Download Deployment/Stationkeeping

Total Page:16

File Type:pdf, Size:1020Kb

Download Deployment/Stationkeeping DEPLOYMENT/STATIONKEEPING DYNAMICS OF N BODY ORBITING SAT CONSTELLATION DOWNLOAD FREE BOOK Avaine Strong | 264 pages | 15 Mar 2009 | VDM Verlag | 9783639125559 | English | Germany Deployment/Stationkeeping Dynamics of N Body Orbiting SAT Constellation Montenbruck, M. SpaceX also plans to sell some of the satellites for military, [6] scientific, or exploratory purposes. Product Details. For a better shopping experience, please upgrade now. ReCon simulations: a 3D view; b 2D view. Space-based, spatio-temporal data is now regularly used to remotely measure fresh water elevation [ 3 ], explore potential mineral deposits [ 4 ], monitor changes in land-cover and land-use [ 56 ], to name a few practical applications. Part I: Compatibility and phasing. We'll get a better sense of value of this when satellites have raised orbits and arrays are tracking Deployment/Stationkeeping Dynamics of N Body Orbiting SAT Constellation sun" Tweet — via Twitter. Acknowledgment The authors are very grateful to the associate editor and two anonymous reviewers for their helpful comments and suggestions on revising the manuscript. View author publications. Retrieved 29 Deployment/Stationkeeping Dynamics of N Body Orbiting SAT Constellation Holdaway R. Retrieved 30 March Spaceflight portal. Definitely peer-to-peer" Tweet. SpaceX intends to provide satellite internet connectivity to underserved areas of the planet, as well as provide competitively priced service to urban areas. Finally, non-penalized J is also a weighted sum of several figures of merit, as shown in Equation 3. However, as those of skill in the art will appreciate, the customer requirements for selected coverage elevation angles to selected geographical areas of the Earth will often suggest reasonable inclination ranges to start with. It is thus shown that the performance-to-cost mass analysis favors a ReCon over a satellite constellation. Minimum and maximum altitude boundaries define design space where Earth-observing satellite can safely operate without suffering excessive atmospheric drag or radiation. The satellites share the responsibility for maintaining good coverage by keeping the elevation angle above the minimum allowable at all times during the mission life of the constellation. In the last decades, a great number of studies have been carried out on libration points and LPOs regarding dynamics, reaching trajectories and required station keeping. For example, crop classification and growth monitoring may be routinely performed on pre-designated areas [ 1112 ], whereas the time and location of flooding or drought cannot be accurately predicted and requires contingent responses. Knowing what typical the characteristics of GPS requirements are, it has been possible to realize a simplified analysis based on GPS-like requirements, such as:. Retrieved 31 March In ReCon, five factors were Deployment/Stationkeeping Dynamics of N Body Orbiting SAT Constellation because the sixth variable, propellant type, had been fixed as a monopropellant. The constraints to be satisfied by the optimal solution are the customer ground coverage requirements, which typically take the form of a minimum elevation line-of-sight angle to one or more satellites in the constellation for some range of ground latitudes and longitudes. On 17 AprilSpaceX modified the architecture of the Starlink network. Latin hypercube sampling LHS is a technique that can reduce the number of sampling while maintaining overall coverage. Macdonald et al. This article is about the SpaceX satellite constellation. Among four figures of merit, only reconfiguration time, as will be discussed in Section 2. A potential region of interest latitude band in this case should be sufficiently observed by maximizing the temporal coverage in GOM, and an outstanding target within that region, once identified, must be visited as frequently as possible by minimizing the revisit time in ROM. Space Res. Ballard A. Temporarily Deployment/Stationkeeping Dynamics of N Body Orbiting SAT Constellation of Stock Online Please check back later for updated availability. Wertz J. Springer, New York, Nonlinear Dynamics of a Two-Chain, Three-Body Formation System Cheng, Y. About this article. Note that the satellite is moving along solid Deployment/Stationkeeping Dynamics of N Body Orbiting SAT Constellation from left to right in prograde orbits this case and vice versa in retrograde orbits. Retrieved 6 October The company has stated that the positive cash flow from selling satellite internet services would be necessary to fund their Mars plans. The time derivatives of the satellite speed and the orbit orientation are used to define the repeat ground track RGT ratio, as shown in Equation A1. Different from only five libration points solved from the circular restricted three-body system, there exist sixteen equilibria for the chain system yielded by its geometry of the pseudo- potential function. However, it is important to note that these trajectories act only as a starting point to find a proper solution to the problem: the satellites Deployment/Stationkeeping Dynamics of N Body Orbiting SAT Constellation not constrained to follow any halo orbit, rather they must satisfy well-defined mission requirements, as already stated. LHS divides the design space into l divisions levels of value for each of n factors variablescombining them randomly. Draim; and, Deployment/Stationkeeping Dynamics of N Body Orbiting SAT Constellation. This book sheds light on recent advances in the field of astronautical sciences and should prove useful for the practicing