Orthogonal frequency division multiplexing (OFDM) is a unique scheme of multicarrier transmission where a single data stream is transmitted over a number of lower rate subcarriers. OFDM is a promising technology for good bandwidth efficiency. Recently, a worldwide convergence has occurred for the use of OFDM as an emerging technology such as Wi-Max, IEEE802.11a, 4th generation long term evolutionary (LTE), DVB etc., have adopted the OFDM technology as a mean to increase the data rate for future wireless communications. OFDM is most suitable for high speed, wide bandwidth and frequency selective wireless transmission. In this paper we discuss the overview and the performance evaluation results of an implementation of fast Fourier transform (FFT) and discrete wavelet transform (DWT) OFDM systems. FFT OFDM system utilizes the cyclic prefix (CP) to mitigate the effect of inter symbol interference (ISI) produced by the multipath effect of wireless channel. DWT OFDM systems due to overlapping nature of their properties don’t need cyclic prefix and thereby increase bandwidth efficiency by 25%. The results obtained shows that the probability of error in the DWT-OFDM scheme is improved in many scenarios, even though the CP is not used, which leads to less overheads and reduced ISI.Keywords: BER (Bit Error Rate), DWT, FFT, OFDMCite this ArticleShashidhara KS, Chaitrashree CN, Balaji T et al. Performance analysis of FFT-OFDM and DWT-OFDM and its implementation. Recent Trends in Electronic and Communication Systems. 2016; 3(1): 1–8p.
