Academic literature on the topic 'Ionospheric techniques'
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Journal articles on the topic "Ionospheric techniques"
Walker, I. K., J. A. T. Heaton, L. Kersley, C. N. Mitchell, S. E. Pryse, and M. J. Williams. "EISCAT verification in the development of ionospheric tomography." Annales Geophysicae 14, no. 12 (December 31, 1996): 1413–21. http://dx.doi.org/10.1007/s00585-996-1413-8.
Full textPrajapati, Parinda, and Nimisha Patel. "Ionospheric Model Development for Indian Region: A Survey Paper." ECS Transactions 107, no. 1 (April 24, 2022): 11075–82. http://dx.doi.org/10.1149/10701.11075ecst.
Full textJin, Shuanggen, J. U. Park, J. L. Wang, B. K. Choi, and P. H. Park. "Electron Density Profiles Derived From Ground-Based GPS Observations." Journal of Navigation 59, no. 3 (August 23, 2006): 395–401. http://dx.doi.org/10.1017/s0373463306003821.
Full textBae, Tae-Suk, and Minho Kim. "Performance Analysis of Network-RTK Techniques for Drone Navigation considering Ionospheric Conditions." Journal of Sensors 2018 (2018): 1–8. http://dx.doi.org/10.1155/2018/5154697.
Full textAmm, O., A. Aruliah, S. C. Buchert, R. Fujii, J. W. Gjerloev, A. Ieda, T. Matsuo, C. Stolle, H. Vanhamäki, and A. Yoshikawa. "Towards understanding the electrodynamics of the 3-dimensional high-latitude ionosphere: present and future." Annales Geophysicae 26, no. 12 (December 5, 2008): 3913–32. http://dx.doi.org/10.5194/angeo-26-3913-2008.
Full textHughes, J. M., W. A. Bristow, R. A. Greenwald, and R. J. Barnes. "Determining characteristics of HF communications links using SuperDARN." Annales Geophysicae 20, no. 7 (July 31, 2002): 1023–30. http://dx.doi.org/10.5194/angeo-20-1023-2002.
Full textChan, A. H. Y., and P. S. Cannon. "Nonlinear forecasts of ƒ<i>o</i>F2: variation of model predictive accuracy over time." Annales Geophysicae 20, no. 7 (July 31, 2002): 1031–38. http://dx.doi.org/10.5194/angeo-20-1031-2002.
Full textPimenta, A. A., P. R. Fagundes, Y. Sahai, J. A. Bittencourt, and J. R. Abalde. "Equatorial F-region plasma depletion drifts: latitudinal and seasonal variations." Annales Geophysicae 21, no. 12 (December 31, 2003): 2315–22. http://dx.doi.org/10.5194/angeo-21-2315-2003.
Full textProvan, G., T. K. Yeoman, S. E. Milan, J. M. Ruohoniemi, and R. Barnes. "An assessment of the "map-potential" and "beam-swinging" techniques for measuring the ionospheric convection pattern using data from the SuperDARN radars." Annales Geophysicae 20, no. 2 (February 28, 2002): 191–202. http://dx.doi.org/10.5194/angeo-20-191-2002.
Full textLe Roux, Y. M., J. Ménard, J. P. Jolivet, and P. J. Davy. "<i>Letter to the Editor:</i> SCIPION, a new flexible ionospheric sounder in Senegal." Annales Geophysicae 16, no. 6 (June 30, 1998): 738–42. http://dx.doi.org/10.1007/s00585-998-0738-x.
Full textDissertations / Theses on the topic "Ionospheric techniques"
Brosie, Kayla Nicole. "Ionospheric Scintillation Prediction, Modeling, and Observation Techniques for the August 2017 Solar Eclipse." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78710.
Full textMaster of Science
Locubiche-Serra, Sergi. "Robust Carrier Tracking Techniques for GNSS Receivers affected by Ionospheric Scintillation." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/668304.
