therefore, they should not be construed as limitations on this invention.

[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0042] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0043] In this invention, unless otherwise explicitly 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," "over," and "on top" of 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.

[0044] Example:

[0045] like Figures 1-12 As shown, the broadband miniaturized terminal omnidirectional antenna in the preferred embodiment of this application can ensure that the antenna has high bandwidth and high gain communication characteristics as much as possible while achieving antenna structure miniaturization, thereby effectively realizing antenna collapse and easy storage, and meeting the communication requirements of VHF / UHF band omnidirectional radiating antennas.

[0046] Specifically, such as Figures 1-5 As shown in the preferred embodiment of this application, the broadband miniaturized terminal omnidirectional antenna includes an impedance matching feed circuit 2, a multi-stage capacitor module 4, and a radiation module. The impedance matching feed circuit 2 includes a circuit board, and at least one inductor and at least one capacitor fixedly mounted on the circuit board. At the same time, one end of the circuit board is fixedly connected to a connector 1, and the excitation feed is received from an external system through the connector 1. Then, the at least one inductor and at least one capacitor set on the circuit board adjust the excitation feed and transmit the adjusted excitation feed, thereby ensuring that the omnidirectional antenna can start stably.

[0047] The multi-stage capacitor module 4 includes at least one metal capacitor ring for optimizing the impedance matching characteristics of the omnidirectional antenna. One end of the multi-stage capacitor module 4 is fixedly connected to the impedance matching feed circuit 2 for receiving and adjusting the excitation feed, and then transmitting the adjusted excitation feed to ensure the stability and accuracy of the signal transmitted by the omnidirectional antenna.

[0048] Meanwhile, the radiation module includes a first radiating oscillator 7 and a second radiating oscillator 8 arranged opposite to each other. Both the first radiating oscillator 7 and the second radiating oscillator 8 are fixedly connected to the multi-stage capacitor module 4 so that the excitation power after adjustment by the multi-stage capacitor module 4 can be stably transmitted to the first radiating oscillator 7 and the second radiating oscillator 8. Furthermore, both the first radiating oscillator 7 and the second radiating oscillator 8 are provided with slots that penetrate the oscillator. However, the slots provided on the two are the same in shape but arranged in opposite directions. That is, the slots on the two are symmetrical and mirror images. It can also be understood that the slots on the two are symmetrical along the center of the two. For example, the first radiating oscillator 7 is provided with a triangular slot and the second radiating oscillator 8 is provided with an inverted triangular slot. By setting the relatively arranged slot, it can change the current path on the first radiating element 7 and the second radiating element 8, which can not only effectively reduce the length of the first radiating element 7 and the second radiating element 8 to facilitate the flexible storage of the omnidirectional antenna, but also form a coupling structure distributed on the radiating module. After the radiating module receives the excitation feed adjusted by the multi-stage capacitor module 4, the excitation feed is converted into an excitation signal through the coupling structure formed by the first radiating element 7 and the second radiating element 8, and horizontal omnidirectional radiation is completed.

[0049] Furthermore, in a preferred embodiment of this application, the first radiating element 7 and the second radiating element 8 have identical shapes and structures, so that the two sides of the directional antenna respectively set on the first radiating element 7 and the second radiating element 8 can generate accurate and identical excitation signals, thereby ensuring the accuracy of information transmission by the omnidirectional antenna. Preferably, the first radiating element 7 is provided with a slot in an inverted triangular shape, and correspondingly, the slot provided on the second radiating element 8 is also in a triangular shape, thus forming a coupling structure on the radiating module.

[0050] Preferably, such as Figure 6 As shown, in a preferred embodiment of this application, by adjusting and optimizing the slit groove size parameters LL4, LL5, LL6, G1, G2, and W6, the miniaturization and resonant design of the first radiating oscillator 7 and the second radiating oscillator 8 are achieved, thereby ensuring that the first radiating oscillator 7 and the second radiating oscillator 8 form a symmetrical oscillator structure (i.e., a symmetrical coupling structure) to complete the horizontal omnidirectional radiation of the excitation signal.

