High gain omni-directional whip antenna with equal section series sleeve structure

Abstract

This invention discloses a high-gain omnidirectional whip antenna with an equal-section series sleeve structure, addressing the problems of narrow bandwidth, low gain, and poor structural stability in traditional omnidirectional whip antennas. The antenna includes a radome, multiple radiating sleeves, multiple insulating isolators, and a coaxial feed line. The radiating sleeves are arranged in series along the axial direction to form multiple radiating elements. Insulating isolators are placed between adjacent sleeves for limiting position, preventing swaying, and providing electrical isolation, thereby improving structural stability. The coaxial feed line provides excitation signals from the bottom to each radiating element, forming a continuous current path. All radiating elements employ in-phase excitation, effectively enhancing the vertical radiation main lobe and improving directivity. This antenna exhibits excellent impedance matching characteristics in the 0.74–0.97 GHz frequency band, achieving a peak gain of 8 dBi, significantly improving long-distance communication capabilities and signal penetration performance, and is suitable for high-reliability wireless coverage requirements in Sub-1 GHz multi-standard communication scenarios.

Description

Technical Field

[0001] This utility model relates to the field of wireless communication antenna technology, specifically to a broadband high-gain omnidirectional whip antenna suitable for Sub-1 GHz multi-standard communication systems. Background Technology

[0002] In fields such as wireless communication, emergency response, telemetry and remote control, and IoT systems, the Sub-1 GHz communication band (i.e., the ultra-high frequency band below 1 GHz) has become an important frequency band for long-distance and complex environment communication due to its excellent diffraction capability, low path loss, and wide coverage. This band covers several mainstream communication standards, including: GSM 900 (890–960 MHz); LTE Band 28 (703–748 MHz), Band 8 (880–915 MHz); LoRa / ISM 868 / 915 MHz; and various UHF private network communication systems.

[0003] In the aforementioned frequency bands, whip antennas are widely used in vehicle-mounted equipment, emergency communication terminals, and IoT base stations due to their simple structure, stable radiation, and strong omnidirectionality. However, traditional whip antennas suffer from low gain and limited bandwidth, making it difficult to simultaneously meet the comprehensive performance requirements of multiple standards, wide-band coverage, and high-reliability communication.

[0004] Especially in the Sub-1 GHz mid-frequency band (0.67–1.1 GHz), in order to obtain higher radiation gain, the antenna length often needs to be designed to be more than several operating wavelengths, resulting in problems such as longer structural size, inconvenient installation, and decreased mechanical stability, which seriously restricts engineering applications.

[0005] Therefore, there is an urgent need to design a whip antenna with a structural length within an acceptable range for engineering purposes, while possessing broadband coverage and high gain performance, in order to meet the needs of multi-mode wireless communication in complex environments. Utility Model Content

[0006] The purpose of this invention is to provide a broadband, high-gain omnidirectional whip antenna that solves the problems of narrow bandwidth, low gain, and poor structural adaptability of traditional whip antennas.

[0007] According to one aspect of an embodiment, a whip antenna includes: an radome made of a non-conductive material for covering and protecting the internal structure of the antenna; a coaxial feed line disposed within the radome, including a center conductor, an outer conductor, and a dielectric layer between them; a plurality of radiating sleeves fitted onto the coaxial feed line, each radiating sleeve being made of metal and being a hollow cylinder, wherein the top radiating sleeve is electrically connected to the center conductor of the coaxial feed line, and the remaining radiating sleeves are electrically connected to the outer conductor of the coaxial feed line; and a plurality of radiating elements, each of which... The radiating element is composed of two adjacent radiating sleeves, with an insulating isolator between the two adjacent radiating sleeves. The outer conductor of the coaxial feed line in the area where the insulating isolator is located is stripped, so that the two radiating sleeves of each radiating element are electrically isolated. The base, made of metal, is located at the bottom of the antenna and is electrically connected to the outer conductor of the coaxial feed line. The feed port is located outside the antenna cover, with the outer conductor of the feed port electrically connected to the base and the inner conductor of the feed port electrically connected to the center conductor of the coaxial feed line.

[0008] In some examples, all of the said radiating sleeves have the same diameter and length.

[0009] In some examples, the outer diameter of the radiating sleeve is smaller than the inner diameter of the radome.

[0010] In some examples, the insulating spacer is a rubber ring.

[0011] In some examples, the outer diameter of the insulating isolator matches the inner diameter of the radome.

[0012] In some examples, the insulating isolator is interference-fitted with the radome to mechanically limit the radiating element.

[0013] In some examples, one end of the top radiating sleeve is electrically connected to the center conductor of the coaxial feed.

[0014] In some examples, one end of the radiating sleeve at the remaining locations is electrically connected to the outer conductor of the coaxial feed line via an electrical connection interface, while the other end is open and not in electrical contact with the coaxial feed line.

