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Transformational communications architecture for the Unit Operations Center (UOC), Common Aviation Command and Control System (CAC2S), and Command and Control On-the-Move Network, Digital Over-the-Horizon Relay (CoNDOR)Joseforsky, David C., Garcia, Gilbert O. 06 1900 (has links)
Approved for public release, distribution is unlimited / The purpose of this research was to introduce a Transformational Communications Architecture for the Unit Operations Center (UOC); Common Aviation Command and Control System (CAC2S); and Command and Control On-the- Move Network, Digital Over-the-Horizon Relay (CoNDOR). The methodology used was to conduct Field Tests with government contractors and private vendors in order to demonstrate the capabilities of each wireless technology researched. These wireless technologies, Free Space Optics (FSO), Microwave, 802.16, 802.11b over SecNet-11, Orthogonal Frequency Division Multiplexing (OFDM), Broadband Satellite, INMARSAT, and Iridium, all have the potential of being implemented in the transformational communications architecture for intra-nodal and inter-nodal links for UOC and CAC2S, as well as the CoNDOR communications architecture. The ultimate goal of this research was to introduce different technologies that offer more flexibility, mobility, and capability at the tactical level giving the Marine Corps the tactical wireless edge. Throughout this research, the focus revolved around testing equipment and network configurations in an IP network. Special consideration was given to wireless issues for the UOC, CAC2S, and CoNDOR, which could improve line-of-sight, beyond line-of-sight, and over-the-horizon communications for each program. These new technologies will transform communications in the United States Marine Corps for the 21st century. / Captain, United States Marine Corps
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Design and Evaluation of V/UHF Satellite Communication Antennas for Naval ApplicationsBäckström, Hampus January 2018 (has links)
In this master thesis, compact antenna design aimed towards naval applicationshave been designed, analyzed and evaluated. There is a recentinterest in the development of compact antennas to be used for smallersubmarine models, and with a smaller hull on a submarine, communicationand antenna systems must be adapted and minimized, which limitsantenna design. With two limiting cylindrical volumes with maximumallowed dimensions r = 10 cm, h = 50 cm and r = 5 cm, h = 90 cm,the antennas would operate on the upper to lower V/UHF band, radiatehemispherically and have a high RHCP purity. It was found that the mostappropriate antenna structure for both volumes was QHA design. Afterthe design and analysis process was completed, it was concluded that theshorter antenna design could meet all requirements set while the longerantenna design did not meet all requirements but could still establish agood communication link on the higher frequencies. Antenna prototypesbased on the produced design were constructed and measured and, despiteminor deviations, veried that the results obtained from this thesis werereliable. / I denna mastersuppsatsen har kompakta antenner riktade mot marinaapplikationer designats, analyserats och utvarderats. Det nns ett intressefor utvecklingen av kompakta antenner som ska anvandas for mindreubatsmodeller och med ett mindre skrov pa en ubat maste kommunikationsochantennsystemen anpassas och minimeras darefter, vilket begransarantenndesignen. Med tva begransande cylindriska volymer med maximalttillatna dimensioner r = 10 cm, h = 50 cm samt r = 5 cm,h = 90 cm, skulle antennerna verka pa det ovre till lagre V/UHF-bandet,strala hemisfariskt och ha en hog RHCP-renhet. Det konstaterades attden lampligaste antennstrukturen for bada volymen var QHA-design. Efteratt design- och analysprocessen slutforts drogs slutsatsen att den kortareantenndesignen kunde uppfylla alla krav som stalldes medan den langreantenndesignen inte uppfyllde alla krav men fortfarande kunde upprattaen bra kommunikationslank pa de hogre frekvenserna. Antennprototyperbaserade pa de framtagna designerna konstruerades och mattes och, trotsmindre avvikelser, verierade att de erhallna resultaten fran denna avhandlingvar tillforlitliga.
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Commande innovante d’une nouvelle génération d’antenne satellite mobile / New control algorithm for Satcom on the moveBroussard, Elliot 30 November 2018 (has links)
Les systèmes de communication prennent de nos jours une importance de plus en plus prépondérante dans tous les aspects de la vie courante et les exigences de connectivité se retrouvent dorénavant dans de très nombreux projets. Ces besoins de connexion exigent des débits de communication ainsi que des taux de couverture de plus en plus importants, poussant de ce fait vers l’utilisation de systèmes de communication par satellite (SATCOM). Les applications envisagées n’étant pas limitées à des installations fixes, celles-ci demandent de pouvoir assurer une communication par satellite depuis un porteur en mouvement. Il est donc nécessaire d’utiliser des servomécanismes de positionnement de l’antenne de façon à assurer un pointage correct de l’antenne vers le satellite. Ces positionneurs sont donc asservis de façon à orienter la ligne de visée de l’antenne vers le satellite, avec une erreur angulaire de l’ordre du dixième de degré. Cette précision a pour conséquences certaines exigences fortes sur la conception. Ces contraintes imposent l’utilisation de composants de qualité supérieure, des études mécaniques poussées ainsi que des réglages propres à chaque positionneur après assemblage. Dans le cadre de ces travaux de thèse, une stratégie de pointage différente de l’état de l’art a été conçue. Cette stratégie, nommée Helios (Hybrid Estimator of Line Of Sight), permet de lever certains verrous scientifiques spécifiques. Notamment, elle permet une diminution des performances requises de l’asservissement en position de l’antenne en fournissant une trajectoire plus facile à suivre. Cela permet une diminution des contraintes de conception, notamment mécaniques (frottements, raideurs …). Cela est rendu possible par une meilleure estimation de la direction à pointer, utilisant un plus grand nombre de mesures, sans introduire de retard dans l’estimation. Les moyens d’essais de Thales ont permis