TE/TM (Transverse Magnetic/Transverse Electric) Height Profile Measurements of Transpolar VLF (Very Low Frequency) Signals

摘要

Transverse magnetic (TM) and transverse electric (TE) height-gain profiles of eight ground-based transmitters and one airborne transmitter were measured simultaneously by a rocket-borne wideband receiver flown at Thule AB, Greenland, under nighttime conditions. The profile shapes are shown to depend both on ground parameters and on solar illumination conditions over the propagation paths. Significant TM-to-TE conversion was observed for ground-based transmitters located in the night hemisphere, while none was measured for sources in daylight. No TE-to-TM conversion was measured for the airborne transmitter. (Author)