Comprehensive Study on DWT-OFDM and FFT-OFDM using 64-DAPSK Modulation Technique

  Chelsy Joy

Orthogonal Frequency Division Multiplexing (OFDM) that has high performance over multipath environments is a multicarrier modulation scheme which is used in many wireless applications. Data transmission and reception is through orthogonally separated narrow-band sub-carriers. it is implemented using Discrete Fourier transform (DFT) and IDF T.OFDM usually adopts binary phase shift keying (BPSK), quadrature amplitude modulation (QAM) or quadrature phase shift keying (QPSK) as the modulation scheme. In this paper a MATLAB simulation for the comparison of a discrete wavelet transform (DWT) based OFDM with DFT based system with differential amplitude phase shift keying (DAPSK) as its modulation scheme is presented. The performance in multipath fading as channel impairments in the presence of Additive white Gaussian noise (AWGN) was evaluated and explained in terms of bit error rate (BER) and peak average power ratio (PAPR). The results shows that DWT based OFDM systems are superior to a DFT based system with 64-DAPSK modulation. Also 64-DAPSK reduced the implementation complexity of the receiver, as it doesn’t need channel estimation or equalization and compensates the channel effect on the signal without the need of any previous knowledge of the channel.

Keywords- OFDM, DAPSK, BER, PAPR, DWT-OFDM

Unique Identification Number - IJEDR1602002
Page Number(s) - 7-17
Pubished in - Volume 4 | Issue 2 | April 2016
DOI (Digital Object Identifier) -   
Publisher - IJEDR (ISSN - 2321-9939)

  Chelsy Joy,   "Comprehensive Study on DWT-OFDM and FFT-OFDM using 64-DAPSK Modulation Technique", International Journal of Engineering Development and Research (IJEDR), ISSN:2321-9939, Volume.4, Issue 2, pp.7-17, April 2016, Available at :http://www.ijedr.org/papers/IJEDR1602002.pdf