Scatter from man-made irregularities in the ionosphericDregion

Abstract

The possibility of utilizing irregularities produced in the ionospheric D layer by radio-frequency heating or by intense optical radiation from lasers to scatter radio waves is considered. Intense beams passing through the D region can produce large horizontal gradients in electron density where the beam intensity is falling off rapidly. The mechanism in the case of radio frequency is enhancement of electron attachment rate due to electron heating and in the case of lasers is photodetachment. In these regions radio waves may be scattered from blobs produced by turbulent mixing. A recently discovered anomalous relationship between electron energy and electromagnetic field intensity gives rise to the additional possibility of producing sharp vertical gradients in the propagation characteristics of an intense high-frequency wave in a plasma. Some interesting applications to f orward scatter propagation links and to ionospheric research with the Arecibo radar are suggested.