The Wireless Power Transmission environment from GEO to the earth and numerical estimation of relative permittivity vs. the altitude in the neutral and ionized layers of the Earth atmosphere

摘要

Wireless Power Transmission (WPT) has been discussed as early as since 1900 year, however, has only developed intensively from 1973 to recently. In WPT system, one can wirelessly transmit a high power beam (a microwave or a laser beam) from a point to another point or from Geostationary Earth Orbit (GEO) to the Earth surface. For the WPT, getting the highest collection efficiency often is among the most desirable requirements. The collection efficiency of a wireless information system and that of the WPT could be determined by using the Free Space Path Loss models or the Friis transmission equation under idealized conditions and by using Goubau parameter (τ) with the value in the range of 1.5 -2.5, respectively. Besides, the collection efficiencies of both the wireless information system and WPT system could also calculated by using the solution of the mathematical energy flux equations but this method is particularly challenging as its mathematical expression strongly depends on the Earth atmosphere layers' the relative dielectric permittivity (ε), the relative magnetic permeability (μ) and the refractive index (n) by altitude. This paper briefly presents 1D model of WPT, discusses some main features of the energy transfer environment and then offers a numerical estimation of the refractive index (n) in the non-ionized region and the relative permittivity (ε) by altitude in both the non-ionized region from 0-90 km and the ionized region from 100 km -1000 km based on the published Pedersen and Field-aligned conductivities.