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arXiv · 1605.08552

Degrees of Freedom of $M\times N$ SISO X Channel with Synergistic Alternating CSIT

Young-Sik Moon·Jae-Hong Kim·Gyeonggi-do·Jong-Seon No·Dong-Joon Shin
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Abstract

In this paper, degrees of freedom (DoF) is investigated for the $M\times N$ single input single output (SISO) X channel with alternating channel state information at the transmitters (CSIT). It is known that the sum DoF of 2-user SISO X channel with synergistic alternating CSIT is the same as the sum DoF of 2-user $(M=N=2)$ SISO X channel with perfect CSIT [8]. In this paper, such 2-user X channel schemes are extended to the general $M\times N$ X channel. It is shown that the proposed $M\times N$ X channel schemes with synergistic alternating CSIT achieve $2M/(M+1)$ sum DoF. This DoF with $M=N=K$ is strictly lager than the best known DoF for the $K$-user X channel with delayed CSIT.

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Young-Sik Moon, Jae-Hong Kim, Gyeonggi-do, Jong-Seon No, Dong-Joon Shin. 2016-05-27. Degrees of Freedom of $M\times N$ SISO X Channel with Synergistic Alternating CSIT. https://arxiv.org/abs/1605.08552

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