Solid State Devices Applications for ASW. VLF Ferrite Antennas

Presented is design of VLF ferrite loaded antennas and a general review of the properties of short electrical radiators, of a general theoretical analysis of the performance of ferrite loaded antennas, of the presentation and discussion of extensive experimental verifications of the theory, and, finally, of a preliminary design of an Omega type antenna system. The latter would operate at 10.2 Kcs with a radiated power up to 20 Kw, and with an efficiency of the order of 10. While this design is tentative, it constitutes a sound reference basis for the development of a final ferrite loaded antenna system. The work discussed indicates that the use of ferrite loading provides considerable wavelength reduction along the axis of the radiator and results in structures which have radiation resistance larger than that of metal air antennas having the same height. The over all design may be achieved with satisfactory characteristics of efficiency, reliability, bandwidth and cost. The maximum radiated power is limited by the distortion which occurs when the magnetic materials becomes saturated how ever, in practice satisfactory levels of out put power may be obtained for medium power applications.