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arXiv · 2106.13507

Pilot Contamination Elimination for Channel Estimation with Complete Knowledge of Large-Scale Fading in Downlink Massive MIMO Systems

Qazwan Abdullah·Norsaliza Abdullah·Adeb Salh·Lukman Audah·Nabil Farah·Abbas Ugurenver·Abdu Saif
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Abstract

Massive multiple-input multiple-output is a very important technology for future fifth-generation systems. However, massive massive multiple input multiple output systems are still limited because of pilot contamination, impacting the data rate due to the non-orthogonality of pilot sequences transmitted by users in the same cell to the neighboring cells. We propose a channel estimation with complete knowledge of large-scale fading by using an orthogonal pilot reuse sequence to eliminate PC in edge users with poor channel quality based on the estimation of large-scale fading and performance analysis of maximum ratio transmission and zero forcing precoding methods. We derived the lower bounds on the achievable downlink DR and signal-to-interference noise ratio based on assigning PRS to a user grouping that mitigated this problem when the number of antenna elements approaches infinity The simulation results showed that a high DR can be achieved due to better channel estimation and reduced performance loss

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Qazwan Abdullah, Norsaliza Abdullah, Adeb Salh, Lukman Audah, Nabil Farah, Abbas Ugurenver, Abdu Saif. 2021-06-25. Pilot Contamination Elimination for Channel Estimation with Complete Knowledge of Large-Scale Fading in Downlink Massive MIMO Systems. https://arxiv.org/abs/2106.13507

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