In bi-directional relaying networks two sources A and B intend to exchange messages with each other with the help of intermediate relaying nodes. In order to achieve higher spectral efficiency compared to the conventional orthogonal transmissions using 4 time slots, analog network coding (ANC) can be adopted at the relay R, which aims to yield a superimposed message with simple weighting and amplification of the received signals that is further broadcasted back to the sources. Since such a joint message contains information of both sources, A(B) is able to extract its wanted part from B(A) by removing the self-interference, which is a priori to A(B).

This work strats with a literature search in the field of ANC, and should cover a quick investigation of the theorectical capacity region, transmission protocols of bi-directional communications and filter design at the relay which is especially important for multiple-antenna relays. The sum rate for the ANC based two-way relaying network is analyzed and optimized for evaluation of the overall system performance.

For successful accomplishment of this work, adequate knowledge from CT I+II and ATDC is preferred.