Full-Duplex Cellular Networks

Abstract

Full-duplex (FD) communications with simultaneous transmission and reception on the same carrier have long been deemed a promising way to boost spectrum efficiency, but hindered by the techniques for self-interference cancellation (SIC). Recent breakthroughs in analog and digital signal processing yield the feasibility of over 100 dB SIC capability, and make it possible for FD communications to demonstrate nearly doubled spectrum efficiency for point-to-point links. Now it is time to shift at least partially our focus to FD networking, such as in cellular networks. FD networking has more complicated interference environments. Therefore, its performance improvement is not that straightforward compared with half-duplex networking. Before putting FD networking into practice, we need to understand to which scenarios FD communications should be applied under the current technology maturity, how bad the performance will be if we do nothing to deal with the newly introduced interference, and most importantly, how much improvement could be achieved after applying advanced interference management solutions. We will discuss all these questions in this article. In particular, we will investigate advanced interference management solutions, including power control and user scheduling, and show that up to 91 percent spectrum efficiency gain and 110 percent energy efficiency gain of FD cellular networks over its HD counterpart can be achieved by applying these solutions.