AUTHOR=Mosquera Carlos , Arapoglou Pantelis-Daniel TITLE=Editorial: Signal Processing for Beyond 5G Non-Terrestrial Networks JOURNAL=Frontiers in Space Technologies VOLUME=2 YEAR=2021 URL=https://www.frontiersin.org/journals/space-technologies/articles/10.3389/frspt.2021.780171 DOI=10.3389/frspt.2021.780171 ISSN=2673-5075