A high-gain, low-non-circularity omnidirectional antenna based on printed oscillators

Abstract

The present invention belongs to the field of wireless communication technology and discloses a high-gain, low-non-circularity omnidirectional antenna based on a printed oscillator. The antenna comprises a radome, a dielectric base, a radiating dielectric plate, and a coaxial cable assembly. The radome and radiating dielectric plate are both mounted on the dielectric base, and the radiating dielectric plate is disposed within the radome. The shape and size of the radiating dielectric plate match the radome. Metal radiating patches and feeder lines are printed on both sides of the radiating dielectric plate. The coaxial cable assembly is disposed beneath the dielectric base and electrically connected to the metal radiating patches and feeder lines for power feeding. The present invention is suitable for airborne environments and offers the advantages of high gain and low non-circularity, as well as wide bandwidth and a stable radiation pattern, thereby improving the communication stability of airborne communication systems.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless communications, and in particular relates to a high-gain, low-out-of-roundness omnidirectional antenna based on a printed vibrator. Background Art

[0002] Airborne omnidirectional antennas are an important component of aircraft communication systems. The electrical performance of the antenna determines the communication distance and stability of the entire communication system, and the research on airborne antennas is of great significance.

[0003] Due to their requirements for aerodynamic performance, airborne antennas mostly use flat printed antennas, which are often made into wing shapes. However, the impact of the flat structure and the carrier on the antenna can cause the horizontal plane radiation pattern to be distorted and produce large non-circularity, which makes it difficult to meet the actual needs of airborne antennas in complex flight postures.

[0004] In the existing technology, the designed blade-shaped omnidirectional antenna mostly adopts the resistance loading method to widen the working bandwidth of the antenna and reduce the antenna height. However, this method will also lose gain, resulting in lower gain, and will produce large non-circularity, reducing the communication stability of the system.

[0005] In summary, the problems with the existing technology are: in order to meet the aerodynamic performance of airborne antennas, existing airborne omnidirectional antennas cannot simultaneously achieve wide bandwidth, high gain and small non-circularity of the radiation pattern. When the bandwidth is insufficient, the frequency performance at the edge of the band is poor, which limits its application in the field of wireless communications. Summary of the Invention

[0006] In response to the shortcomings of the existing technology, the present invention provides a high-gain, low-non-circularity omnidirectional antenna based on a printed vibrator, which is used to solve the problems of existing airborne omnidirectional antennas that cannot simultaneously achieve wide bandwidth, high gain and small non-circularity of the radiation pattern, poor frequency performance at the edge of the band when the bandwidth is insufficient, and poor communication stability of the system, which limits its application in the field of wireless communications.

[0007] To achieve the purpose of the present invention, the present invention provides the following technical solutions:

[0008] A high-gain, low-non-circularity omnidirectional antenna based on a printed vibrator includes a radome, a dielectric base, a radiating dielectric plate, and a coaxial cable assembly. The radome and the radiating dielectric plate are both mounted on the dielectric base, and the radiating dielectric plate is disposed within the radome. The shape and size of the radiating dielectric plate match those of the radome. Metal radiating patches and feed lines are printed on both sides of the radiating dielectric plate. The coaxial cable assembly is disposed below the dielectric base, and the coaxial cable assembly, the metal radiating patch, and the feed line are electrically connected to achieve feeding.

[0009] Furthermore, as a preferred technical solution, the antenna cover is a knife-shaped antenna cover, the cover body of which is integrally formed using FR4 material, and the bottom of the cover body has a cover opening, and the antenna cover is fixed to the dielectric base through the cover opening.

[0010] Furthermore, as a preferred technical solution, the dielectric base is machined from FR4 material, and the antenna cover and the radiation dielectric plate are fixed to the dielectric base through a metal frame and metal screws.

[0011] Furthermore, as a preferred technical solution, the radiation dielectric plate adopts a polytetrafluoroethylene glass fiber cloth substrate with a dielectric constant of 2.55, and the substrate is copper-clad on both sides.

[0012] Furthermore, as a preferred technical solution, the cavity between the radiation dielectric plate and the antenna cover is filled with foaming material.

