Open AccessLEO Satellite Diversity in 6G Non-Terrestrial Networks: OFDM vs. OTFS
Author(s) -
Stefano Buzzi,
Giuseppe Caire,
Giulio Colavolpe,
Carmen D'Andrea,
Tommaso Foggi,
Amina Piemontese,
Alessandro Ugolini
Publication year - 2023
Publication title -
ieee communications letters
Language(s) - English
Resource type - Journals
eISSN - 1558-2558
pISSN - 1089-7798
DOI - 10.1109/lcomm.2023.3320793
Subject(s) - communication, networking and broadcast technologies
Non-terrestrial networks will play a crucial role in future wireless 6G systems to ensure ubiquitous connectivity and to complement terrestrial networks. With reference to a low Earth orbit (LEO) constellation, this letter performs a comparison in terms of pragmatic capacity between the orthogonal frequency division multiplexing (OFDM) and the orthogonal time frequency space (OTFS) modulation in a scenario where multi-satellite diversity is employed to ensure a more uniform throughput and to increase the system reliability against unforeseen blockages. The considered scenario is akin to a cell-free system, wherein each user may be jointly served by multiple satellites for better and more stable performance. Numerical results reveal that multi-satellite diversity is effective in increasing the link performance and that OTFS provides a better performance and is thus more robust to the impairments caused by the heavy Doppler shifts.