Quasi TM11 mode-based low-profile four-feed omnidirectional antenna

Abstract

The low-profile four-feed omnidirectional antenna comprises a dielectric layer and a grounding layer located below the dielectric layer, a radiation metal layer is arranged on the upper surface of the dielectric layer, and a power distribution network structure is etched on the lower surface of the grounding layer; the power distribution network structure adopts a one-equal-to-four type power distribution network; the radiation metal layer is of a metal through hole loading type structure and comprises a metal layer and a plurality of metal through holes formed in the metal layer; the metal through hole is used for connecting the metal layer and the grounding layer; the radiation metal layer is further provided with four metal probes, the positions of the four metal probes correspond to four output ports of the one-equal-division four-type power distribution network, and each metal probe is connected with one output port. The structure of the antenna has a good omnidirectional radiation characteristic, and the technical problems that an existing omnidirectional antenna is large in size structure, low in gain value, high in profile and the like can be solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless communication, and particularly relates to a quasi-TM 11 mode low-profile four-feed omnidirectional antenna. Background Art

[0002] Omnidirectional antennas can transmit / receive electromagnetic wave information / energy in all directions and have important applications, especially in fields such as WLAN communication and wireless positioning. However, currently, omnidirectional antennas are mainly implemented using antennas such as monopole antennas, which have omnidirectional characteristics, usually have a relatively high profile, and are not very conducive to the integration of antenna structures and requirements such as low profile.

[0003] Omnidirectional antennas adopt higher-order modes of microstrip patch structures, such as TM 21 and TM 22 modes. However, when using this method to achieve omnidirectional characteristics, the structural size of the antenna is relatively large, which is not very conducive to the miniaturization of the antenna. Another implementation method is to use an array antenna structure form, using a conventional antenna as the unit structure, rotating the unit structure and forming an array structure. This method achieves the performance of a high gain value. However, currently, this method has a large structural size and is not very conducive to the integration of the antenna with other circuits. Therefore, it is of great research significance to study and design an omnidirectional antenna with high gain and low profile. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a quasi-TM 11 mode low-profile four-feed omnidirectional antenna to solve the technical problems of large size, low gain value, and high profile existing in existing omnidirectional antennas.

[0005] The purpose of the present invention is achieved through the following technical solutions: A quasi-TM 11 mode low-profile four-feed omnidirectional antenna includes a dielectric layer and a ground layer located below the dielectric layer. A radiation metal layer is provided on the upper surface of the dielectric layer, and a power distribution network structure is etched on the lower surface of the ground layer; the power distribution network structure adopts a 1-equal-4 type power distribution network;

[0006] The radiation metal layer is a metal via-loaded structure, including a metal layer and a plurality of metal vias provided on the metal layer; the metal vias are used to connect the metal layer and the upper surface of the ground layer;

[0007] Four metal probes are further provided on the radiation metal layer, and the positions of the four metal probes correspond to the four output ports of the 1-equal-4 type power distribution network. Each metal probe is connected to an output port of the 1-equal-4 type power distribution network.

[0008] The dielectric layer adopts air dielectric with a thickness of 3 mm.

[0009] Compared with the prior art, the present invention has the following beneficial effects: The antenna of the present invention is a metal probe-loaded microstrip structure. Compared with a conventional microstrip patch antenna, the metal via-loaded antenna structure has a higher gain value. At the same time, the quasi-TM 11 mode of its antenna is used to achieve an omnidirectional radiation pattern; a parallel-fed 1-equal-4 power divider network is studied and designed, and a four-fed low-profile high-gain omnidirectional antenna is designed and implemented. The present invention has the characteristics of simple structure, low profile, and high gain, and has good application prospects.

