Theoretical Study of Wideband Antenna Using High Efficiency Impedance Loading Profile

On the basis of Wu-King current distribution, the author extends it to the double exponential current distribution, modifies the inaccurate part of the Wu-King resistive loading profile and deduces a high efficiency non-reflecting loading profile. The electrical properties of the high efficiency non-reflecting loading antenna have been studied theoretically; the concept of lengthening coefficient is created and the optimum parameter design curve of the antenna is provided. Theoretical calculation shows that the maximum bandwidth and efficiency of antenna can be achieved with this kind of loading profile simultaneously. The impedance bandwidth of antenna is as high as 40:1, which is much greater than the 3:1 bandwidth of Wu-King profile when the voltage standing wave ratio is below 3. The efficiency of antenna is about twice of the Wu-King loading antenna.