Johns Hopkins University

Robert S Duggan

Timothy A Sleasman

David B Shrekenhamer

Ra'id S Awadallah

Charles E Quintero

A system can include a plurality of satellites synchronized in a Waves constellation tailored to maximize coverage of a target ground location at one or more predetermined latitudes with a minimal number of satellites. The plurality of satellites can orbit the Earth in a plurality of orbital planes evenly spaced in right ascension of ascending node. The plurality of satellites can be evenly spaced in true anomaly within each orbital plane. The Waves constellation can phase the plurality of orbital planes, such that satellites in neighboring orbital planes simultaneously cross the Equator together with synchronized true anomaly positions, all in ascending or descending motion, thereby forming a wave of satellites in all orbital planes that rise and fall together.

Latitude optimized satellite constellation

A metasurface device in the form of a unit cell may include a first metasurface sub-cell configured to exhibit a first resonant electromagnetic field (EMF) response and a second metasurface sub-cell configured to exhibit a second resonant EMF response. Each the two metasurface sub-cells may include a patterned layer and a variable impedance element operably coupled to the patterned layer. The variable impedance element may be configured to, in response to receipt of a control signal, change an impedance of the respective metasurface sub-cell based on the control signal to change the EMF response of the sub-cell. The first metasurface sub-cell and the second metasurface sub-cell may be disposed in a cascaded configuration such that first EMF response and the second EMF response couple to exhibit an integrated EMF response for the metasurface unit cell.

Growing community of inventors

Bethesda, MD, United States of America

Robert S Duggan