Millimeter-wave phased arrays for 5G: An industry view on current issues and challenges

Large antenna arrays have been always exploited for radar applications in order to provide very high spatial resolution, beam-forming and null-steering. These capabilities have been found to be extremely appealing for communication systems too because of their potential to provide highly-directive beams as the best solution to reduce interference and increase the overall capacity, allowing spectral reuse through spatial diversity. Nowadays the big challenge is not only related to the maximization of the overall system performance - which have been proven to be very effective when considering full-phased/full-digital architectures - but is mainly focused on the economic side: the real goal is to keep cost and energy consumption sufficiently low to obtain affordable products. This work focuses on millimeter-wave wireless systems (nun-Waves), and presents an overview of the application scenarios for 5G (and beyond) networks, together with the main related challenges and finally explores some techniques that can be adopted to design energy- and cost-efficient phased array antennas.