ADVANCED MIMO CHANNEL ESTIMATION TECHNIQUES: A COMPREHENSIVE REVIEW OF METHODS, ALGORITHMS, AND PERFORMANCE OPTIMIZATION

Samson Eleje; Chidera Anioke; Cosmas Ani

doi:10.4314/njt.v44i1.11

Authors

S. E. Eleje Department of Electronic Engineering, Faculty of Engineering, University of Nigeria Nsukka, Enugu State, Nigeria
C. L. Anioke Department of Electronic Engineering, Faculty of Engineering, University of Nigeria Nsukka, Enugu State, Nigeria
C. I. Ani Department of Electronic Engineering, Faculty of Engineering, University of Nigeria Nsukka, Enugu State, Nigeria

DOI:

https://doi.org/10.4314/njt.v44i1.11

Keywords:

Channel Estimation, MIMO, Fading, Pilot, Antenna

Abstract

The promising characteristic features of Multiple-Input Multiple-Output (MIMO) systems rely on the knowledge of the channel state information (CSI) for coherent signal data detection. The determination of channel state information is achieved using various conventional estimation techniques such as pilot-aided, blind, and semi-blind channel estimation techniques. Obtaining accurate channel state information in MIMO systems is significant tasks upon which system performance depends. This paper presents a comprehensive review of various MIMO channel estimation techniques presented in literature from conventional techniques to more recent deep neural network-based techniques. Various ways of pilot arrangement and complexity reduction techniques are discussed. Furthermore, the key performance indicators in MIMO channel estimation, various algorithms applied in channel estimation and the impact of outdated CSI with its causes are also presented. The recent improvements on the conventional techniques with its impact on the key performance indicators in communication systems such as 5G and beyond Networks, Millimeter-wave Communications, and Massive MIMO system were also reviewed. Accurately estimating wireless channel condition makes signal transmission adaptive leading to optimal performance in transmission and decoding of signals.

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