Nuclear & Plasma Sciences & Social Implications of Technology

When ionospheric plasma becomes turbulent, radio signals that pass through it experience scintillation. Scintillation manifests as random fluctuations in phase and amplitude (and potentially in other quantities like polarization angle). The effect is similar to the optical twinkling of starlight that passes through lower-atmosphere turbulence. Ionospheric scintillation has the potential to impact systems like synthetic aperture radar (SAR), direct-to-device (D2D) satellite communications and Global Navigation Satellite System (GNSS) observations. This talk will first present an overview of the propagation physics that leads to the practical model of the ionosphere as a phase changing screen (“phase screen”). We will then explore selected deterministic and random phase screen examples to gain some intuition for amplitude and phase scintillation impacts. Finally, we examine some recent applications of scintillation observations to deducing the physical state of the ionosphere, such as the decay of equatorial plasma bubble (EPB) turbulence. Not only does scintillation allow us to track when and where ionospheric irregularities develop, careful analysis may yield more quantitative physical details of the irregularity processes.

Location:  Boston College Newton Campus, 885 Centre St, Newton MA), Newton, MA, Massachusetts.  Building: Kenny Cottle Conference Room 202

Registration

Professor Ted Beach of Boston College

Radio Wave Scintillation Propagation Models and Applications

When ionospheric plasma becomes turbulent, radio signals that pass through it experience scintillation. Scintillation manifests as random fluctuations in phase and amplitude (and potentially in other quantities like polarization angle). The effect is similar to the optical twinkling of starlight that passes through lower-atmosphere turbulence. Ionospheric scintillation has the potential to impact systems like synthetic aperture radar (SAR), direct-to-device (D2D) satellite communications and Global Navigation Satellite System (GNSS) observations. This talk will first present an overview of the propagation physics that leads to the practical model of the ionosphere as a phase changing screen (“phase screen”). We will then explore selected deterministic and random phase screen examples to gain some intuition for amplitude and phase scintillation impacts. Finally, we examine some recent applications of scintillation observations to deducing the physical state of the ionosphere, such as the decay of equatorial plasma bubble (EPB) turbulence. Not only does scintillation allow us to track when and where ionospheric irregularities develop, careful analysis may yield more quantitative physical details of the irregularity processes.

Biography:

Dr. Theodore Beach is a senior research engineer in the Institute for Scientific Research at Boston College. He has studied ionospheric scintillation since his doctoral research. He has also worked with spaceflight projects, including the Communication/Navigation Outage Forecasting System (C/NOFS) at the Air Force Research Laboratory and several CubeSat sensor and subsystem projects in the private sector. He received his Ph. D. in electrical engineering from Cornell University in 1998. He is a Senior Member of the IEEE and incoming Vice Chair of Commission G for the United States National Committee for the International Union of Radio Science (USNC-URSI).