Digital Communications and Networks (Nov 2018)
Design of a novel hybrid intercarrier interference mitigation technique through wavelet implication in an OFDM system
Abstract
Orthogonal Frequency Division Multiplexing (OFDM) is the most preferred and widely used multiplexing technique in current wireless environment for sidelining the spectrum scarcity problem by splitting a signal into N signals and subsequently modulating them through several orthogonal subcarriers (which bears high frequency). With several great features, OFDM is severely affected by undesirable effects of frequency offset errors and Local Oscillator (LO) frequency synchronization errors. This paper proposes an approach that devises a new hybrid technique, which is a combination of Maximum Likelihood Estimation (MLE) and Self Cancellation (SC) techniques through wavelet implication, to enhance BER performance of the OFDM system. A comparative analysis of SC, MLE, and wavelet-based hybrid InterCarrier Interference (ICI) cancellation techniques was conducted using 64-QAM and differential offset (0.02 and 0.01) for differential data bits (4 Mb and 16 Mb) to justify the outstanding results. The simulation results showed a significant byte-error-rate improvement over different legacy techniques based on fast Fourier transform. Index terms: OFDM, WOFDM, DWT, FFT, ISI, ICI, MLE, SC