Analysis of Bent Wire Antenna Resonant Frequency for Different Bent Angles. Issue 12 (7th December 2019)

• Record Type: Journal Article
• Authors: Suganya, J.; Sciacca, Umberto; Baskaradas, James A.; Zirizzotti, Achille
• Is Part Of: Radio science. Volume 54:Issue 12(2019)
• Page Start: 1240
• Page End: 1251
• Publication Date: 2019-12-07
• Subjects: GPR Antenna -- Equivalent Circuit -- Radio Glaciology -- Electrically Small Antenna; Radio meteorology -- Periodicals; Radio wave propagation -- Periodicals; 621.38405
• DOI: 10.1029/2019RS006906
• Languages: English
• ISSNs: 0048-6604

Abstract

Abstract: For the bedrock survey in the temperate glacier regions, low frequency antenna system of the airborne ground penetrating RADAR plays a very important role. A small size antenna, working at 10 MHz, would make its use easier in various radar applications. Reducing the resonant frequency of the wire dipole antenna structure, without increasing the physical size, can be attained by introducing bents in the existing structure. This paper introduces a new bent wire dipole antenna and presents the effects of bent angle of 80 °, 70 °, 60 °, 50 °, 45 ° and 40 ° of the wire antenna on the antenna parameters such as resonant frequency, S11, VSWR, gain and radiation pattern. A broadband four element equivalent circuit model of a straight dipole is used with some modifications in the R, L, C equations for the new bent wire dipole antenna by utilizing the bent angle. The frequency response of the equivalent circuit model, calculated resonant frequency values using the equations and the simulated results of the bent wire dipole antenna is compared and analyzed. As the antenna placement area inside the anechoic chamber is limited, the size of the 10MHz antenna has been scaled down by a factor of 0.01. This modifies the resonant frequency of the new structure to 1GHz. The scaled down antenna system are simulated, analyzed and tested in a GTEM cell. For bandwidth improvement of the 10 MHz antenna, a lumped element matching circuit has been designed and simulated. Key Points: 10 MHz bent wire antenna for airborne Geo RADAR application is proposed along with the analysis of the effect of dipole armbend angles Modified lumped element equations of the four element equivalent circuit for the 10 MHz antenna and testing of 1 GHz scale down antenna Bandwidth improvement of the 10 MHz antenna using a lumped element matching circuit have been simulated