Dirty paper via a relay with oblivious processing

The Oblivious Relay serves users without a need to know the users error correcting codes. We extend the oblivious relay concept to channels with interference which is known to the transmitter but not to the receiver. Our system uses structured modulation and coding based on lattices. We show that when the interference is known non-causally, it's influence can be overcome wholly and that in simpler causal schemes the performance is usually within the shaping loss of 0.254 bits/channel use from the optimal performance attainable with large lattices.