Re-thinking Physical Layer Processing. Time for a Change?

In order to support the plethora of the new, pending, transformative use-cases, future wireless systems need to be capable of providing ultra-high-throughput at a network level and of enabling ultra-massive device connectivity that supports ultra-high traffic that is not necessarily human-type but also machine-type. In addition, future wireless systems are required, able to achieve per-link throughputs of the order of Terabits-per-second by exploiting ultra-wide bandwidths. All those when the speed of traditional processors is plateauing, when the transmission environment is transforming (see intelligent reflective surfaces, and extra-large antenna arrays) and when the power consumption is becoming a major challenge. However, while the wireless ecosystem is rapidly evolving, the physical layer processing approaches mainly used in practice, essentially remain the same for more than 20 years. In this context, we discuss how traditional physical layer processing hinders the evolution of wireless systems, and we provide potential directions for substantially improving, if not revolutionizing, future wireless communications.