  The interference channel with degraded message sets (IC-DMS) refers to a
communication model in which two senders attempt to communicate with their
respective receivers simultaneously through a common medium, and one of the
senders has complete and a priori (non-causal) knowledge about the message
being transmitted by the other. A coding scheme that collectively has
advantages of cooperative coding, collaborative coding, and dirty paper coding,
is developed for such a channel. With resorting to this coding scheme,
achievable rate regions of the IC-DMS in both discrete memoryless and Gaussian
cases are derived, which, in general, include several previously known rate
regions. Numerical examples for the Gaussian case demonstrate that in the
high-interference-gain regime, the derived achievable rate regions offer
considerable improvements over these existing results.
