Diversity analysis of two-way MIMO relaying system based on zero-forcing

The two-way multiple-input and multiple-output relay system is investigated in this paper, where bi-directional communications between two source nodes are supported by a relay node with multiple antennas. The achievable diversity order of the three-phase two-way relaying protocol based on zero-forcing is derived. It is found in this paper that the upper bound of the diversity order is related to the number of antennas at the relay node and the number of data streams. Numerical and simulation results are presented to validate theoretical analysis.