Interference, cooperation and connectivity - A degrees of freedom perspective
نویسندگان
چکیده
THIS PAPER IS ELIGIBLE FOR THE STUDENT PAPER AWARD. We explore the interplay between interference, cooperation and connectivity in heterogeneous wireless interference networks. Specifically, we consider a 4-user locallyconnected interference network with pairwise clustered decoding and show that its degrees of freedom (DoF) are bounded above by 12 5 . Interestingly, when compared to the corresponding fully connected setting which is known to have 8 3 DoF, the locally connected network is only missing interference-carrying links, but still has lower DoF, i.e., eliminating these interferencecarrying links reduces the DoF. The 12 5 DoF outer bound is obtained through a novel approach that translates insights from interference alignment over linear vector spaces into corresponding sub-modularity relationships between entropy functions.
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