New non-binary TCM and TTCM decoding algorithms for 4G wireless systems

Other Title(s)

خوارزميات جديدة لفك ترميز المرمزات (TCM و TTCM)‎ لأنظمة الجيل الرابع اللاسلكية

Dissertant

al-Hilali, Riyad Ali Abd al-Husayn

Thesis advisor

Thahir, Rad H.
Abd Allah, Abd al-Karim S.

Comitee Members

al-Saffar, Ala A.
Abd al-Jabbar, Jasim M.
Muslih, Mahmud Farhan
al-Sabbagh, Haydar M.
Said, Thamir R.

University

University of Basrah

Faculty

Engineering College

Department

Department of Electrical Engineering

University Country

Iraq

Degree

Ph.D.

Degree Date

2013

English Abstract

This thesis deals with the Multiple Input-Multiple Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) technique that candidates with the fourth generation (4G) of the wireless communication systems.

This technique can provide high data rate transmission without increasing transmit power and expanding bandwidth.

It also can efficiently use space resources and has a bright future.

This thesis presents the channel coding assisted Space-Time Block Code (STBC-OFDM) systems, and employs the Coded Modulation techniques (CM), since the signal bandwidth available for wireless communications is limited.

A new non-binary decoding method is designed and implemented for decoding non-binary convolutional codes, which is independent on the trellis diagram that representing the convolutional encoder.

The 4-state system-based non-binary new decoding algorithm outperforms the 4-state system-based Viterbi algorithm by the gains (8.7 dB and 5.5 dB) at the BERs (10-3 and 10-5) respectively.

This new decoding algorithm outperforms the Viterbi algorithm and other algorithms in its simplicity, since it's decoding procedure depends on logic comparisions between the output and received noisy bits, while the Viterbi algorithm computes the hamming distances and then a comparison between competitive accumulated metrics is done for every state of the trellis diagram.

Also, this new algorithm has small computational complexity that approximately equals to the code word length (T), since it employed a hard-decision method, which needs less computational complexity over the soft-dicision method of Vetirbi algorithm.

The decoding reliability of the new algorithm is suitable for (4G), since the STBC–OFDM concatenated systems-based new algorithm outperforms the binary TCM-based Viterbi algorithm- assisted STBC-OFDM scheme by the gains; (10.93 dB and 19.87 dB) at the BERs (10-3 and 10-5) respectively.

In this new algorithm, errors are decreased with increasing word length, since the sysytem-based novel algorithm has achieved gains (9 dB and 8.3dB) at BER (10-5) for word lenghts (4 k bits and 1M bits) respectively.

Therefore, it is easy to implement the new algorithm with real-time applications.

Furthermore, a non-binary Turbo Trellis Coded Modulation (TTCM) decoder-based multidimensional MAP algorithm-assisted G2 STBC-OFDM is desigend and implemented.

The designed systems deal with non-binary error control coding of the TCM and TTCM-aided STBC-OFDM schemes for transmissions over the Wireless Asynchronous Transfer Mode channel (SWATM) channel.

The idea of non-binary codes has been extended for symbols defined over rings of integers, which outperforms binary codes with only a small increase in decoding complexity.

Also, the thesis employs chaos technique at the decoding stage of the non-binary TTCM decoder, since the turbo decoding algorithm can be viewed as a high-dimensional dynamical nonlinear system.

The ring-TTCM scheme-based chaos technique outperforms the same sysytem based 3-dimensional decoding algorithm by the following gain improvements; (0.51 dB, 0.6 dB, 0.03dB) at the BERs of 10-2, 10-4, 10-6 respectively with sixteen iterations.

The presented simulation results are implemented using (Matlab version R2011b) and shown that the performances of the non-binary TCM-based the new and the TTCM decoding algorithms outperform the binary decoding methods and suitable to deal with error control coding of the STBC-OFDM schemes that candidate with the (4G) of the wireless communication systems.

Main Subjects

Telecommunications Engineering
Electronic engineering

No. of Pages

143

Table of Contents

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• MLA
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Language

English

Data Type

Arab Theses

Record ID

BIM-745121