HF ionospheric propagation conditions
Investigation of VLF and HF waves showing seismo-ionospheric anomalies induced by the 29 September 2009 Samoa earthquake (=8.1)
... den ionospheric disturbances at day time (Molchanov et ...the propagation conditions of the transmitter signal through the ionosphere, broaden- ing of the spectrum around the transmitter frequency is ...
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Radio Propagation Prediction for HF Communications
... general propagation conditions and particularly the MUF values during the next week period ...long-term ionospheric forecasts with respect to season as well as solar and geomagnetic ...Short-term ...
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Statistical characteristics of medium scale traveling ionospheric disturbances revealed from the Hokkaido East and Ekaterinburg HF radar data
... Although many authors have studied the MSTID phe- nomena, the effect of geomagnetic activity is still un- clear. Our results show that as a response to an increasing AE index, a relative number of the MSTIDs with higher ...
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Mapping ionospheric backscatter measured by the SuperDARN HF radars part 2: Assessing SuperDARN virtual height models
... -hop propagation paths to SPEAR, (270 and 195 km in ...SuperDARN HF rays ...minimum conditions might also be expected to increase the likelihood of the rays penetrating the ionosphere, thus pre- ...
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Developments in HF Propagation Predictions to Support Communications with Aircraft on Trans polar Routes
... of HF ionospheric propagation and absorption conditions that is consistent with measurements made on a number of oblique HF ...weather conditions need to be incorporated into the ...
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HF wave propagation and induced ionospheric turbulence in the magnetic equatorial region
... effects are accurately approximated in the simulations using pseudo spectral methods, in which the formulas (7) and (8) are used to calculate electron and ion Landau damping in Fourier space [cf. Mjølhus et al., 2003]. ...
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Medium scale traveling ionospheric disturbances over Taiwan observed with HF Doppler sounding
... of 140°, is considered the best estimate of the distur- bance’s horizontal propagation parameters. The param- eter uncertainties are determined by calculating the parameters over slightly different time intervals ...
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STUDY OF SPACE WEATHER ON GPS PERFORMANCE AT LOW LATITUDE STATION BHOPAL AND HIGH LATITUDE STATION MAITRI, ANTARCTICA
... concerning ionospheric storms have been published, in which the effects of magnetic storms on TEC are ...The ionospheric disturbances during magnetic storms are generally explained in terms of the ...
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The effect of earth tides as observed in seismo-electromagnetic precursory signals
... lithosphere, ionospheric perturbations as detected by subionospheric VLF/LF propagation, ...VLF/LF propagation anomaly representing the lower ionospheric per- turbation, we have found the ...
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The Design and Implement of Propagation Path Loss Model over Sea Surface under HF
... However, sea-surfaces are changing all the time. Ocean turbulence will alter the local permittivity and permeability of the ocean and change the height and the angle of the reflection surface, which leads to changes of ...
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On the Tempo Spatial Evolution of the Lower Ionospheric Perturbation for the 2016 Kumamoto Earthquakes from Comparisons of VLF Propagation Data Observed at Multiple Stations with Wave Hop Theoretical Computations
... How about the precursors in Figure 3 with shorter propagation paths? It seems to us that there appear clear tendencies of amplitude depletion for all of these paths (JJI-ANA, JJI-IMZ and JJI-TYH). On the top panel ...
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Imitation and Physical Modeling of the Influence of Ice Coating on the Propagation of Location Signals on the Wires of Overhead Transmission Lines
... the propagation of a sounding signal along a line HF section, measurements of attenuation and an additional delay of the sounding signal in the presence of ice coating on the wires of the OHTL physical ...
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The cost impact to Medicare of shifting treatment of worsening heart failure from inpatient to outpatient management settings
... worsening HF from the inpatient hospital set- ting to OP settings, our assumptions for the proportion of worsening HF admissions to target and the proportion of those targeted that would be successfully ...
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Earthquake forecasting: a possible solution considering the GPS ionospheric delay
... cases, ionospheric activity level increases just before to an earthquake event and shows a different behaviour 5–10 days before the event, when the seismic event has a magnitude greater than ...the ...
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Parallel evolution of circulating FABP4 and NT-proBNP in heart failure patients
... the HF subjects were divided into 3 groups according to the tertiles of 6MWT results, the FABP4 levels were higher in the HF subjects who presented lower results in the 6MWT ...
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Ionospheric electron heating, optical emissions, and striations induced by powerful HF radio waves at high latitudes: Aspect angle dependence
... powerful HF pumping at night in the quiet high- latitude ionosphere have been ...powerful HF pumping show a strong dependence on the angle of the HF pumping waves to the Earth’s magnetic ...of ...
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Propagation of large amplitude ionospheric disturbances with velocity dispersion observed by the SuperDARN Hokkaido radar after the 2011 off the Pacific coast of Tohoku Earthquake
... of propagation velocities have been reported in the results of a numeri- cal simulation by Otsuka et ...main propagation modes discussed by them are the oblique propagation of acoustic waves (770 ...
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Effects of high latitude atmospheric gravity wave disturbances on artificial HF radar backscatter
... phase propagation associated with up- going (down-going) ...the ionospheric response to the thermospheric perturbation to determine AGW properties from the “polarisation” infor- mation provided by the ...
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Giant ionospheric disturbances observed with the SuperDARN Hokkaido HF radar and GPS network after the 2011 Tohoku earthquake
... ward propagation (136–343 m/s) of the enhanced echo re- gions caused by northward-propagating AGW that were ex- cited by the earthquake: it is well known that HF radar echo power fluctuates due to focusing ...
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Simulations of ionospheric turbulence produced by HF heating near the upper hybrid layer
... Abstract Heating of the ionosphere by high-frequency (HF), ordinary (O) mode electromagnetic waves can excite magnetic field-aligned density striations, associated with upper and lower hybrid turbulence and ...
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