Interference Neutralization for Non-Regenerative Two-Way Relaying Networks—Part II: Optimization

In Part II of this two-part paper, we design optimal relay transmit strategies for a nonregenerative two-way relaying network with multiple repeaters and smart relays with or without interference neutralization (IN). We develop a general framework to optimize different system utility functions, i.e., minimize the required transmit power at the relay subject to minimum SINR constraints, maximize the minimum SINR of the users subject to relay transmit power constraint(s), and maximize the weighed system sum rate subject to relay transmit power constraint(s). Simulation results show that the proposed algorithms outperform the state of art time-division multiplexing (TDM) based algorithm. Compared to the optimal design without applying IN, the IN approach has a reduced computational complexity although it suffers from a small performance loss.