[0015] In some examples, the antenna exhibits high vertical gain and omnidirectional horizontal radiation characteristics within the operating frequency band of 0.74–0.97 GHz.

[0016] In some examples, the peak gain is as high as 8 dBi.

[0017] The whip antenna of this invention is an antenna array composed of multiple identical radiating elements connected in series. Each radiating element is sequentially fed along the axial direction, and the overall radiation performance is enhanced through ordered structural stacking. While maintaining a compact shape, the antenna array achieves broadband coverage of 0.74–0.97 GHz and a radiation gain of up to 8 dBi, meeting the performance requirements of multi-standard long-distance communication in the Sub-1 GHz band.

[0018] This utility model uses an annular rubber pad as an isolation and support structure between the sleeves, and the outer diameter of the rubber pad matches the inner diameter of the antenna cover. It also has three functions: electrical insulation, structural positioning, and anti-shaking limit, which significantly improves the stability and reliability of the antenna in complex environments such as vibration and impact.

[0019] All semi-open metal sleeves and rubber gasket components are of uniform size and standardized design, possessing good structural consistency, ease of assembly, and adaptability to mass production, facilitating engineering implementation and industrialization of products.

[0020] This invention is applicable to scenarios such as emergency communication vehicle-mounted equipment, LoRa / NB-IoT base stations, UHF private network systems, small relay communication devices, and remote telemetry communication nodes, and has good promotional value in modern wireless communication systems. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a high-gain omnidirectional whip antenna with an equal-section series sleeve structure in one embodiment of the present invention.

[0022] Figure 2 yes Figure 1 The diagram shows the antenna after the radome has been removed.

[0023] Figure 3 yes Figure 2 The diagram shows a cross-sectional view of the antenna.

[0024] Figure 4 yes Figure 3 Enlarged view of the radiating element within the dashed box.

[0025] Figure 5 This is a simulation diagram of the S-parameters and gain of the antenna in one embodiment of this utility model.

[0026] Figure 6 This is a simulation diagram of the radiation pattern of the antenna in one embodiment of this utility model. Detailed Implementation

[0027] Figure 1 , Figure 2 and Figure 3A broadband high-gain omnidirectional whip antenna 1 is demonstrated. The term "broadband" means that the antenna 1 can cover the frequency bands corresponding to multiple mainstream communication standards, including GSM900, LTE Band 28, Band 8, LoRa, ISM and other standards, meeting the requirements of multi-standard coexistence and frequency reuse.

[0028] like Figures 1-3 As shown, the antenna 1 includes an antenna cover 11, a radiating sleeve 12, an insulating isolator 13, a coaxial feed line 14, a base 15, and a feed port 16.

[0029] like Figure 4 As shown, the coaxial feeder 14 includes a center conductor 141, an outer conductor 142, and a dielectric layer 143 located between the two.

[0030] The radiating sleeve 12 is made of conductive metal material and has a hollow cylindrical structure, such as a cylinder. There are multiple sleeves 12, all with the same size, diameter and length, which are arranged in series on the coaxial feed line 14.

[0031] The top radiating sleeve 12 is electrically connected to the center conductor 141 of the coaxial feed line 14, while the remaining radiating sleeves 12 are electrically connected to the outer conductor 142 of the coaxial feed line 14. One end of the top radiating sleeve 12 is electrically connected to the center conductor 141 of the coaxial feed line 14, for example, by welding or threading. The remaining radiating sleeves 12 have one end electrically connected to the outer conductor 142 of the coaxial feed line 14 via an electrical connection interface, while the other end remains open and not in electrical contact with the coaxial feed line 14. The electrical interface is a hole at the end of the radiating sleeve 12 that mates with the coaxial feed line 14. When the radiating sleeve 12 is fitted onto the coaxial feed line 14, this hole remains in contact with the coaxial feed line 14, enabling the transmission of radio frequency signals.

[0032] Two adjacent sleeves 12 form a group, constituting a radial unit / structure. Figure 4 The area within the dashed box represents a radiating element. An insulating isolator 13 is provided between two adjacent radiating sleeves 12, and the outer conductor 142 of the coaxial feed line 14 in the area where the insulating isolator 13 is located is stripped, so that the two radiating sleeves of each radiating element are electrically isolated. "Adjacent" means that the distance between the two sleeves 12 of the radiating element is usually less than 0.1 times the wavelength.

[0033] All radiating elements are fed in series in phase to achieve omnidirectional high-gain radiation. Figure 1 and Figure 2 The embodiment shown has four radiating units, but is not limited thereto. Those skilled in the art can determine the number of sleeves 12 and radiating units according to the specific application scenario.

