QUAD-POLARIZATION WIDEBAND SINUOUS ANTENNA ELEMENTS AND ARRAYS

Abstract

Modern antennas are increasingly being expected to perform multiple functions. The push to having fewer antenna elements, while also covering a larger number of tasks, has led to a huge demand for wideband, multi-function antennas. Sinuous antennas are chosen as the primary focus for this thesis to achieve quad-polarization, wideband performance while attempting to maintain a compact, low-profile shape. Traditional circular-polarization modes are presented together with new techniques for obtaining linear polarization from sinuous antenna elements. The study on sinuous elements is followed by development of (both uniform and variable-sized) phased arrays of these antennas. Connections between array elements are used as a technique to optimize the performance of large, planar arrays of sinuous antennas. Finally, a detailed comparison of the performance of sinuous and spiral antennas is presented to serve as a reference for future designs of such wideband arrays.