A Network Coding Approach to Non-Regenerative Multi-Antenna Multi-Group Multi-Way Relaying

A multi-group multi-way relaying scenario is considered. Each node has to transmit an individual message and has to receive the messages of all other nodes within its group. These multi-way communications between the multi-antenna nodes are performed via an intermediate non-regenerative multi-antenna relay station. Self- as well as known-interference cancellation are exploited at the nodes and are considered for the derivation of the relay transceive filter. Furthermore, to achieve high spectral efficiency, a transmit strategy which exploits the ideas of network coding is proposed. The proposed transmit strategy combined with the derived relay transceive filter requires less antennas at the relay station and achieves higher sum rates compared to conventional approaches which do not fully exploit the interference cancellation capabilities of the nodes.