[0034] The insulating isolator 13 can be a rubber ring, the outer diameter of which is the same as the inner diameter of the radome 11. While ensuring electrical isolation between the two radiating sleeves 12 within the radiating element, it also provides limiting positioning and anti-sway support for the overall radiator, improving the mechanical reliability and environmental adaptability of the antenna. The insulating isolator 13 and the radome 11 are generally fitted with an interference fit.

[0035] The radome 11 is an external non-conductive protective shell that wraps around the aforementioned radiating structure and insulating rubber ring. It is used to prevent dust, moisture, or external force damage from entering the antenna, thereby improving the structural lifespan and outdoor application capabilities.

[0036] The base 15 is made of metal and is located at the bottom of the antenna 1. It can be threadedly connected to the antenna cover 11. The base 15 is electrically connected to the outer conductor of the coaxial feed line 14. Specifically, the base 15 is fitted onto the coaxial feed line 14 and maintains contact with its outer conductor 142.

[0037] The feed port 16 is located outside the radome 11 and is connected to the coaxial feed line 14 to transmit radio frequency signals to the radiating structure, providing stable excitation for the antenna. Specifically, the outer conductor of the feed port 16 is electrically connected to the base 15 (e.g., threaded connection or welding), and the inner conductor of the feed port 16 is electrically connected to the center conductor 141 of the coaxial feed line 14 (e.g., threaded connection or welding).

[0038] A coaxial feeder provides excitation signals to each radiating element from the bottom, forming a continuous current path. All radiating elements use in-phase excitation, effectively enhancing the vertical radiation main lobe and improving directivity.

[0039] like Figure 5 As shown, the antenna exhibits good impedance matching performance in the simulation: the reflection coefficient (S11) is less than -10dB in the range of 0.74–0.97 GHz, indicating that the structure has broadband operation capability in the mainstream Sub-1 GHz communication band. Figure 6 As shown, the antenna exhibits omnidirectional radiation pattern in the horizontal plane and good directivity in the vertical plane within this frequency band, with a peak gain of up to 8 dBi, significantly improving long-distance communication capabilities and signal penetration performance, and meeting the practical needs of long-distance, multi-mode wireless communication scenarios.

[0040] The antenna's overall structure adopts a standardized design, with all metal sleeves 2 and rubber pads 3 being of uniform size. This simplifies manufacturing and assembly processes, making it suitable for mass industrial production. If four radiating elements are used, the overall length is approximately 1.3 meters, demonstrating good engineering practicality and promotional value.

Claims

1. A whip antenna, characterized by include: The radome, made of non-conductive material, is used to cover and protect the internal structure of the antenna; A coaxial feed line is disposed inside the radome and includes a center conductor, an outer conductor, and a dielectric layer located between the two. Multiple radiating sleeves are fitted onto the coaxial feed line. Each radiating sleeve is made of metal and is a hollow cylinder. The top radiating sleeve is electrically connected to the center conductor of the coaxial feed line, and the radiating sleeves at other positions are electrically connected to the outer conductor of the coaxial feed line. Multiple radiating units, each radiating unit consisting of two adjacent radiating sleeves, with an insulating isolator between the two adjacent radiating sleeves, and the outer conductor of the coaxial feeder in the area where the insulating isolator is located is stripped, so that the two radiating sleeves of each radiating unit are electrically isolated; The base, made of metal, is located at the bottom of the antenna and is electrically connected to the outer conductor of the coaxial feed line; The power supply port is located outside the radome. The outer conductor of the power supply port is electrically connected to the base, and the inner conductor of the power supply port is electrically connected to the center conductor of the coaxial feed line.

2. The whip antenna according to claim 1, characterized in that All of the aforementioned radiating sleeves have the same diameter and length.

3. The whip antenna according to claim 2, characterized in that The outer diameter of the radiating sleeve is smaller than the inner diameter of the antenna radome.

4. The whip antenna according to claim 1, wherein The insulating isolation component is a rubber ring.

5. The whip antenna according to claim 4, characterized in that The outer diameter of the insulating isolator matches the inner diameter of the radome.

6. The whip antenna according to claim 5, characterized in that The insulating isolator and the radome form an interference fit to achieve mechanical limiting of the radiating unit.

7. The whip antenna according to claim 1, wherein One end of the top radiating sleeve is electrically connected to the center conductor of the coaxial feeder.

8. The whip antenna according to claim 1, wherein One end of the radiating sleeve at the remaining positions is electrically connected to the outer conductor of the coaxial feed line via an electrical connection interface, while the other end is open and not in electrical contact with the coaxial feed line.

9. The whip antenna according to any one of claims 1-8, characterized in that, The antenna exhibits high vertical gain and omnidirectional horizontal radiation characteristics within the operating frequency band of 0.74–0.97 GHz.

10. The whip antenna according to claim 9, characterized in that Peak gain up to 8dBi.

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