The amplitude and phase components of the modulation spectrum were dissociated in order to ascertain the importance of cross-spectral, envelope-modulation phase information for understanding spoken language. The dissociation was effected via local time reversals of the speech waveform (i.e., flipping the signal on its horizontal axis) at intervals ranging between 0 and 180 ms. Intelligibility d...

We propose a concatenated code structure combined with high-order modulations suitable for implementation with iterative decoders operating at gigabit-persecond (Gbps) data rates. The examples considered in this article are serial/parallel concatenations of Hamming and accumulator codes. Performance results are given for binary phase-shift keyed (BPSK) modulation, quadrature phase-shift keyed (...

The effect of self-phase modulation in chirped-pulse amplification is investigated. A numerical model is used to predict the effects of phase modulation on pulse recompression, and experimental results are presented that agree well with the calculations. We show that even moderate self-phase modulation can significantly distort the recompressed pulse after amplification, thereby reducing the pe...