Nonreciprocal Phased-Array Antennas

From radio to optical frequencies, phased-array antennas are ubiquitous in modern technology and find wide application in communication and radar systems, imaging, sensing, and radio astronomy, among many other endeavors. These devices provide identical responses in transmission and reception, due to the constraints imposed by time-reversal symmetry. Here, however, the authors present the concept of $n{{0}{0ex}}o{{0}{0ex}}n{{0}{0ex}}r{{0}{0ex}}e{{0}{0ex}}c{{0}{0ex}}i{{0}{0ex}}p{{0}{0ex}}r{{0}{0ex}}o{{0}{0ex}}c{{0}{0ex}}a{{0}{0ex}}l$ phased-array antennas, and demonstrate that such structures significantly extend the functionalities of common arrays by efficiently enabling independent, dynamic control of transmitted and received radiation patterns at the same operating frequency.