Performance comparison of Wavelet based and conventional OFDM systems - A review

Growth in technology has led to unprecedented demand for high speed architectures for complex signal processing applications. In 4G wireless communication systems, bandwidth is a precious commodity, and service providers continuously met with the challenge of accommodating more users with in a limited allocated bandwidth. To increase data rate of wireless medium with higher performance, OFDM (orthogonal frequency division multiplexing) is used. OFDM is multicarrier modulation (MCM) technique which provides an efficient means to handle high speed data streams on a multipath fading environment that causes ISI. Normally OFDM is implemented using FFT and IFFT’s. To decrease the bandwidth waste brought by adding cyclic prefix, Wavelet based OFDM is employed. Due to use of wavelet transform the transmission power is reduced. In this paper we review the replacement of Fourier transform by Wavelet transform and its effects on the overall system. Index Terms – BER, DFT, FFT, OFDM