Modes of the Contrawound Toroidal Helix Antenna
نویسندگان
چکیده
The contrawound toroidal helix antenna with constant current is examined; it has an omnidirectional pattern in the toroid plane. Radiation resistance is derï ed for the dipole mode, and results are ̈alidated by moment-method calculations. The radiation Qs of these antennas are greater than one million, making them unsuitable as dipole mode radiators. Ratios of loop-mode to dipole-mode radiation resistances range from se ̈eral hundred to large ̈alues. Q 1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 23: 365]368, 1999.
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