Date Added: Dec 2009
In this paper, the authors consider differential modulation in Two-Way Relay Channels (TWRC). In single antenna systems, the authors propose non-coherent schemes for both Amplify- and Forward (AF) and Decode-and-Forward (DF) where the channel state information is not required. These new schemes are counterparts of the traditional non-coherent detection in point to point communications. The difficulty with differential modulation design in TWRC is that the received signal is a mixture of the signals from both source terminals.