On Bandwidth Efficient Channel Estimation Algorithms For Hybrid MIMO ACO OFM VLC System

Abstract

The current period is an Electronics and Communication era. From the analogue newlinevoice of 1st Generation (1G) to the existing broadband technology of 4th newlineGeneration (4G) to have a higher data rate and mobility of future 5th (5G) newlinecommunication engineering domain has seen very significant growth. Less power newlineconsumption, high data rate with minimal errors, cost-effective and bandwidthefficient newlinetechniques are the essential points to be considered while designing any newlinemodern communication systems. newlineThe goal of this thesis is to presents the idea of sparse channel estimation newlineusing Compressed Sensing (CS) method for space-time block coding (STBC), newlineand spatially multiplexing (SM) derived hybrid multiple-input multiple-output newline(MIMO) asymmetrically clipped optical-orthogonal frequency division multiplexing newline(ACO-OFDM) for visible light communication (VLC). This hybrid system newlineaccounts multiplexing gain of SM and diversity gain of STBC technique. newlineA central theme throughout the thesis is Compressed Sensing (CS) theory; a newlinebandwidth-efficient technique which is widely used to capture only the necessaryquot newlinedata for various applications and/or data processing. However, reconstruction newlineof the signal using Compressed Sensing algorithm is highly challenging due to newlineunderdetermined systems or sparse nature. newlineIn this process, a new variant of sparsity adaptive matching pursuit (SaMP) newlinealgorithm called dynamic step-size sparsity adaptive matching pursuit (DSSSaMP) newlinealgorithm. It make-use of the inherent and implicit structure of SaMP, newlinealong with dynamic adaptivity of step-size feature which is compatible with the newlineenergy of the input signal, thus the name dynamic step-size. newlineExisting CS-based recovery algorithms like Orthogonal Matching Pursuit (OMP), newlineSaMP, Adaptive step-size Sparsity Adaptive Matching Pursuit (AS-SaMP) and newlineproposed DSS-SaMP were compared for hybrid MIMO-ACO-OFDM Visible Light newlineCommunication (VLC) system, using two methods to solve underdetermined newlinelinear equations i.e. least square (LS) method and minimum mean square error newline