On the design of large bandwidth arrays of slot elements with wide scan angle capabilities
Abstract (Summary)Many phased array applications employ wire antennas above a ground plane, yet at elevation angles close to the ground plane the element pattern is not omni directional in the E-Plane. This characteristic is undesirable for wide scan angles (approaching 70°). In this document, slot arrays are studied, taking advantage of the more desirable element pattern. The wire and slot elements are simulated in an infinite periodic array using the Periodic Moment Method (PMM). The antenna impedance and admittance properties are presented using Smith charts.In order to achieve large bandwidths, closely spaced elements over a ground plane are used. To achieve stable impedance properties over a large range of scan angles, multiple dielectric layers are used. The design process will be thoroughly examined, showing the effect each aspect of the design has on impedance properties of both wire and slot arrays. Three different design examples for slot arrays will be introduced. They each use different element sizes that have advantages and disadvantages in terms of practicality and accuracy of the numeric method used for the impedance calculations. All three of these designs are the result of parametric studies to find the optimum impedance properties over the desired frequency and scan angle range.
School:The Ohio State University
School Location:USA - Ohio
Source Type:Master's Thesis
Date of Publication:01/01/2006