Full textGlobal Navigation Satellite Systems (GNSS) have become an indispensable tool in different areas in our modern society for positioning purposes using radio-frequency ranging signals. Some application examples are the positioning and navigation in ground, maritime and aviation environments, as well as their use in agriculture, surveying and precise timing and synchronization in communication systems and finances. The tracking stage is one of the core tasks within a GNSS receiver to keep aligned with the satellites and, to date, most receivers equip conventional tracking techniques with ease of implementation that suffice to operate in environments with favorable working conditions. However, in the recent years, the success of GNSS in open-sky environments has led to the emergence of applications that expand toward scenarios with harsher conditions, such as urban canyons and soft-indoor environments. The trend is to provide user mobile terminals such as smartphones with positioning capabilities in scenarios where receivers face new technological challenges owing to the abounding propagation impairments. In this sense, the so-called ionospheric scintillation is one of the issues degrading the performance of GNSS receivers, particularly in equatorial regions and at high latitudes. It introduces rapid carrier phase and signal power variations, and has a detrimental effect particularly onto the tracking stage. The objective of this thesis is to design and develop new techniques for the robust tracking of GNSS signals affected by ionospheric scintillation disturbances. The presented approach is based on the use of Kalman filtering techniques, and the main contributions of the thesis are three. First, the analysis of ionospheric scintillation and the tracking of carrier dynamics despite the presence of the former. We design a Kalman filter with a hybrid formulation that allows the robust monitoring of both contributions separately. This arises from carrying out a detailed analysis of ionospheric scintillation which concludes that scintillation phase variations can be characterized through autoregressive processes, and thus be dealt with within the Kalman filter in a natural manner. Second, the design of adaptive Kalman filter-based techniques that allow self-adjusting their loop bandwidth to the actual scintillation conditions, which are rather time-varying in practice. This part includes a scintillation detector, a real-time estimator of the autoregressive model parameters, and an implementation to address the problem of non-linear signal amplitude attenuation introduced by scintillation itself. The goodness of the proposed techniques is later validated by carrying out an extensive simulation campaign using both synthetic data and real scintillation time series, and the outperformance region with respect to conventional tracking techniques is quantified. Third, a novel method for the derivation of expressions for the termed Bayesian Cramér-Rao bound (BCRB), which allow characterizing the behavior of Kalman filters in a closed-form manner, thus becoming a contribution to the literature of practical usefulness to design Kalman filters for any kind of application.
ROMERO, GAVIRIA RODRIGO MANUEL. "Estimation Techniques and Mitigation Tools for Ionospheric effects on GNSS Receivers." Doctoral thesis, Politecnico di Torino, 2015. http://hdl.handle.net/11583/2616928.
Full textBergadà, Caramés Pau. "Oblique Sounding and HF Communication Techniques for Very Long Haul Ionospheric Links." Doctoral thesis, Universitat Ramon Llull, 2015. http://hdl.handle.net/10803/285837.
Full textLos sistemas de radio de alta frecuencia (HF, en inglés) son usados por agencias gubernamentales y no gubernamentales en todo el mundo siempre que se necesite una alternativa a las comunicaciones por satélite: barcos en alta mar, aviones fuera del rango de cobertura de las redes radio de visión directa, operaciones militares, zonas donde la infraestructura ha sido destruida por algún desastre. Ésta ofrece una alternativa, o representa un sistema de backup, a las comunicaciones vía satélite, evitando los costes, la vulnerabilidad y los problemas de soberanía de las comunicaciones por satélite. En esta tesis se ha estudiado el enlace HF entre la base antártica española Juan Carlos I en la isla Livingston, en las Shetland del sur y España. El objetivo de este trabajo es el estudio de las limitaciones de la propagación ionosférica (como la relación señal a ruido e interferencia, la dispersión multicamino y la dispersión por efecto Doppler) y el diseño de la capa física de un enlace HF de baja velocidad, baja potencia y largo alcance. Se han estudiado un par de propuestas para este enlace, como son el espectro ensanchado por secuencia directa (DSSS, en inglés) y la multiplexación por división en frecuencia ortogonal (OFDM, en inglés). El reto ha sido definir las características que mejor se adecuan a este enlace para poder aprovechar la diversidad temporal y frecuencial que ofrece el canal HF. Desde el año 2003 diversas campañas de sondeo han permitido estudiar el canal HF pero no es hasta la campaña 2009/2010 que se consigue una fotografía de la actividad ionosférica tanto nocturna como diurna. En los artículos que se presentan en esta tesis hemos extendido los estudios previos a todo el rango de frecuencias HF y hemos mostrado las diferencias entre el día y la noche. Hemos usado estos resultados de caracterización del canal para diseñar y comparar símbolos DSSS y símbolos OFDM. Ambas posibilidades han resultado ser posibles candidatas para implementar un enlace HF de baja velocidad entre la Antártida y España. Sin embargo ambas técnicas representan dos aproximaciones distintas a la implementación del módem. Mientras que DSSS consigue un buen funcionamiento a baja velocidad en escenarios con baja relación señal a ruido, OFDM consigue tasas de transmisión más altas en escenarios más benignos.
