# Analysis of Reduced Complexity Widely-Linear Adaptive Forgetting-Factor Inverse Square-Root Recursive Least Squares algorithm

## Main Article Content

## Abstract

Based on widely-linear approach, the proposed reduced complexity inverse square-root recursive least squares algorithm is presented with the methods of adaptive forgetting-factor algorithm. The proposed reduced complexity widely-linear approaches based on inverse square-root recursive least squares algorithm is introduced for a relation between widely-linear and reduced complexity mechanism. By using mean square deviation approach, the proposed optimal forgetting-factor mechanism for optimal gain sequence is presented. Adaptive forgetting-factor inverse square-root recursive least squares algorithm is considered with regard to an optimal forgetting-factor algorithm. A reduced-complexity widely-linear inverse square-root recursive least squares algorithm with the adaptive inverse square-root mechanism, called QR-decomposition for single-carrier frequency-domain equalization systems is presented. Simulation results show that the performance of proposed algorithm is shown that similar to widely-linear approach compared with the conventional algorithm.

## Article Details

Copyright @2021 Engineering Transactions

Faculty of Engineering and Technology

Mahanakorn University of Technology

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