HR: 16:00h
AN: SA22C-01    [PDF]
TI: GPS Occultation Observations of the Global and Seasonal Distribution of Equatorial Scintillation
AU: Danaher, J E
AF: DSP Max, Inc., 1425 N. Alta Vista Blvd. #221, Los Angeles, CA 90046 United States
AU: * Anderson, P C
EM: phillip.c.anderson@aero.org
AF: The Aerospace Corporation, Box 92957 M2/260, Los Angeles, CA 90009 United States
AU: Straus, P R
EM: paul.r.straus@aero.org
AF: The Aerospace Corporation, Box 92957 M2/260, Los Angeles, CA 90009 United States
AB: We present a globally and seasonally distributed set of observations of radiowave scintillation by GPS occultation sensors on-board the PICOSat, CHAMP, and Sac-C satellites. GPS occultation measurements provide a means of measuring ionospheric scintillation on a global basis, which can not be done using traditional ground-based scintillation monitoring techniques. Strong fluctuations in the GPS C/A code signal-to-noise ratio (SNR) data at the L1 frequency (1.575 GHz) are shown to be indicative of scintillation. The source of the SNR fluctuations is evaluated through a statistical analysis of a full year of occultation data from January - December, 2002. The geographic and local time distributions of occultations having large values of the S4 scintillation index are consistent with known scintillation climatology, unambiguously identifying the fluctuations as ionospheric scintillation. We also show that, given the proper geometry, the occultation technique enable mapping of the vertical distribution of the ionospheric structures (bubbles) responsible for the scintillation.
DE: 2415 Equatorial ionosphere
DE: 2439 Ionospheric irregularities
DE: 6934 Ionospheric propagation (2487)
DE: 6979 Space and satellite communication
SC: SPA - Aeronomy [SA]
MN: 2003 Fall Meeting