High Frequency (HF) radio is used by governmental and non nongovernmental agencies worldwide whenever an alternative to satellites for sky wave communication is needed: ships at sea, aircraft out of range of line-of-sight radio networks, military operations, disaster areas with communication infrastructure destroyed or distant regions lacking other communications. It offers an alternative to satellites, or a backup, for long-haul communications, thus avoiding the costs, vulnerabilities and sovereignty concerns of satellite communications. In this thesis the HF link between the Antarctic Spanish Station Juan Carlos I in Livingston Island, South Shetlands and Spain is studied. The aim of this study is to address the impairments that affect HF propagation (i.e., signal-to-noise plus interference ratio, multipath and Doppler shift and spread) and to design the physical layer of a low rate, low power and long-haul HF link. Some proposals regarding this last issue are addressed, i.e., direct sequence spread spectrum (DSSS) and orthogonal frequency division multiplexing (OFDM). The challenge is to define the symbol characteristics that best fit the link to benefit from time and frequency diversity that offers the HF channel. Since 2003 several transmission campaigns have allowed to study the HF channel but it is not until the 2009/2010 campaign that we have achieved a whole picture of both diurnal and nocturnal ionospheric activity. In the papers presented in this thesis we have extended the previous research to the whole range of HF frequencies and we have shown the differences on performance between day and night. We have used the results from channel characterization to design and compare the performance of DSSS and OFDM symbols. Both techniques have turned out to be possible candidates to implement a low rate HF link between Antarctica and Spain. However, both techniques stand for different approaches of the modem: DSSS achieves good performance at low data rate in low SNR scenarios, whereas OFDM achieves higher data rate in benign channels
Elvidge, Sean. "On the use of multi-model ensemble techniques for ionospheric and thermospheric characterisation." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/5526/.
Full textKindervatter, Tim. "Survey of Ionospheric Propagation Effects and Modeling Techniques for Mitigation of GPS Error." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1515106508878179.
Full textMahmoudian, Alireza. "New-Measurement Techniques to Diagnose Charged Dust and Plasma Layers in the Near-Earth Space Environment Using Ground-Based Ionospheric Heating Facilities." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/19239.
Full textsource region associated with mesospheric dusty space plasmas may be modulated by radio wave heating with ground-based ionospheric heating facilities. These experiments show great promise as a diagnostic for the associated dusty plasma in the Near-Earth Space Environment which is believed to have links to global change. This provides an alternative to more complicated and costly space-based observational approaches to investigating these layers. This dissertation seeks to develop new analytical and computational models to investigate fundamental physics of the associated dusty plasmas as well as utilize experimental observations during High Frequency HF ground-based heating experiments to develop practical techniques for diagnosing these dusty plasma layers.
The dependency of the backscattered signal strength (i.e. Polar Mesospheric Summer Echoes PMSEs) after the turn-on and turn-off of the radio wave heating on the radar frequency is an unique phenomenon that can shed light on the unresolved issues associated with the basic physics of the natural charged mesospheric dust layer. The physical process after turn-on and turn-off of radio wave heating is explained by competing ambipolar diffusion and dust charging processes. The threshold radar frequency and dust parameters for the enhancement or suppression of radar echoes after radio wave heating turn-on are investigated for measured mesospheric plasma parameters. The effect of parameters such as the electron temperature enhancement during radiowave heating, dust density, dust charge polarity, ion-neutral collision frequency, electron density and dust radius
on the temporal evolution of electron irregularities associated with PMSE is investigated.
The possibility of observing the turn-on overshoot (enhancement of radar echoes after the
radiowave turn-on) in the high frequency HF radar band is discussed based on typical mesospheric
parameters. It has been shown that predicted enhancement of electron irregularity
amplitude after heater turn-on at HF band is the direct manifestation of the dust charging
process in the space. Therefore further active experiments of PMSEs should be pursued
at HF band to illuminate the fundamental charging physics in the space environment to
provide more insight on this unique medium. Preliminary observation results of HF PMSE
heating experiment with the new 7.9 MHz radar at the European Incoherent Scatter EISCAT
facility appear promising for the existence of PMSE turn-on overshoot. Therefore, future
experimental campaigns are planned to validate these predictions.