[0013] Furthermore, as an optimal technical solution, series feeding lines are printed on both sides of the radiating dielectric plate, and evenly arranged parasitic metal patches and trapezoidal gradient metal radiating patches are printed on the radiating dielectric plates on both sides of the series feeding lines to form a 4-element symmetrical dipole antenna array.

[0014] Furthermore, as a preferred technical solution, the lengths of the parasitic metal patches are different, and the length of each parasitic metal patch is 0.2λ0 to 0.27λ0, where λ0 is the free space wavelength of the center frequency.

[0015] Furthermore, as a preferred technical solution, the upper base of the trapezoidal gradient metal radiation patch is 0.02λ0, the lower base is 0.04λ0, and the height is 0.2λ0, where λ0 is the free space wavelength of the center frequency.

[0016] Furthermore, as a preferred technical solution, the front and back sides of the radiation dielectric plate are respectively printed with a series feed line and a feed balun, the inner conductor of the coaxial cable assembly is electrically connected to the series feed line printed on the front side of the radiation dielectric plate, and the outer conductor of the coaxial cable assembly is connected to the feed balun printed on the back side of the radiation dielectric plate.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] (1) The present invention expands the bandwidth of the antenna by printing the oscillator on both sides of the radiation dielectric plate. At the same time, by designing a symmetrical oscillator with a trapezoidal gradient shape and a wide-band feeding balun structure, the impedance matching is further improved and the impedance bandwidth of the antenna is widened.

[0019] (2) The present invention prints series feed lines on both sides of the radiation dielectric plate, and prints evenly arranged parasitic metal patches and trapezoidal gradient metal radiation patches on the radiation dielectric plates on both sides of the series feed lines to form a 4-element symmetrical dipole antenna array, which effectively improves the gain of the antenna and achieves a gain of 4.9dB, thereby achieving high gain of the antenna. By optimizing the lengths of different parasitic metal patches, the non-circularity of the omnidirectional radiation pattern is reduced, and the maximum non-circularity is 0.9dB, truly achieving wide bandwidth, high gain and small non-circularity of the radiation pattern, thereby improving the stability of airborne communications and facilitating better application in the field of wireless communications.

[0020] (3) The present invention effectively solves the problem that existing airborne omnidirectional antennas cannot simultaneously achieve wide bandwidth, high gain and small non-circularity of the radiation pattern, and the frequency performance at the edge of the band is poor when the bandwidth is insufficient. At the same time, the present invention achieves good aerodynamic performance of the airborne antenna, and the overall structural strength of the antenna is high, which can be used for a long time and has great practical significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the structure of a high-gain, low-out-of-roundness omnidirectional antenna based on a printed vibrator according to the present invention;

[0022] Figure 2 yes Figure 1 Side view of

[0023] Figure 3 It is a schematic diagram of the positional relationship between the series feeder circuit, the metal radiation patch, and the parasitic metal patch of the present invention;

[0024] Figure 4 It is a voltage standing wave ratio curve diagram of the present invention;

[0025] Figure 5 is a gain curve diagram of the present invention;

[0026] Figure 6 It is the azimuth radiation pattern of the present invention at the frequency of 1.45 GHz;

[0027] Figure 7 It is the azimuth radiation pattern of the present invention at the 1.6 GHz frequency point;

[0028] Figure 8 This is the azimuth radiation pattern of the present invention at the 1.75 GHz frequency point.

[0029] The names corresponding to the reference numerals in the figure are: 1. antenna cover, 2. dielectric base, 3. radiation dielectric plate, 4. printed metal patch and feed line, 5. coaxial cable assembly, 41. series feed line, 42. metal radiation patch, 43. parasitic metal patch. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0031] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limiting the present invention.

[0032] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "provided with," "mounted / connected," and "connected" should be understood in a broad sense. For example, "connected" can mean a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be internal communication between two components. Those skilled in the art will be able to understand the specific meanings of the above terms in the present invention in specific circumstances.

