<i>D</i> region absorption effects during high‐power radio wave heating

Abstract

Simultaneous solutions of the differential equations governing electron energy and power flow are used to study D region absorption effects arising from high‐power HF heating. It is shown that self‐absorption of the heating wave can severely limit HF heating of the upper ionosphere and that the power density available for heating above the D region saturates as the heating power is increased. Models of the electron temperature distribution under heated conditions are used to compute the change in two‐way integral absorption on a 2.4‐MHz diagnostic wave due to HF heating as a function of heating frequency. The predicted theoretical absorption change is found to agree with experimental results.