Spectral Efficient and Fair User Pairing For Full-Duplex Communication in Cellular Networks

A promising new transmission mode in cellular networks is the three-node full-duplex (FD) mode, which involves a base station with FD capability and two half-duplex user transmissions on the same frequency channel for uplink and downlink. The three-node FD mode can increase spectral efficiency, especially in the low transmit power regime, without requiring FD capability at user devices. However, when a large set of users are scheduled in this mode, self-interference at the base station and user-to-user interference can substantially hinder the potential gains of FD communications. This paper investigates the problem of grouping users to pairs and assigning frequency channels to each pair in a spectral efficient and fair manner. Specifically, the joint problem of user uplink/downlink frequency channel pairing and power allocation is formulated as a mixed integer nonlinear problem that is solved by a novel joint fairness assignment maximization algorithm. Realistic system-level simulations indicate that the spectral efficiency of the users having the lowest spectral efficiency is increased by the proposed algorithm, while a high ratio of connected users in different loads and self-interference levels is maintained.