Joint Transceiver and Power Splitter Design Over Two-Way Relaying   Channel with Lattice Codes and Energy Harvesting
  This letter considers a compute-and-forward two-way relaying channel with simultaneous wireless information and power transfer. Specifically, two single-antenna users exchange information via a multi-antenna relay station based on nested lattice codes. Meanwhile, wireless energies flow from the relay to users for circuit consumption and uplink transmission. Based on this model, an optimization problem is formulated to minimize the transmit power at relay, while guaranteeing the minimal transmission rate at each user. To solve the problem, we propose an efficient iterative algorithm to jointly optimize the transmitter, receiver and power splitter, based on semi-definite relaxation and semi-definite programming. Numerical results of relay transmission powers validate our analysis. 
Zhigang Wen, Shuai Wang, Chunxiao Fan and Weidong Xiang
cs.IT math.IT