Equatorial Ionospheric Specification And Forecasting With HF Beacons, Radar, And Simulation
Abstract
This is a proposal to study disturbances in the low-latitude F-region ionosphere associatedwith equatorial spread F (ESF) conditions. The disturbances interfere with radio communication,navigation, and imaging systems and so pose an operartional hazard. Under a previous AFOSRaward, a 3D numerical simulation of the plasma instabilities responsible for ESF was developed.Data from the Jicamarca Radio Observatory near Lima, Peru, were used both to initialize and drivethe simulation. In a series of campaign studies, the simulation was able to recover (predict “afterthe fact”) the presence or absence of ionospheric disturbances. The simulation produced no “falsealarms,” meaning that no necessary condition for instability is being neglected. On occasion, thesimulation produced “missed detections,” failing to anticipate disturbances that occurred underseemingly unlikely circumstances. Understanding these “rogue” events which are presumed tosignify disturbances propagating into the region from outside is the focus of the current proposal.Our goal now is to monitor the ionospheric region around Jicamarca (rather than just thesmall volume directly overhead) in order to understand the rogue events and better anticipate localdisturbances. Working with Jicamarca, our group has begun deploying HF beacon stations thattransmit PRN-coded HF CW signals at two frequencies through the F region. Beacon receiversdecode the signals and register their group delay, Doppler shift, and amplitude. Other observablesinclude the polarization and bearing of the received signal. This information constitutes invertibledata which can be used to constrain a regional model of the F region in the Andean sector. Analgorithm capable of ingesting data from the beacons, the Jicamarca ISR, and other instrumentshas been constructed and is being tested.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Dec 05, 2016
- Source ID
- FA95501610465
Entities
People
- D. L. Hysell
Organizations
- Air Force Office of Scientific Research
- Cornell University
- United States Air Force