Research On Miniaturized Wideband Antenna And Phased Array

In order to adapt to the multi-channel and muti-functional characteristics of themodern satellite, wireless communication and radar systems, more and more requests ofthe performance of the broadband antenna are put forward. In these areas, thebroadband phased array antenna plays a prominent role. The Vivaldi ante nna is chosenas the array element due to its excellent performance. Its structure can be divided intotwo parts: the feeding part and the gradient curve radia tion structure. The broadbandmicrostrip-to-slotline structure is adopted to feed the antenna.As the antenna array has a higher requirement for the element, especially for thebroadband antenna, the size of the antenna element must be small enough for the sake ofinhibiting the appearance of the grating lobe. This paper proposes two kinds of Vivaldiantennas. One type is the Vivaldi fed by microstrip-to-slotline balun loaded withrectangular aperture corrugated structure, the other is the antipodal Vivaldi fed bymicrostrip with corrugated structure. By loading the corrugated structure, the effecitivepath of the surface current is increased to achieve miniaturization. In the end, a Vivaldiantenna with a novel curve type is designed, whose width is14mm (0.36times of thewavelength at the lowest frequency), operating from7.7to18.9GHz. In the design ofantipodal Vivaldi antenna, two kinds of regular slot edge (RSE) structures are employed.The transversal slot edges help to extend the low-end operating frequency and improvethe radiation characteristics, while the longitudinal ones have the potential to inhibit theback lobe, contributing to the enhancement of antenna gain.It can work between7.7and20.0GHz with a width of just11mm (0.29times of the wavelength at the lowestfrequency).Based on the antenna element, a wideband1×5E-plane Vivaldi antenna array isdesigned with a total gain of10.9-13.7dBi. This array is able to work from8to12GHzand scan angle up to22°, while this array can scan up to34°in the H-plane. In order tolower the side-lobe level, the magnitude of energy distribution is based on Taylorfunction when all the elements in the array are fully excited. Finally, two-dimensionalarray is designed, which can realize two-dimensional scanning by controlling the phase.This article provides new methods in the field of ultra-wideband antennaminiaturization and two-dimensional scanning array.