A Robust Broadcast System Under Time- Varying Channels Based on OTFS Modulation

This paper proposes a robust broadcast system under time-varying channels based on an orthogonal time frequency space (OTFS) modulation. The OTFS modulation can reduce an effect of inter-carrier interference (ICI), which results from a Doppler shift, by mapping modulation symbols to a two-dimensional delay-Doppler domain. Therefore, the OTFS modulation can obtain robust reception performance under very rapid time-varying channels compared to orthogonal frequency division multiplexing (OFDM). Furthermore, the OTFS modulation can be regarded as pre- and post-processing of the OFDM system, and therefore the OTFS modulation can be easily applied to the OFDM system. Using these advantages of the OTFS modulation, the proposed broadcast system can reliably transmit high-quality services under high mobility conditions. Simulation results show that the proposed broadcast system based on the OTFS modulation outperforms the conventional Advanced Television Systems Committee (ATSC) 3.0 system under high Doppler shift environments.