International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The proliferation of Low Earth Orbiting (LEO) science, earth resources and eventually global communications satellites either in orbit or planned, requires a much lower cost methodology for ground support. No longer is it economically feasible to consider a single, dedicated satellite tracking station to service a LEO spacecraft. An innovative approach is needed to lower the cost of LEO satellite data services thus contributing to the expansion of the commercial space market. This appraisal will cover the performance aspects needed for LEO tracking support and offer a unique and new solution to providing TT&C and payload services.

Forest fires cause a significant amount of damage and destruction each year. Optimally dispatching resources reduces the amount of damage a forest fire can cause. Models predict the fire spread to provide the data required to optimally dispatch resources. However, the models are only as accurate as the data used to build them. Satellites are one valuable tool in the collection of data for the forest fire models. Satellites provide data on the types of vegetation, the wind speed and direction, the soil moisture content, etc. The current operating paradigm is to passively collect data when possible. However, images from directly overhead provide better resolution and are easier to process. Maneuvering a constellation of satellites to fly directly over the forest fire provides higher quality data than is achieved with the current operating paradigm. Before launch, the location of the forest fire is unknown. Therefore, it is impossible to optimize the initial orbits for the satellites. Instead, the expected cost of maneuvering to observe the forest fire determines the optimal initial orbits. A two-stage stochastic programming approach is well suited for this class of problem where initial decisions are made with an uncertain future and then subsequent decisions are made once a scenario is realized. A repeat ground track orbit provides a non-maneuvering, natural solution providing a daily flyover of the forest fire. However, additional maneuvers provide a second daily flyover of the forest fire. The additional maneuvering comes at a significant cost in terms of additional fuel, but provides more data collection opportunities. After data are collected, ground stations receive the data for processing. Optimally selecting the ground station locations reduce the number of built ground stations and reduces the data fusion issues. However, the location of the forest fire alters the optimal ground station sites. A two-stage stochastic programming approach optimizes the selection of ground stations to maximize the expected amount of data downloaded from a satellite. The approaches of selecting initial orbits and ground station locations including uncertainty will provide a robust system to reduce the amount of damage caused by forest fires.

International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / Universal acceptance of the Windows NT operating system has made utilization of the personal computer (PC) platform for critical space operations a reality. The software attributes of the operating system allow PC products to attain the reliability necessary for secure control of on-orbit assets. Not only is the software more reliable, it supports better networking interfaces at higher speeds. The software upgrades that the Microsoft Corporation generates on a regular basis allow PCs to offer capabilities previously available only with UNIX-based solutions. As technology matures, PCs will operate faster, offer more graphical user interfaces, and give customers a lower cost versus performance choice. These reasons, and others to be discussed further, clearly demonstrate that PCs will soon take their place at the forefront of mission-critical ground station applications.

