OTFS for 6G wireless networks: efficient communication and sensing

Orthogonal Time Frequency Space (OTFS) modulation has emerged as a promising waveform for next-generation wireless systems, particularly well-suited to high-mobility and doubly dispersive environments. By representing signals in the delay-Doppler (DD) domain, OTFS efficiently exploits channel sparsity and improves resilience to time and frequency selectivity. In addition to its high spectral efficiency (SE) for communication, OTFS is advantageous for sensing, as parameters such as range and Doppler align naturally with the DD-domain channel response, enabling accurate target localization. These features make OTFS a strong candidate for integrated sensing and communication (ISAC), attracting growing attention from both academia and industry. This thesis focuses on the application of OTFS in wireless communication and ISAC systems, addressing several open research problems critical to its practical deployment.