In-Band Full-Duplex Operation in High-Speed Mobile Environments: Not So Fast!

In-band full-duplex (IBFD) technology is promised to deliver us from the scarcity of spectral resources as well as create novel multifunction wireless systems [1]. This concept was initially investigated in the 1960s for continuous-wave radar applications [2], and, in the past decade, it has undergone a shift in research toward communications [3]–[7] and converged RF systems [8], [9]. Since 2010, more than 600 IEEE publications alone have focused on at least one aspect of the technology, including more than 400 conference papers, 200 journal articles, and 20 magazine features [10]. After digesting these numbers, it is fair to ask: Why has IBFD functionality not been incorporated into a wireless standard yet?