Dissertation > Excellent graduate degree dissertation topics show

Lattice Reduction Aided Precoding Technique for MIMO System

Author: XuXiaoJian
Tutor: JiangLingGe
School: Shanghai Jiaotong University
Course: Communication and Information System
Keywords: MIMO precoding lattice reduction joint precoding vector precoding non-ideal channel model
CLC: TN919.72
Type: Master's thesis
Year: 2008
Downloads: 51
Quote: 0
Read: Download Dissertation

Abstract

MIMO techniques are key schemes for achieving high data rate and performance in 3G mobile communication and beyond generation system. The precoding techniques process the signals at the transmit end, which simplify the complexity of receiver devices, it’s very practical for the downlink of MIMO. Therefore, precoding technique plays an important role in MIMO wireless communication system.As we know, the traditional precoding techniques apply the corresponding detection techniques to the transmit end, which are easily implemented but significantly amplify the noise and deteriorate the performance of MIMO system. Recently, a lot of scholars have introduced the lattice aided technique into the precoding technique to obtain a better CSI matrix and lower the noise amplification, finally achieve great performance gain only at the cost of polynomial complexity. As a result, the lattice reduction aided technique has gained more and more concern for its outstanding performance. A plenty of schemes based lattice reduction aided technique have already been proposed. However, most of the lattice reduction aided schemes were proposed and analyzed under the ideal MIMO model which is assumed by the authors. In fact, channel estimation error and antenna correlation are two of the most important factors which lead to a non-ideal MIMO environment. The LRA precoding scheme which focuses on the non-ideal MIMO model are seldom proposed or analyzed. In this dissertation, concerning the non-ideal MIMO model, several schemes based lattice reduction technique are proposed and analyzed detailed together with the suggestions given for particular real MIMO environment.This dissertation does research on the lattice reduction aided MIMO schemes including linear precoding schemes and non-linear precoding schemes. Based on the ideal MIMO model, the MIMO model in the presence of channel estimation error and antenna correlation channel are built, respectively. Analyze the linear precoding technique including zero-forcing and MMSE schemes, then propose a MMSE based, BLAST technique combined THP scheme. The simulation shows the proposed THP scheme outperforms the other THP schemes under the three models previous built.Concerning the non-ideal MIMO model built in the previous section, a MMSE based, VBLAST technique combined, lattice reduction aided scheme is proposed. The simulation shows the proposed scheme outperforms the zero-forcing based or QR decomposition based schemes. It also achieves good performance under the MIMO model in the presence of channel estimation error and antenna correlation channel.Continue to focus on the non-ideal MIMO model, the deficiency of the proposed the vector precoding scheme is given and a low complexity lattice reduction aided vector precoding scheme based on MMSE and VBLAST technique is proposed .For comparison , a vector precoding scheme based on MMSE and an existing linear processing technique is also proposed. Both the complexity analysis and numerical simulation for the proposed scheme are provided, which shows the scheme proposed in this dissertation a more practical one then the scheme for comparison.

Related Dissertations

CLC: > Industrial Technology > Radio electronics, telecommunications technology > Communicate > Data communication > Divided by the transmission line data communication > Wireless data communications
© 2012 www.DissertationTopic.Net Mobile