The Approximate Capacity Region of the Symmetric $K$-user Gaussian Interference Channel with Strong Interference
Online Publication Date2016-03-01
Print Publication Date2016-05
Permanent link to this recordhttp://hdl.handle.net/10754/601294
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AbstractThe symmetric K-user interference channel is studied with the goal of characterizing its capacity region in the strong interference regime within a constant gap. The achievable rate region of a scheme combining rate-splitting at the transmitters and interference alignment and successive decoding/computation at the receivers is derived. Next it is shown that this scheme achieves the so-called greedy-max corner points of the capacity region within a constant gap. By combining this result with previous results by Ordentlich et al. on the sum-capacity of the symmetric interference channel, a constant gap characterization of the capacity region for the strong interference regime is obtained. This leads to the first approximate characterization of the capacity region of the symmetric K-user IC. Furthermore, a new scheme that achieves the sum-capacity of the channel in the strong interference regime within a constant gap is also proposed, and the corresponding gap is calculated. The advantage of the new scheme is that it leads to a characterization within a constant gap without leaving an outage set contrary to the scheme by Ordentlich et al..
CitationThe Approximate Capacity Region of the Symmetric $K$-user Gaussian Interference Channel with Strong Interference 2016:1 IEEE Transactions on Information Theory
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