Information Flows at the Deep Physical Layer Level

The objective of this chapter is a description of the wireless communication process from a physical point of view. The analysis of the communication system is carried out considering an extended version of the OSI stack that includes an additional layer placed below the Physical Layer (PL). In this further layer, called the Deep Physical Layer (DPL), the communication process is analyzed in terms of distinguishable electromagnetic field configurations on the receiving antenna. The DPL contains all the resources potentially available to the telecommunication system in terms of space/time/polarization field configurations, while the PL implements specific solutions to exploit the potential offered by the DPL. Such a potential is limited only by the physical laws, which are inviolable. Consequently, the limits imposed at the level of DPL are absolute. In this sense, the DPL is a more fundamental level than the PL. The numerous solutions proposed for 6G that include intelligent modifications of the propagation environment can be seen as “data processing” at the DPL level in order to preserve information lost in previous generations of communication systems.