Enabling broadband, highly integrated phased array radiating elements through additive manufacturing

This paper describes the use of stereolithography (SLA) and other additive manufacturing (AM) techniques to realize novel broadband (>3:1 bandwidth), dual-polarized, wide-scan, phased array radiators on λ/2-grid at S-, X-, Ku- and W-Band. Three new radiator designs are described, which are variants of the widely used notch antenna (also known as the tapered slot antenna (TSA) or Vivaldi antenna) that have been designed to take advantage of the manufacturing flexibility, batch processing capability and precision afforded by AM. The three designs discussed are (1) a planar-fed notch radiator with modular, interconnected (across multiple elements) free-space transformers, (2) a fully-monolithic, fully-interconnected (across multiple elements) notch radiator array containing integrated feeds, baluns and free-space transformers, and (3) a planar-fed notch radiator with direct-to-wafer, batch-printed free-space transformers. The first two designs have the potential to lower cost, weight, and cycle time through reduced assembly part count and hollow/perforated structure, which is not possible or impractical with other manufacturing techniques. The third design allows for previously unrealizable, wideband, highly efficient, on-grid phased array architectures at millimeter-wave (MMW) frequencies (e.g. W-band) and eliminates the need for expensive pick-and-place operations or capital equipment.