Docstoc

trt02_eccles

Document Sample
trt02_eccles Powered By Docstoc
					Investigation and Development of Data-Driven
  D-Region Model for HF Systems Impacts
                           D. Rice
          Space Environment Corp., Providence, Utah

                     R. D. Hunsucker
             RP Consultants, Klamath Falls, Oregon

                          J. Eccles
          Space Environment Corp., Providence, Utah

                         J. J. Sojka
          Space Environment Corp., Providence, Utah

             NASA - Living With A Star
      (from material presented at Spring AGU/Montreal)

   Space Environment Corporation                         1
    Investigation and Development of Data-Driven
      D-Region Model for HF Systems Impacts
•   Space Environment Corporation              HF Link Monitoring
         •      Vince Eccles                 (www.spacenv.com/~rice/hidive)
         •      Bob Hunsucker
         •      Don Rice
         •      Jan Sojka

•   Developing a Data-Driven D-Region
    model for real-time HF absorption
    calculations with validation obtained
    from a low-cost HF-link monitoring
    network.

•   NASA satellite data streams and HF
    monitoring experiment are used to
    determine D-Region specification
    during solar x-ray flares, particle
    events, winter absorption anomaly,
    sporadic E
             Space Environment Corporation                              2
     HF Propagation and Absorption Modeling



   F-Region



   E-Region
   D-Region




• The Data-Driven D-Region is combined with E and F Region model
  ionosphere (IRI, and others) to provide background for ray-tracing and
  absorption calculations.

• Results compared with HF-link Monitoring Experiments.

              Space Environment Corporation                                3
                 Modeling and Monitoring D-Region Weather
                  UT (hour)                                                                UT (hour)
                                    • Large space weather events are
                                      evident in 2003 data and
                                      model of 5000 kHz HF
                                      propagation characteristics
                                    • Low frequency propagation at
                                      night due to daytime
                                      absorption.
Day of 2003




                                                                         Day of 2003
                                    • Most notably the “Halloween
                                      Storm” in October-November
                                    • Nighttime variations in HF
                                      propagation cutoffs.
                                    • Daytime absorption increases
                                      during winter anomaly events are
                                      easily identified. (Improvements
              Model Signal@KF         of NO model density needed.)                     Measured Signal@KF
               Model Signal@KF
                        Space Environment Corporation                                                  4
              Modeling and Monitoring E&F-Region Weather
                 UT (hour)                                                             UT (hour)
                                   • Space weather observed in
                                     10000 kHz HF propagation
                                     characteristics.
                                   • High frequency propagation
                                     during daytime only
                                     (generally)
Day of 2003




                                                                     Day of 2003
                                   • Solar rotation variation
                                     influence on ionosphere
                                     ionization rates.
                                   • Sporadic E layer provides for
                                     low angle HF propagation
                                     during nighttime…not modeled.
                                   • Diurnal and seasonal trends
                                     captured.
              Model Signal@KF                                                      Measured Signal@KF

                       Space Environment Corporation                                               5

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:0
posted:2/16/2012
language:
pages:5