professional or for conducting research in spaceflight mechanics. The empirical relationship between m tank and m p are given in Equations 14 and 15 for two propellant types, cold gas and monopropellant respectively. Figure 4. The initial conditions used to start the optimization process have been selected to have an even distribution of the satellites along the reference orbit, i. Brill Publishers; Leiden, The Netherlands: The two methods have widely been used in solving NP-hard combinatorial problems [ 3233 ] to benchmark each other, sometimes forming hybrids to complement one another [ 3435 ]. In addition to the heuristic algorithm, ReCon optimization was also attempted using gradient-based methods. The KH keyhole satellites consisted of five satellites allocated to two planes, all of which were highly maneuverable for reconnaissance purposes [ 18 ]. A method for establishing an initial inclination and right ascension of the ascending node RAAN of the orbits of each satellite of a constellation of Earth orbiting satellites in such a way that, over a specified operational life of the constellation, the associated inclination and RAAN values for each satellite can be allowed to drift in response to perturbative gravitational accelerations acting on the satellites while maintaining a required minimum line of sight elevation angle MLOSEA between a selected geographical area of Deployment/Stationkeeping Dynamics of N Body Orbiting SAT Constellation surface of the Earth and at least one satellite of the constellation and using a minimal amount of satellite propellant to effect out-of-plane control of the satellites, the method comprising: providing an initial value of the inclination and RAAN of each of the orbits of each of the satellites adapted to effect maintenance of the required MLOSEA. Such authority would enable SpaceX to obtain critical data regarding the operational performance of these user terminals and the SpaceX NGSO system This article incorporates text from this source, which is in the public domain. For this simple case, it may be seen that either of the two satellite's initial RAAN must be adjusted by half of the maximum deviation as illustrated in FIG. Multiple constraints are expressed as a vector hand the objective F is scalar. Celestri Teledesic. These two are a good starting point before transitioning to multiple-objective optimization or other state-of-the-art methods in future work [ 3637 ]. The lower orbit also means more distance between Starlink and competing Deployment/Stationkeeping Dynamics of N Body Orbiting SAT Constellation constellations proposed by OneWeb and Telesat. Temporarily Out of Stock Online Please check back later for updated availability. The Verge. WOA3 en. The schema is a concatenation of binary forms of design variables, which are given a varying number of bits according to their values and required accuracy. Impulsive feedback control to establish specific mean orbit elements of spacecraft formations. The design vector x Section 2. K uK aand E-band phased array antennas Hall-effect thrusters. The invention thus enables a substantial reduction in the amount of propellant that the satellites must carry onboard to maintain good coverage during the life of the constellation. With this initialization, the satellites are thereafter free to drift in both inclination and RAAN throughout their lifetime, and the necessity of maneuvers to control these orbital parameters to maintain good coverage is eliminated or substantially reduced. It is also notable that the exponent value of 0. Connerney et al. Table 7 Inputs and output variables of simulation modules. This book explores the techniques for station keeping an orbiting constellation of satellites in an elliptical orbit after the initial deployment is developed. Figure 2. An exemplary embodiment of an algorithm adapted to compute such a sufficiently close set of initial elements comprises assuming a nominal RAAN separation between
Recommended publications
  • IAC-18-B2.1.7 Page 1 of 16 a Technical Comparison of Three
    A Technical Comparison of Three Low Earth Orbit Satellite Constellation Systems to Provide Global Broadband Inigo del Portilloa,*, Bruce G. Cameronb, Edward F. Crawleyc a Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge 02139, USA, [email protected] b Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge 02139, USA, [email protected] c Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge 02139, USA, [email protected] * Corresponding Author Abstract The idea of providing Internet access from space has made a strong comeback in recent years. After a relatively quiet period following the setbacks suffered by the projects proposed in the 90’s, a new wave of proposals for large constellations of low Earth orbit (LEO) satellites to provide global broadband access emerged between 2014 and 2016. Compared to their predecessors, the main differences of these systems are: increased performance that results from the use of digital communication payloads, advanced modulation schemes, multi-beam antennas, and more sophisticated frequency reuse schemes, as well as the cost reductions from advanced manufacturing processes (such as assembly line, highly automated, and continuous testing) and reduced launch costs. This paper compares three such large LEO satellite constellations, namely SpaceX’s 4,425 satellites Ku-Ka-band system, OneWeb’s 720 satellites Ku-Ka-band system, and Telesat’s 117 satellites Ka-band system. First, we present the system architecture of each of the constellations (as described in their respective FCC filings as of September 2018), highlighting the similarities and differences amongst the three systems.
