Beam Launchers for Secure and Resilient Wireless Communications at Millimeter Waves and Beyond

The security of wireless communications is typically ensured at software level through complex and energyhungry encryption algorithms. The generation of localized beams at millimeter and sub-millimeter waves thus represents a revolutionary-yet challenging-approach to transferring information while ensuring security at the hardware level. This paper presents an overview of recent enabling technologies for generating localized beams at millimeter and sub-millimeter waves, with a focus on the realization of wireless near-field links. Simulations and experiments on several case studies are discussed along with an outlook on promising future directions in the context of wireless power and information transfer.