Hybrid Perturbations in Stacked Patch–Ring Circularly Polarized Microstrip Antennas for CubeSat Applications

Abstract

A hybrid perturbation scheme is used in this paper to achieve wide axial ratio (AR) bandwidth and beamwidth from circularly polarized (CP) microstrip patch-ring antennas using a single probe feed. Perturbations in the diagonal corners of a square ring and a square patch arranged in a stacked configuration are introduced to achieve the circular polarization. First, an enhanced axial ratio bandwidth is obtained when a combination of a square ring and a square patch with negative perturbations is used as parasitic and driven elements respectively. Next, circular polarization with wider axial ratio bandwidth, wider beamwidth, and lower cross-polarization is obtained when a combination of a driven square patch with positive perturbation and a parasitic square ring with negative perturbation, termed as hybrid perturbations, is used. This antenna has a footprint suitable for small satellite applications (e.g. CubeSats) and its operating frequencies cover the allocated S-band downlink frequencies of NASA Deep Space Network (DSN) and NASA Near Earth Network (NEN).

Multi-slot Antennas Excited by Novel Dual-stub Loaded Microstrip Lines for 4G/5G Bands

“…Two open and wide slots are used at the lengthwise edges of the ground plane and excited by a 50-Ω printed feed line. This technique excites and exploits a set of modes that merge respective resonances to maintain stable matching over a wideband of frequencies [18][19][20][21][22]. A new class of double circular stubs loaded feed line is introduced to shoot up the electromagnetic coupling from the feed line to multiple slots improving the overall bandwidth.…”