Advanced OTFS based Communication System for beyond 5G Networks
Keywords:
6G, B5G, Delay–Doppler domain, Doppler spread, Doubly selective channel, GNU-Radio prototype, ISFFT/SFFT, MATLAB simulation, OFDM comparison, OTFS, SDR implementation, Symbol-error rate, URLLCAbstract
This work investigates OTFS modulation as a potential waveform for Beyond 5G (B5G) and future 6G systems by simulating its performance in realistic channels. OTFS is particularly suited for environments with high Doppler shifts and delay dispersion, where conventional OFDM becomes ineffective. An end-to-end OTFS transceiver prototype was developed using GNU Radio and MATLAB, with performance compared against OFDM in high-mobility multipath fading channels. Key components such as ISFFT/SFFT processing, QAM mapping, delay–Doppler channel modeling, and MMSE equalization are carefully addressed. Simulation results demonstrate that OTFS maintains constellation shape under Doppler shifts up to 1 kHz and achieves slightly lower symbol-error rates than OFDM at equivalent SNR levels. These findings support OTFS as a promising candidate for ultra-reliable low-latency communications and vehicle-to-vehicle (V2V) links in future wireless standards. Furthermore, the work provides an open-access MATLAB/GNU Radio platform, encouraging future experimentation and potential upgrades toward FPGA or software-defined radio (SDR) implementations for practical 6G development.
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