    [Show full text]
  • Towards 6G Through Sdn and Nfv-Based Solutions for Terrestrial and Non-Terrestrial Networks
    TOWARDS 6G THROUGH SDN AND NFV-BASED SOLUTIONS FOR TERRESTRIAL AND NON-TERRESTRIAL NETWORKS A Dissertation Presented to The Academic Faculty By Ahan Kak In Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the School of Electrical and Computer Engineering Georgia Institute of Technology May 2021 © Ahan Kak 2021 TOWARDS 6G THROUGH SDN AND NFV-BASED SOLUTIONS FOR TERRESTRIAL AND NON-TERRESTRIAL NETWORKS Thesis committee: Dr. Ian F. Akyildiz (Advisor) Dr. Chuanyi Ji School of Electrical and Computer School of Electrical and Computer Engineering (Formerly) Engineering Georgia Institute of Technology Georgia Institute of Technology Dr. Raghupathy Sivakumar (Chair) Dr. Henry L. Owen School of Electrical and Computer School of Electrical and Computer Engineering Engineering Georgia Institute of Technology Georgia Institute of Technology Dr. Mary Ann Weitnauer Dr. Andy Sun School of Electrical and Computer School of Industrial & Systems Engineering Engineering Georgia Institute of Technology Georgia Institute of Technology Date approved: April 6, 2021 To my family, for their endless love, support, and encouragement. ACKNOWLEDGMENTS I would like to begin by expressing my deepest gratitude to my advisor, Dr. Ian F. Aky- ildiz. I am extremely grateful to him for giving me the life-changing opportunity of joining his lab. His unparalleled vision and boundless passion have been integral in setting me on the path to academic success. Like a guiding light that shines through stormy seas, Prof. Akyildiz’s limitless wisdom has always led the way forward, even in the most difficult of times. His incredible work ethic has been a constant source of inspiration for me throughout this journey, one that has been greatly enriched by his immense knowledge and extensive experience.
    [Show full text]
  • Commercial Spacecraft Mission Model Update
    Commercial Space Transportation Advisory Committee (COMSTAC) Report of the COMSTAC Technology & Innovation Working Group Commercial Spacecraft Mission Model Update May 1998 Associate Administrator for Commercial Space Transportation Federal Aviation Administration U.S. Department of Transportation M5528/98ml Printed for DOT/FAA/AST by Rocketdyne Propulsion & Power, Boeing North American, Inc. Report of the COMSTAC Technology & Innovation Working Group COMMERCIAL SPACECRAFT MISSION MODEL UPDATE May 1998 Paul Fuller, Chairman Technology & Innovation Working Group Commercial Space Transportation Advisory Committee (COMSTAC) Associative Administrator for Commercial Space Transportation Federal Aviation Administration U.S. Department of Transportation TABLE OF CONTENTS COMMERCIAL MISSION MODEL UPDATE........................................................................ 1 1. Introduction................................................................................................................ 1 2. 1998 Mission Model Update Methodology.................................................................. 1 3. Conclusions ................................................................................................................ 2 4. Recommendations....................................................................................................... 3 5. References .................................................................................................................. 3 APPENDIX A – 1998 DISCUSSION AND RESULTS........................................................
