Microstrip to Parallel-Strip Nonlinear Transition Balun with Stubs and DGS for UWB Dipole Antenna
Abstract: Three tapered baluns
with nonlinear transition are developed for harmonic suppression in dipole antenna.
The first balun consists of an exponential profile with the size of a
quarter–wavelength for both the height and width with a wideband
characteristic. However, for some applications such as narrowband harmonic
suppression antennas and wideband-to-narrowband reconfigurable antennas, the
suppression of higher operating band is desired. By employing stubs-filter and
a defected ground structure (DGS), two narrowband tapered baluns are produced.
They are named as an exponential balun-stub and an exponential balun-DGS,
respectively, that operate from 1 to 2 GHz. A simulated and measured results
that based on the reflection coefficient is found to be better than -10 dB from
1 to 2 GHz. The employment of the stubs and DGS have enabled these baluns to
have the capability to reject the unwanted higher frequency band from 2.0 to 10
GHz. Finally, the proposed baluns are employed as a feeding circuit for an ultra
wideband (UWB) circular dipole antenna that produces a reasonable outcome.
Author: S. A. Hamzah
Journal Code: jptkomputergg170038