Computational results are used to make predictions for PMSE active modification experiments at 7.9, 56, 139, 224 and 930MHz corresponding to existing ionospheric heating facilities. Data from a 2009 very high frequency VHF (224 MHz) experiment at EISCAT
is compared with the computational model to obtain dust parameters in the PMSE. The
estimated dust parameters as a result of these comparison show very reasonable agreement to dust radius and density at PMSE altitudes measured during a recent rocket experiment providing validation to the computational model.
The first comprehensive analytical model for the temporal evolution of PMSE after heater
turn-on is developed and compared to a more accurate computational model as a reference.
It is shown that active PMSE heating experiments involving multiple observing frequencies
at 7.9 (HF), 56, and 224 MHz (VHF) may contribute further diagnostic capabilities since
the temporal evolution of radar echoes is substantially different for these frequency ranges.
It is shown that conducting PMSE active experiments at HF and VHF band simultaneously
may allow estimation of the dust density altitude profile, dust charge state variation during
the heating cycle, and ratio of electron temperature enhancement in the irregularity source
region. These theoretical and computational models are extended to study basic physics of the evolution of relevant dusty plasma instabilities thought to play an important role in irregularity production in mesospheric dust layers. A key focus is the boundary layer of these charged dust clouds. Several aspects of the cloud\'s structure (thickness of boundary layer, average particle size and density, collisional processes, and cloud expansion speed) and the ambient plasma are varied to determine the effect of these quantities on the resulting irregularities.
It was shown that for high collision frequencies, the waves may be very weakly excited (or
even quenched) and confined to the boundary layer. The excited dust acoustic waves inside
the dust cloud with frequency range of 7-15Hz and in the presence of electron bite-outs is
consistent with measured low frequency waves near 10 Hz by sounding rocket experiments
over the past decade. The observed radar echoes associated with the artificially created dust
clouds at higher altitudes in the ionosphere including space shuttle exhaust and upcoming
active space experiments in which localized dust layers will be created by sounding rockets
could be related to the excited acoustic waves predicted.
Finally, variation of spatial structures of plasma and dust (ice) irregularities in the PMSE
source region in the presence of positively charged dust particles is investigated. The correlation and anti-correlation of fluctuations in the electron and ion densities in the background plasma are studied considering the presence of positive dust particle formation. Recent rocket payloads have studied the properties of aerosol particles within the ambient plasma environment in the polar mesopause region and measured the signature of the positively charged particles with number densities of (2000 cm"3) for particles of 0.5-1 nm in radius.
The measurement of significant numbers of positively charged aerosol particles is unexpected from the standard theory of aerosol charging in plasma. Nucleation on the cluster ions is one of the most probable hypotheses for the positive charge on the smallest particles. The utility being that it may provide a test for determining the presence of positive dust particles.
The results of the model described show good agreement with observed rocket data. As an
application, the model is also applied to investigate the electron irregularity behavior during
radiowave heating assuming the presence of positive dust particles. It is shown that the
positive dust produces important changes in the behavior during Polar Mesospheric Summer Echo PMSE heating experiments that can be described by the fluctuation correlation and anti-correlation properties.
The second part of this dissertation is dedicated to Stimulated Electromagnetic Emissions SEEs produced by interaction of high power electromagnetic waves in the ionosphere. Nearearth ionospheric plasma presets a neutral laboratory for investigation of nonlinear wave phenomena in plasma which can not be studied in the laboratory environment due to the effect of physical boundary conditions. This process has been of great interest due to the
important diagnostic possibilities involving ability to determine mass of constitutive ions in
the interaction region through measurements of various gyro-frequencies. Objectives include
the consideration of the variation of the spectral behavior under pump power, proximity to
the gyro-harmonic frequency, and beam angle. Also, the relationship between such spectral
features and electron acceleration and creation of plasma irregularities was an important
focus.
