Feasibility study of ionospheric perturbations triggered by monochromatic infrasonic waves emitted with a ground-based experiment

摘要

In the framework of an active experiment preparation with a powerful ground-based monochromatic emitter, the modification of ionospheric plasma by infrasonic waves is examined. In this paper, theoretical models and numerical calculations take into account realistic altitude temperature dependence. A modulation of the electron density for an altitude equal to similar to100 km was determined under the assumption that the plasma is a small passive admixture. To study the expected ionospheric effects we intend to use data from an ionospheric sounder and from the low-altitude Demeter satellite, which can register representative electromagnetic signals scattered by artificial ionospheric inhomogeneities. The comparison between the obtained results and the expected ones is important for the analysis of possible acoustic-gravity wave contribution to the formation of an electromagnetic earthquake precursor. The calculations developed in this paper indicate that the power of an emitter of infrasonic waves with frequencies below than 20 Hz must be equal to or larger than 10 kW to be able to trigger ionospheric perturbations. (C) 2004 Elsevier Ltd. All rights reserved.