[0010] The present invention well solves the problems existing in current omnidirectional antennas, such as high profile and low gain value. At the same time, a four-fed structure is adopted to achieve a lower circularity, and its antenna has great practical significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is the 3D structure diagram of the antenna of the present invention;

[0012] Figure 2 is the structure of the power divider feed network layer of the antenna;

[0013] Figure 3 is the surface current distribution diagram of the antenna structure;

[0014] Figure 4 is the S11 curve diagram of the antenna;

[0015] Figure 5 is the radiation pattern in the xoz plane of the antenna at the operating frequency point of 2.45 GHz;

[0016] Figure 6 is the radiation pattern in the yoz plane of the antenna at the operating frequency point of 2.45 GHz. DETAILED DESCRIPTION OF THE INVENTION

[0017] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0018] As Figure 1 shown, a quasi-TM 11 mode low-profile four-fed omnidirectional antenna of the present invention includes a dielectric layer 2 and a ground layer 4 located below the dielectric layer 2. A radiation metal layer 1 is provided on the upper surface of the dielectric layer, and a power distribution network structure 5 is etched on the lower surface of the ground layer 4; the power distribution network structure 5 adopts a 1-equal-4 power distribution network, and its structure is as Figure 2 shown. The 1-equal-4 power distribution network is produced by PCB processing technology, and its processing and assembly are simple, suitable for fields such as wireless communication, wireless energy transmission / collection, etc.;

[0019] The radiation metal layer 1 has a metal via-loaded structure, including a metal layer and a plurality of metal vias 6 provided on the metal layer; the metal vias 6 are used to connect the metal layer and the upper surface 3 of the ground layer; in this embodiment, the metal layer adopts a square structure, and four metal vias 6 are provided on the metal layer. The four metal vias are evenly and symmetrically distributed on two diagonal lines of the metal layer, forming a quasi-TM 11 mode antenna.

[0020] Four metal probes 7 are also provided on the radiation metal layer 1. The positions of the four metal probes 7 correspond to the four output ports of the 1-way 4-way power distribution network. Each metal probe 7 is connected to an output port of the 1-way 4-way power distribution network, realizing a four-feed antenna structure. By using the 1-way 4-way power distribution network, each output of the feed network has equal-amplitude and in-phase characteristics, and can achieve a lower circularity of the antenna.

[0021] The dielectric layer 2 uses air as the dielectric, with a thickness of 3 mm, so as to improve the gain value of the antenna and broaden the working bandwidth of the antenna.

[0022] The current on the surface of the antenna structure of the present invention (i.e., the upper surface of the radiation metal layer 1) is as Figure 3 shown. From the current distribution characteristics in the figure, it can be seen that when the amplitudes of each excitation port are equal and in the same phase, the current shows a centrosymmetric relationship, so that the antenna of the present invention has an omnidirectional radiation characteristic.

[0023] The S11 curve of the antenna of the present invention is as Figure 4 shown. From Figure 4 it can be seen that the antenna of the present invention has good working characteristics at the working frequency point of 2.45 GHz, meeting the basic requirements of the antenna.

[0024] Figure 5 is the radiation pattern of the antenna in the xoz plane at the working frequency point of 2.45 GHz. Figure 6 is the radiation pattern of the antenna in the yoz plane at the working frequency point of 2.45 GHz.

[0025] Those of ordinary skill in the art will realize that the embodiments described here are to help readers understand the principles of the present invention, and it should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those of ordinary skill in the art can make various other specific deformations and combinations without departing from the essence of the present invention based on the technical revelations disclosed in the present invention, and these deformations and combinations are still within the protection scope of the present invention.

Claims

1. A quasi-TM based 11 A low profile quad-fed omnidirectional antenna, characterized in that: It comprises a dielectric layer (2) and a grounding layer (4) located below the dielectric layer (2); a radiation metal layer (1) is provided on the upper surface of the dielectric layer; and a power distribution network structure (5) is etched on the lower surface of the grounding layer (4); the power distribution network structure (5) adopts a 1-equally divided 4-type power distribution network; The radiation metal layer (1) is a metal through-hole loaded structure, comprising a metal layer and a plurality of metal through-holes (6) arranged on the metal layer; the metal through-holes (6) are used to connect the metal layer and the upper surface (3) of the ground layer; Four metal probes (7) are also provided on the radiation metal layer (1), and the positions of the four metal probes (7) correspond to the four output ports of the 1-equally divided 4-type power distribution network, and each metal probe (7) is connected to an output port of the 1-equally divided 4-type power distribution network.

2. A method based on quasi-TM according to claim 1 11 A low profile quad-fed omnidirectional antenna, characterized in that: The medium layer (2) is air medium and has a thickness of 3 mm.

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