Full duplex: Coming into reality in 2020?

Mobile traffic is projected to increase 1000 times from 2010 to 2020. This poses significant challenges on the 5^th generation (5G) wireless communication system design, including network structure, air interface, key transmission schemes, multiple access, and duplexing schemes. In this paper, full duplex (FD) is discussed, aiming to highlight some insights on various issues including deployment scenarios, frame structures, reference signals (RS), interference mitigation, transceiver structures/calibration, and extension of time division duplex (TDD)/frequency division duplex (FDD) to full duplex. It is anticipated that with future standardization and deployment of FD systems, TDD and FDD will be harmoniously integrated, supporting all the existing half duplex mobile phones efficiently, and leading to a much enhanced 5G system performance.