[0033] like Figure 1 、 Figure 2 As shown, an embodiment of the present invention provides a high-gain, low-non-circularity omnidirectional antenna based on a printed vibrator, comprising an antenna cover 1, a dielectric base 2, a radiation dielectric plate 3, and a coaxial cable assembly 5. The antenna cover 1 and the radiation dielectric plate 3 are both mounted on the dielectric base 2, and the radiation dielectric plate 3 is arranged in the antenna cover 1. The shape and size of the radiation dielectric plate 3 match those of the antenna cover 1. Metal radiation patches and feed lines 4 are printed on both sides of the radiation dielectric plate 3. The coaxial cable assembly 5 is arranged below the dielectric base 2, and the coaxial cable assembly 5 is electrically connected to the metal radiation patch and feed line 4 to achieve feeding.

[0034] Preferably, the radome 1 in this embodiment is a blade-shaped radome, with its housing integrally formed from FR4 material. A hood opening is formed at the bottom of the housing, and the radome 1 is secured to the dielectric base 2 via the hood opening. The blade-shaped radome minimizes wind resistance, thereby reducing the impact on the carrier's aerodynamic performance. The integral FR4 housing ensures the overall structural strength of the antenna, ensuring long-term, break-resistant operation. FR4 material, primarily composed of epoxy resin, fiberglass cloth, and fillers, self-extinguishes when burned, resulting in excellent flame resistance. Furthermore, it offers stable electrical insulation, excellent flatness, a smooth surface, and a pit-free design, ensuring standard thickness tolerances. These characteristics make it ideal for use in products requiring high-performance electronic insulation. It also exhibits excellent heat resistance, flame retardancy, mechanical strength, and corrosion resistance.

[0035] like Figure 4 The figure shows the measured voltage standing wave ratio of the present invention. It can be seen from the figure that the voltage standing wave ratio of the present invention is less than 2, which means that the standing wave of the present invention is good and can fully meet the requirements of the antenna.

[0036] Preferably, the radiation dielectric plate 3 of this embodiment uses a polytetrafluoroethylene glass fiber cloth substrate with a dielectric constant of 2.55, and the substrate is copper-clad on both sides.

[0037] In order to enhance the structural strength of the antenna and reduce the impact on the radiation performance of the antenna, the dielectric base 2 of this embodiment is machined from FR4 material, and the antenna cover 1 and the radiation dielectric plate 3 are fixed to the dielectric base 2 by a metal frame and metal screws.

[0038] Preferably, the cavity between the radiation dielectric plate 3 and the antenna cover 1 of this embodiment is filled with foaming material to prevent the antenna from being deformed due to the movement of the carrier and affecting the electrical performance.

[0039] like Figure 3 As shown, the radiation dielectric plate 3 of this embodiment is printed with series feed lines 41 on both sides, and the radiation dielectric plates 2 on both sides of the series feed line 41 are printed with evenly arranged parasitic metal patches 43 and trapezoidal gradient metal radiation patches 42, forming a 4-element symmetrical dipole antenna array. Specifically, the copper-clad areas on the front and back sides of the radiation dielectric plate 3 are printed metal patches and series feed lines, and the antenna is fed by a series feed network, which reduces the space occupied; at the same time, since the metal radiation patches 42 are evenly arranged on both sides of the feeding circuit, the trapezoidal gradient metal radiation patches 42 together with the parasitic metal patches 43 form a 4-element symmetrical dipole antenna array, which are printed on the front and back sides of the substrate and radiate through electric field coupling, which can broaden the bandwidth of the antenna and improve the gain of the antenna, so that the gain reaches 4.9dB, and an omnidirectional radiation pattern with good roundness is achieved, as shown in FIG. Figure 5-Figure 8 shown.

[0040] It should be noted that the four-element symmetrical dipole antenna array consists of four symmetrical dipoles with a fixed element spacing. Two metal radiating patches 42 form a symmetrical dipole, corresponding to a parasitic metal patch 43. The uniform arrangement of the aforementioned parasitic metal patches 42 and the trapezoidal gradient metal radiating patch 43 typically refers to an axial element spacing of 0.35λ0, where λ0 is the free-space wavelength of the center frequency. The innovation of this invention lies in the combination of the dipole array and the parasitic metal patch, as well as the optimization of the parasitic metal patch for out-of-roundness.

