An ultra-wideband harmonic rejection dipole antenna

Abstract

The application discloses an ultra-wideband harmonic suppression dipole antenna, which comprises a dielectric substrate and two dipole arms with structural symmetry, an upper arm and a lower arm, the upper arm and the lower arm are respectively printed on the upper and lower surfaces of the dielectric substrate, and the upper arm and the lower arm are connected by using a through hole at the center of the dipole antenna; the fifth mode is regulated by loading a branch perpendicular to the dipole arm, so that the current zero point of the fifth mode is coincided with the current zero point of the third mode; a one-to-two T-shaped microstrip power divider is used for feeding, the output end of the power divider is connected to the common zero point position of the third resonant mode and the fifth resonant mode, so that the third resonant mode and the fifth resonant mode are filtered; and the parallel distributed capacitance at the dipole feeding point is used for filtering the seventh mode and the ninth mode. The harmonic suppression frequency of the antenna covers 10f0. At the center frequency of 1.2 GHz, the antenna has an 8-shaped E-plane and an omni-directional H-plane radiation pattern.

Description

Technical Field

[0001] This invention relates to the field of dipole antenna technology, and more specifically to an ultra-wide stopband harmonic suppression dipole antenna. Background Technology

[0002] Harmonic suppression antennas can effectively suppress harmonics generated by the nonlinearity or higher-order modes of a system, and have important application value in the current stage of increasingly crowded spectrum.

[0003] The main problems faced by current harmonic suppression antennas are as follows: (1) narrow stopband bandwidth, with stopband coverage generally less than 3f0 (f0 corresponds to the antenna's operating center frequency); (2) harmonic suppression effect only in the main radiation direction. Based on the above problems, it is necessary to make improvements. Summary of the Invention

[0004] The purpose of this invention is to provide an ultra-wide stopband harmonic suppression dipole antenna. Based on the dipole as a prototype, and using multi-point feeding technology, stub loading technology and capacitor loading technology, an omnidirectional harmonic suppression dipole antenna with a stopband coverage of 10f0 is provided.

[0005] To achieve the objectives of this invention, the technical solution provided by this invention is as follows:

[0006] An ultrawide stopband harmonic suppression dipole antenna is disclosed. The antenna comprises a dielectric substrate and two symmetrically structured dipole arms, an upper arm and a lower arm, which are printed on the upper and lower surfaces of the dielectric substrate, respectively. A through-hole connects the upper and lower arms at the center of the dipole antenna. The fifth mode is modulated by loading a stub perpendicular to the dipole arm, causing the current zero point of the fifth mode to coincide with that of the third mode. A 1-to-2 T-type microstrip power divider is used for feeding, with the output of the power divider connected to the common zero point of the third and fifth resonant modes, thus filtering out the third and fifth resonant modes. A distributed capacitor is connected in parallel at the antenna feed point to construct a high-pass branch, short-circuiting the dipole arms at the frequencies of the seventh and ninth resonant modes, thereby filtering out these modes. The through-hole diameter is 1 mm, and the length of the dipole half-arm is L. d The length is 45mm, and the distance L between the stub loading position and the dipole center is... s The distance L between the dipole feed position and the dipole center is 30mm. f The length of the distributed capacitance is 15mm. c It is 4mm, and the length of the half branch is L. a The dipole arm width is 15mm, and the dipole arm width is W. d It is 2mm.

[0007] The dielectric substrate used is TLY-5 with a thickness of 0.787 mm.

[0008] Compared with existing technologies, the antenna of this invention operates at a center frequency f0 of 1.2 GHz, and has only one resonant point within the 0-12 GHz frequency range. The antenna's harmonic suppression frequency covers 10f0. At a center frequency of 1.2 GHz, the antenna exhibits a figure-eight E-plane and an omnidirectional H-plane radiation pattern. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the structure of an embodiment of this application;

[0010] Figure 2 This is a schematic diagram of the key dimensions of the upper arm of the ultrawide stopband harmonic suppression dipole antenna in the embodiments of this application;

[0011] Figure 3 This is a schematic diagram showing the simulated and measured reflection coefficients;

[0012] Figure 4 Figure (a) shows the simulated and measured radiation patterns; Figure (b) shows the E-plane and Figure (a) shows the H-plane. Detailed Implementation

