Fig. 4From: Statistical study on propagation characteristics of Omega signals (VLF) in magnetosphere detected by the Akebono satellite a Duration of data processed in the magnetic and electric fields below altitude 640 km. b Omega signal propagation for the North Dakota station in the magnetic field and c in the electric field. The rectangle indicates the location of the North Dakota station at latitude 55.98° N and longitude 34.83° WBack to article page