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arXiv · 1109.4314

On the Degrees of Freedom of $K$-User SISO Interference and X Channels with Delayed CSIT

Mohammad Javad Abdoli·Akbar Ghasemi·Amir Keyvan Khandani
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Abstract

The $K$-user single-input single-output (SISO) AWGN interference channel and $2\times K$ SISO AWGN X channel are considered where the transmitters have the delayed channel state information (CSI) through noiseless feedback links. Multi-phase transmission schemes are proposed for both channels which possess novel ingredients, namely, multi-phase partial interference nulling, distributed interference management via user scheduling, and distributed higher-order symbol generation. The achieved degrees of freedom (DoF) values are greater than the best previously known DoFs for both channels with delayed CSI at transmitters.

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Mohammad Javad Abdoli, Akbar Ghasemi, Amir Keyvan Khandani. 2011-09-20. On the Degrees of Freedom of $K$-User SISO Interference and X Channels with Delayed CSIT. https://doi.org/10.1109/tit.2013.2268154

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