Algorithm for modulation recognition in shortwave channel environment
Wang Zanji · Chinese Journal of Radio Science · 2007
The shortwave channel is a kind of time-variant multipath channel with impulsive noise and Gauss noise.The method of zero-memory non-linearity system and segmental blind equalization is proposed for modulation recognition.An ideal zero-memory non-linearity system transforms the impulsive noise to Gauss noise,leaving the signal intact.Segmental equalization relieves the influence on equalizer caused by time-variant channel and error of parameters estimation.The results of equalization have much difference because of remain impulsive noise and time-variant channel.The optimal equalized segmentation determining the modulation type is selected by the maximum posterior probability.Simulation results show average successful rates are more than 90% in shortwave channels with impulsive noise when SNR is above 10dB.