Secondary electromagnetic waves excited by high power electromagnetic waves transmitted
into the ionosphere, commonly know as Stimulated Electromagnetic Emissions SEEs,
produced through Magnetized Stimulated Brillouin Scatter MSBS are investigated. Data
from two recent research campaigns at the High Frequency Active Auroral Research Program
facility HAARP is presented in this work. These experiments have provided additional
quantitative interpretation of the SEE spectrum produced by MSBS to yield diagnostic measurements of the electron temperature in the heated ionosphere. SEE spectral emission lines corresponding to ion acoustic IA and electrostatic ion cyclotron EIC modes were observed with a shift in frequency up to a few tens of Hz from radio waves transmitted near the third harmonic of the electron gyro-frequency 3fce. The threshold of each emission line has been measured by changing the pump wave amplitude. The experimental results aimed to show the threshold for transmitter power to excite IA waves propagating along the magnetic field lines as well as for EIC waves excited at oblique angles relative to the background magnetic field. A full wave solution has been used to estimate the amplitude of the electric field at the interaction altitude. The estimated growth rate using the theoretical model is compared with the threshold of MSBS lines in the experiment and possible diagnostic information for the background ionospheric plasmas is discussed. Simultaneous formation of artificial field aligned irregularities FAIs and suppression of the MSBS process is investigated. Recently, there has been significant interest in ion gyro-harmonic structuring the Stimulated Electromagnetic Emission SEE spectrum due to the potential for new diagnostic information available about the heated volume and ancillary processes such as creation of artificial ionization layers. These relatively recently discovered emission lines have almost exclusively been studied for second electron gyro-harmonic heating. The first extensive systematic investigations of the possibility of these spectral features for third electron gyro-harmonic heating are provided here. Discrete spectral features shifted from the transmit frequency ordered by harmonics of the ion gyro-frequency were observed for third electron gyro-harmonic heating for the first time at a recent campaign at a High Frequency Active Auroral Research Program Facility HAARP. These features were also closely correlated with a broader band feature at a larger frequency shift from the transmit frequency known as the Downshifted Peak DP. The power threshold of these spectral features was measured, as well as their behavior with heater
beam angle, and proximity of the transmit frequency to the third electron gyro-harmonic frequency. Comparisons were also made with similar spectral features observed during 2nd
electron gyro-harmonic heating during the same campaign. A theoretical model is provided
that interprets these spectral features as resulting from parametric decay instabilities in
which the pump field ultimately decays into high frequency upper hybrid/electron Bernstein
and low frequency neutralized ion Bernstein IB and/or obliquely propagating ion acoustic
waves at the upper hybrid interaction altitude. Coordinated optical and SEE observations
were carried out in order to provide a better understanding of electron acceleration and precipitation
processes. Optical emissions were observed associated with SEE gyro-harmonic
features for pump heating near the second electron gyro-harmonic during the campaign. The
observations affirm strong correlation between the gyro-structures and the airglow.
Ph. D.
Oronsaye, Samuel Iyen Jeffrey. "Updating the ionospheric propagation factor, M(3000)F2, global model using the neural network technique and relevant geophysical input parameters." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1001609.
Full textDamtie, B. (Baylie). "New incoherent scatter radar measurement techniques and data analysis methods." Doctoral thesis, Oulun yliopisto, 2004. http://urn.fi/urn:isbn:9514273125.
Full textOriginal papers The original papers are not included in the electronic version of the dissertation. Lehtinen, M., Markkanen, J., Väänänen, A., Huuskonen, A., Damtie, B., Nygrén, T., & Rahkola, J. (2002). A new incoherent scatter technique in the EISCAT Svalbard Radar. Radio Science, 37(4), 3-1-3–14. https://doi.org/10.1029/2001rs002518 Damtie, B., Nygrén, T., Lehtinen, M. S., & Huuskonen, A. (2002). High resolution observations of sporadic-E layers within the polar cap ionosphere using a new incoherent scatter radar experiment. Annales Geophysicae, 20(9), 1429–1438. https://doi.org/10.5194/angeo-20-1429-2002 Damtie, B., Lehtinen, M. S., & Nygrén, T. (2004). Decoding of Barker-coded incoherent scatter measurements by means of mathematical inversion. Annales Geophysicae, 22(1), 3–13. https://doi.org/10.5194/angeo-22-3-2004 Lehtinen, M. S., Damtie, B., & Nygrén, T. (2004). Optimal binary phase codes and sidelobe-free decoding filters with application to incoherent scatter radar. Annales Geophysicae, 22(5), 1623–1632. https://doi.org/10.5194/angeo-22-1623-2004
Cruz, Edith Liliana Macotela. "Contribuição ao estudo de distúrbios ionosféricos utilizando a técnica de VLF." Universidade Presbiteriana Mackenzie, 2015. http://tede.mackenzie.br/jspui/handle/tede/1301.
