Accession Number:
ADA139317
Title:
Active Ionospheric Generation on ELF/VLF Waves.
Descriptive Note:
Final rept. 23 Oct 82-22 Dec 83,
Corporate Author:
SCIENCE APPLICATIONS INC MCLEAN VA
Personal Author(s):
Report Date:
1984-01-09
Pagination or Media Count:
31.0
Abstract:
Our work during the past year on active ELFVLF generation has produced major breakthroughs in the understanding of nonlinear interactions in a dissipating medium such as the ionosphere for the purpose of downconverting H.F. to ELFVLF waves. A key result was the fact that the contrary to the conventional understanding of such processes, the presence of a dissipative medium lowers the threshold for complete decay and increases the downconversion efficiency over the one expected on the basis of the Manley rowe relations. Two codes were developed and optimized. I The first code named CMPOWER required as input a model of the ionospheric electron density and magnetic field, and the transmitter characteristics. Its output is the ELFVLF signal as a function of the modulation frequency and distance from the HF facility. II The second named TWC three wave coupling is a nonlinear code, which includes dissipation and finite pump size effects. Author
Descriptors:
- *Ionospheric disturbances
- *Electric generators
- *Plasma generators
- *Nonlinear systems
- *Frequency converters
- *Down converters
- Coupling(Interaction)
- Electron density
- Interactions
- Extremely low frequency
- Transmitters
- Very low frequency
- Pumping
- Magnetic fields
- Dissipation
- High frequency
- Coding
- Signals
- Ionosphere
- Facilities
- Modulation
- Waves
Subject Categories:
- Atmospheric Physics
- Plasma Physics and Magnetohydrodynamics