    [Show full text]
  • Flying Constellations in the Cloud
    SSC17-V-07 Flying Constellations in the Cloud Chris Beam Kratos Technology & Training Solutions, Inc. 980 Technology Court, Colorado Springs, CO 80915; 719-472-3495 [email protected] ABSTRACT The space industry is in the midst of technological upheaval involving the proliferation of small satellites and the commercialization of cloud computing as a service. The proliferation of small satellites is made possible by cube sat standards, normalized small satellites launch vehicles, and continued miniaturization of electronics. The small satellite revolution has created new business, science and defense based opportunities resulting in new proposals for sizeable small satellite constellations. Similarly cloud computing as a service, has made possible the advent of high performance computing platforms and the emergence of commodity virtual machine technology. Hundreds of cloud computing service providers have emerged including Amazon, Microsoft, IBM, and HP. At the convergence of these two technological upheavals is an opportunity, perhaps even a mandate, to transition traditional satellite group processing from dedicated operations centers to cloud computing centers. By utilizing virtual machine technology, Kratos has hosted a software based ground system with a significantly smaller footprint than traditional ground systems. While this is a step in the right direction and works well for a single satellite or small constellation, the reality is a 1,000 constellation of small satellites is very possible in today’s industry and traditional ground processing resources may not be viable solutions. As a research initiative, Kratos used Amazon cloud computing services to simulate the deployment and operations of a large fleet operations center capable of supporting 1,000 spacecraft with 30 simultaneous contacts and 100 users.
    [Show full text]
  • Quarterly Launch Report
    Commercial Space Transportation QUARTERLY LAUNCH REPORT Featuring the launch results from the previous quarter and forecasts for the next two quarters 1st Quarter 1998 U n i t e d S t a t e s D e p a r t m e n t o f T r a n s p o r t a t i o n • F e d e r a l A v i a t i o n A d m i n i s t r a t i o n A s s o c i a t e A d m i n i s t r a t o r f o r C o m m e r c i a l S p a c e T r a n s p o r t a t i o n QUARTERLY LAUNCH REPORT 1 1ST QUARTER 1998 REPORT Objectives This report summarizes recent and scheduled worldwide commercial, civil, and military orbital space launch events. Scheduled launches listed in this report are vehicle/payload combinations that have been identified in open sources, including industry references, company manifests, periodicals, and government documents. Note that such dates are subject to change. This report highlights commercial launch activities, classifying commercial launches as one or more of the following: • Internationally competed launch events (i.e., launch opportunities considered available in principle to competitors in the international launch services market), • Any launches licensed by the Office of the Associate Administrator for Commercial Space Transportation of the Federal Aviation Administration under U.S.
    [Show full text]
  • Dot 12526 DS1.Pdf
    1997 LEO COMMERCIAL MARKET PROJECTIONS EXECUTIVE SUMMARY PROJECTED SATELLITE DEMAND Based on the information provided in this report, the Federal Aviation Administration’s Associate Administrator for Commercial Space Transportation (AST) has developed two scenarios describing LEO satellite and launch services demand in the 1997 to 2006 time frame: a “modest growth” scenario and a “high growth” scenario. This approach is similar to the one used to prepare the 1996 LEO Commercial Market Projections report. The modest growth scenario is based on relatively conservative assumptions regarding market demand and is considered to be more likely than the high growth scenario. · Modest Growth: AST projects that four big LEO (including MEO) and two little LEO systems will be deployed from 1997 to 2006. · High Growth: AST projects that five big LEO systems, one broadband LEO (formerly referred to as a “mega” LEO), and three little LEOs will be deployed from 1997 to 2006. It appears that demand in the commercial remote sensing market will be capable of supporting as many as four of the proposed ventures to provide commercial high-resolution imagery (containing between one and four satellites each). Thus, commercial remote sensing ventures — along with a steady requirement for commercial launch of scientific and microgravity payloads — could represent a secondary source of demand for LEO satellites and launches. PROJECTED LAUNCH DEMAND Based on AST’s satellite demand projections, the demand for commercial launches to LEO for the “modest growth” scenario should be 9 to 14 annual medium-to-large-class launches (payloads greater than 10,000 lbs.) through the year 2000, decreasing to 2 to 4 launches per year from 2001 to 2002, surging to 11 to 14 per year in 2003 to 2004, and dropping to 4 to 6 per year for the remainder of the forecast period.
