Upper hybrid mode conversion and resonance excitation of Bernstein modes in ionospheric heating experiments

Summary form only given, as follows. It is shown that the mode conversion of upper-hybrid waves to resonantly excited electrostatic electron cyclotron harmonic (Bernstein) waves is responsible for the absence of stimulated emission of electromagnetic radiation in the kilohertz frequency range at a frequency less than the input pump frequency when the latter is very close to or at the harmonics (third and above) of the electron cyclotron frequency. The results are in good agreement with the ionospheric heating experiments conducted recently at Tromso