Full textConselho Nacional de Desenvolvimento Científico e Tecnológico
The Earth-Low ionosphere system behaves as a waveguide for the propagation of radio waves of very low frequency (VLF). If in this system the electrical conductivity of its boundaries is perturbed, the propagation of the VLF waves will also be perturbed. There is a diversity of transient physical phenomena that are able to alter significantly the electrical conductivity of the lower ionosphere. The disturbance in this region is able to produce phase and amplitude variations with respect to a quiescent level of these waves. The aim of the present work is to study the response of the lower ionosphere to phenomena originated in the Earth, our solar system or even much farther away. For this purpose, VLF data obtained by SAVNET (South American VLF Network) during the solar cycle 24 was used. It was found that the correction by both the length of the path illuminated by the flare and the reference height coefficient allows normalizing the effect of ionospheric disturbances observed in the VLF phase signals that propagated along trajectories with a north-south or west-east direction, separately. The lower limit of detection for disturbances caused by the X-ray radiation excess is 1.8×10−9 Jm-2 and 2.6×10−7 Jm-2 for the nighttime and daytime lower ionosphere, respectively. Changes in the periodicities of the VLF signal, in the infrasonic band, were observed between 6 and 14 days prior to the seismic events, of magnitude 7, occurred in Haiti in 2010 and in Peru in 2011. Increases in the periodicities of the order of few minutes were observed when the shadow of the total solar eclipse of 2010 was moving on the Earth. Due to the solar eclipse the ionospheric reference height increased in ~3 km and the electron density decreased in 60 % of its quiescent level. Finally, it was found that the effective recombination coefficient, for 80 km height, was 1.1×10−5 cm-3s-1 during the time of the eclipse, which is an intermediate value between the diurnal and nocturnal conditions.
O sistema Terra-baixa ionosfera se comporta como um guia de onda para a propagação de ondas de rádio de frequências muito baixa (VLF). Se neste sistema a condutividade elétrica das fronteiras é perturbada, a propagação da onda é também perturbada. Existe uma variedade de fenômenos físicos transientes que alteram significativamente a condutividade elétrica da baixa ionosfera. Essas alterações são observadas como variações da fase e/ou amplitude com respeito ao nível quiescente. O presente trabalho tem como finalidade estudar a resposta da baixa ionosfera a fenômenos que produzidos na Terra, no sistema solar e até aqueles produzidos muito além do sistema solar. Com esse fim foram utilizados dados de VLF de fase e de amplitude fornecidos pela rede SAVNET (South America VLF NETwork) para o ciclo solar 24. Foi encontrado que a correção pelo fator de distância iluminada e o coeficiente de altura de referência permitem normalizar o efeito do distúrbio ionosférico a partir do sinal de VLF propagado em trajetos com direção de propagação norte-sul ou oeste-leste. O limiar de detecção das perturbações causadas pelo excesso na incidência dos raios-X é 1,8×10−9 Jm-2 para a ionosfera noturna e 2,6×10−7 Jm-2 para a ionosfera diurna. Perturbações ionosféricas observadas como alterações nos períodos do sinal de VLF, na faixa de infrassom, foram observadas entre 6 e 14 dias antes dos eventos sísmicos de magnitude 7 acontecidos no Haiti no ano 2010 e no Peru no ano 2011. Alterações nas periodicidades, da ordem de dezenas de minutos, foram observadas quando a sombra do eclipse solar total de 2010 se deslocava sobre a Terra. Devido ao eclipse, a altura de referência da ionosfera aumentou em ~3 km e a densidade eletrônica diminuiu em 60% com respeito do nível quiescente. Finalmente, foi encontrado que o coeficiente de recombinação efetiva, para o tempo do eclipse e para uma altura de 80 km, foi de 1,1×10−5 cm-3s-1, que é um valor intermediário entre as condições diurnas e noturnas.
Books on the topic "Ionospheric techniques"
Radio techniques for probing the terrestrial ionosphere. Berlin: Springer-Verlag, 1991.
Find full textRadio wave propagation: Principles and techniques. Chichester: John Wiley, 2000.
Find full textG, Laneve, Herrero F. A, and European Geophysical Society, eds. Space techniques for acquisition of aeronomic-ionospheric data in the lower thermosphere. Oxford: Pergamon, 2001.
Find full textUnited States. National Aeronautics and Space Administration., ed. Investigation of radio wave propagation in the Martian ionosphere utilizing HF sounding techniques: Thesis ... [Washington, D.C: National Aeronautics and Space Administration, 1996.
Find full textInstitution, of Engineering and Technology International Conference on Ionospheric Radio Systems and Techniques (10th 2006 London England). The 10th Institution of Engineering and Technology International Conference on Ionospheric Radio Systems and Techniques: (IRST2006) : 18 -21 July 2006. London: The Royal Society of Medicine, 2006.
