Cancelling Adjacent Channel Interference for In-Band Full-Duplex Communications

When operating in the in-band full-duplex (IBFD) mode, wireless in-band distribution link (IDL) is a spectral efficient and cost-effective backhaul technology for Advanced Television Systems Committee (ATSC) 3.0 in a single-frequency network (SFN), since IDL shares the same frequency band allocated for the traditional broadcast services. Therefore, it is desirable to use high-order modulation, e.g., 1024QAM, to achieve a very high data rate for the IDL, such that more bandwidth can be reserved for broadcast service. This presents stringent requirements for the self-interference (SI) cancellation (SIC) at the IDL receiver where the leakage from the co-located transmitter as self-interference seriously corrupts the received signal. Such SI signal is nonlinearly distorted by the high power amplifier (HPA). Moreover, the transmitters broadcast multiple channels at the same time. Therefore, the SI signal also contains leakage from adjacent channels, which is also nonlinear in nature. Accurately cancelling the SI signal with HPA-induced nonlinear distortion and adjacent channel interference (ACI) is considered in this paper. Simulation results demonstrate that under the presence of nonlinear distortion and ACI, linear SIC fails to achieve satisfactory performance, while the previously proposed iterative successive nonlinear SI cancellation (ISNSIC) can effectively cancel the SI with both nonlinear distortion and ACI.