This paper is motivated by a sensor network on a correlated field where
nearby sensors share information, and can thus assist rather than interfere
with one another. We consider a special class of two-user Gaussian interference
channels (IFCs) where one of the two transmitters knows both the messages to be
conveyed to the two receivers. Both achievability and converse arguments are
provided for a channel with Gaussian inputs and Gaussian noise when the
interference is weaker than the direct link (a so called weak IFC). In general,
this region serves as an outer bound on the capacity of weak IFCs with no
shared knowledge between transmitters.Comment: This paper appears in CISS 2006, Princeton, N