Find full textHunsucker, Robert D. Radio Techniques for Probing the Terrestrial Ionosphere. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-76257-4.
Full textHunsucker, Robert D. Radio Techniques for Probing the Terrestrial Ionosphere. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991.
Find full text1931-, Liu C. H., World Ionosphere/Thermosphere Study (Organization), International Council of Scientific Unions. Scientific Committee on Solar-Terrestrial Physics, and National Science Foundation (U.S.), eds. WITS handbook. [Washington, D.C.?: National Science Foundation], 1990.
Find full textURSI/IAU Symposium on Radio Astronomical Seeing (1989 Beijing, China). Proceedings of URSI/IAU Symposium on Radio astronomical seeing, 15-19 May 1989, Beijing, China. Edited by Baldwin J. E, Wang Shouguan, and International Union of Radio Science. [Beijing, China]: International Academic Publishers, 1990.
Find full textUnited States. National Aeronautics and Space Administration., ed. Global auroral imaging for the Dynamics Explorer mission: NAG5-483 : summary of research, November 01, 1984-January 31, 1998. Iowa City, IA: Dept. of Physics and Astronomy, University of Iowa, 1998.
Find full textBook chapters on the topic "Ionospheric techniques"
Hunsucker, Robert D. "Ionospheric Modification by High Power Radio Waves." In Radio Techniques for Probing the Terrestrial Ionosphere, 142–64. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-76257-4_6.
Full textRodriguez, P., C. L. Siefring, D. G. Haas, M. M. Baumback, and D. P. McNutt. "In Situ Detection of Ionospheric Cavitons: Experimental Considerations." In Measurement Techniques in Space Plasmas: Particles, 73–77. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm102p0073.
Full textHolzworth, R. H., and E. A. Bering. "Ionospheric electric fields from stratospheric balloon-borne probes." In Measurement Techniques in Space Plasmas: Fields, 79–84. Washington, D. C.: American Geophysical Union, 1998. http://dx.doi.org/10.1029/gm103p0079.
Full textGilchrist, B. E., R. A. Heelis, and W. J. Raitt. "Ionospheric multi-point measurements using tethered satellite sensors." In Measurement Techniques in Space Plasmas: Fields, 317–23. Washington, D. C.: American Geophysical Union, 1998. http://dx.doi.org/10.1029/gm103p0317.
Full textFenrich, F. R., C. L. Waters, M. Connors, and C. Bredeson. "Ionospheric signatures of ULF waves: Passive radar techniques." In Magnetospheric ULF Waves: Synthesis and New Directions, 259–71. Washington, D. C.: American Geophysical Union, 2006. http://dx.doi.org/10.1029/169gm17.
Full textYeoman, T. K., D. M. Wright, and L. J. Baddeley. "Ionospheric signatures of ULF waves: Active radar techniques." In Magnetospheric ULF Waves: Synthesis and New Directions, 273–88. Washington, D. C.: American Geophysical Union, 2006. http://dx.doi.org/10.1029/169gm18.
Full textPollock, C. J., V. N. Coffey, J. D. England, N. G. Martinez, T. E. Moore, and M. L. Adrian. "Thermal Electron Capped Hemisphere Spectrometer (TECHS) for Ionospheric Studies." In Measurement Techniques in Space Plasmas: Particles, 201–7. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm102p0201.
Full textFiori, Robyn A. D. "Spherical Cap Harmonic Analysis Techniques for Mapping High-Latitude Ionospheric Plasma Flow—Application to the Swarm Satellite Mission." In Ionospheric Multi-Spacecraft Analysis Tools, 189–218. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-26732-2_9.
Full textGarcía-Fernández, Miquel, Manuel Hernandez-Pajares, Jose Miguel Juan-Zornoza, and Jaume Sanz-Subirana. "An Improvement of Retrieval Techniques for Ionospheric Radio Occultations." In First CHAMP Mission Results for Gravity, Magnetic and Atmospheric Studies, 430–40. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-540-38366-6_59.
Full textFinlay, Christopher C. "Models of the Main Geomagnetic Field Based on Multi-satellite Magnetic Data and Gradients—Techniques and Latest Results from the Swarm Mission." In Ionospheric Multi-Spacecraft Analysis Tools, 255–84. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-26732-2_12.
