The use of OTFS in a multi-satellite scenario to improve the performance of future non-terrestrial networks developed within the DYNASAT project was the topic of the paper discussed at the joint 27th Ka and Broadband Communications Conference (Ka) and 39th International Communications Satellite Systems Conference (ICSSC), held in Stresa, Italy in October 2022.
The paper “Multi-Satellite Diversity Through the Use of OTFS“, submitted by the DYNASAT partner University of Parma (SPADiC Lab), was presented by the researcher Alessandro Ugolini on October 21, 2022. Download the full presentation here.
about the paper
Title: “Multi-Satellite Diversity Through the Use of OTFS”
Authors: S. Buzzi, G. Caire, G. Colavolpe, C. D’Andrea, T. Foggi, A. Piemontese, and A. Ugolini, University of Parma
Abstract: We consider the use of multiple low-Earth orbit (LEO) satellites to improve the spectral efficiency of beyond-5G (B5G) non-terrestrial networks. In these networks, the use of LEO constellations is foreseen to ensure a global coverage and, typically, multiple satellites are in visibility with the user terminal. In a scenario like this, we consider the adoption of the orthogonal time frequency space (OTFS) modulation. In this modulation format, conceived for doubly-selective terrestrial channels, the information symbols are placed in the Doppler-delay (DD) domain, wherein the time-varying channels are quasi-static and sparse. Through proper pilot schemes and channel estimation algorithms, the Doppler-delay pairs and the channel gains of the different scatterers of a terrestrial channel can be estimated and coherent detection can be then performed. The same channel estimation and detection algorithms also enable the exploitation of diversity, in case of multiple satellites transmitting the same OTFS signal. The different satellites will be, in fact, characterized by different Doppler-delay pairs and channel gains, making the scenario similar to the case of wireless channels with different scatterers. A cell-free architecture can be thus conceived with a significant improvement with respect to a scenario where each user is served by a single satellite.
About Ka and ICSSC conferences
The Ka and ICSSC conferences represent the two most influential technical conferences on satellite systems. The conferences gather every year researchers and innovators at work on telecommunications, particularly focusing on navigation and remote sensing satellite systems for Earth observation and space exploration.