Linear mode conversion in inhomogeneous magnetized plasmas during ionospheric modification by HF radio waves

Abstract

The propagation of high‐frequency (HF) radio waves in an inhomogeneous magnetoactive plasma and generation of plasma waves at the resonance layer near the reflection layer of the ordinary mode are studied using one‐dimensional (1‐D) and two‐dimensional full‐wave codes. The characteristics of the mode‐conversion process are investigated in linear and parabolic density profiles as the angle of incidence is varied. We present the 1‐D results for the wave propagation relevant to the high‐latitude heater facility at Tromsø and the midlatitude facility at Arecibo. For the facility at Arecibo, the 2‐D wave propagation in a plasma density approximating an overdense sporadic‐ E patch is investigated to determine the localized regions of amplified intensity, where plasma waves can facilitate acceleration of fast energetic electrons, resulting in observed enhanced airglow.