[0051] More preferably, such as Figure 3and Figure 4 As shown in the preferred embodiment of this application, an insulating interlayer 9, similar in shape to the first radiating element 7 and the second radiating element 8, is provided between them. This serves two purposes: firstly, to isolate the first radiating element 7 and the second radiating element 8, preventing mutual interference after receiving excitation power; and secondly, to enhance the structural strength of the entire radiating module, facilitating the collapse operation of the omnidirectional antenna and improving its flexibility and ease of storage. Preferably, the insulating interlayer 9 is made of thin polytetrafluoroethylene (PTFE) to ensure the omnidirectional antenna has collapse strength while safely isolating the first radiating element 7 and the second radiating element 8. More preferably, the first radiating element 7 and the second radiating element 8 are made of thin rigid tape measure material, ensuring stable signal transmission of the omnidirectional antenna while minimizing its overall weight, further improving its flexibility and ease of storage.

[0052] More specifically, in a preferred embodiment of this application, a cap 10 is provided at the end of the first radiating element 7, the second radiating element 8, and the insulating interlayer 9 that is away from the multi-stage capacitor module 4. Preferably, the first radiating element 7, the second radiating element 8, and the insulating interlayer 9 are fixed to the cap 10 by potting glue. This not only fixes the first radiating element 7 and the second radiating element 8 at the end away from the multi-stage capacitor module 4, but also generates capacitance between the cap 10 and the first radiating element 7 and the second radiating element 8, thereby effectively improving the resonance matching of the directional antenna, thus producing the effect of suppressing the antenna standing wave characteristics and improving the signal transmission quality of the omnidirectional antenna.

[0053] Preferably, the cap 10 is made of a non-metallic material to form a T-shaped structure, and a metallized coating is provided on the outer surface of the cap 10. More preferably, such as... Figure 7 As shown, by adjusting and optimizing the structural parameters LL1, LL2, and LL3 of the cap 10, the capacitance between the cap 10, the first radiating element 7, and the second radiating element 8 is adjusted, thereby improving the resonance matching of the omnidirectional antenna.

[0054] Furthermore, in a preferred embodiment of this application, one end of the first radiating oscillator 7 and the second radiating oscillator 8 are fixedly mounted on the multi-stage capacitor module 4 by the first fixing block 5 and the second fixing block 6, so as to facilitate a stable connection between the multi-stage capacitor module 4 and the first radiating oscillator 7 and the second radiating oscillator 8 respectively.

[0055] Further preferably, in a preferred embodiment of this application, a protective sleeve 12 is provided on the outside of the first fixing block 5, the second fixing block 6, the first radiating vibrator 7, the second radiating vibrator 8, and the insulating interlayer 9, for wrapping and sealing the above-mentioned structural components, thereby achieving protection and sealing of the above-mentioned structure. Preferably, the protective sleeve 12 is made of heat-shrinkable material. In actual use, the heat-shrinkable sleeve is stably covered on the above-mentioned components under heat, completing the stable protection of each of the above-mentioned components.

[0056] More in detail, such as Figure 8 As shown in the preferred embodiment of this application, the multi-stage capacitor module 4 has an overall columnar structure, and multiple metal capacitor rings of different widths and depths are axially spaced on the outer wall of the columnar structure to form stable capacitor rings. Preferably, since the omnidirectional antenna is a monopole antenna, its metal ground is very small, resulting in a relatively large low-frequency impedance inductance of the antenna. By adjusting the dimensions W1, W2, W3, W4, W5, H1, H2, H3, and H4 of each metal capacitor ring in the multi-stage capacitor module 4, the impedance characteristics of the omnidirectional antenna can be further optimized, thereby effectively improving the impedance matching characteristics of the omnidirectional antenna.