Det är mycket dyrt att utveckla markinfrastruktur för att försörja hela jorden med internet. Detta ärspeciellt fallet i glesbebyggda områden då det finns lite ekonomisk vinning. Sverige som är ett stortoch glesbefolkat land har stora områden av denna typ. Samtidigt är Sverige ett högteknologiskt landdär en stor majoritet av befolkningen använder internet och mobiltelefoni dagligen. Det skapar ettdilemma som är mycket kostsamt att lösa med markbunden teknologi.Sveriges regering samarbetar med teleoperatörer. De köper licenser på auktion för att få användaradiospektrum inom Sverige vilket är en begränsad resurs. I utbyte måste de uppnå vissa täcknings-krav. Dessa teleoperatörer åläggs därmed att täcka Sveriges yt a med potentiell uppkoppling och mo-bilt internet och ingår i ett avtal med regeringen för att få verka.Det är däremot inte särskilt ekonomiskt att göra detta på landsbygden där det bor få människor ochnyttjande av individuella markstationer blir mycket låg. Detta leder då till att dessa master är mycketolönsamma och det är dessutom ett slöseri med resurse r såsom mark, område, natur, material ochpengar. Företag är därför beredda att spendera stora mängder pengar på att undvika att belastas medkrav från Sveriges regering för att utföra detta.Samtidigt är satellitinternet på frammarsch och fler och fler personer världen över införskaffar inter-net via satellit. Detta har blivit ett alternativ.Mycket trådlös teknologi använder specifika olika radiofrekvenser för att överföra information. Dennya typen av satellitinternet använder generellt radiofrekvenser i de så kallade Ku - och Ka-bandenvilka påverkas av vatten. Detta innebär till exempel att regn eller snö ger viss påverkan på kvalitén avden trådlösa förbindelsen.En fråga som bör utredas är hur satellitinternet jämför sig med existerande tekniker som 4G och 5G.På detta sätt kan man uppskatta deras användbarhet.Detta examensarbete fokuserar på att hjälpa till att samla in kunskap i den frågan. För att åstad-komma detta, har det utförts prestandamätningar på relevanta faktorer av en tjänst som tillhanda-håller satellitinternet. Starlink, som är den mest utvecklade s atellitinternettjänsten är föremål fördessa mätningar. Resultatet har blivit mätningar av Starlinks prestanda samt jämförelser mellan4G/5G och Starlink som förhoppningsvis kan belysa Starlinks användbarhet i Norden.Mätningarna indikerar att Starlink har god tillförlitlighet som är jämförbar med mobilnät men i Sve-rige har Starlink onödig fördröjning på cirka 20 millisekunder på grund av att markstationerna ärbelägna i Centraleuropa. / It is very expensive to develop ground-based infrastructure to supply the entire earth with internet.This is especially the case in loosely populated areas where the economic incentive is very low for acompany. Sweden which is a large country with a small population has many areas in this category.At the same time, Sweden is a technologically advanced nation where most people use the internetand mobile telephony daily.The Swedish government cooperates with teleoperators. These teleoperators buy licenses on auctionto be able to use radio spectrum within Sweden which is a limited resource. In exchange they need tofulfill certain quotas on reception and wireless service. The operators are in this way obligated by theSwedish government to supply the country with the potential for reception .However, this is not very economic in rural areas where few people live, and the usage of individualground stations is low. This leads to ground stations being very unprofitable and is also a waste ofresources such as land, materials and capital. Companies are willing to spend large sums of money toavoid obligation to do this.At the same time satellite internet is becoming increasingly sophisticated and more and more peopleworldwide are starting to adopt satellite internet.A lot of wireless technology uses specific different radio frequencies to transmit information. The newtype of satellite internet generally uses frequencies within the Ku - and Ka-bands which are both af-fected by water. This means that for example, rain or snow could affect the quality of the wirelessconnection.A question that should be discussed is how satellite internet compares to existing technologies like4G and 5G. If this is done, it will be easier for involved parties to estimate its usefulness.This bachelor’s thesis focuses on gathering information to help resolve the question of how usefulsatellite internet can be. To accomplish this, performance measurements have been performed on aservice that provides satellite internet. Starlink, which is the most deployed satellite internet service,has been the subject of these measurements. The result is measurements on the performance of Star-link and comparisons between 4G/5G and Starlinks that can hopefully help shed some light on Star-links usefulness in Scandinavia.The measurements indicate that Starlink delivers a reliable connection that can be compared to mo-bile service but that in Sweden there is an added delay of circa 20 milliseconds due to the groundstations being located in central Europe.

International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / Current changes in the way that large flight test systems are utilized have affected the industry’s methodology in both the early design phases and in the implementation of nextgeneration hardware and software. The reduction of available RF spectrum, the implementation of packet telemetry methods and systems, and a desire to implement commercial-off-the-shelf (COTS) hardware are only some of the considerations that telemetry systems integrators and product houses have to face. This paper describes how test methodology changes affect current large systems design at both government test ranges and at airframe/missile manufacturer test facilities. In addition, consideration is given to the area of increased processing power as it affects hardware and software design, the leveraging of such current and future telecommunications technology as network switch technology and compression, cross utilization, standardized technology, and the movement toward platform-independent software.