d’effectuer des essais expérimentaux sur des prototypes industriels. Ainsi, la stratégie est testée en simulation et en expérimentation sur un hexapode simulant un porteur, permettant un recalage du modèle de simulation à partir de données expérimentales. C’est ainsi que la stratégie est validée en conditions opérationnelles. Afin de réaliser ces tests expérimentaux, une étape de mise en place du moyen d’essais a été réalisée. Notamment, les outils de communication ont été mis au point (bus de terrains, liaisons série …). L’asservissement en position de la station a été réalisé à partir d’une identification non-paramétrique en boucle fermée du mécanisme. L’intégration de la station complète a été réalisée, permettant ainsi les tests en extérieur, sur un hexapode. / In military and civil application, satellite communications (SACTOM) are often needed on moving vehicles (drones, planes, land vehicles, vessels…) in order to transfer all kind of data (pictures, videos, internet …). These types of stations are called SATCOM On The Move (SOTM). In order insure high data rates, the antenna must be directional, which means that they direct electro-magnetic waves in a particular direction of space, called line of sight. The line of sight must be steered in order to be aligned with the satellite to insure a strong communication link with the highest data rate possible. Stabilized platforms, called Antenna Positioning System, aim to steer the antenna’s line of sight in the satellite direction. The pointing requirements are the source of conception constraints that reduce the cost efficiency of the overall station. This PhD report focus on the development and the study of a new pointing strategy called Helios (“Hybrid Estimator of LIne Of Sight”). This algorithm uses least squares to found the antenna pattern in real time, using an observation window. Among others, it allows to reduce the bandwidth of the control loops by generating a trajectory easier to follow. Therefore, it decreases the conception constraints (friction, backlash, field bus data rate …). Helios is tested through experimentation, using Thales industrial prototypes. The vehicle is emulated by a hexapod. Simulation is carried out in order to fit the measured experimental behavior. To do so, parametrical and non-parametrical identification has been done on the SOTM prototype. This way, Helios is validated and studied in operational conditions.
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Comparing Control Strategies fora Satcom on the Move Antenna / Jämförelse av reglerstrategier för stabilisering av antenn i mobil satellittjänstHellberg, Joakim, Sundkvist, Axel January 2020 (has links)
Satellite communication is a widely known method for communicating with remote or disaster-strickenplaces. Sometimes, thecommunication can be a matter of life and death,and it is thus vital that it works well. For two-way communication (such as internet) it is necessary for the antenna on Earth to point towards the satellite with a pointing error not larger than a few tenths of a degree. For example, regulations decided by the authorities in the U.S. forbid pointing errors larger than 0.5°. In some cases the antenna on Earth has to be moving while satellite communication is maintained. Such cases can be when the antenna is mounted to a vehicle, and the antenna thus has to compensate for the vehicle’s movement in order to point at the satellite. This application of satellite communication is called Satcom on the Move (SOTM). By constructing a Simulink model of an entire SOTM-system, including vehicle dynamics, satellite position, signal behavior, sensors, and actuators, different control strategies can be compared. This thesis compares the performance of an H2- and an LQG-controller for a static initial acquisition case, and a dynamic inertial stabilization case. The static initial acquisition case is performed with a search algorithm (SpiralSearch) aiming to find the satellite signalin the shortest possible time for a given initial pointing error. The dynamic inertial stabilization case is performed by allowing the simulated vehicle to drive in a slalom pattern and over uneven grounds. The controllers are designed based on modern control theory.The conclusion of this thesis is that the H2-controller performs slightly better in the static testcase,whereastheLQG-controller performs slightly better in the dynamic test cases. However, the results are greatly influenced by the tuning of the controllers, meaning that the comparison is not necessarily true for the controllers rather than the tuning parameters. / Satellitkommunikation är en allmänt känd metod för att kommunicera med avlägsna eller katastrofdrabbade platser. Ibland kan kommunikationen vara en fråga om liv och död, och det är därför viktigt att den fungerar bra. För tvåvägskommunikation (som internet) är det nödvändigt att antennen på jorden pekar mot satelliten med ett pekfel som inte är större än några tiondels grader. Exempelvis finns det lagar i USA som förbjuder pekfel större än 0,5°. I vissa fall måste antennen på jorden röra sig medan satellitkommunikation upprätthålls. Sådana fall kan vara när antennen är monterad på ett fordon och antennen således måste kompensera för fordonets rörelse för att peka mot satelliten. Denna applikation av satellitkommunikation kallas Satcom on the Move(SOTM). Genom att konstruera en simulinkmodell av ett fullständigt SOTM-system, inklusive fordonsdynamik, satellitposition, signalbeteende, sensorer och ställdon, kan olika reglerstrategier jämföras. Denna avhandling jämför en H2 - och en LQG-regulator för ett statiskt fall, samt ett dynamiskt fall. Det statiska fallet utförs med en sökalgoritm (spiralsökning) som syftar till att hitta en specifik satellitsignal på kortast möjliga tid för ett givet initialt pekfel. Det dynamiska fallet utförs genom att låta det simulerade fordonet köra i slalommönster och på ojämnt underlag. Regulatorerna är designade baserade på modern kontrollteori. Slutsatsen av denna avhandling är att H2-regulatorn presterar något bättre i det statiska testfallet, medan LQG-regulatorn presterar något bättre i de dynamiska testfallen. Resultaten påverkas emellertid kraftigt av de designade reglerparametrarna, vilket innebär att jämförelsen inte nödvändigtvis är sann för kontrollerna, utan snarare förde specifika reglerparametrarna.
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