A Broadband Omnidirectional Antenna

Abstract

A broadband omni-directional antenna comprises a radiating structure, a feed structure and an impedance matching structure. The radiating structure is made of a metal pipe with a solid upper part and a hollow lower part. The feed structure comprises a metal floor board with a central hole and a coaxial cable connector, wherein an outer conductor of the coaxial cable connector is welded to the metal floor board. The impedance matching structure comprises a copper conducting wire, an annular metal sheet and nylon screws, wherein the metal pipe, the copper conducting wire, the annular metal sheet and the floor board are coaxially arranged, an inner conductor of the coaxial cable connector penetrates the central hole of the metal floor board to be connected with the bottom end of the copper conducting wire in a welding mode, the top end of the copper conducting wire is welded to the bottom end of the solid part inside the metal pipe, the bottom end of the metal pipe is welded to the position of an inner circle of the annular metal sheet, and the annular metal sheet is fixed on the metal floor board through the nylon screws. The broadband omni-directional antenna is simple and compact in structure, small in occupied space, and wide in broadband, has horizontal omni-directional radiation characteristics, and can be used for high-power frequency hopping and spread spectrum communication radio stations.

Description

technical field [0001] The invention belongs to the field of communication technology, and further relates to a broadband omnidirectional antenna in the field of electromagnetic field and microwave technology. The invention works in a wide frequency band range, has a horizontal omnidirectional pattern, and is suitable for broadband antennas with wide working frequency bands in modern broadband high-power frequency hopping and spread spectrum communication stations. Background technique [0002] In modern communication technology, in order to ensure the quality of communication and the confidentiality of information, communication stations widely use frequency hopping spread spectrum technology. Therefore, it is required that the antenna must be a broadband antenna with a wide operating frequency band. In addition, due to appearance and space utilization reasons, small size and compact structure have become another requirement restricting the antenna. In the traditional sho...

AI Technical Summary

Problems solved by technology

The shortcomings of the broadband omnidirectional antenna are: although the broadband omnidirectional antenna has a wide impedance bandwidth, the distance between adjacent dipoles is very large, resulting in a large volume of the antenna, which is not suitable for installation in relatively narrow spaces. Limited to shortwave and ultrashortwave applications

However, there are three deficiencies in this method. First, the use of an unbalanced center-fed antenna will cause the radiation pattern of the antenna to be deformed, and the maximum radiation direction is no longer the horizontal direction.

Second, this method connects a passive impedance transformer and a broadband reactive compensation element in series at the position of the feed point. Although theoretically lossless reactive elements are generally used in the impedance matching network, in practice these elements are not Completely lossless, will reduce the radiation efficiency of the antenna

Third, adding a matching network composed of lumped elements at the feed point will make the overall structure of the antenna no longer compact

Therefore, there are relatively large limitations in practical applications.

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