Performance Analysis of Multicarrier Code Division Multiple Access (MC-CDMA) Systems

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Pravinkumar Patil on August 11, 2008

BER Performance Simulation of Generalized MC DS-CDMA System with Time-Limited Blackman Chip Waveform

Multiple access interference encountered in multicarrier direct sequence-code division multiple access (MC DS-CDMA) is the most important difficulty that depends mainly on the correlation properties of the spreading sequences as well as the shape of the chip waveforms employed. In this paper, bit error rate (BER) performance of the generalized MC DS-CDMA system that employs time-limited Blackman chip waveform is presented for Nakagami-m fading channels. Simulation results show that the use of Blackman chip waveform can improve the BER performance of the generalized MC DS-CDMA system, as compared to the performances achieved by using timelimited chip waveforms in the literature

OFDM comparison with FFT and DWT processing for DVB-T2 wireless channels

Introduction− Recent studies on the FFT processing (Fast Fourier Transform) or DWT (Discrete Wavelet Transform) of the OFDM signal (Orthogonal Frequency Division Multiplexing) have shown pros and cons for DVB-T2 (Digital Video Broadcasting-Second Generation Terrestrial) radio communications; however, the benefits of both types of processing have yet to be compared for the same scenario. Objective− The objective of this research is to compare the response of the wireless channel with AWGN noise (Additive White Gaussian Noise Channel) and Rayleigh and Rician fading in the UHF (Ultra High Frequency) bandMethodology−The transmission of DVB-T2 information with OFDM modulation and FFT and DWT processing was simulated in Matlab®, specifically in Simulink. Results− The results of the study proved to be more ef-ficient for DWT system than FFT system, due to the low rate of erroneous bits, spectral efficiency and reduction of the Peak-to-Average Power Ratio (PAPR), for Eb / No relations greater than 10dB. Conclusions−In this article, we present the designs of both systems and the results of the research experience; likewise, the practical applicability of these systems is discussed, and improvements are suggested for future work.Introducción− Recientes estudios sobre el procesado FFT (Fast Fourier Transform) o DWT (Discrete Wavelet Transform) de la señal OFDM (Orthogonal Frequency Di-vision Multiplexing) han demostrado pros y contras para comunicaciones de radio DVB-T2 (Digital Video Broad-casting – Second Generation Terrestrial); sin embargo, aún falta comparar las prestaciones de ambos tipos de procesamiento para el mismo escenario. Objetivo− El objetivo de esta investigación es comparar la respuesta del canal inalámbrico con ruido AWGN (Ad-ditive White Gaussian Noise Channel) y desvanecimiento Rayleigh y Rician en la banda de UHF (Ultra High Fre-quency).Metodología− Se simuló en Matlab®, específicamente en Simulink, la transmisión de información DVB-T2 con modulación OFDM y procesado FFT y DWT. Resultados− Los resultados del estudio demostraron ser más eficientes para el sistema DWT en comparación con el Sistema FFT, por la baja tasa de bits errados, eficiencia espectral y reducción del cociente entre la potencia pico a promedio (PAPR: Peak-to-Average Power Ratio), para relaciones Eb/No mayores a 10dB. Conclusiones− En este artículo se presentan los diseños de ambos sistemas y los resultados de la experiencia de investigación; así mismo, se discute la aplicabilidad práctica de estos sistemas y se sugieren mejoras para trabajos futuros

Comparación OFDM con procesado FFT y DWT para canales inalámbricos DVB-T2

Introduction: Recent studies on the FFT processing (Fast Fourier Transform) or DWT (Discrete Wavelet Transform) of the OFDM signal (Orthogonal Frequency Division Multiplexing) have shown pros and cons for DVB-T2 (Digital Video Broadcasting-Second Generation Terrestrial) radio communications; however, the benefits of both types of processing have yet to be compared for the same scenario. Objective: The objective of this research is to compare the response of the wireless channel with AWGN noise (Additive White Gaussian Noise Channel) and Rayleigh and Rician fading in the UHF (Ultra High Frequency) band. Methodology: The transmission of DVB-T2 information with OFDM modulation and FFT and DWT processing was simulated in Matlab®, specifically in Simulink. Results: The results of the study proved to be more efficient for DWT system than FFT system, due to the low rate of erroneous bits, spectral efficiency and reduction of the Peak-to-Average Power Ratio (PAPR), for Eb / No relations greater than 10dB. Conclusions: In this article, we present the designs of both systems and the results of the research experience; likewise, the practical applicability of these systems is discussed, and improvements are suggested for future work.Introducción: Recientes estudios sobre el procesado FFT (Fast Fourier Transform) o DWT (Discrete Wavelet Transform) de la señal OFDM (Orthogonal Frequency Division Multiplexing) han demostrado pros y contras para comunicaciones de radio DVB-T2 (Digital Video Broadcasting – Second Generation Terrestrial); sin embargo, aún falta comparar las prestaciones de ambos tipos de procesamiento para el mismo escenario. Objetivo: El objetivo de esta investigación es comparar la respuesta del canal inalámbrico con ruido AWGN (Additive White Gaussian Noise Channel) y desvanecimiento Rayleigh y Rician en la banda de UHF (Ultra High Frequency). Metodología: Se simuló en Matlab®, específicamente en Simulink, la transmisión de información DVB-T2 con modulación OFDM y procesado FFT y DWT. Resultados: Los resultados del estudio demostraron ser más eficientes para el sistema DWT en comparación con el Sistema FFT, por la baja tasa de bits errados, eficiencia espectral y reducción del cociente entre la potencia pico a promedio (PAPR: Peak-to-Average Power Ratio), para relaciones Eb/No mayores a 10dB. Conclusiones: En este artículo se presentan los diseños de ambos sistemas y los resultados de la experiencia de investigación; así mismo, se discute la aplicabilidad práctica de estos sistemas y se sugieren mejoras para trabajos futuros