Doppler Resilient Orthogonal Time-Frequency Space (OTFS) Systems Based on Differential Chaos Shift Keying

This paper introduces a novel system that leverages Differential Chaos Shift Keying (DCSK) with Orthogonal Time-Frequency Space (OTFS) technique. Different from other DCSK systems, the proposed scheme adopts modulation for both chaotic reference symbols and information-carrying symbols in the Doppler-delay (DD) domain of OTFS. To mitigate complexity concerns, a low-complexity strategy based on Maximum Ratio Combining (MRC) detection is then proposed. To assess the performance of the OTFS-DCSK, simulations are performed using the Extended Vehicular A channel model (EVA) defined by the 3GPP standard. The results reveal that OTFS-DCSK scheme outperforms the conventional OFDM-DCSK in terms of reliability and robustness when subjected to high-speed motion scenarios. These results provide valuable practical guidance, affirming the effectiveness of our novel design.