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arXiv · 1106.2464

On the Sum Capacity of K-user Cascade Gaussian Z-Interference Channel

Yuanpeng Liu·Elza Erkip
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Abstract

A $K$-user cascade Gaussian Z-interference channel is a subclass of the general $K$-user Gaussian interference channel, where each user, except the first one, experiences interference only from the previous user. Under simple Han-Kobayashi schemes assuming Gaussian inputs and no time sharing, it is shown that the maximum sum rate is achieved by each user transmitting either common or private signals. For K=3, channel conditions under which the achieved sum rate is either equal to or within 0.5 bits to the sum capacity are identified.

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Yuanpeng Liu, Elza Erkip. 2011-06-13. On the Sum Capacity of K-user Cascade Gaussian Z-Interference Channel. https://arxiv.org/abs/1106.2464

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