Performance of coded DMT system with account for temporal dynamics of impulsive noise

Abstract

To implement data communications over power- lines multicarrier modulation (such as Discrete MultiTone, DMT) is widely adopted. One of important features of powerline channels is the presence of strong impulsive noise. The length of modulation symbol in practical DMT systems is comparable with average length of noise pulses. In the article the impact of impulsive noise on performance of a coded DMT system is analyzed. The temporal dynamics of noise is described by two-level Markov model. Theoretic results and simulation lead to the following conclusions: with practical values of the ratio between noise impulse length and DMT symbol length, non-stationary nature of impulsive noise can noticeably affect performance of DMT systems; DFT leads to effective normalization of noise if average duration of noise pulses does not exceed 1% of DMT symbol length; during the noise burst the loss due to the impulsive nature of noise varies in the range of 1...2 dB.