Robust Filter Design For Full-Duplex Relay Links Under Limited Dynamic Range

We present a method for joint robust design of linear source and relay filters in a MIMO full-duplex link that supports the transmission of several data streams. The system model accounts for self-interference in the relay, limited dynamic range at the transmit and receive sides of the nodes as well as channel uncertainty. The design criterion is to minimize the worst-case mean square error at the relay input. The resulting nonconvex problem is solved by means of an alternating optimization procedure that decouples source and relay filters at each iteration. Optimization of each individual filter is cast as a semidefinite program. Simulations show the impact of channel uncertainty in the mean square error and how the performance of the proposed method compares to a non-robust design.