Vertically polarized broadband UHF (Ultra High Frequency) waveband antenna

Abstract

The invention discloses a vertically polarized broadband UHF (Ultra High Frequency) waveband antenna. An antenna housing has a hollow cylindrical tubular structure, the upper end of the antenna housing is a sealing face, and the lower end is an opening; a reflecting base plate is a stepped cylinder of which the center is provided with a through hole; an insulating spacer is placed in the through hole; an active array has a U-shaped structure which is integrally formed by bending a rectangular aluminum rod; the two edges of the U-shaped structure are symmetrically distributed, and the top end is an open part; the active array is perpendicular to the upper surface of the reflecting base plate; an inner conductor of a radio frequency connecting piece penetrates through the insulating spacer to be fixedly connected with a mounting through hole on the bottom of the active array; the metal aluminum is made into a cylindrical short-circuit rod to be mounted at through holes on two arms of the active array; and a 50-ohm copper shaft cable is connected with the antenna by the radio frequency connecting piece. In the invention, the antenna meets requirements of vertical polarization and omnidirectional radiation; antenna gain reaches 2dB; 3dB beam width of the antenna is 65 degrees; and the width of frequency band below standing wave 2 is about 20 percent.

Description

technical field [0001] The invention relates to a broadband UHF band antenna. Background technique [0002] At present, the UHF band communication and measurement and control system antennas on general vehicle-mounted, airborne and other portable high-speed mobile platforms are mostly "J"-shaped dipole or disc-cone antennas. The "J" type dipole antenna uses the three-quarter wavelength main element as the basic radiation unit of the antenna, and introduces a quarter-wavelength matching element structure next to the main element to complete the matching between the overall system and the 50-ohm feed. According to the ordinary dipole matching mode, W.B. Freely first proposed the design of the antenna in the article "A Two meter J Antenna" (W.B. Freely, A Two meter J Antenna [J] QST, April, 1977). The "J" type dipole antenna has the characteristics of simple structure and easy tuning, but it often has a narrow operating frequency band (less than 5%). Generally, it works at a p...

AI Technical Summary

Problems solved by technology

[0003] In order to overcome the deficiency that the prior art cannot meet the miniaturized installation requirements of the UHF band communication system antenna on the high-speed mobile platform, the present invention provides a vertically polarized broadband UHF band antenna, by introducing several short circuits on the deformed dipole antenna Strip, with a small current balance reflection chassis (less than half the wavelength) and installation structure to meet the requirements of broadband work in the UHF band

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