Phased array technology has been evolving steadily with advances in solid state microwave integrated circuits, analysis and design tools, and reliable fabrication practices. With significant government investments, the technologies have matured to a point where phased arrays are widely used in military systems. Next generation phased arrays will employ high levels of digitization, which enables a wide range of improvements in capability and performance. These digital arrays will leverage the rapid commercial evolution of digital processor technology and high speed logic. This paper will describe the evolution of phased arrays from passive to active to digital architectures, and highlight the critical technologies that enable them. It will also be shown that dramatic cost reductions in phased arrays are possible by employing high-volume commercial microwave manufacturing and packaging techniques to a tile array architecture, which greatly reduces the quantity of printed circuit board material, RF connectors, and cables in the array. A simple phased array cost model will be described which compares the cost of traditional slat arrays with the lower cost tile array approach.
