Long Wave Atmospheric Noise Model. Phase 1. Volume 1. Lightning Occurrence Rates and Propagation Theory
Abstract
Progress on a model that predicts how long wave atmospheric noise is affected by distortions in the earth ionosphere waveguide caused by high altitude nuclear bursts is described. When complete, the model will also represent worldwide noise under ambient conditions. The model comprises two submodels: source, which describes the occurrence rate of lightning flashes throughout the world; and propagation, which describes the propagation of energy radiated from centers of lightning activity. The new model is an improvement over existing ones. First, it uses recent data on the actual occurrence rate of lightning flashes as a function of time of day, latitude, and season. Second, it includes extremely low frequency and low frequency noise. Third, it use new data on the altitude and orientation of individual strokes to model transverse electric noise. Finally, the model incorporates new propagation algorithms that are nearly as accurate as full wave algorithms, but they reduce computer running time by as much as fivefold. It would be costly to recalculate mode parameters for the earth ionosphere waveguide each time the model is exercised. Instead, attenuation rate, excitation factor, phase velocity, and eigencosine are precalculated and stored for a wide range of modes, frequency, ground conductivity, and spread debris nuclear environments.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 14, 1988
- Accession Number
- ADA212794
Entities
People
- Chris R. Warber
- Edward C. Field Jr.
- Lynda R. Kies