Although monopoles and dipoles theoretically have omnidirectional radiation patterns, in reality, due to the influence of feed lines, the vertical electric field tilts downwards, which affects the radiation characteristics in the horizontal direction, making it difficult to obtain omnidirectional directional patterns. The antenna is composed of dipoles. By properly arranging the isolation between the dipole radiation unit and the feed line, the influence of the feed line is shielded, achieving omnidirectional radiation in the horizontal direction. The antenna uses another dipole as a parasitic unit, allowing the entire antenna to operate in two frequency bands of 0.9GHz and 2.0GHz, with high antenna gain, reaching 10dBi and 12dBi respectively. The entire antenna structure consists of a metal tube in the middle, surrounded by four dielectric plates, each with two dipoles with parasitic units. The dipole length is 137mm, the operating frequency is 0.9GHz, the parasitic unit length is 47mm, and the operating frequency is 2.0GHz. The center distance between the two dipoles on the same substrate is 150mm, and the entire antenna is wrapped in a cylindrical antenna cover with a diameter of 110mm. The feeding part of the antenna uses four power dividers and baluns.

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