A Full-Duplex Cellular Radio System with Perfect Self-Interference Cancellation

Full-duplex (FD) communication is another topic of great attention in the fifth generation of mobile communications systems since it can improve or even double the spectral efficiency of the conventional half-duplex (HD) method. However, the performance of a FD transceiver is limited by self-interference. Digital active cancellation is one of self-interference cancellation techniques which operates after digitization. Its performance always suffers from the self-interference channel estimation error. In this thesis, a novel digital self-interference cancellation technique without self-interference channel estimation that cancels self-interference completely is proposed. A precoded orthogonal frequency division multiplexing (OFDM) uplink system is employed to increase frequency diversity. Minimum mean square error (MMSE) and maximum likelihood (ML) Viterbi receivers are designed for low traffic and heavy traffic systems, respectively. In both traffic systems, simulation results show that, for the cell-center users, the proposed FD precoded OFDM system outperforms the HD single carrier frequency division multiple access (SC-FDMA) system at a BER of 10^-4 with the same parameters in uplink. Moreover, the peak-to-average power ratio (PAPR) and the computational complexity of the transmitter of the proposed FD precoded OFDM system is lower than that of the HD SC-FDMA system.