Advances in the Development of Electronically Scanned Arrays of Balanced Antipodal Vivaldi Antenna

摘要

Last year, significant design improvements to the modular, electrically short, Doubly-mirrored Balanced Antipodal Vivaldi Antenna (DmBAVA) were discussed. Metallic crosswalls and poles were inserted between the adjacent elements. Also, three magnetic slots were strategically placed on the radiator. The new array shows a half decade bandwidth (5:1) of operation. In this paper, further manufacturing and performance enhancing techniques are introduced. The manufacturing enhancing technique is to eliminate the magnetic slots on the outer conductors of the radiator. This increases the real-estate area at the outer conductors to easily insert vias in the substrate. Those vias suppress the H-plane resonance. Radiation patterns of this antenna in a finite array are shown. The performance enhancing techniques are to insert another magnetic slot in the embedded conductor and modify the traditional shape of the flared section of the radiator to improve the impedance match over the desired frequency band. A 16 by infinite array of this antenna was measured in a parallel plate waveguide simulator. The simulated active reflection coefficient shows evidences of over one-half decade bandwidth (6.2:1) operation. The paper also introduces an evolutionary design that exhibits a future research avenue. The Balanced Antipodal Asymmetric Vivaldi Antenna (BA~2VA) resembles basic construction of BAVA except the profiles of the outer conductors are altered. This eliminates the necessity of mirroring and metallic crosswalls for wide scanning applications. A low profile of BA~2VA is modeled to operate over 3:1 bandwidth. The design is being built and will tested soon.