Full textConference papers on the topic "Ionospheric techniques"
Chatellier, C. "Image coding and ionospheric link." In 8th International Conference on High-Frequency Radio Systems and Techniques. IEE, 2000. http://dx.doi.org/10.1049/cp:20000139.
Full textUnderhill, M. J. "A comparison of methods for the measurement of ionospheric tilt from a topside ionospheric sounder." In 8th International Conference on High-Frequency Radio Systems and Techniques. IEE, 2000. http://dx.doi.org/10.1049/cp:20000180.
Full textKunitsyn, V. E., E. D. Tereshchenko, E. S. Andreeva, I. A. Nesterov, and M. O. Nazarenko. "Ionospheric mapping and radio tomography." In IET 11th International Conference on Ionospheric Radio Systems and Techniques (IRST 2009). IEE, 2009. http://dx.doi.org/10.1049/cp.2009.0027.
Full textZakharenkova, I. E., and I. I. Shagimuratov. "Using of global and regional ionospheric maps to study of the preseismic ionosphere modification." In IET 11th International Conference on Ionospheric Radio Systems and Techniques (IRST 2009). IEE, 2009. http://dx.doi.org/10.1049/cp.2009.0025.
Full textVastberg, A. "RaTS, a system for ionospheric ray tracing." In Sixth International Conference on `HF Radio Systems and Techniques'. IEE, 1994. http://dx.doi.org/10.1049/cp:19940525.
Full textSanz-Gonzalez, J. L., S. Zazo-Bello, I. A. Perez-Alvarez, and J. Lopez-Perez. "Parameter estimation algorithms for ionospheric channels." In IET 11th International Conference on Ionospheric Radio Systems and Techniques (IRST 2009). IEE, 2009. http://dx.doi.org/10.1049/cp.2009.0023.
Full textNdao, P. M., D. Lemur, Y. Erhel, and C. Brousseau. "Capacity estimation of MIMO ionospheric channels." In IET 11th International Conference on Ionospheric Radio Systems and Techniques (IRST 2009). IEE, 2009. http://dx.doi.org/10.1049/cp.2009.0032.
Full textJackson-Booth, N. K., P. S. Cannon, M. Bradley, and P. A. Arthur. "New oblique sounders for ionospheric research." In 12th IET International Conference on Ionospheric Radio Systems and Techniques (IRST 2012). IET, 2012. http://dx.doi.org/10.1049/cp.2012.0363.
Full textMilsom, J. D. "The evolution of an ionospheric forecasting service." In 8th International Conference on High-Frequency Radio Systems and Techniques. IEE, 2000. http://dx.doi.org/10.1049/cp:20000171.
Full textBartlett, A. "A flexible, low-cost, ionospheric sounding system." In IEE Colloquium on Frequency Selection and Management Techniques for HF Communications. IEE, 1996. http://dx.doi.org/10.1049/ic:19960119.
Full textReports on the topic "Ionospheric techniques"
Basu, Sunanda. Multi-Technique Studies of Ionospheric Plasma Structuring. Fort Belvoir, VA: Defense Technical Information Center, September 2006. http://dx.doi.org/10.21236/ada612082.
Full textBasu, Sunanda. Multi-technique Studies of Ionospheric Plasma Structuring. Fort Belvoir, VA: Defense Technical Information Center, September 2008. http://dx.doi.org/10.21236/ada533973.
Full textBasu, Sunanda. Multi-Technique Studies of Ionospheric Plasma Structuring. Fort Belvoir, VA: Defense Technical Information Center, September 2007. http://dx.doi.org/10.21236/ada573400.
Full textBasu, Sunanda. Multi-technique Studies of Ionospheric Plasma Structuring. Fort Belvoir, VA: Defense Technical Information Center, September 2009. http://dx.doi.org/10.21236/ada602953.
Full textKeskinen, Michael J. Development of Multiscale Ionosphere-thermosphere Forecasting Techniques and Models. Fort Belvoir, VA: Defense Technical Information Center, September 1997. http://dx.doi.org/10.21236/ada629247.
Full textReinisch, Bodo, and Gary Sales. Measuring Electrodynamics of the Ionosphere by Digital Ionosondes and Other Techniques. Fort Belvoir, VA: Defense Technical Information Center, July 2000. http://dx.doi.org/10.21236/ada401996.
Full textReinisch, Bodo, and Gary Sales. Measuring Electrodynamics of the Ionosphere by Digital Ionosondes and Other Techniques. Fort Belvoir, VA: Defense Technical Information Center, March 2001. http://dx.doi.org/10.21236/ada402979.
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