In-band full-duplex (IBFD) communications has the potential to nearly double the spectrum efficiency of existing 5G communications. Digital signal processing to mitigate self-interference is one way to realize this full-duplex capability. However, the aggregated wideband nature of 5G coupled with the potential for large delay spreads and short coherence times makes the realistic implementation of such an IBFD processor challenging. In this paper, we address the architectural considerations and describe the practical implementation of a real-time IBFD digital processor and its performance when operating on wideband data collected in a highly dynamic environment.INDEX TERMS Adaptive filters, least mean square methods, radio transceivers, radio communication.