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arXiv · 2001.06554

PARAFAC-Based Channel Estimation for Intelligent Reflective Surface Assisted MIMO System

Gilderlan T. de Araújo·André L. F. de Almeida
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Abstract

Intelligent reflective surface (IRS) is an emergent technology for future wireless communications. It consists of a large 2D array of passive scattering elements that control the electromagnetic properties of radio-frequency waves so that the reflected signals add coherently at the intended receiver or destructively to reduce co-channel interference. The promised gains of IRS-assisted communications depend on the accuracy of the channel state information. In this paper, we propose two novel channel estimation methods for an IRS-assisted multiple-input multiple-output (MIMO) communication system. Assuming a structured time-domain pattern of pilots and IRS phase shifts, we show that the received signal follows a parallel factor (PARAFAC) tensor model that can be exploited to estimate the involved communication channels in closed-form or iteratively. Numerical results corroborate the effectiveness of the proposed channel estimation methods and highlight the involved tradeoffs.

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Gilderlan T. de Araújo, André L. F. de Almeida. 2020-01-17. PARAFAC-Based Channel Estimation for Intelligent Reflective Surface Assisted MIMO System. https://arxiv.org/abs/2001.06554

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