Adaptive co-existence of OFDM and OTFS for Multi-Mobility scenarios in wireless communications

Abstract

The rapid evolution of technology necessitates the development of new waveforms capable of handling the increasing demands of high-mobility scenarios. Orthogonal Frequency Di-vision Multiplexing (OFDM), although extensively used in current wireless communication systems, experiences significant performance degradation in highmobility environments due to large Doppler shifts and Doppler spread effects .To address these challenges, a novel waveform called Orthogonal Time Frequency Space (OTFS) has been developed, offer ingsuperior performance in highmobility scenarios by exploiting delay-Doppler diversity. However, OTFS introduces high processing complexity and does not exhibit obvious performance advantages for low-mobility users, where OFDM remains efficient and effective. There fore, there is a critical need to develop a co-existence method that leverages the strengths of both waveforms. we proposed a method to check the user’s velocity and dynamically switch between OFDM and OTFS based on user mobility. By doing so, the communication system can achieve optimal performance of Bit Error Rate (BER) versus Signal-to-Noise Ratio (SNR), maintaining robust and efficient data transmission across diverse mobility conditions.