Abstract

Satellite communication systems are mostly operated in isolation from the terrestrial network systems. Although satellite phone services, VSAT (Very small aperture terminal) data services, and television broadcast services are available for a long time, the satellites have been used as bent pipes for relaying communication signals between gateway earth stations and user terminals. Moreover, for mobile users the seamless handovers from a satellite coverage to a terrestrial cellular network coverage and vice versa are still not supported.
To offer low-latency and high data rate communication services not only in cities by advanced terrestrial mobile networks such as the 5G network system, but also everywhere on the earth (remote agriculture farms, mountains, deserts, sea, and air) as well as in space, integration of satellite-based non-terrestrial networks (NTN) and terrestrial networks (TN) is indispensable.
This talk begins with the background of satellite communications, giving examples of satellite types deployed in various orbits such as low-earth orbit (LEO), mid-earth orbit (MEO), and geostationary earth orbit (GEO), which are deployed at different altitudes. Literature on the research and development of technologies for the integration of terrestrial and non-terrestrial networks is reviewed. Then the relevant standardization activities of various standards development organizations (SDOs) such as ITU and 3GPP are presented. Finally, the key challenges of TN/NTN integration and the possible approaches to address them are summarized.

Biography

Ved P. Kafle received the B.E. (Honours) degree in Electronics and Communications from Punjab Engineering College, India, the M.S. degree in Computer Science and Engineering from Seoul National University, South Korea, and the Ph.D. degree in Informatics from the Graduate University for Advanced Studies, Japan. He is currently a research manager at National Institute of Information and Communications Technology (NICT), Tokyo. He has been serving as a Rapporteur of ITU-T Study Group 13 (SG13) since 2014 for the standardization of upcoming networking technologies. His current research interests include network architectures, Beyond-5G networks, network control and service automation by AI and machine learning, network function virtualization, software defined networking, and terrestrial and non-terrestrial network convergence. He received the ITU Association of Japan's Encouragement Award and Accomplishment Award in 2009 and 2017, respectively. He received four Best Paper Awards from the ITU Kaleidoscope Academic Conference in 2009, 2014, 2018 and 2020. He received Nepali Diaspora ICT Award in 2022 from Nepal and the Information and Communication Technology Award (President Commendation) from the Telecommunication Technology Committee (TTC), Japan in 2023. He is a fellow of ITU-T SG13, a life member of Nepal Engineers Association, a senior member of IEEE and a member of IEICE.