BER comparison of DCT-OFDM and DFT-OFDM for different modulation techniques in multipath Rayleigh fading environment

In wireless communication Orthogonal Frequency Division Multiplexing is gaining its importance as it is suitable for high speed data rates. It is a multi carrier system, which is commonly implemented for transmission of signals nowadays. In this system, orthogonally placed sub-carriers are used to carry data from transmitter end to receiver end. In this paper, Bit Error Rate comparison of Discrete Fourier Transform-based Orthogonal Frequency Division Multiplexing is compared with Discrete Cosine Transform-based Orthogonal Frequency Division Multiplexing for different modulation techniques over Multipath Rayleigh Fading Channel. It is observed from results that, Bit Error Rate shift in case of Discrete Cosine Transform-based Orthogonal Frequency Division Multiplexing is less then compared to Bit Error Rate shift in case of Discrete Fourier Transform-based Orthogonal Frequency Division Multiplexing system and Quadrature Amplitude Modulation shows better performance as compared to Phase Shift Keying for higher constellation index.