[0057] Furthermore, in a preferred embodiment of this application, a banana plug 3 is provided between the multi-stage capacitor module 4 and the impedance matching feed circuit 2, and the two are fixedly connected through the banana plug 3. Preferably, the impedance matching feed circuit 2 is fixedly connected to the banana plug and the connector 1 by welding. More preferably, the multi-stage capacitor module 4 and the banana plug 3 are fixedly connected by plugging, thereby forming a complete antenna structure.

[0058] Further preferably, in a preferred embodiment of this application, a protective sleeve 11 is provided on the outside of the multi-stage capacitor module 4 and the impedance matching power supply circuit 2, preferably made of non-metallic material, to protect the multi-stage capacitor module 4 and the impedance matching power supply circuit 2.

[0059] More specifically, in a preferred embodiment of this application, the impedance matching feed circuit 2 includes multiple inductors and multiple capacitors fixedly mounted on a circuit board. The inductors are preferably made of enameled wire, and the capacitors are made of special cables. They are fixedly mounted on the circuit board by soldering to form a low-impedance impedance matching feed circuit 2. Preferably, by adjusting the inductance and capacitance values ​​of inductors L113, L214, L315 and / or capacitors C116, C217, C318, and C419 disposed on the circuit board, the impedance characteristics of the omnidirectional antenna can be improved across multiple frequency bands and a wider bandwidth. This not only enables bandwidth design of the antenna but also ensures low loss in the impedance matching feed circuit 2, thereby achieving a high-gain design for the omnidirectional antenna.

[0060] In actual use, the omnidirectional antenna receives external signals through connector 1 and then excites and feeds the impedance matching feed circuit 2. The impedance matching feed circuit 2 excites and feeds the first radiating element 7 and the second radiating element 8 through the multi-stage capacitor module 4. The electromagnetic wave of the excitation signal generated by it is finally radiated out through the first radiating element 7 and the second radiating element 8.

[0061] Furthermore, in a specific embodiment of this application, the omnidirectional antenna operates in the VHF / UHF band, and its protective sleeve 11 is made of non-metallic material. Meanwhile, the dimensions LL1, LL2, and LL3 of the cap 10 are preferably 16.0 mm, 2.0 mm, and 18.0 mm, respectively. The total length LL4, total width W6, gap lengths LL5 and LL6, and gap widths G1 and G2 of the first radiating element 7 and the second radiating element 8 are preferably 138.0 mm, 48.5 mm, 61.4 mm, 1.4 mm, and 1.5 mm, respectively. The dimensions of each metal capacitor ring in the multi-stage capacitor module 4, W1, W2, W3, W4, W5, H1, H2, H3, and H4, are preferably 3.8mm, 1.9mm, 1.9mm, 4.1mm, 1.5mm, 1.4mm, 1.25mm, 1.1mm, and 0.9mm, respectively; the inductance and capacitance values ​​of the wound inductor and special cable capacitor in the impedance matching power supply circuit 2 for L1, L2, L3, C1, C2, C3, and C4 are preferably 3.5pF, 4.6pF, 3.4pF, 5.6pF, 167nH, 148nH, and 133nH, respectively.

[0062] like Figure 11 As shown, the omnidirectional antenna designed and fabricated using the above parameters achieves a VSWR of less than 2 with a bandwidth exceeding 79.9%, realizing a wideband design in the VHF / UHF bands. The overall antenna length is 228.0 mm, which is 0.15 times the wavelength corresponding to the lowest operating frequency, achieving miniaturized antenna design. Meanwhile, as... Figure 12 As shown, the gain patterns of the omnidirectional antenna at its center frequency point are horizontal and vertical. It can be seen that the antenna pattern is horizontally omnidirectional with a maximum gain of 0.23 dBi. Furthermore, the entire pattern is relatively symmetrical, achieving a high-gain design in the horizontal omnidirectional direction.

