Real-time interference reduction for OFDM-based dynamic spectrum access networks

In dynamic spectrum access (DSA) networks, users are allowed to access the available spectrum while keeping neighboring transmissions not interfered. In this demonstration, we show how the available bandwidth can be used efficiently while at the same time keeping the interference power level below a certain threshold. This is done through the use of the constellation expansion technique for orthogonal frequency division multiplexing (OFDM)-based systems in DSA networks. The demonstration is based on real-time implementation of the constellation expansion technique on the reconfigurable Iris 2.0 software defined radio and the universal software radio peripheral (USRP-N210) as the hardware front-end.