[0013] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0014] like Figures 1-2 As shown, this application provides an ultra-wideband stopband harmonic suppression dipole antenna. The antenna includes a dielectric substrate and two symmetrical dipole arms, an upper arm and a lower arm, which are printed on the upper and lower surfaces of the dielectric substrate, respectively. A through-hole connects the upper and lower arms at the center of the dipole antenna. The fifth mode is modulated by loading a stub perpendicular to the dipole arm, so that the current zero point of the fifth mode coincides with the current zero point of the third mode. A 1-to-2 T-type microstrip power divider is used for feeding, and the output of the power divider is connected to the common zero point of the third and fifth resonant modes, thereby filtering out the third and fifth resonant modes. A distributed capacitor is connected in parallel at the antenna feed point to construct a high-pass branch, so that the dipole arm is short-circuited at the frequencies of the seventh and ninth resonant modes, thereby filtering out the seventh and ninth resonant modes. The diameter of the through-hole is 1 mm, and the length of the dipole half-arm is L. d The length is 45mm, and the distance L between the stub loading position and the dipole center is... s The distance L between the dipole feed position and the dipole center is 30mm. f The length of the distributed capacitance is 15mm. cIt is 4mm, and the length of the half branch is L. a The dipole arm width is 15mm, and the dipole arm width is W. d It is 2mm.

[0015] The dielectric substrate used is TLY-5 with a thickness of 0.787 mm.

[0016] It should be noted that this invention adjusts the fifth-order resonant mode by adding a stub at the maximum value of the third-order resonant mode current, bringing the zero point of the fifth-order resonant mode current closer to the zero point of the third-order resonant mode current. The stub length L is adjusted. a At 15mm, the current zero points of the fifth and third resonant modes coincide. A microstrip power divider is used for feeding, with its output connected to the common current zero point of both the third and fifth resonant modes, thus filtering out these modes. An open-circuit parallel double conductor is connected at the feed point to form a distributed capacitance. The size of the distributed capacitance can be adjusted by the length of the open-circuit parallel double conductor. When L... c At a length of 4mm, the best suppression effect on the seventh and ninth resonant modes was achieved. Figure 3 As can be seen, by comprehensively utilizing multi-feed technology, stub loading technology, and distributed capacitance loading technology, the harmonic suppression dipole antenna proposed in this invention has a center frequency of 1.2 GHz and a stopband frequency coverage up to 12 GHz. The radiation patterns of the antenna's E-plane and H-plane are shown below. Figure 4 As shown in (a) and (b), the antenna has a figure-eight E-plane radiation pattern and an omnidirectional H-plane radiation pattern.

[0017] This invention relates to a dipole antenna with an ultra-wide stopband, and more particularly to using stub loading technology to adjust the zero point of the fifth resonant mode to coincide with the current zero point of the third mode, combining multi-point feeding technology to filter out the third and fifth resonant modes, and using distributed capacitance loading technology to filter out the seventh and ninth resonant modes.

[0018] Finally, it should be noted that the above embodiments are merely illustrative and explanatory of the present invention, and are not intended to limit the present invention to the scope of the described embodiments. Furthermore, those skilled in the art will understand that the present invention is not limited to the above embodiments, and many more variations and modifications can be made based on the teachings of the present invention, all of which fall within the scope of protection claimed by the present invention.

Claims

1. An ultra-wide stopband harmonic suppression dipole antenna, characterized in that, The antenna comprises a dielectric substrate and two symmetrical dipole arms, an upper arm and a lower arm, which are printed on the upper and lower surfaces of the dielectric substrate, respectively. A through-hole connects the upper and lower arms at the center of the dipole antenna. The fifth mode is modulated by loading a stub perpendicular to the dipole arm, causing the current zero point of the fifth mode to coincide with that of the third mode. A 1-to-2 T-type microstrip power divider is used for feeding, with its output connected to the common zero point of both the third and fifth resonant modes, thus filtering out these modes. A distributed capacitor is connected in parallel at the antenna's feed point to construct a high-pass branch, short-circuiting the dipole arms at the frequencies of the seventh and ninth resonant modes, thereby filtering out these modes. The through-hole diameter is 1 mm, and the length of each dipole half-arm is L. d The length is 45mm, and the distance L between the stub loading position and the dipole center is... s The distance L between the dipole feed position and the dipole center is 30mm. f The length of the distributed capacitance is 15mm. c It is 4mm, and the length of the half branch is L. a The dipole arm width is 15mm, and the dipole arm width is W. d It is 2mm.

2. The ultra-wide stopband harmonic suppression dipole antenna according to claim 1, characterized in that, The dielectric substrate used is TLY-5 with a thickness of 0.787 mm.

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