Wavelet based multicarrier CDMA system

Abstract

Emerging demands for high data rate services, high user capacity and low power consumption systems are the key driving forces behind the continued technology evolution in wireless communications. Multicarrier Modulation techniques support variety of services requiring different data rates and different QoS (quality of service) levels. Multicarrier CDMA is a wireless communication system that can be seen as a combination of direct sequence CDMA and Orthogonal Frequency Division Multiplexing techniques. The main benefits of this system are its robustness to inter symbol interference and multipath propagation in fading channels. This paper studies and simulates the Discrete Wavelet Transform based Multicarrier CDMA and compares it with the Discrete Fourier Transform based one using different number of sub carriers, and different modulation techniques. The results shows that the Wavelet based system outperforms the Fourier based one since it has lower bit error rate BER performance, lower peak to verage power ratio PAPR and higher user capacity.

A Novel Selected Subcarrier Method for Digital Video Broadcasting

“…Wavelet OFDM is the challenging technique in multicarrier transmission scheme .recent years, the application of wavelet OFDM in the broadcasting system is keeping on increasing .many areas like hybrid power line communication [9], visible light communication [9],5G communication [10], [11], cognitive radio [12], Multicarrier CDMA [13], UWB system, cognitive UWB [14], and satellite communication uses wavelet OFDM. In conventional FFT there is a requirement cyclic prefix insertion to reduce the intersymbol interference, which consumes large bandwidth.…”

A review on sparse fast fourier transform applications in image processing

“…Fourier Transform is first introduced by Jean Baptiste Joseph Fourier [1] to solve the computational complexity in wide varities of fields including earth and science, chemistry, communications, and signal processing [2][3][4][5]. In signal processing, Fourier Transform [6][7][8][9][10][11] has long been established as an instrumental tool applied in electrical signal spectrum and filter analysis, sampling and series, antenna, television image convolution as well as radio broadcasting [1]. Being the limiting case of Fourier Series for non-periodic signals, FT is used to convert signal to frequency domain as the frequency domain has many superlative benefits especially for analytical purposes rather than in the classical time domain.…”