Integrated satellite-terrestrial connectivity for autonomous ships:Survey and future research directions

An autonomous vessel uses multiple different radio technologies such as satellites, mobile networks and dedicated narrowband systems, to connect to other ships, services, and the remote operations center (ROC). In-ship communication is mainly implemented with wired technologies but also wireless links can be used. In this survey paper, we provide a short overview of autonomous and remote-controlled systems. This paper reviews 5G-related standardization in the maritime domain, covering main use cases and both the role of autonomous ships and that of people onboard. We discuss the concept of a connectivity manager, an intelligent entity that manages complex set of technologies, integrating satellite and terrestrial technologies together, ensuring robust in-ship connections and ship-to-outside connections in any environment. This survey paper describes the architecture and functionalities of connectivity management required for an autonomous ship to be able to operate globally. As a specific case example, we have implemented a research environment consisting of ship simulators with connectivity components. Our simulation results on the effects of delays to collision avoidance confirm the role of reliable connectivity for safety. Finally, we outline future research directions for autonomous ship connectivity research, providing ideas for further work

Database-assisted spectrum sharing in satellite communications:A survey

This survey paper discusses the feasibility of sharing the spectrum between satellite telecommunication networks and terrestrial and other satellite networks on the basis of a comprehensive study carried out as part of the European Space Agency's (ESA) Advanced Research in Telecommunications Systems (ARTES) programme. The main area of investigation is the use of spectrum databases to enable a controlled sharing environment. Future satellite systems can largely benefit from the ability to access spectrum bands other than the dedicated licensed spectrum band. Potential spectrum sharing scenarios are classified as: a) secondary use of the satellite spectrum by terrestrial systems, b) satellite system as a secondary user of spectrum, c) extension of a terrestrial network by using the satellite network, and d) two satellite systems sharing the same spectrum. We define practical use cases for each scenario and identify suitable techniques. The proposed scenarios and use cases cover several frequency bands and satellite orbits. Out of all the scenarios reviewed, owing to the announcement of many different mega-constellation satellite networks, we focus on analysing the feasibility of spectrum sharing between geostationary orbit (GSO) and non-geostationary orbit (NGSO) satellite systems. The performance is primarily analysed on the basis of widely accepted recommendations of the Radiocommunications Sector of the International Telecommunications Union (ITU-R). Finally, future research directions are identified

Coexistence of DTT and Mobile Broadband: A Survey and Guidelines for Field Measurements

This article provides a survey and a general methodology for coexistence studies between digital terrestrial television (DTT) and mobile broadband (MBB) systems in the ultra high frequency (UHF) broadcasting band. The methodology includes characterization of relevant field measurement scenarios and gives a step-by-step guideline on how to obtain reliable field measurement results to be used in conjunction with link budget analyses, laboratory measurements, and simulations. A survey of potential European coexistence scenarios and regulatory status is given to determine feasible future use scenarios for the UHF television (TV) broadcasting band. The DTT reception system behavior and performance are also described as they greatly affect the amount of spectrum potentially available for MBB use and determine the relevant coexistence field measurement scenarios. Simulation methods used in determining broadcast protection criteria and in coexistence studies are briefly described to demonstrate how the information obtained from field measurements can be used to improve their accuracy. The presented field measurement guidelines can be applied to any DTT-MBB coexistence scenarios and to a wide range of spectrum sharing and cognitive radio system coexistence measurements.</p

Avaruus arjessamme : Avaruustoiminnan yhteiskunnallinen vaikuttavuus (AVARTAVA) loppuraportti

Selvityksen tavoitteena oli muodostaa ajankohtainen kuva siitä, miten avaruustoiminnan mahdollisuuksia hyödynnetään hallitusohjelman tavoitteiden ja muiden yhteiskunnallisten tavoitteiden toteuttamisessa sekä eri hallinnonalojen päätöksenteossa. Päähavainto on, että avaruustoimintaa hyödynnetään laajasti eri hallinnonalojen päätöksenteossa sekä hallitusohjelman ja muiden yhteiskunnallisten tavoitteiden toteuttamisessa, vaikka avaruustoiminnan roolia aina ei välttämättä tiedosteta. Avaruustoiminnan palveluilla, kuten paikkatiedolla ja aikasignaalilla, kaukokartoituksella ja satelliittitietoliikenteellä on merkittäviä sovelluksia viranomaistoiminnassa, esim. pelastuksessa, ympäristövalvonnassa ja turvallisuusviranomaisten toiminnassa, sekä liike-elämässä, erilaisten tietoliikenne- ja energiaverkkojen, kaupankäynnin, kuljetusten ja palveluiden mahdollistajana. Kaiken kaikkiaan avaruustoiminta on kriittistä yhteiskunnan normaalille toiminnalle. Selvitysryhmä suosittaakin tiedostamaan avaruustoiminnan roolin kriittisyyden. Selvityksessä esitetään toimenpiteitä tarvittavan osaamisen ja resurssien varmistamiseksi, jotta avaruustoiminnan palveluita voidaan hyödyntää jatkossa entistä laajemmin.Tämä julkaisu on toteutettu osana valtioneuvoston selvitys- ja tutkimussuunnitelman toimeenpanoa. (tietokayttoon.fi) Julkaisun sisällöstä vastaavat tiedon tuottajat, eikä tekstisisältö välttämättä edusta valtioneuvoston näkemystä