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Personal-computer-based system for real-time reconstruction of the three-dimensional ionosphere using data from diverse sources
[1] We present new capabilities of our system for monitoring the ionosphere over a fixed geographical area with dimensions of the order of several thousand kilometers. The system employs a nonlinearExpand
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Real‐time reconstruction of the three‐dimensional ionosphere using data from a network of GPS receivers
We present a system that processes phase and group delay time series from a network of dual-frequency GPS receivers and produces a dynamic ionospheric model that is consistent with all the input data. Expand
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Assimilation procedures for updating ionospheric profiles below the F2 peak
[1] This paper describes and compares two real-time assimilative ionospheric models, with an emphasis on their ability to provide accurate profiles of the electron density below the peak of the F2Expand
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Inversion of backscatter ionograms and TEC data for over-the-horizon radar
[1] Over-the-horizon radar (OTHR) uses ionospheric reflection to propagate HF transmissions to long range (∼500–5000 km). The ionosphere acts as a dynamic “mirror” that varies diurnally, seasonally,Expand
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Range rate–Doppler correlation for HF propagation in traveling ionospheric disturbance environments
[1] Using ionospheric sounding together with fast computational inverse processing, it is now possible to obtain good real-time ionospheric models for use in geolocation for over-the-horizon (OTH)Expand
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Assimilative model for ionospheric dynamics employing delay, Doppler, and direction of arrival measurements from multiple HF channels
We describe the development of new HF data assimilation capabilities for our ionospheric inversion algorithm called GPSII (GPS Ionospheric Inversion). Previously existing capabilities of thisExpand
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HiCIRF: A high‐fidelity HF channel simulation
A high-fidelity HF channel simulation has been developed that is suitable for Over-the-Horizon Radar (OTHR) and HF communication system design studies and test planning. Expand
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Target detection and tracking via sparsity-promoting Tikhonov regularization
We discuss the utilization of sparsity-promoting regularization within the SIFTER target detection capability for OTH radar. Expand
Feasibility study for reconstructing the spatial‐temporal structure of TIDs from high‐resolution backscatter ionograms
Over-the-horizon radar (OTHR) utilizes the reflective “sky wave” property of the ionosphere for high-frequency radiowaves to illuminate targets at ranges extending to several thousand kilometers.Expand
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Assimilative modeling of ionospheric dynamics for nowcasting of HF propagation channels in the presence of TIDs
The ionospheric data assimilation algorithm called GPS Ionospheric Inversion (GPSII; pronounced “gypsy”) [Fridman et al., 2006, 2012; McNamara et al., 2013] has been extended and employed to modelExpand
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