Dispersion Characteristics and Waveform Analysis of Tweek Atmospherics

The frequency characteristics and the waveforms of tweeks are analyzed theoretically. In the waveform analysis the mode current method is used: a method based upon the source current expansion and the multi-reflection. In the theory the source current is Fourier-expanded by using the electric images. The calculated frequency dispersion and the first mode waveform are compared with the observed ones and discussions follow.