Abstract
OFDM is widely attracting attention and is examined for practical use. In order to improve performance of OFDM under severe conditions, it is necessary to take measures against various factors of degradation of characteristics. As one of the factors of degradation of OFDM characteristics, influence of impulse noise must be considered. In OFDM transmission, performance is degraded by the existence of time domain impulse noise because this noise has very wide bandwidth, and it affects all the carriers in the OFDM signal. Especially, the influence of impulse noise with large amplitude cause severe degradation. Moreover, the influence of multi-path channel cause severe degradation. In this paper, a scheme that iteratively reduces the influence of impulse noise is proposed. In the proposed scheme, the symbols after decision are re-modulated to generate a time domain OFDM signal to replace the samples that are degraded by the impulse noise in the time domain. The time domain OFDM signal is demodulated again after the influence of the impulse noise is reduced. Moreover, By repeating this procedure iteratively changing the thres Thold value, further improvement is achieved.