    [Show full text]
  • International Space Law”
    ST/SPACE/2 Office for Outer Space Affairs United Nations Office at Vienna Proceedings of the Workshop on Space Law in the Twenty-first Century Organized by the International Institute of Space Law with the United Nations Office for Outer Space Affairs UNITED NATIONS New York, 2000 This document has not been formally edited. Introduction The Workshop on Space Law in the 21st Century, coordinated by the International Institute of Space Law (IISL), was held between 20 and 23 July 1999 in Vienna, Austria, as part o f the Third United Nations Conference on the Exploration and Peaceful Uses of Outer Space (UNISPACE III). More than 120 participants attended the Workshop, all contributing to an active discussion on the future of Space Law. The IISL Workshop comprised eight sessions, covering current concerns in the field of space law. Each session began with the presentation of a discussion paper by an invited speaker, followed by invited papers commenting on the discussion paper, as well as informal discussion and comments. At the end of each session, the Coordinator/Rapporteur of the session presented a summary report on significant issues raised in the session and, following a general discussion, the findings, conclusions and recommendations of the session were consolidated in a single document. At the conclusion of the eight substantive sessions, the “Workshop Executive Committee”, consisting of the chairperson of each session, the Workshop Coordinator, and the President of the International Institute of Space Law, who was the overall chairperson of the Workshop, met to discuss the reports of the sessions. The session reports were integrated into the Workshop’s Final Report to the UNISPACE III Conference.
    [Show full text]
  • Descripción De La Red Satelital O3b Y Aproximación Del Comportamiento Para Uso De Un Terminal Genérico En Poblaciones Rurales Del Ecuador
    Universidad Politécnica de Madrid Escuela Técnica Superior de Ingenieros de Telecomunicación DESCRIPCIÓN DE LA RED SATELITAL O3B Y APROXIMACIÓN DEL COMPORTAMIENTO PARA USO DE UN TERMINAL GENÉRICO EN POBLACIONES RURALES DEL ECUADOR TRABAJO FIN DE MÁSTER Nelson Fernando Vinueza Escobar 2015 Universidad Politécnica de Madrid Escuela Técnica Superior de Ingenieros de Telecomunicación Máster Universitario en Ingeniería de Redes y Servicios Telemáticos TRABAJO FIN DE MÁSTER DESCRIPCIÓN DE LA RED SATELITAL O3B Y APROXIMACIÓN DEL COMPORTAMIENTO PARA USO DE UN TERMINAL GENÉRICO EN POBLACIONES RURALES DEL ECUADOR Autor Nelson Fernando Vinueza Escobar Director Carlos Miguel Nieto Departamento de Ingeniería de Sistemas Telemáticos 2015 Resumen La creciente demanda de conectividad a Internet junto con la carencia de disponibilidad de acceso a banda ancha desde lugares remotos o poco atractivos para los proveedores tradicionales, ha impulsado la aparición de proveedores de servicio satelital con nuevas propuestas de sistemas satelitales MEO de alto rendimiento tipo (HTS), de bajo retardo respecto a los tradicionales sistemas GEO, como es el caso del sistema satelital denominado O3b. El presente trabajo describe el funcionamiento del sistema O3b con el fin de entender las características principales asociadas a la prestación de servicios fijos por satélite (FSS) específicamente para Ecuador, considerando el uso de la Banda Ka y la degradación que sufren los enlaces frente a condiciones de lluvia en especial en zonas de clima tropical, para lo que se han seleccionado un conjunto de ubicaciones a lo largo de las diferentes regiones del país. Inicialmente, se realiza una descripción general de los sistemas de comunicación por satélite con los principales conceptos a utilizar en el desarrollo del presente trabajo, profundizando en las características y comportamiento y estado del arte del sistema satelital O3b.
    [Show full text]
  • Tr 101 374-01
    TR 101 374-1 V1.2.1 (1998-10) Technical Report Satellite Earth Stations and Systems (SES); Broadband satellite multimedia; Part 1: Survey on standardization objectives 2 TR 101 374-1 V1.2.1 (1998-10) Reference DTR/SES-00038-1 (cq090ios.PDF) Keywords broadband, satellite, earth station, multimedia ETSI Postal address F-06921 Sophia Antipolis Cedex - FRANCE Office address 650 Route des Lucioles - Sophia Antipolis Valbonne - FRANCE Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Siret N° 348 623 562 00017 - NAF 742 C Association à but non lucratif enregistrée à la Sous-Préfecture de Grasse (06) N° 7803/88 Internet [email protected] http://www.etsi.org Copyright Notification No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media. © European Telecommunications Standards Institute 1998. All rights reserved. ETSI 3 TR 101 374-1 V1.2.1 (1998-10) Contents Intellectual Property Rights..............................................................................................................................10 Foreword ..........................................................................................................................................................10 1 Scope......................................................................................................................................................11 2 References..............................................................................................................................................11
    [Show full text]
  • The End of Secrecy? Military Competitiveness in the Age of Transparency
    The End of Secrecy? Military Competitiveness in the Age of Transparency Beth M. Kasper, USAF August 2001 Occasional Paper No. 23 Center for Strategy and Technology 23 Air War College Air University Maxwell Air Force Base The End of Secrecy? Military Competitiveness in the Age of Transparency by Beth M. Kaspar, Lt Col USAF August 2001 Occasional Paper No. 23 Center for Strategy and Technology Air War College Air University Maxwell AFB, AL The End of Secrecy? Military Competitiveness in the Age if Transparency Beth M. Kaspar, Lt Col USAF August 2001 The Occasional Papers series was established by the Center for Strategy and Technology as a forum for research on topics that reflect long-term strategic thinking about technology and its implications for U.S. national security. Copies of No. 23 in this series are available from the Center for Strategy and Technology, Air War College, 325 Chennault Circle, Maxwell AFB, AL 36112. The phone number is (334) 953-6150. Occasional Paper No. 23 Center for Strategy and Technology Air War College Air University Maxwell Air Force Base, Alabama 36112 Contents Page Disclaimer .................................................................................................... i About The Author ....................................................................................... ii Preface........................................................................................................iii Abstract .....................................................................................................
