A Miniaturized UHF Vivaldi Antenna With Tailored Radiation Performance Based on Magneto-Dielectric Ferrite Materials

In this article, a miniaturized ferrite Vivaldi antenna with tailored radiation performance in ultrahigh-frequency (UHF) band is presented. The novel magneto-dielectric NiZnCo ferrite materials were prepared, characterized, and adopted for the antenna application. A parametric study on the properties of the ferrite antenna is systematically implemented. Simulation results indicate that a significant size reduction for the antenna can be achieved by taking advantage of the relatively high permittivity and permeability of the ferrite material. Moreover, the inherent magnetic loss of the ferrite antenna substrates shows an effective suppression of the unwanted harmonic frequencies. The prototype of the ferrite Vivaldi antenna was fabricated with a relatively small dimension of 50×55×2 mm
³
, and antenna performances were tested to demonstrate the simulation. The measured lowest operating frequency (S
₁₁
<; -10 dB) of the antenna is 0.82 GHz. Relatively high and flat gain is obtained in the frequency range of 0.8-0.95 GHz, while antenna gain is significantly suppressed above ~ 1.0 GHz. The experiment data is in good agreement with the simulation results.