PowerPoint Presentation

Beacon Satellite ScintillationSputnik to Cubesat

Charles RinoVisiting Scholar, Boston College, Institute for Scientific Research2013 Beacon Satellite Symposium

8-12 July 2013Bath, UK1

Van Goghs Starry Night from a paper of the same name by M. Colleen Ginohttp://www.astrophys-assist.com/educate/starry/starrynight.htm2

James Clerk Maxwell Statue commissioned in 2006 to celebrate the 175th anniversary of his birthUnveiled in 2008

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The Technical Legacy of World War IIRadarRemote sensing, automated fire control, cyberneticsElectronic IntelligenceElectronic computers, information theory, and artificial intelligenceRocketryBeacon satellites and space explorationNuclear WeaponsExistential threat that profoundly influenced the pace of technology development4

Vannevar BushScientist Visionary 1890-1974Directed OSRD from 1941 to 1947Worked for establishment of government agencies to foster the development of WW II technologyInstrumental in establishing the National Science Foundation in 1950Dwight Eisenhowers election in 1952 began a period of resistance to big government programs His differential analyzer usedduring WW II to calculatefiring tables for large guns5

SPUTNIK 4 October 19576

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Within a year of the launch of Sputnik Iboth the National Space and Aeronautics Association (NASA) and the Advanced ResearchProjects Agency (ARPA) were established SputnikRadio amateurs around the world detected Sputniks 20 and 40 MHz Beacon signals

Scientists at the Johns Hopkins Applied Physics Laboratory (APL) were tasked with determining Sputniks orbitBy observing Sputniks Doppler shift from a know location the orbit could beprecisely determined. APL scientists realized that if the satellite could broadcast its position to an observer, the process could be reversed to determine the observers location.7

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Navy Navigation Satellite SystemTRANSITSCOUT-DWithin a decade of Sputnik I satellite navigation using VHF-UHF beacons was realized (1964)

Rapid development was stimulated by Polaris submarine positioning requirements for launching nuclear missiles The robust solar-powered transit satellites and the Scout-D launch vehicles were so reliable that an large excess inventory developed 8

Phase ScreenWidebandIn the late 1960s Stanford Research Institute (now SRI International) developed a multi-frequency satellite beacon and receiver system for the Defense Nuclear Agency (DNA)The objective was to measure UHF frequency coherence under highly disturbed conditionsIn 1975 an attempted Wideband launch as a secondary Air-Force satellite payload failed A year later a TRANSIT spare carried the DNA Wideband satellite into a sun-synchronous polar orbitWideband operated for nearly 5 years before the data collection sites were shut down. The beacon functioned for at least a decade9

Scintillation Road Map

MOMENTEQUATIONS&PATHINTEGRALSFIELDREALIZATIONSDIRECTINTEGRATIONPARABOLICAPPROXIMATIONCOHERENCEMEASURESPROBABILISTICMODELSPDFS 3D2DEQUIVALETPHASE SCREEN16

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Modern Beacon Satellites GPS COSMICOperational 2006 CUBESAT First launched 2003 Operational199411

Two Scintillation PioneersHenry Booker1910-1988Jules Aarons1921-2008Henry BookerCambridge University degrees in pure and applied mathematics and ionospheric physicsLecturer at Cambridge working under J. A. Radcliffe 1933 to 1948Cornell University from 1948 to 1965Students: Ken Bowles, Don Farley, and William GordonFounded the U.C.S.D Department of Applied Electrophysics in 1965, now the Jacobs School of EngineeringFaculty: Jules Fejer, Peter Banks, Irwin Jacobs, Marshall Cohen, Victor Rumsey, and Ian Axford, and Hanes Alfvein (Visiting)

Jules AaronsGraduated from City College of NY in 1942 Fulbright Scholar Ph. D University of Paris 19541943 -1945 Army Air Force Radio and Radar Officer1946-1981 AFGL1981-2005 Professor of Astronomy and Space Physics Boston UniversityStimulated DOD scintillation research using radio astronomy well before SputnikStimulated international cooperative scintillation research leading to the morphology of scintillation and its relation to global ionospheric dynamicsThe Beacon Satellite Symposia can be thought of as one of his legacies

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SOURCEOBSERVATIONPLANESTRUCTUREDMEDIUMAbstracting The Problem3D2D1D Scan13

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Why So Difficult?

According to MaxwellBorn Approximation

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Phase ScreenCalculation of field moments involves the expectation of products of fields and the refractive index variationWell before Sputnik it was known that Russian researchers had mastered this computationTranslations of Tatarskis seminal book and numerous papers by Russian scientists were widely circulated in the 1960s. The 1971 review paper by Barabanenkov summarized this workA key result was a hierarchy of first-order differential equations of increasing complexity that characterize the complex field momentsIn spite of the cold war, an active period of U.S.S.R - U.S. exchange and collaboration followedThe Heyday of Scintillation1970-2000URSI USSR meeting held at Yakov Alperts IZMIRAN laboratory November 1974Early results from ATS 6 were reportedSeptember 1988 workshop Tallin, Estonia organized by Professors Tatarski and IshimaruInitiated collaborations and friendships that have persisted to this dayAn outgrowth was a week-long meeting held at the University of Washington in 1992. The published collection of invited papers edited by Tatarski, Ishimaru, and Zavronity is the finest compendium of propagation in random media available1982 review papers by Yeh & Liu and Aarons, Special issues of Radio Science (Jan., 1975), JOSA (Dec.,1985), and a new journal, Waves in Random Media (1991) were dedicated to the subject

Archived material kindly recovered by Valery Zavrotny and Akira Ishimaru15

Phase ScreenMissing ColleaguesKung Chie Yeh (1992)1982 Review Paper with Chao Han LiuRoger Dashen (1995) & Stanley Flatte (2007)Ocean AcousticsSantimay Basu (2013) AE-E and Original work with Emanuel Costa17

Phase ScreenCanonical Example

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Phase ScreenExtreme Scintillation

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Phase ScreenLooking AheadGPS Beacons together satellite and ground-based diagnostics have revolutionized the study of the near-earth environmentPath-integrated phase interpreted as TEC is a primary inputSophisticated analysis procedures are seamlessly integrating physics-based models and very large data bases with improving resolution

Propagation analysis should be brought into the same frameworkThis will require a rethinking of structure formation and the development of new structure models to accommodate the inhomogeneous anisotropic structure that causes scintillation and ultimately limits the performance and utility of GPSThe last paper of the session will discuss iterative parameter estimation as a tool for exploiting strong scatter at L-band

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Thank You

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