Discrete Pulse OTFS Waveform Scheme: Transceiver Design and Parameter Optimization

Orthogonal time frequency space (OTFS) is a novel modulation scheme that effectively mitigates multipath fading and Doppler shifts. Moreover, certain scenarios such as forward collision warning and emergency signal transmission in vehicle-to-everything (V2X) systems impose stringent requirements on low-latency communications under high-speed conditions. In this paper, we propose a discrete pulse orthogonal time frequency space (DP-OTFS) waveform scheme that enables low-latency communication in multipath high-speed scenarios by realizing logical full-duplex communication. Additionally, we model the transmit-receive collision channel and multi-node collision channel, and propose a signal detection method based on the collision mask matrix in full-duplex mode. Regarding the bit error rate (BER) performance, we innovatively define the collision impact factor (CIF) by leveraging OTFS characteristics to more accurately quantify the actual impact of collisions on system performance. Furthermore, we formulate and solve an optimization problem aimed at minimizing BER caused by inter-signal conflicts through time-hopping sequence (THS) adjustment. Simulation results demonstrate that the proposed DP-OTFS waveform exhibits both full-duplex capability and robustness against multipath Doppler interference. Compared with OTFS, DP-OTFS enables simultaneous signal transmission and reception, thus significantly improving spectral efficiency and reducing communication latency. In contrast, conventional OTFS experiences severe BER degradation under transmit-receive and multi-node collision scenarios, which renders it unable to maintain reliable communication.