    [Show full text]
  • The Impact of Innovation in the Satellite Industry on the Telecommunications Services Market
    BULGARIAN ACADEMY OF SCIENCES PROBLEMS OF ENGINEERING CYBERNETICS AND ROBOTICS • 2020 • Vol. 73, pp. 30-38 p-ISSN: 2738-7356; e-ISSN: 2738-7364 https://doi.org/10.7546/PECR.73.20.03 The Impact of Innovation in the Satellite Industry on the Telecommunications Services Market Krasimir Terziev1, Dimitar Karastoyanov1 1 Institute of Information and Communication Technologies, Sofia, Bulgaria Emails: [email protected], [email protected] Abstract: The article analyses the role of the satellites in global communications. Different types of orbits and different types of satellites are described. The commercial start of low and medium orbit satellites is considered. The integration of some Low Earth Orbit (LEO) projects with Teleports is commented. Some significant LEO/MEO (Medium Earth Orbit) projects are cited. The impact of the satellite industry and the Teleport systems on the technological ecosystem is discussed. LEO satellites for monitoring the earth's surface are presented. Keywords: LEO, Orbit, Satellite, Teleport. 1. Introduction Satellite connections and networks play an important role in global communications, [1]. They are part of the global telecommunications network [2]. Their indisputable advantage is that they provide instant communication to the most remote and inaccessible places (no need to build cable infrastructure, but only one receiving and/or transmitting antenna), are not affected by natural disasters on the earth’s surface (earthquakes, floods and others), provide connections and internet to the seas and oceans (standard cable networks cannot connect sea-going vessels). Telecommunication networks could be modelled by separate graph models that already exist. Using the unified model makes it possible to solve new classes of problems that cannot be solved using traditional systems [3], [4].
    [Show full text]
  • Modeling and Routing for Predictable Dynamic Networks: This Paper Is
    Modeling and Routing for Predictable Dynamic Networks This paper is only for copyright protection, and unpublished to the top-level version. Zengyin Yang, Qian Wu, Hewu Li, Zhize Li and Jianping Wu, Fellow IEEE Tsinghua University, Beijing, China f yang-zy14, zz-Li14 [email protected], f wuqian, lihewu, jianping [email protected] Abstract—Currently, building a Satellite-Based Internet (SBI) permanently fly along some fixed orbits from a polar to providing global Internet service has become a trend, and other. As satellite routers are extremely far away from each the Iridium-like constellation is considered as the promising other, the propagation delay of link is so large that is in topology. However, such topology is dynamic in terms of node most cases taken as the link metric for routing selection position, network connectivity and link metric, which lead to algorithm [8–12]. drastic end-to-end path changes in polar region and overly Actually, the Iridium-like constellation topology is dy- frequent routing updates. In this paper, we propose a link namic. The link metric and network connectivity continu- lifetime assisted routing (LLAR) scheme that incorporates life- ously changes with the position of routers, which brings time of links into their metrics to solve the routing oscillation great challenges for SBI to achieve routing stability. The in polar region. However, it is unpractical to implement the main problems are two-fold. routing scheme into dynamic network directly because these 1) Polar routing oscillation. In polar region, link metric dynamics will require routing to be updated continuously and link connectivity are conflicted.
    [Show full text]