Deployable Tightly Coupled Dipole Arrays For Small Satellites

Abstract

This dissertation presents the theory, design, fabrication, and verification of several critical components for a novel class of origami-based and deployable Tightly Coupled Dipole Arrays (TCDAs) suitable for small satellite applications. This work introduces a new approach to enhance the bandwidth of TCDAs by incorporating a semi-resistive Frequency Selective Surface (FSS) network within the substrate. The integration of this FSS network within a dual-polarized TCDA led to an increased impedance bandwidth of 28:1 from 0.20 GHz to 5.6 GHz. Concurrently, losses above 2.5 GHz are reduced to achieve a radiation efficiency of 83% on average. A major component of the dissertation is devoted to achieving origami folding. As folding is incorporated into the design, it leads to statistical errors on the location of the array elements. To assess the impact of random folding errors, a study is included on the array performance during folding and unfolding. More importantly, several practical realizations for this new class of origami-based TCDAs are presented using a two-layered accordion structure. The latter are fabricated using rigid and flexible substrates. A specific developed design provides operation from 0.4 to 2.4 GHz with VSWR < 3 at broadside and when scanning down to 45° in the E-, D-, and H-planes. Further, an 8×8 prototype is fabricated using a combination of Kapton Polyimide and FR4 and measured to verify the bandwidth and gain. The resulting fabricated design is only 1.1 kg, and its size is reduced by 75% in one dimension when packed This packing compression is made possible by eliminating its vertical Printed Circuit Boards (PCB) and incorporating the balun feeds within the dipole layer. To our knowledge, this is one of the first foldable, low profile, and low-scanning ultra-wideband arrays in the literature.