Adaptive Smoothness Constraint Ionospheric Tomography Algorithm

Computerized Ionospheric Tomography

ith the transition to the Global Positioning System, Transit has been decommissioned, after having served well for the Fleet. A new system, the Navy Ionospheric Monitoring System, was established using Transit satellites. This article examines the application of the new system to the field of computerized ionospheric tomography. (

Ionospheric Correction Using Tomography

The most demanding application of wide area di erential corrections to GPS is vertical positioning of aircraft on precision approach. Here the Wide Area Augmentation System (WAAS) combines accuracy requirements on the order of ones of meters with safety of life integrity requirements which specify that any vertical position errors greater than the Vertical Protection Limit be enunciated to the ...

Multiresolution Tomography of Ionospheric Electron Density

Algorithm for the Separation of Harmonic Sounds with Time- Frequency Smoothness Constraint

A signal model is described which forces temporal and spectral smoothness of harmonic sounds. Smoothness refers to harmonic partials, the amplitudes of which are slowly-varying as a function of time and frequency. An algorithm is proposed for the estimation of the model parameters. The algorithm is utilized in a sound separation system, the robustness of which is increased by the smoothness con...

Ionospheric Sounding and Tomography by GNSS

Studies of the ionosphere and the physics of the ionospheric processes rely on the knowledge of spatial distribution of the ionospheric plasma. Being the propagation medium for radio waves, the ionosphere significantly affects the performance of various navigation, location, and communication systems. Therefore, investigation into the structure of the ionosphere is of interest for many practica...