Fnhancement of dwt-of dm-cdma system using turbo coding

مقدم أطروحة جامعية

Hadi, Wail A. H.

الجامعة

الجامعة التكنولوجية

الكلية

-

القسم الأكاديمي

قسم الهندسة الكهربائية

دولة الجامعة

العراق

الدرجة العلمية

دكتوراه

تاريخ الدرجة العلمية

2006

الملخص الإنجليزي

In mobile radio environment, signals are usually impaired by fading and multipath delay spread phenomenon.

In such a channel, severe fading of the signal amplitude and Intersymbol Interference (ISI) lead to unacceptable degradation of the system error performance.

It is expected that Orthogonal Frequency Division Multiplexing (OFDM) is capable of providing very high data rate with strong robustness of multipath delay spread, which makes IS] no longer a problem.

Adding a Cyclic Prefix (CP) is the main way for the Fourier based OFDM to eliminate the ISI and Intermarried Interference (ICI) to decrease the bandwidth waste brought by adding CP.

a discrete wavelet based OFDM (DWT-OFDM) is adopted due to its excellent orthogonality between subcarriers and efficient spectral containment.

For further enhancement, a combination of Code Division Multiple Access (CDMA) system and OFDM system is proposed.

The combination OFDM signaling and CDMA scheme has major advantage that it can Lowe the symbol role in each subcarrier so that longer symbol duration makes i easier to synchronize the transmission.

In this work, three OFDM-CDM/ system models are investigated.

Furthermore, a DWT-OFDM-CDMA system models and D WT-OFDM-DS-CDMA system model is proposed.

Finally, a Turbo Coded OFDM (Turbo-COFDM) has been adopted t< enhance the bit error rate performance of investigated and proposed systems A parallel concatenation convolutional code (PCCC) is used in the propose Systems.

In this work, all OFDM system models are investigated and tested ove simulated Rayleigh fading mobile radio channel.

Jakes model is used in this work for channel modeling and simulation.

All investigated and proposed systems are implemented and tested under different parameters using MATLAB version 7.

The Bit Error Rat.

التخصصات الرئيسية

الهندسة الكهربائية

الموضوعات

• برمجيات الحاسوب

• APA
• MLA
• AMA

لغة النص

الإنجليزية

نوع البيانات

رسائل جامعية

رقم السجل

BIM-305930