[0063] This invention discloses a broadband miniaturized omnidirectional antenna for terminals. It features a simple structure, high stability, and ease of use. By employing a first radiating element 7 and a second radiating element 8 arranged opposite each other, along with corresponding slots on the first and second radiating elements 7 and 8, a stable coupling structure is formed. This not only reduces the size of the omnidirectional antenna but also ensures stable transmission of the excitation signal electromagnetic wave. Furthermore, by adjusting the dimensions of each metal capacitor ring in the multi-stage capacitor module 4, the impedance characteristics of the omnidirectional antenna are significantly optimized, thereby improving its impedance matching characteristics. Simultaneously, through the corresponding design of each capacitor and inductor in the impedance matching feed circuit 2, the impedance characteristics of the omnidirectional antenna can be improved across multiple frequency bands and a wide bandwidth. This not only enables bandwidth design of the antenna but also ensures low loss in the impedance matching feed circuit 2, thus achieving a high-gain design for the omnidirectional antenna. This design offers excellent economic benefits and has significant potential for widespread application.

[0064] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A broadband miniaturized omnidirectional terminal antenna, characterized in that, include: Impedance matching power supply circuit; It includes at least one inductor and at least one capacitor fixedly mounted on a circuit board, one end of which is fixedly connected to a connector for receiving and transmitting excitation power. Multi-stage capacitor module; It includes multiple metal capacitor rings, one end of which is fixedly connected to the end of the impedance matching feed circuit away from the connector, for optimizing the impedance matching characteristics of the omnidirectional antenna and receiving and transmitting the excitation feed. Radiation module; It includes a first radiating element and a second radiating element arranged at relative intervals. Both are fixedly connected to one end of the multi-stage capacitor module away from the impedance matching power supply circuit. At the same time, the first radiating element and the second radiating element are provided with slots arranged in a triangular pattern through the radiating element. The slots on the two are the same in shape and arranged in opposite directions to form the coupling structure of the radiating module, which is used to receive the excitation power supply to generate an excitation signal and complete horizontal omnidirectional radiation.

2. The broadband miniaturized omnidirectional antenna for terminals according to claim 1, wherein, An insulating interlayer is provided between the first radiating oscillator and the second radiating oscillator. The interlayer has the same shape as the first radiating oscillator and the second radiating oscillator and is used to isolate the first radiating oscillator and the second radiating oscillator.

3. The broadband miniaturized omnidirectional antenna for terminals according to claim 1 or 2, wherein, The first radiating oscillator and the second radiating oscillator are fixed at one end with a cap, and their other ends are fixedly connected to the multi-stage capacitor module with a first fixing block and a second fixing block.

4. The broadband miniaturized omnidirectional antenna for terminals according to claim 3, wherein, The cap has a T-shaped structure and is used to improve the resonance matching of the omnidirectional antenna.

5. The broadband miniaturized omnidirectional antenna for terminals according to claim 3, wherein, The radiation module, the first fixing block, and the second fixing block are provided with protective covers on their outer sides. These covers are made of heat-shrinkable material and are used to wrap and seal the radiation module, the first fixing block, and the second fixing block.

6. The broadband miniaturized omnidirectional antenna for terminals according to any one of claims 1, 2, 4, and 5, wherein, The impedance characteristics of the multi-stage capacitor module are adjusted by changing the size of each of the metal capacitor rings.

7. The broadband miniaturized omnidirectional antenna for terminals according to any one of claims 1, 2, 4, and 5, wherein, The impedance matching feed circuit includes multiple inductors and multiple capacitors fixedly mounted on a circuit board, which adjusts the bandwidth of the omnidirectional antenna by adjusting the inductance and / or capacitance values ​​of each of the inductors and / or capacitors.

8. The broadband miniaturized omnidirectional antenna for terminals according to any one of claims 1, 2, 4, and 5, wherein, The impedance matching power supply circuit and the multi-stage capacitor module are provided with protective sleeves to protect them.

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