This paper shows a statistical analysis of 10.2 kHz Omega broadcasts of anartificial signal broadcast from ground stations, propagated in theplasmasphere, and detected using an automatic detection method we developed. Westudy the propagation patterns of the Omega signals to understand thepropagation characteristics that are strongly affected by plasmasphericelectron density and the ambient magnetic field. We show the unique propagationpatterns of the Omega 10.2 kHz signal when it was broadcast from twohigh-middle-latitude stations. We use about eight years of data captured by thePoynting flux analyzer subsystem on board the Akebono satellite from October1989 to September 1997. We demonstrate that the signals broadcast from almostthe same latitude (in geomagnetic coordinates) propagated differently dependingon the geographic latitude. We also study propagation characteristics as afunction of local time, season, and solar activity. The Omega signal tended topropagate farther on the nightside than on the dayside and was more widelydistributed during winter than during summer. When solar activity was atmaximum, the Omega signal propagated at a lower intensity level. In contrast,when solar activity was at minimum, the Omega signal propagated at a higherintensity and farther from the transmitter station.
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