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Research Article |

Innovative Approach of Spectral Efficiency Optimization over Various Pilot Reuse Factors

Author(s): Nirav Patel* and Vijay Patel

Published In : International Journal of Electrical and Electronics Research (IJEER)        Volume 11, Issue 4

Publisher : FOREX Publication

Published : 07 November 2023

e-ISSN : 2347-470X

Page(s) : 1001-1012

DOI: https://doi.org/10.37391/ijeer.110418

Abstract

The Massive MIMO with TDD is breakthrough technology for spectral efficiency gains. The CSI is essential for spectral efficiency gains and CSI can be obtained by channel estimation methods. The channel estimation methods employ known pilot s sequences to estimate the channel before actual data transmission. However, the channel coherence is time and frequency limited, which reflects the trade-off between the resources available for pilots and those available for data in coherent block for transmission. The pilot sequences reuse in other cells can reduce pilot overhead, called pilot reuse. However potential interference is introduced, by pilot reuse, in the channel estimation phase, called pilot contamination. The aim is to determine optimum pilot reuse factor for better SE using low computational complexity estimation method. The sum averaged SE has been obtained for pilot reuse factor 1, 2, 4, 8 and 16 using MMSE, EW-MMSE and LS channel estimation methods. The obtained results reveals that the difference between values of SEs for f=1 to f=2 to f=4 is very low and performance difference between estimators decreases as pilot reuse factor increases, which allows to use LS estimator to get performance almost equal to MMSE with less computational complexity. Also, the pilot reuse factor f=4 found optimum among all for given constraint.

Keywords: Massive MIMO, Spectral Efficiency, Channel Estimation, Pilot Reuse Factor, Inter-cell Interference, MMSE, EW-MMSE and LS.




Nirav Patel*, Research Scholar, Ganpat University; Email: nirav2009ec@gmail.com

Vijay Patel, Assistant Scholar Ganpat University; Email: vijay.patel@ganpatuniversity.ac.in

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Nirav Patel and Vijay Patel (2023), Innovative Approach of Spectral Efficiency Optimization over Various Pilot Reuse Factors. IJEER 11(4), 1001-1012. DOI: 10.37391/ijeer.110418.