Monopole antenna

Abstract

The invention discloses a monopole antenna. The monopole antenna comprises a radiation unit, a circular substrate and a feed coaxial line. The radiation unit comprises four radiation plates which have completely structures and sizes; the radiation plates are in right-angle trapezoidal-shaped, the right-angle waists of the radiation plates are provided with rectangular grooves; the long edges of the grooves are parallel to the upper bottom edges of the radiation plates, the short edges of the grooves are vertical to the upper bottom edges of the radiation plates, the four radiation plates are disposed above a substrate, the lower bottom edges of the four radiation plates are drawn closer to enable the right-angle waists to form cross shapes, the lower bottom edges of the radiation plates are vertical to the substrate, the center of the substrate is provided with an installation hole, the acute angle positions of the four radiation plates go into the installation hole, and the feed coaxial line is fixed in the installation hole and is welded at the summits of the acute angle positions of the four radiation plates; and a circular cover plate is arranged above the four radiation plates, and the cover plate covers the four radiation plates and is fixedly connected with the right-angle waists of the four radiation plates. The monopole antenna has the advantage of realizing omnidirectional radiativity.

Description

technical field [0001] The invention relates to an antenna technology; in particular, it relates to a monopole antenna. Background technique [0002] With the rapid development of science and technology, people's lives are becoming more and more modernized, and limited frequency resources are becoming more and more tense. People have put forward higher requirements for the capacity and transmission rate of wireless communication, whether in military communication or civilian communication systems. It not only requires high-quality transmission of voice, text, image and other information, but also requires broadband, miniaturization and sharing of equipment. As a device for transmitting and receiving electromagnetic waves, the antenna is an important part of the wireless communication system. The performance of the antenna directly determines the quality of the wireless communication system. In the modern military communication system, frequency hopping and spread spectrum t...

AI Technical Summary

Problems solved by technology

[0003] However, in the high frequency band, the finite height unloaded monopole antenna currently used in most cases

However, because the input impedance of the finite height unloaded monopole antenna changes drastically with the resonant frequency, and it is difficult to match the 50 ohm feed coaxial line, resulting in a narrow bandwidth and a large profile, it is difficult to achieve omnidirectional radiation

For example, the commonly used RLC monopole antenna, although the RLC monopole antenna can achieve a wider bandwidth, but its electrical length can reach one-sixth of the wavelength, which is not conducive to realizing the low profile of the antenna

Although the equivalent monopole antenna has a small electrical length, its radiation has strong directivity, and it is difficult to achieve omnidirectional radiation.

Under the current technical conditions, to cover the entire communication frequency band and achieve omnidirectional radiation, several antennas are generally required to work at the same time. However, due to the mutual coupling effect between the antennas, the performance of the entire antenna system is greatly reduced.

Images