Geometry-Based Modeling of Self-Interference Channels for Outdoor Scenarios

In-band full-duplex (IBFD) transmission has the potential to nearly double the throughput by improving the spectral efficiency. To achieve this, the self-interference (SI) at the receiver due to one’s own transmission must be suppressed, such that it does not obscure the desired signal. Compact on-frequency repeaters are suitable candidates for initial implementation of IBFD. However, the design, evaluation and optimisation of such systems requires realistic SI channel models. In this contribution, we characterize measured multiple-input multiple-output (MIMO) SI channels as a two-dimensional site-specific geometrybased stochastic channel model (GSCM). The model includes smooth walls causing specular reflections, diffuse scatterers along the smooth walls, and mobile scatterers modelling pedestrians and vehicles. Importantly, the model provides delay, angular and polarimetric characteristics of the MIMO SI channels, and is validated by comparing the measured and simulated channels in delay, Doppler and spatial domains.