Performance Analysis of Precoding MIMO systems using Lattice Reduction Scheme

Abstract

Lattice reduction (LR) scheme makes the channel matrix close to mutually orthogonal. Depending on the state of the channel matrix, noise power is amplified by the process of signal detection in the precoding systems. When channel state information is available at the transmitter, noise amplification can be reduced in the precoding systems by using LR scheme. In this thesis, we obtain a near orthogonal channel matrix by Lenstra, Lenstra, and Lovasz(LLL) algorithm which is the most popular algorithm of the several algorithms used in LR scheme. We apply the dual basis channel matrix in the LLL algorithm process and analyze the performance between original LR precoding system and dual basis LR precoding system. Through the use of the dual basis channel matrix in the LLL algorithm, the BER performances are improved compared to the original channel matrix.