Co-designed Communication and Sensing

Sixth-generation (6G) wireless systems will offer a multitude of new applica- tions besides connectivity to an unprecedented number of users and devices. It is widely recognized that one of 6G’s most revolutionary innovations will be its ability to enable the localization of non-cooperative objects and, more generally, the sensing of the physical environment via RF signals. This functionality will be a key added value for future mobile radio systems and for which the term perceptive networks has been recently coined. This chapter aims at exploring the main co-design aspects that enable the network to operate both as a communication system and as a radar system for sensing purposes. Then, it presents the main signal processing techniques for object localization, with emphasis on two main modulation techniques: the orthogonal frequency division multiplexing (OFDM) modulation, one of the most successful communication signals, and the orthogonal time frequency space (OTFS) modulation, which is among the candidates for next generation wireless systems. For both waveforms, the chapter focuses on the key aspects that enable radar functionality, highlighting the pros and cons in terms of performance and com- plexity. Finally, an innovative approach that combines both waveforms’ benefits, named dual-domain waveform superposition, is outlined.