[0041] In this embodiment, the lengths of the parasitic metal patches are different. The length of each parasitic metal patch is 0.2λ0~0.27λ0, where λ0 is the free space wavelength of the center frequency. The upper base of the trapezoidal gradient metal radiation patch is 0.02λ0, the lower base is 0.04λ0, and the height is 0.2λ0. The trapezoidal gradient metal radiation patch can further broaden the impedance bandwidth of the antenna, and the length of each parasitic metal patch is designed to be within the range of 0.2λ0~0.27λ0, which has a guiding effect. By optimizing the lengths of different parasitic patches, the non-circularity of the antenna radiation pattern can be reduced. Specifically, the length optimization of the parasitic patch is automatically optimized by the simulation software after a given initial value, and the optimization target is the non-circularity of the antenna. This is very easy to implement for those skilled in the art, so its principles and effects will not be elaborated on in detail.

[0042] In this embodiment, a series feed line and a feed balun are printed on the front and back of the radiating dielectric plate 3, respectively. The inner conductor of the coaxial cable assembly 5 is electrically connected to the series feed line printed on the front of the radiating dielectric plate 3, and the outer conductor of the coaxial cable assembly 5 is connected to the feed balun printed on the back of the radiating dielectric plate 3. This design can improve impedance matching and widen the impedance bandwidth of the antenna.

[0043] The above description is only 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 in the scope of protection of the present invention.

Claims

1. A high-gain, low-out-of-roundness omnidirectional antenna based on a printed vibrator, characterized in that: The invention comprises an antenna cover (1), a dielectric base (2), a radiation dielectric plate (3) and a coaxial cable assembly (5), wherein the antenna cover (1) and the radiation dielectric plate (3) are both mounted on the dielectric base (2), and the radiation dielectric plate (3) is arranged in the antenna cover (1), and the shape and size of the radiation dielectric plate (3) match those of the antenna cover (1), and the front and back surfaces of the radiation dielectric plate (3) are both printed with metal radiation patches and feed lines (4), and the coaxial cable assembly (5) is arranged below the dielectric base (2), and the coaxial cable assembly (5) is electrically connected to the metal radiation patches and feed lines (4) to achieve feeding; Series feed circuits are printed on both sides of the radiation dielectric plate (3), and evenly arranged parasitic metal patches and trapezoidal gradient metal radiation patches are printed on the radiation dielectric plates (3) on both sides of the series feed circuit, forming a 4-element symmetrical dipole antenna array; The lengths of the parasitic metal patches are different, and the length of each parasitic metal patch is 0.2λ0 to 0.27λ0, where λ0 is the free space wavelength of the center frequency; The upper base of the trapezoidal gradient metal radiation patch is 0.02λ0, the lower base is 0.04λ0, and the height is 0.2λ0, where λ0 is the free space wavelength of the center frequency; The front and back surfaces of the radiation dielectric plate (3) are respectively printed with a series feed line and a feed balun; the inner conductor of the coaxial cable assembly (5) is electrically connected to the series feed line printed on the front surface of the radiation dielectric plate (3); and the outer conductor of the coaxial cable assembly (5) is connected to the feed balun printed on the back surface of the radiation dielectric plate (3).

2. The high-gain, low-out-of-roundness omnidirectional antenna based on a printed vibrator according to claim 1, characterized in that: The antenna cover (1) is a knife-shaped antenna cover, the cover body of which is integrally formed using FR4 material, and the bottom of the cover body is provided with a cover opening, and the antenna cover (1) is fixed on the dielectric base (2) through the cover opening.

3. The high-gain, low-non-circularity omnidirectional antenna based on a printed vibrator according to claim 1, characterized in that: The dielectric base (2) is machined from FR4 material, and the antenna cover (1) and the radiation dielectric plate (3) are fixed to the dielectric base (2) via a metal frame and metal screws.

4. The high-gain, low-non-circularity omnidirectional antenna based on a printed vibrator according to claim 1, characterized in that: The radiation medium plate (3) adopts a polytetrafluoroethylene glass fiber cloth substrate with a dielectric constant of 2.55, and the substrate is copper-clad on both sides.

5. The high-gain, low-non-circularity omnidirectional antenna based on a printed vibrator according to claim 1, characterized in that: The cavity between the radiation medium plate (3) and the antenna cover (1) is filled with foaming material.

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