Precoded OFDM With Spectrum-Aligned DFT for Extreme Doppler UWA Channels
Orthogonal Frequency-Division Multiplexing (OFDM) systems without in-band pilots suffer from catastrophic Inter-Carrier Interference (ICI) and irreducible error floors when subjected to extreme Carrier Frequency Offset (CFO). While cross-domain waveforms like OTFS address high Doppler spreads, their detection complexit...