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Abstract: Costas arrays have ideal autocorrelation and are widely used in radar, sonar and other fields. Two main methods to obtain Costas arrays are algebraic construction and exhaustive search, the ...

Abstract: The search for low-altitude targets becomes a more challenging task for airborne phased array radar, due to the limited system resources and serious ground clutter. In this article, an ...

Matteo Paz built a machine-learning program that could spot faint and changing light signals in space. What began as a summer learning project has turned into a scientific discovery. An American high ...